[gs-commits] ghostpdl branch, pdfi, updated. jbig2dec-0.14-2214-g6d2cc1a

The ghostpdl branch, pdfi has been updated
       via  6d2cc1ab2064254e6734f013908bdb9b5a73dca8 (commit)
       via  e0ffeda75b00f7d864cdfb785cdded5baa88c849 (commit)
      from  f86f9fef1d8e43847342faa49a77d3560b9b14e4 (commit)

----------------------------------------------------------------------
commit 6d2cc1ab2064254e6734f013908bdb9b5a73dca8
Author: Nancy Durgin <[email protected]>
Date:   Wed Sep 18 09:34:14 2019 -0700

    Clean up some optcontext stuff
    
    -- wasn't calling the routine to free it
    -- cleaned up the implementation, fixed bug in untested code

diff --git a/pdf/ghostpdf.c b/pdf/ghostpdf.c
index bb7aeeb..442455f 100644
--- a/pdf/ghostpdf.c
+++ b/pdf/ghostpdf.c
@@ -883,6 +883,7 @@ int pdfi_free_context(gs_memory_t *pmem, pdf_context *ctx)
     }
 
     pdfi_free_DefaultQState(ctx);
+    pdfi_oc_free(ctx);
 
     if (ctx->pdfi_param_list.head != NULL)
         gs_c_param_list_release(&ctx->pdfi_param_list);
diff --git a/pdf/pdf_optcontent.c b/pdf/pdf_optcontent.c
index 61f3461..70bb0c5 100644
--- a/pdf/pdf_optcontent.c
+++ b/pdf/pdf_optcontent.c
@@ -310,7 +310,7 @@ pdfi_oc_is_ocg_visible(pdf_context *ctx, pdf_dict *ocdict)
     return is_visible;
 }
 
-#define INIT_CONTENT_LEVELS 100
+#define NUM_CONTENT_LEVELS 100
 typedef struct {
     byte *flags;
     uint64_t num_off;
@@ -329,16 +329,16 @@ static int pdfi_oc_levels_init(pdf_context *ctx, pdfi_oc_levels_t **levels)
     if (!new)
         return_error(gs_error_VMerror);
 
-    data = (byte *)gs_alloc_bytes(ctx->memory, INIT_CONTENT_LEVELS, "pdfi_oc_levels_init (data)");
+    data = (byte *)gs_alloc_bytes(ctx->memory, NUM_CONTENT_LEVELS, "pdfi_oc_levels_init (data)");
     if (!data) {
         gs_free_object(ctx->memory, new, "pdfi_oc_levels_init (levels (error))");
         return_error(gs_error_VMerror);
     }
-    memset(data, 0, INIT_CONTENT_LEVELS);
+    memset(data, 0, NUM_CONTENT_LEVELS);
 
     new->flags = data;
     new->num_off = 0;
-    new->max_flags = INIT_CONTENT_LEVELS;
+    new->max_flags = NUM_CONTENT_LEVELS;
     *levels = new;
 
     return 0;
@@ -359,7 +359,7 @@ static int pdfi_oc_levels_set(pdf_context *ctx, pdfi_oc_levels_t *levels, uint64
 
     if (index > levels->max_flags) {
         /* Expand the flags buffer */
-        newmax = levels->max_flags + INIT_CONTENT_LEVELS;
+        newmax = levels->max_flags + NUM_CONTENT_LEVELS;
         if (index > newmax)
             return_error(gs_error_Fatal); /* shouldn't happen */
         new = gs_alloc_bytes(ctx->memory, newmax, "pdfi_oc_levels_set (new data)");
@@ -369,6 +369,7 @@ static int pdfi_oc_levels_set(pdf_context *ctx, pdfi_oc_levels_t *levels, uint64
         memcpy(new, levels->flags, levels->max_flags);
         gs_free_object(ctx->memory, levels->flags, "pdfi_oc_levels_set (old data)");
         levels->flags = new;
+        levels->max_flags += NUM_CONTENT_LEVELS;
     }
 
     if (levels->flags[index] == 0)
@@ -414,6 +415,15 @@ int pdfi_oc_init(pdf_context *ctx)
     return 0;
 }
 
+int pdfi_oc_free(pdf_context *ctx)
+{
+    int code;
+
+    code = pdfi_oc_levels_free(ctx, (pdfi_oc_levels_t *)ctx->OFFlevels);
+    ctx->OFFlevels = NULL;
+    return code;
+}
+
 /* begin marked content sequence */
 /* TODO: Incomplete implementation, it is ignoring the argument */
 int pdfi_op_BMC(pdf_context *ctx)
diff --git a/pdf/pdf_optcontent.h b/pdf/pdf_optcontent.h
index 71d5366..61c9d69 100644
--- a/pdf/pdf_optcontent.h
+++ b/pdf/pdf_optcontent.h
@@ -19,6 +19,7 @@
 bool pdfi_oc_is_ocg_visible(pdf_context *ctx, pdf_dict *ocdict);
 
 int pdfi_oc_init(pdf_context *ctx);
+int pdfi_oc_free(pdf_context *ctx);
 bool pdfi_oc_is_off(pdf_context *ctx);
 int pdfi_op_BMC(pdf_context *ctx);
 int pdfi_op_BDC(pdf_context *ctx, pdf_dict *stream_dict, pdf_dict *page_dict);

----------------------------------------------------------------------
commit e0ffeda75b00f7d864cdfb785cdded5baa88c849
Author: Nancy Durgin <[email protected]>
Date:   Wed Sep 18 09:09:54 2019 -0700

    Create pdf_check.c and move a bunch of code out of ghostpdf.c
    
    Move some page code to pdf_page.c
    Move the transparency and spot checking code to pdf_check.c
    
    No functional changes, just moving code around.

diff --git a/pdf/ghostpdf.c b/pdf/ghostpdf.c
index 49a0dff..bb7aeeb 100644
--- a/pdf/ghostpdf.c
+++ b/pdf/ghostpdf.c
@@ -31,1141 +31,8 @@
 #include "pdf_colour.h"
 #include "pdf_font.h"
 #include "pdf_text.h"
-#include "pdf_optcontent.h"
-
-/* This routine is slightly misnamed, as it also checks ColorSpaces for spot colours.
- * This is done at the page level, so we maintain a dictionary of the spot colours
- * encountered so far, which we consult before adding any new ones.
- */
-static int pdfi_check_Resources_for_transparency(pdf_context *ctx, pdf_dict *Resources_dict, pdf_dict *page_dict, bool *transparent, int *num_spots);
-
-/* For performance and resource reasons we do not want to install the transparency blending
- * compositor unless we need it. Similarly, if a device handles spot colours it can minimise
- * memory usage if it knows ahead of time how many spot colours there will be.
- *
- * The PDF interpreter written in PostScript performed these as two separate tasks, on opening
- * a PDF file it would count spot colour usage and then for each page it would chek if the page
- * used any transparency. The code below is used to check for both transparency and spot colours.
- * If the int pointer to num_spots is NULL then we aren't interested in spot colours (not supported
- * by the device), if the int pointer to transparent is NULL then we aren't interested in transparency
- * (-dNOTRANSPARENCY is set).
- *
- * Currenlty the code is run when we open the PDF file, the existence of transparency on any given
- * page is recorded in a bit array for later use. If it turns out that checking every page when we
- * open the file is a performance burden then we could do it on a per-page basis instead. NB if
- * the device supports spot colours then we do need to scan the file before starting any page.
- *
- * The technique is fairly straight-forward, we start with each page, and open its Resources
- * dictionary, we then check by type each possible resource. Some resources (eg Pattern, XObject)
- * can themselves contain Resources, in which case we recursively check that dictionary. Note; not
- * all Resource types need to be checked for both transparency and spot colours, some types can
- * only contain one or the other.
- *
- * Routines with the name pdfi_check_xxx_dict are intended to check a Resource dictionary entry, this
- * will be a dictioanry of names and values, where the values are objects of the given Resource type.
- *
- */
-
-/*
- * Check the Resources dictionary ColorSpace entry. pdfi_check_ColorSpace_for_spots is defined
- * in pdf_colour.c
- */
-static int pdfi_check_ColorSpace_dict(pdf_context *ctx, pdf_dict *cspace_dict, pdf_dict *page_dict, int *num_spots)
-{
-    int code, i, index;
-    pdf_obj *Key = NULL, *Value = NULL;
-
-    if (pdfi_dict_entries(cspace_dict) > 0) {
-        code = pdfi_loop_detector_mark(ctx); /* Mark the start of the ColorSpace dictionary loop */
-        if (code < 0)
-            return code;
-
-        code = pdfi_dict_first(ctx, cspace_dict, &Key, &Value, (void *)&index);
-        if (code < 0)
-            goto error1;
-
-        i = 1;
-        do {
-            code = pdfi_check_ColorSpace_for_spots(ctx, Value, cspace_dict, page_dict, num_spots);
-            if (code < 0)
-                goto error2;
-
-            pdfi_countdown(Key);
-            Key = NULL;
-            pdfi_countdown(Value);
-            Value = NULL;
-
-            (void)pdfi_loop_detector_cleartomark(ctx); /* Clear to the mark for the Shading dictionary loop */
-
-            code = pdfi_loop_detector_mark(ctx); /* Mark the new start of the Shading dictionary loop */
-            if (code < 0)
-                goto error1;
-
-            do {
-                if (i++ >= pdfi_dict_entries(cspace_dict)) {
-                    code = 0;
-                    goto transparency_exit;
-                }
-
-                code = pdfi_dict_next(ctx, cspace_dict, &Key, &Value, (void *)&index);
-                if (code == 0 && Value->type == PDF_ARRAY)
-                    break;
-                pdfi_countdown(Key);
-                Key = NULL;
-                pdfi_countdown(Value);
-                Value = NULL;
-            } while(1);
-        }while (1);
-    }
-    return 0;
-
-transparency_exit:
-error2:
-    pdfi_countdown(Key);
-    pdfi_countdown(Value);
-
-error1:
-    (void)pdfi_loop_detector_cleartomark(ctx); /* Clear to the mark for the current resource loop */
-    return code;
-}
-
-/*
- * Process an individual Shading dictionary to see if it contains a ColorSpace with a spot colour
- */
-static int pdfi_check_Shading(pdf_context *ctx, pdf_dict *shading, pdf_dict *page_dict, int *num_spots)
-{
-    int code;
-    pdf_obj *o = NULL;
-
-    code = pdfi_dict_knownget(ctx, shading, "ColorSpace", (pdf_obj **)&o);
-    if (code > 0) {
-        code = pdfi_check_ColorSpace_for_spots(ctx, o, shading, page_dict, num_spots);
-        pdfi_countdown(o);
-        return code;
-    }
-    return 0;
-}
-
-/*
- * Check the Resources dictionary Shading entry.
- */
-static int pdfi_check_Shading_dict(pdf_context *ctx, pdf_dict *shading_dict, pdf_dict *page_dict, int *num_spots)
-{
-    int code, i, index;
-    pdf_obj *Key = NULL, *Value = NULL;
-
-    if (pdfi_dict_entries(shading_dict) > 0) {
-        code = pdfi_loop_detector_mark(ctx); /* Mark the start of the Shading dictionary loop */
-        if (code < 0)
-            return code;
-
-        code = pdfi_dict_first(ctx, shading_dict, &Key, &Value, (void *)&index);
-        if (code < 0 || Value->type != PDF_DICT)
-            goto error1;
-
-        i = 1;
-        do {
-            code = pdfi_check_Shading(ctx, (pdf_dict *)Value, page_dict, num_spots);
-            if (code < 0)
-                goto error2;
-
-            pdfi_countdown(Key);
-            Key = NULL;
-            pdfi_countdown(Value);
-            Value = NULL;
-
-            (void)pdfi_loop_detector_cleartomark(ctx); /* Clear to the mark for the Shading dictionary loop */
-
-            code = pdfi_loop_detector_mark(ctx); /* Mark the new start of the Shading dictionary loop */
-            if (code < 0)
-                goto error1;
-
-            do {
-                if (i++ >= pdfi_dict_entries(shading_dict)) {
-                    code = 0;
-                    goto transparency_exit;
-                }
-
-                code = pdfi_dict_next(ctx, shading_dict, &Key, &Value, (void *)&index);
-                if (code == 0 && Value->type == PDF_DICT)
-                    break;
-                pdfi_countdown(Key);
-                Key = NULL;
-                pdfi_countdown(Value);
-                Value = NULL;
-            } while(1);
-        }while (1);
-    }
-    return 0;
-
-transparency_exit:
-error2:
-    pdfi_countdown(Key);
-    pdfi_countdown(Value);
-
-error1:
-    (void)pdfi_loop_detector_cleartomark(ctx); /* Clear to the mark for the current resource loop */
-    return code;
-}
-
-/*
- * This routine checks an XObject to see if it contains any spot
- * colour definitions, or transparency usage.
- */
-static int pdfi_check_XObject(pdf_context *ctx, pdf_dict *xobject, pdf_dict *page_dict, bool *transparent, int *num_spots)
-{
-    int code = 0;
-    pdf_name *n = NULL;
-    bool known = false;
-    double f;
-
-    code = pdfi_dict_get_type(ctx, xobject, "Subtype", PDF_NAME, (pdf_obj **)&n);
-    if (code >= 0) {
-        if (pdfi_name_is((const pdf_name *)n, "Image")) {
-            pdf_obj *CS = NULL;
-
-            pdfi_countdown(n);
-            n = NULL;
-            code = pdfi_dict_known(xobject, "SMask", &known);
-            if (code >= 0) {
-                if (known == true) {
-                    *transparent = true;
-                    if (num_spots == NULL)
-                        goto transparency_exit;
-                }
-                code = pdfi_dict_knownget_number(ctx, xobject, "SMaskInData", &f);
-                if (code > 0) {
-                    code = 0;
-                    if (f != 0.0)
-                        *transparent = true;
-                    if (num_spots == NULL)
-                        goto transparency_exit;
-                }
-                /* Check the image dictionary for a ColorSpace entry, if we are checking spot names */
-                if (num_spots) {
-                    code = pdfi_dict_knownget(ctx, xobject, "ColorSpace", (pdf_obj **)&CS);
-                    if (code > 0) {
-                        /* We don't care if there's an error here, it'll be picked up if we use the ColorSpace later */
-                        (void)pdfi_check_ColorSpace_for_spots(ctx, CS, xobject, page_dict, num_spots);
-                        pdfi_countdown(CS);
-                    }
-                }
-            }
-        } else {
-            if (pdfi_name_is((const pdf_name *)n, "Form")) {
-                pdf_dict *group_dict = NULL, *resource_dict = NULL;
-                pdf_obj *CS = NULL;
-
-                pdfi_countdown(n);
-                code = pdfi_dict_knownget_type(ctx, xobject, "Group", PDF_DICT, (pdf_obj **)&group_dict);
-                if (code > 0) {
-                    *transparent = true;
-                    if (num_spots == NULL) {
-                        pdfi_countdown(group_dict);
-                        goto transparency_exit;
-                    }
-
-                    /* Start a new loop detector group to avoid this being detected in the Resources check below */
-                    code = pdfi_loop_detector_mark(ctx); /* Mark the start of the XObject dictionary loop */
-                    if (code > 0) {
-                        code = pdfi_dict_knownget(ctx, group_dict, "CS", &CS);
-                        if (code > 0)
-                            /* We don't care if there's an error here, it'll be picked up if we use the ColorSpace later */
-                            (void)pdfi_check_ColorSpace_for_spots(ctx, CS, group_dict, page_dict, num_spots);
-                    }
-                    pdfi_countdown(group_dict);
-                    pdfi_countdown(CS);
-                    (void)pdfi_loop_detector_cleartomark(ctx); /* Clear to the mark for the XObject dictionary loop */
-                }
-
-                code = pdfi_dict_knownget_type(ctx, xobject, "Resources", PDF_DICT, (pdf_obj **)&resource_dict);
-                if (code > 0) {
-                    code = pdfi_check_Resources_for_transparency(ctx, resource_dict, page_dict, transparent, num_spots);
-                    pdfi_countdown(resource_dict);
-                    if (code < 0)
-                        goto transparency_exit;
-                }
-            } else
-                pdfi_countdown(n);
-        }
-    }
-
-    return 0;
-
-transparency_exit:
-    return code;
-}
-
-/*
- * Check the Resources dictionary XObject entry.
- */
-static int pdfi_check_XObject_dict(pdf_context *ctx, pdf_dict *xobject_dict, pdf_dict *page_dict, bool *transparent, int *num_spots)
-{
-    int code, i, index;
-    pdf_obj *Key = NULL, *Value = NULL; //, *o = NULL;
-
-    if (pdfi_dict_entries(xobject_dict) > 0) {
-        code = pdfi_loop_detector_mark(ctx); /* Mark the start of the XObject dictionary loop */
-        if (code < 0)
-            return code;
-
-        code = pdfi_dict_first(ctx, xobject_dict, &Key, &Value, (void *)&index);
-        if (code < 0 || Value->type != PDF_DICT)
-            goto error1;
-
-        i = 1;
-        do {
-            code = pdfi_check_XObject(ctx, (pdf_dict *)Value, page_dict, transparent, num_spots);
-            if (code < 0)
-                goto error2;
-
-            (void)pdfi_loop_detector_cleartomark(ctx); /* Clear to the mark for the XObject dictionary loop */
-
-            code = pdfi_loop_detector_mark(ctx); /* Mark the new start of the XObject dictionary loop */
-            if (code < 0)
-                goto error1;
-
-            pdfi_countdown(Key);
-            Key = NULL;
-            pdfi_countdown(Value);
-            Value = NULL;
-
-            do {
-                if (i++ >= pdfi_dict_entries(xobject_dict)) {
-                    code = 0;
-                    goto transparency_exit;
-                }
-
-                code = pdfi_dict_next(ctx, xobject_dict, &Key, &Value, (void *)&index);
-                if (code == 0 && Value->type == PDF_DICT)
-                    break;
-                pdfi_countdown(Key);
-                Key = NULL;
-                pdfi_countdown(Value);
-                Value = NULL;
-            } while(1);
-        }while(1);
-    }
-    return 0;
-
-transparency_exit:
-error2:
-    pdfi_countdown(Key);
-    pdfi_countdown(Value);
-
-error1:
-    (void)pdfi_loop_detector_cleartomark(ctx); /* Clear to the mark for the current resource loop */
-    return code;
-}
-
-/*
- * This routine checks an ExtGState dictionary to see if it contains any spot
- * colour definitions, or transparency usage.
- */
-static int pdfi_check_ExtGState(pdf_context *ctx, pdf_dict *extgstate_dict, pdf_dict *page_dict, bool *transparent, int *num_spots)
-{
-    int code;
-    pdf_obj *o = NULL;
-    double f;
-
-    if (pdfi_dict_entries(extgstate_dict) > 0) {
-        /* Check SMask first, because if we test spot colours first we can exit as
-         * soon as we detect transparency.
-         */
-        code = pdfi_dict_knownget(ctx, extgstate_dict, "SMask", &o);
-        if (code > 0) {
-            if (o->type == PDF_NAME) {
-                if (!pdfi_name_is((pdf_name *)o, "None")) {
-                    pdfi_countdown(o);
-                    *transparent = true;
-                    return 0;
-                }
-            } else {
-                if (o->type == PDF_DICT) {
-                    pdf_obj *G = NULL;
-
-                    *transparent = true;
-
-                    if (num_spots != NULL) {
-                        /* Check if the SMask has a /G (Group) */
-                        code = pdfi_dict_knownget(ctx, (pdf_dict *)o, "G", &G);
-                        if (code > 0) {
-                            code = pdfi_check_XObject(ctx, (pdf_dict *)G, page_dict, transparent, num_spots);
-                            pdfi_countdown(G);
-                        }
-                    }
-                    pdfi_countdown(o);
-                    return code;
-                }
-            }
-        }
-        pdfi_countdown(o);
-        o = NULL;
-
-        code = pdfi_dict_knownget_type(ctx, extgstate_dict, "BM", PDF_NAME, &o);
-        if (code > 0) {
-            if (!pdfi_name_is((pdf_name *)o, "Normal")) {
-                if (!pdfi_name_is((pdf_name *)o, "Compatible")) {
-                    pdfi_countdown(o);
-                    *transparent = true;
-                    return 0;
-                }
-            }
-        }
-        pdfi_countdown(o);
-        o = NULL;
-
-        code = pdfi_dict_knownget_number(ctx, extgstate_dict, "CA", &f);
-        if (code > 0) {
-            if (f != 1.0) {
-                *transparent = true;
-                return 0;
-            }
-        }
-
-        code = pdfi_dict_knownget_number(ctx, extgstate_dict, "ca", &f);
-        if (code > 0) {
-            if (f != 1.0) {
-                *transparent = true;
-                return 0;
-            }
-        }
-    }
-    return 0;
-}
-
-/*
- * Check the Resources dictionary ExtGState entry.
- */
-static int pdfi_check_ExtGState_dict(pdf_context *ctx, pdf_dict *extgstate_dict, pdf_dict *page_dict, bool *transparent, int *num_spots)
-{
-    int code, i, index;
-    pdf_obj *Key = NULL, *Value = NULL;
-
-    if (pdfi_dict_entries(extgstate_dict) > 0) {
-        code = pdfi_loop_detector_mark(ctx); /* Mark the start of the ColorSpace dictionary loop */
-        if (code < 0)
-            return code;
-
-        code = pdfi_dict_first(ctx, extgstate_dict, &Key, &Value, (void *)&index);
-        if (code < 0)
-            goto error1;
-
-        i = 1;
-        do {
-
-            (void)pdfi_check_ExtGState(ctx, (pdf_dict *)Value, page_dict, transparent, num_spots);
-            if (*transparent == true && num_spots == NULL)
-                goto transparency_exit;
-
-            pdfi_countdown(Key);
-            Key = NULL;
-            pdfi_countdown(Value);
-            Value = NULL;
-
-            (void)pdfi_loop_detector_cleartomark(ctx); /* Clear to the mark for the ExtGState dictionary loop */
-
-            code = pdfi_loop_detector_mark(ctx); /* Mark the new start of the ExtGState dictionary loop */
-            if (code < 0)
-                goto error1;
-
-            do {
-                if (i++ >= pdfi_dict_entries(extgstate_dict)) {
-                    code = 0;
-                    goto transparency_exit;
-                }
-
-                code = pdfi_dict_next(ctx, extgstate_dict, &Key, &Value, (void *)&index);
-                if (code == 0 && Value->type == PDF_DICT)
-                    break;
-                pdfi_countdown(Key);
-                Key = NULL;
-                pdfi_countdown(Value);
-                Value = NULL;
-            } while(1);
-        }while (1);
-    }
-    return 0;
-
-transparency_exit:
-    pdfi_countdown(Key);
-    pdfi_countdown(Value);
-
-error1:
-    (void)pdfi_loop_detector_cleartomark(ctx); /* Clear to the mark for the current resource loop */
-    return code;
-}
-
-/*
- * This routine checks a Pattern dictionary to see if it contains any spot
- * colour definitions, or transparency usage.
- */
-int pdfi_check_Pattern(pdf_context *ctx, pdf_dict *pattern, pdf_dict *page_dict, bool *transparent, int *num_spots)
-{
-    int code = 0;
-    pdf_obj *o = NULL;
-
-    if (num_spots != NULL) {
-        code = pdfi_dict_knownget_type(ctx, pattern, "Shading", PDF_DICT, &o);
-        if (code > 0)
-            (void)pdfi_check_Shading(ctx, (pdf_dict *)o, page_dict, num_spots);
-        pdfi_countdown(o);
-        o = NULL;
-    }
-
-    code = pdfi_dict_knownget_type(ctx, pattern, "Resources", PDF_DICT, &o);
-    if (code > 0)
-        (void)pdfi_check_Resources_for_transparency(ctx, (pdf_dict *)o, page_dict, transparent, num_spots);
-    pdfi_countdown(o);
-    o = NULL;
-    if (*transparent == true && num_spots == NULL)
-        goto transparency_exit;
-
-    code = pdfi_dict_knownget_type(ctx, pattern, "ExtGState", PDF_DICT, &o);
-    if (code > 0)
-        (void)pdfi_check_ExtGState(ctx, (pdf_dict *)o, page_dict, transparent, num_spots);
-    pdfi_countdown(o);
-    o = NULL;
-
-transparency_exit:
-    return 0;
-}
-
-/*
- * Check the Resources dictionary Pattern entry.
- */
-static int pdfi_check_Pattern_dict(pdf_context *ctx, pdf_dict *pattern_dict, pdf_dict *page_dict, bool *transparent, int *num_spots)
-{
-    int code, i, index;
-    pdf_obj *Key = NULL, *Value = NULL;
-
-    if (pdfi_dict_entries(pattern_dict) > 0) {
-        code = pdfi_loop_detector_mark(ctx); /* Mark the start of the Pattern dictionary loop */
-        if (code < 0)
-            return code;
-
-        code = pdfi_dict_first(ctx, pattern_dict, &Key, &Value, (void *)&index);
-        if (code < 0)
-            goto error1;
-
-        if (Value->type != PDF_DICT)
-            goto transparency_exit;
-
-        i = 1;
-        do {
-            code = pdfi_check_Pattern(ctx, (pdf_dict *)Value, page_dict, transparent, num_spots);
-            if (code < 0)
-                goto transparency_exit;
-
-            pdfi_countdown(Key);
-            Key = NULL;
-            pdfi_countdown(Value);
-            Value = NULL;
-            (void)pdfi_loop_detector_cleartomark(ctx); /* Clear to the mark for the Shading dictionary loop */
-
-            code = pdfi_loop_detector_mark(ctx); /* Mark the new start of the Shading dictionary loop */
-            if (code < 0)
-                goto error1;
-
-            do {
-                if (i++ >= pdfi_dict_entries(pattern_dict)) {
-                    code = 0;
-                    goto transparency_exit;
-                }
-
-                code = pdfi_dict_next(ctx, pattern_dict, &Key, &Value, (void *)&index);
-                if (code == 0 && Value->type == PDF_DICT)
-                    break;
-                pdfi_countdown(Key);
-                Key = NULL;
-                pdfi_countdown(Value);
-                Value = NULL;
-            } while(1);
-        }while (1);
-    }
-    return 0;
-
-transparency_exit:
-    pdfi_countdown(Key);
-    pdfi_countdown(Value);
-
-error1:
-    (void)pdfi_loop_detector_cleartomark(ctx); /* Clear to the mark for the current resource loop */
-    return code;
-}
-
-/*
- * This routine checks a Font dictionary to see if it contains any spot
- * colour definitions, or transparency usage.
- */
-static int pdfi_check_Font(pdf_context *ctx, pdf_dict *font, pdf_dict *page_dict, bool *transparent, int *num_spots)
-{
-    int code = 0;
-    pdf_obj *o = NULL;
-
-    code = pdfi_dict_knownget_type(ctx, font, "Subtype", PDF_NAME, &o);
-    if (code > 0) {
-        if (pdfi_name_is((pdf_name *)o, "Type3")) {
-            pdfi_countdown(o);
-            o = NULL;
-
-            code = pdfi_dict_knownget_type(ctx, font, "Resources", PDF_DICT, &o);
-            if (code > 0)
-                (void)pdfi_check_Resources_for_transparency(ctx, (pdf_dict *)o, page_dict, transparent, num_spots);
-        }
-    }
-    pdfi_countdown(o);
-    o = NULL;
-
-    return 0;
-}
-
-/*
- * Check the Resources dictionary Font entry.
- */
-static int pdfi_check_Font_dict(pdf_context *ctx, pdf_dict *font_dict, pdf_dict *page_dict, bool *transparent, int *num_spots)
-{
-    int code, i, index;
-    pdf_obj *Key = NULL, *Value = NULL;
-
-    if (pdfi_dict_entries(font_dict) > 0) {
-        code = pdfi_loop_detector_mark(ctx); /* Mark the start of the Font dictionary loop */
-        if (code < 0)
-            return code;
-
-        code = pdfi_dict_first(ctx, font_dict, &Key, &Value, (void *)&index);
-        if (code < 0)
-            goto error1;
-
-        i = 1;
-        do {
-            code = pdfi_check_Font(ctx, (pdf_dict *)Value, page_dict, transparent, num_spots);
-
-            pdfi_countdown(Key);
-            Key = NULL;
-            pdfi_countdown(Value);
-            Value = NULL;
-
-            (void)pdfi_loop_detector_cleartomark(ctx); /* Clear to the mark for the Font dictionary loop */
-
-            code = pdfi_loop_detector_mark(ctx); /* Mark the new start of the Font dictionary loop */
-            if (code < 0)
-                goto error1;
-
-            do {
-                if (i++ >= pdfi_dict_entries(font_dict)) {
-                    code = 0;
-                    goto transparency_exit;
-                }
-
-                code = pdfi_dict_next(ctx, font_dict, &Key, &Value, (void *)&index);
-                if (code == 0 && Value->type == PDF_DICT)
-                    break;
-                pdfi_countdown(Key);
-                Key = NULL;
-                pdfi_countdown(Value);
-                Value = NULL;
-            } while(1);
-        }while (1);
-    }
-    return 0;
-
-transparency_exit:
-    pdfi_countdown(Key);
-    pdfi_countdown(Value);
-
-error1:
-    (void)pdfi_loop_detector_cleartomark(ctx); /* Clear to the mark for the current resource loop */
-    return code;
-}
-
-static int pdfi_check_Resources_for_transparency(pdf_context *ctx, pdf_dict *Resources_dict, pdf_dict *page_dict, bool *transparent, int *num_spots)
-{
-    int code;
-    pdf_obj *d = NULL;
-
-    /* First up, check any colour spaces, for new spot colours.
-     * We only do this if asked because its expensive. num_spots being NULL
-     * means we aren't interested in spot colours (not a DeviceN or Separation device)
-     */
-    if (num_spots != NULL) {
-        code = pdfi_dict_knownget_type(ctx, Resources_dict, "ColorSpace", PDF_DICT, &d);
-        if (code > 0)
-            (void)pdfi_check_ColorSpace_dict(ctx, (pdf_dict *)d, page_dict, num_spots);
-
-        pdfi_countdown(d);
-        d = NULL;
-
-        code = pdfi_dict_knownget_type(ctx, Resources_dict, "Shading", PDF_DICT, &d);
-        if (code > 0)
-            (void)pdfi_check_Shading_dict(ctx, (pdf_dict *)d, page_dict, num_spots);
-        pdfi_countdown(d);
-        d = NULL;
-    }
-
-    code = pdfi_dict_knownget_type(ctx, Resources_dict, "XObject", PDF_DICT, &d);
-    if (code > 0)
-        (void)pdfi_check_XObject_dict(ctx, (pdf_dict *)d, page_dict, transparent, num_spots);
-    pdfi_countdown(d);
-    d = NULL;
-
-    code = pdfi_dict_knownget_type(ctx, Resources_dict, "Pattern", PDF_DICT, &d);
-    if (code > 0)
-        (void)pdfi_check_Pattern_dict(ctx, (pdf_dict *)d, page_dict, transparent, num_spots);
-    pdfi_countdown(d);
-    d = NULL;
-
-    code = pdfi_dict_knownget_type(ctx, Resources_dict, "Font", PDF_DICT, &d);
-    if (code > 0)
-        (void)pdfi_check_Font_dict(ctx, (pdf_dict *)d, page_dict, transparent, num_spots);
-    /* From this point onwards, if we detect transparency (or have already detected it) we
-     * can exit, we have already counted up any spot colours.
-     */
-    pdfi_countdown(d);
-    d = NULL;
-
-    code = pdfi_dict_knownget_type(ctx, Resources_dict, "ExtGState", PDF_DICT, &d);
-    if (code > 0)
-        (void)pdfi_check_ExtGState_dict(ctx, (pdf_dict *)d, page_dict, transparent, num_spots);
-    pdfi_countdown(d);
-    d = NULL;
-
-    return 0;
-}
-
-static int pdfi_check_annot_for_transparency(pdf_context *ctx, pdf_dict *annot, pdf_dict *page_dict, bool *transparent, int *num_spots)
-{
-    int code;
-    pdf_name *n;
-    pdf_dict *ap = NULL, *N = NULL, *Resources = NULL;
-    double f;
-
-    /* Check #1 Does the (Normal) Appearnce stream use any Resources which include transparency.
-     * We check this first, because this also checks for spot colour spaces. Once we've done that we
-     * can exit the checks as soon as we detect transparency.
-     */
-    code = pdfi_dict_knownget_type(ctx, annot, "AP", PDF_DICT, (pdf_obj **)&ap);
-    if (code > 0)
-    {
-        code = pdfi_dict_knownget_type(ctx, ap, "N", PDF_DICT, (pdf_obj **)&N);
-        if (code > 0) {
-            code = pdfi_dict_knownget_type(ctx, N, "Resources", PDF_DICT, (pdf_obj **)&Resources);
-            if (code > 0)
-                code = pdfi_check_Resources_for_transparency(ctx, (pdf_dict *)Resources, page_dict, transparent, num_spots);
-        }
-    }
-    pdfi_countdown(ap);
-    pdfi_countdown(N);
-    pdfi_countdown(Resources);
-    if (code < 0)
-        return code;
-    /* We've checked the Resources, and nothing else in an annotation can define spot colours, so
-     * if we detected transparency in the Resources we need not check further.
-     */
-    if (*transparent == true)
-        return 0;
-
-    code = pdfi_dict_get_type(ctx, annot, "Subtype", PDF_NAME, (pdf_obj **)&n);
-    if (code < 0) {
-        if (ctx->pdfstoponerror)
-            return code;
-    } else {
-        /* Check #2, Highlight annotations are always preformed with transparency */
-        if (pdfi_name_is((const pdf_name *)n, "Highlight")) {
-            pdfi_countdown(n);
-            *transparent = true;
-            return 0;
-        }
-        pdfi_countdown(n);
-        n = NULL;
-
-        /* Check #3 Blend Mode (BM) not being 'Normal' or 'Compatible' */
-        code = pdfi_dict_knownget_type(ctx, annot, "BM", PDF_NAME, (pdf_obj **)&n);
-        if (code > 0) {
-            if (!pdfi_name_is((const pdf_name *)n, "Normal")) {
-                if (!pdfi_name_is((const pdf_name *)n, "Compatible")) {
-                    pdfi_countdown(n);
-                    *transparent = true;
-                    return 0;
-                }
-            }
-            code = 0;
-        }
-        pdfi_countdown(n);
-        if (code < 0)
-            return code;
-
-        /* Check #4 stroke constant alpha (CA) is not 1 (100% opaque) */
-        code = pdfi_dict_knownget_number(ctx, annot, "CA", &f);
-        if (code > 0) {
-            if (f != 1.0) {
-                *transparent = true;
-                return 0;
-            }
-        }
-        if (code < 0)
-            return code;
-
-        /* Check #5 non-stroke constant alpha (ca) is not 1 (100% opaque) */
-        code = pdfi_dict_knownget_number(ctx, annot, "ca", &f);
-        if (code > 0) {
-            if (f != 1.0) {
-                *transparent = true;
-                return 0;
-            }
-        }
-        if (code < 0)
-            return code;
-    }
-
-    return 0;
-}
-
-static int pdfi_check_Annots_for_transparency(pdf_context *ctx, pdf_array *annots_array, pdf_dict *page_dict, bool *transparent, int *num_spots)
-{
-    int i, code = 0;
-    pdf_dict *annot = NULL;
-
-    for (i=0; i < pdfi_array_size(annots_array); i++) {
-        code = pdfi_array_get_type(ctx, annots_array, (uint64_t)i, PDF_DICT, (pdf_obj **)&annot);
-        if (code > 0) {
-            code = pdfi_check_annot_for_transparency(ctx, annot, page_dict, transparent, num_spots);
-            if (code < 0 && ctx->pdfstoponerror)
-                goto exit;
-
-            /* If we've found transparency, and don't need to continue checkign for spot colours
-             * just exit as fast as possible.
-             */
-            if (*transparent == true && num_spots == NULL)
-                goto exit;
-
-            pdfi_countdown(annot);
-            annot = NULL;
-        }
-    }
-exit:
-    pdfi_countdown(annot);
-    return code;
-}
-
-/* From the original PDF interpreter written in PostScript:
- * Note: we deliberately don't check to see whether a Group is defined,
- * because Adobe Illustrator 10 (and possibly other applications) define
- * a page-level group whether transparency is actually used or not.
- * Ignoring the presence of Group is justified because, in the absence
- * of any other transparency features, they have no effect.
- */
-static int pdfi_check_page_transparency(pdf_context *ctx, pdf_dict *page_dict, bool *transparent, int *spots)
-{
-    int code;
-    pdf_obj *d = NULL;
-    int num_spots = 0;
-    pdf_dict *group_dict = NULL;
-
-    /* Note that we don't reset 'spots' to 0 because these accumulate across pages */
-    *transparent = false;
-
-    ctx->spot_capable_device = false;
-    gs_c_param_list_read(&ctx->pdfi_param_list);
-    code = param_read_int((gs_param_list *)&ctx->pdfi_param_list, "PageSpotColors", &ctx->spot_capable_device);
-    if (code < 0)
-        return code;
-    if (code > 0)
-        ctx->spot_capable_device = 0;
-    else
-        ctx->spot_capable_device = 1;
-
-    /* Check if the page dictionary has a page Group entry */
-    code = pdfi_dict_knownget_type(ctx, page_dict, "Group", PDF_DICT, (pdf_obj **)&group_dict);
-    if (code > 0) {
-        pdf_obj *CS = NULL;
-
-        /* Page group means the page is transparent but we ignore it for the purposes
-         * of transparency detection. See above.
-         */
-        if (ctx->spot_capable_device) {
-            /* Check the Group to see if it has a ColorSpace (CS) and if it
-             * does whether it has any spot colours */
-            code = pdfi_dict_knownget(ctx, group_dict, "CS", &CS);
-            if (code > 0) {
-                code = pdfi_check_ColorSpace_for_spots(ctx, CS, group_dict, page_dict, spots);
-                if (code < 0 && ctx->pdfstoponerror) {
-                    pdfi_countdown(CS);
-                    pdfi_countdown(group_dict);
-                    pdfi_countdown(ctx->SpotNames);
-                    return code;
-                }
-                pdfi_countdown(CS);
-            }
-        }
-        pdfi_countdown(group_dict);
-    }
-
-    /* Now check any Resources dictionary in the Page dictionary */
-    code = pdfi_dict_get_type(ctx, page_dict, "Resources", PDF_DICT, &d);
-    if (code >= 0) {
-        if (ctx->spot_capable_device)
-            code = pdfi_check_Resources_for_transparency(ctx, (pdf_dict *)d, page_dict, transparent, &num_spots);
-        else
-            code = pdfi_check_Resources_for_transparency(ctx, (pdf_dict *)d, page_dict, transparent, NULL);
-        pdfi_countdown(d);
-        if (code < 0)
-            return code;
-    }
-    if (code < 0 && code != gs_error_undefined && ctx->pdfstoponerror)
-        return code;
-
-    /* If we are drawing Annotations, check to see if the page uses any Annots */
-    if (ctx->showannots) {
-        code = pdfi_dict_get_type(ctx, page_dict, "Annots", PDF_ARRAY, &d);
-        if (code >= 0) {
-            if (ctx->spot_capable_device)
-                code = pdfi_check_Annots_for_transparency(ctx, (pdf_array *)d, page_dict, transparent, &num_spots);
-            else
-                code = pdfi_check_Annots_for_transparency(ctx, (pdf_array *)d, page_dict, transparent, NULL);
-            pdfi_countdown(d);
-            if (code < 0)
-                return code;
-        }
-        if (code < 0 && code != gs_error_undefined && ctx->pdfstoponerror)
-            return code;
-    }
-
-    if (ctx->spot_capable_device)
-        *spots += num_spots;
-    else
-        *spots = 0;
-
-    return 0;
-}
-
-static int pdfi_check_transparency_spots(pdf_context *ctx)
-{
-    int code = 0;
-
-    /* Loop round all the pages looking for spot colours and transparency. We only check
-     * for spot colours if the device is capable of spot colours (the code checks). We
-     * only store the transparency setting if NOTRANSPARENCY is not set
-     */
-    if (ctx->num_pages) {
-        pdf_dict *page_dict = NULL;
-        uint64_t page_offset = 0;
-        bool uses_transparency = false;
-        int spots = 0;
-        uint64_t ix;
-
-        int bytes = (int)ceil((float)ctx->num_pages / 8.0f);
-        ctx->PageTransparencyArray = (char *)gs_alloc_bytes(ctx->memory, bytes, "pdfi_process_file, allocate page transparency tracking array");
-        memset(ctx->PageTransparencyArray, 0x00, bytes);
-
-        code = pdfi_alloc_object(ctx, PDF_DICT, 32, (pdf_obj **)&ctx->SpotNames);
-        if (code < 0)
-            goto exit;
-
-        pdfi_countup(ctx->SpotNames);
-
-        for (ix=0;ix < ctx->num_pages;ix++) {
-            if (ctx->pdfdebug)
-                dmprintf1(ctx->memory, "%% Checking Page %"PRIi64" for transparency and spot plates\n", ix + 1);
-
-            uses_transparency = false;
-
-            /* Get the page dictionary */
-            code = pdfi_loop_detector_mark(ctx);
-            if (code < 0)
-                goto exit;
-
-            code = pdfi_loop_detector_add_object(ctx, ctx->Pages->object_num);
-            if (code < 0) {
-                pdfi_loop_detector_cleartomark(ctx);
-                goto exit;
-            }
-
-            page_offset = 0;
-            code = pdfi_get_page_dict(ctx, ctx->Pages, ix, &page_offset, &page_dict, NULL);
-            pdfi_loop_detector_cleartomark(ctx);
-            if (code < 0) {
-                if (code == gs_error_VMerror || ctx->pdfstoponerror)
-                    goto exit;
-                return 0;
-            }
-
-            if (code > 0) {
-                /* This can happen if the number of declared pages (/Count) is larger than the number of pages in the Pages array
-                 * We'll ignore that for the purposes of transparency checking. If the user tries to render this
-                 * page it'll fail in the page rendering code.
-                 */
-                pdfi_countdown(page_dict);
-                page_dict = NULL;
-                break;
-            }
-
-            /* Check the page dictionary for spots and transparency */
-            code = pdfi_check_page_transparency(ctx, page_dict, &uses_transparency, &spots);
-            if (code < 0) {
-                pdfi_countdown(ctx->SpotNames);
-                pdfi_countdown(page_dict);
-                ctx->SpotNames = NULL;
-                goto exit;
-            }
-            if (uses_transparency && !ctx->notransparency) {
-                uint64_t index = ix >> 3;
-                char value = 0x80 >> (ix % 8);
-
-                ctx->PageTransparencyArray[index] |= value;
-            }
-            pdfi_countdown(page_dict);
-            page_dict = NULL;
-        }
-
-        pdfi_countdown(ctx->SpotNames);
-        ctx->SpotNames = NULL;
-
-        /* If there are spot colours (and by inference, the device renders spot plates) then
-         * send the number of Spots to the device, so it can setup correctly.
-         */
-        if (spots > 0) {
-            gs_c_param_list_write(&ctx->pdfi_param_list, ctx->memory);
-            param_write_int((gs_param_list *)&ctx->pdfi_param_list, "PageSpotColors", &spots);
-            gs_c_param_list_read(&ctx->pdfi_param_list);
-            code = gs_putdeviceparams(ctx->pgs->device, (gs_param_list *)&ctx->pdfi_param_list);
-            if (code > 0) {
-                /* The device was closed, we need to reopen it */
-                code = gs_setdevice_no_erase(ctx->pgs, ctx->pgs->device);
-                if (code < 0) {
-                    if (uses_transparency)
-                        (void)gs_abort_pdf14trans_device(ctx->pgs);
-                    pdfi_countdown(ctx->SpotNames);
-                    pdfi_countdown(page_dict);
-                    goto exit;
-                }
-                gs_erasepage(ctx->pgs);
-            }
-        }
-    }
-exit:
-    return code;
-}
-
-static int pdfi_set_media_size(pdf_context *ctx, pdf_dict *page_dict)
-{
-    gs_c_param_list list;
-    gs_param_float_array fa;
-    pdf_array *a = NULL, *default_media = NULL;
-    float fv[2];
-    double d[4];
-    int code;
-    uint64_t i;
-    int64_t rotate = 0;
-
-    gs_c_param_list_write(&list, ctx->memory);
-
-    code = pdfi_dict_get_type(ctx, page_dict, "MediaBox", PDF_ARRAY, (pdf_obj **)&default_media);
-    if (code < 0) {
-        code = gs_erasepage(ctx->pgs);
-        return 0;
-    }
-
-    if (ctx->usecropbox) {
-        if (a != NULL)
-            pdfi_countdown(a);
-        (void)pdfi_dict_get_type(ctx, page_dict, "CropBox", PDF_ARRAY, (pdf_obj **)&a);
-    }
-    if (ctx->useartbox) {
-        if (a != NULL)
-            pdfi_countdown(a);
-        (void)pdfi_dict_get_type(ctx, page_dict, "ArtBox", PDF_ARRAY, (pdf_obj **)&a);
-    }
-    if (ctx->usebleedbox) {
-        if (a != NULL)
-            pdfi_countdown(a);
-        (void)pdfi_dict_get_type(ctx, page_dict, "BleedBox", PDF_ARRAY, (pdf_obj **)&a);
-    }
-    if (ctx->usetrimbox) {
-        if (a != NULL)
-            pdfi_countdown(a);
-        (void)pdfi_dict_get_type(ctx, page_dict, "MediaBox", PDF_ARRAY, (pdf_obj **)&a);
-    }
-    if (a == NULL)
-        a = default_media;
-
-    for (i=0;i<4;i++) {
-        code = pdfi_array_get_number(ctx, a, i, &d[i]);
-    }
-    pdfi_countdown(a);
-
-    normalize_rectangle(d);
-    memcpy(ctx->PageSize, d, 4 * sizeof(double));
-
-    code = pdfi_dict_get_int(ctx, page_dict, "Rotate", &rotate);
-
-    rotate = rotate % 360;
-
-    switch(rotate) {
-        default:
-        case 0:
-        case 360:
-        case -180:
-        case 180:
-            fv[0] = (float)(d[2] - d[0]);
-            fv[1] = (float)(d[3] - d[1]);
-            break;
-        case -90:
-        case 90:
-        case -270:
-        case 270:
-            fv[1] = (float)(d[2] - d[0]);
-            fv[0] = (float)(d[3] - d[1]);
-            break;
-    }
-
-    fa.persistent = false;
-    fa.data = fv;
-    fa.size = 2;
-
-    code = param_write_float_array((gs_param_list *)&list, ".MediaSize", &fa);
-    if (code >= 0)
-    {
-        gx_device *dev = gs_currentdevice(ctx->pgs);
-
-        gs_c_param_list_read(&list);
-        code = gs_putdeviceparams(dev, (gs_param_list *)&list);
-        if (code < 0) {
-            gs_c_param_list_release(&list);
-            return code;
-        }
-    }
-    gs_c_param_list_release(&list);
-
-    gs_initgraphics(ctx->pgs);
-
-    switch(rotate) {
-        case 0:
-            break;
-        case -270:
-        case 90:
-            gs_translate(ctx->pgs, 0, fv[1]);
-            gs_rotate(ctx->pgs, -90);
-            break;
-        case -180:
-        case 180:
-            gs_translate(ctx->pgs, fv[0], fv[1]);
-            gs_rotate(ctx->pgs, 180);
-            break;
-        case -90:
-        case 270:
-            gs_translate(ctx->pgs, fv[0], 0);
-            gs_rotate(ctx->pgs, 90);
-            break;
-        default:
-            break;
-    }
-
-    gs_translate(ctx->pgs, d[0] * -1, d[1] * -1);
-
-    code = gs_erasepage(ctx->pgs);
-    return 0;
-}
+#include "pdf_page.h"
+#include "pdf_check.h"
 
 /*
  * Convenience routine to check if a given string exists in a dictionary
@@ -1429,299 +296,6 @@ static int pdfi_output_page_info(pdf_context *ctx, uint64_t page_num)
     return 0;
 }
 
-static int pdfi_process_page_contents(pdf_context *ctx, pdf_dict *page_dict)
-{
-    int i, code = 0;
-    pdf_obj *o, *o1;
-
-    code = pdfi_dict_get(ctx, page_dict, "Contents", &o);
-    if (code == gs_error_undefined)
-        /* Don't throw an error if there are no contents, just render nothing.... */
-        return 0;
-    if (code < 0)
-        return code;
-
-    if (o->type == PDF_INDIRECT) {
-        if (((pdf_indirect_ref *)o)->ref_object_num == page_dict->object_num)
-            return_error(gs_error_circular_reference);
-
-        code = pdfi_dereference(ctx, ((pdf_indirect_ref *)o)->ref_object_num, ((pdf_indirect_ref *)o)->ref_generation_num, &o1);
-        pdfi_countdown(o);
-        if (code < 0) {
-            if (code == gs_error_VMerror)
-                return code;
-            return 0;
-        }
-        o = o1;
-    }
-
-    code = pdfi_gsave(ctx);
-    if (code < 0) {
-        pdfi_countdown(o);
-        return code;
-    }
-
-    if (o->type == PDF_ARRAY) {
-        pdf_array *a = (pdf_array *)o;
-
-        for (i=0;i < pdfi_array_size(a); i++) {
-            pdf_indirect_ref *r;
-            code = pdfi_array_get_no_deref(ctx, a, i, (pdf_obj **)&r);
-            if (code < 0)
-                goto page_error;
-            if (r->type == PDF_DICT) {
-                code = pdfi_interpret_content_stream(ctx, (pdf_dict *)r, page_dict);
-                pdfi_countdown(r);
-                if (code < 0)
-                    goto page_error;
-            } else {
-                if (r->type != PDF_INDIRECT) {
-                        pdfi_countdown(r);
-                        code = gs_note_error(gs_error_typecheck);
-                        goto page_error;
-                } else {
-                    if (r->ref_object_num == page_dict->object_num) {
-                        pdfi_countdown(r);
-                        code = gs_note_error(gs_error_circular_reference);
-                        goto page_error;
-                    }
-                    code = pdfi_dereference(ctx, r->ref_object_num, r->ref_generation_num, &o1);
-                    pdfi_countdown(r);
-                    if (code < 0) {
-                        if (code != gs_error_VMerror || ctx->pdfstoponerror == false)
-                            code = 0;
-                        goto page_error;
-                    }
-                    if (o1->type != PDF_DICT) {
-                        pdfi_countdown(o1);
-                        code = gs_note_error(gs_error_typecheck);
-                        goto page_error;
-                    }
-                    code = pdfi_interpret_content_stream(ctx, (pdf_dict *)o1, page_dict);
-                    pdfi_countdown(o1);
-                    if (code < 0) {
-                        if (code == gs_error_VMerror || ctx->pdfstoponerror == true)
-                            goto page_error;
-                    }
-                }
-            }
-        }
-    } else {
-        if (o->type == PDF_DICT) {
-            code = pdfi_interpret_content_stream(ctx, (pdf_dict *)o, page_dict);
-        } else {
-            pdfi_countdown(o);
-            return_error(gs_error_typecheck);
-        }
-    }
-page_error:
-    pdfi_grestore(ctx);
-    pdfi_countdown(o);
-    return code;
-}
-
-static int pdfi_render_page(pdf_context *ctx, uint64_t page_num)
-{
-    int code, code1=0;
-    uint64_t page_offset = 0;
-    pdf_dict *page_dict = NULL;
-    bool uses_transparency = false;
-    bool page_group_known = false;
-    int page_index = page_num >> 3;
-    char page_bit = 0x80 >> (page_num % 8);
-    stream_save local_entry_save;
-    pdf_dict *group_dict = NULL;
-
-    if (page_num > ctx->num_pages)
-        return_error(gs_error_rangecheck);
-
-    if (ctx->pdfdebug)
-        dmprintf1(ctx->memory, "%% Processing Page %"PRIi64" content stream\n", page_num + 1);
-
-    code = pdfi_loop_detector_mark(ctx);
-    if (code < 0)
-        return code;
-
-    code = pdfi_loop_detector_add_object(ctx, ctx->Pages->object_num);
-    if (code < 0) {
-        pdfi_loop_detector_cleartomark(ctx);
-        goto exit2;
-    }
-
-    code = pdfi_get_page_dict(ctx, ctx->Pages, page_num, &page_offset, &page_dict, NULL);
-    pdfi_loop_detector_cleartomark(ctx);
-    if (code < 0) {
-        if (code == gs_error_VMerror || ctx->pdfstoponerror)
-            goto exit2;
-        code = 0;
-        goto exit2;
-    }
-
-    if (code > 0) {
-        code = gs_note_error(gs_error_unknownerror);
-        goto exit2;
-    }
-
-    code = pdfi_set_media_size(ctx, page_dict);
-    if (code < 0) {
-        goto exit2;
-    }
-
-    code = pdfi_dict_knownget_type(ctx, page_dict, "Group", PDF_DICT, (pdf_obj **)&group_dict);
-    if (code < 0)
-        goto exit2;
-    if (group_dict != NULL)
-        page_group_known = true;
-
-    pdfi_countdown(ctx->CurrentPageDict);
-    ctx->CurrentPageDict = page_dict;
-    pdfi_countup(ctx->CurrentPageDict);
-
-    code = gs_setstrokeconstantalpha(ctx->pgs, 1.0);
-    code = gs_setfillconstantalpha(ctx->pgs, 1.0);
-    code = gs_setalphaisshape(ctx->pgs, 0);
-    code = gs_setblendmode(ctx->pgs, BLEND_MODE_Compatible);
-    code = gs_settextknockout(ctx->pgs, true);
-    code = gs_settextspacing(ctx->pgs, (double)0.0);
-    code = gs_settextleading(ctx->pgs, (double)0.0);
-    gs_settextrenderingmode(ctx->pgs, 0);
-    code = gs_setwordspacing(ctx->pgs, (double)0.0);
-    code = gs_settexthscaling(ctx->pgs, (double)100.0);
-    ctx->TextBlockDepth = 0;
-
-    if (ctx->pgs->set_transfer.red == 0x00) {
-        ctx->DefaultTransfers[0].proc = gs_identity_transfer;
-        memset(ctx->DefaultTransfers[0].values, 0x00, transfer_map_size * sizeof(frac));
-    } else {
-        ctx->DefaultTransfers[0].proc = ctx->pgs->set_transfer.red->proc;
-        memcpy(ctx->DefaultTransfers[0].values, ctx->pgs->set_transfer.red->values, transfer_map_size * sizeof(frac));
-    }
-    if (ctx->pgs->set_transfer.green == 0x00) {
-        ctx->DefaultTransfers[1].proc = gs_identity_transfer;
-        memset(ctx->DefaultTransfers[1].values, 0x00, transfer_map_size * sizeof(frac));
-    } else {
-        ctx->DefaultTransfers[1].proc = ctx->pgs->set_transfer.green->proc;
-        memcpy(ctx->DefaultTransfers[1].values, ctx->pgs->set_transfer.green->values, transfer_map_size * sizeof(frac));
-    }
-    if (ctx->pgs->set_transfer.blue == 0x00) {
-        ctx->DefaultTransfers[2].proc = gs_identity_transfer;
-        memset(ctx->DefaultTransfers[2].values, 0x00, transfer_map_size * sizeof(frac));
-    } else {
-        ctx->DefaultTransfers[2].proc = ctx->pgs->set_transfer.blue->proc;
-        memcpy(ctx->DefaultTransfers[2].values, ctx->pgs->set_transfer.blue->values, transfer_map_size * sizeof(frac));
-    }
-    if (ctx->pgs->set_transfer.gray == 0x00) {
-        ctx->DefaultTransfers[3].proc = gs_identity_transfer;
-        memset(ctx->DefaultTransfers[3].values, 0x00, transfer_map_size * sizeof(frac));
-    } else {
-        ctx->DefaultTransfers[3].proc = ctx->pgs->set_transfer.gray->proc;
-        memcpy(ctx->DefaultTransfers[3].values, ctx->pgs->set_transfer.gray->values, transfer_map_size * sizeof(frac));
-    }
-    if (ctx->pgs->black_generation == 0x00) {
-        ctx->DefaultBG.proc = gs_identity_transfer;
-        memset(ctx->DefaultBG.values, 0x00, transfer_map_size * sizeof(frac));
-    } else {
-        ctx->DefaultBG.proc = ctx->pgs->black_generation->proc;
-        memcpy(ctx->DefaultBG.values, ctx->pgs->black_generation->values, transfer_map_size * sizeof(frac));
-    }
-    if (ctx->pgs->undercolor_removal == 0x00) {
-        ctx->DefaultUCR.proc = gs_identity_transfer;
-        memset(ctx->DefaultUCR.values, 0x00, transfer_map_size * sizeof(frac));
-    } else {
-        ctx->DefaultUCR.proc = ctx->pgs->undercolor_removal->proc;
-        memcpy(ctx->DefaultUCR.values, ctx->pgs->undercolor_removal->values, transfer_map_size * sizeof(frac));
-    }
-    dbgmprintf1(ctx->memory, "Current page transparency setting is %d\n", ctx->PageTransparencyArray[page_index] & page_bit ? 1 : 0);
-
-    /* Force NOTRANSPARENCY here if required, until we can get it working... */
-    ctx->page_has_transparency = ctx->PageTransparencyArray[page_index] & page_bit ? 1 : 0;
-
-    /* Set whether device needs OP support
-     * This needs to be before transparency device is pushed, if applicable
-     */
-    pdfi_trans_set_needs_OP(ctx);
-    pdfi_oc_init(ctx);
-
-    pdfi_gsave(ctx);
-
-    if (ctx->page_has_transparency) {
-        if (code >= 0) {
-            /* We don't retain the PDF14 device */
-            code = gs_push_pdf14trans_device(ctx->pgs, false, false);
-            if (code >= 0) {
-                if (page_group_known) {
-                    code = pdfi_trans_begin_page_group(ctx, page_dict, group_dict);
-                    /* If setting the page group failed for some reason, abandon the page group, but continue with the page */
-                    if (code < 0)
-                        page_group_known = false;
-                }
-            } else {
-                /* Couldn't push the transparency compositor.
-                 * This is probably fatal, but attempt to recover by abandoning transparency
-                 */
-                ctx->page_has_transparency = uses_transparency = false;
-            }
-        } else {
-            /* Couldn't gsave round the transparency compositor.
-             * This is probably fatal, but attempt to recover by abandoning transparency
-             */
-            ctx->page_has_transparency = uses_transparency = false;
-        }
-    }
-
-    /* Init a base_pgs graphics state for Patterns
-     * (this has to be after transparency device pushed, if applicable)
-     */
-    pdfi_set_DefaultQState(ctx, ctx->pgs);
-
-    /* Save the current stream state, for later cleanup, in a local variable */
-    local_save_stream_state(ctx, &local_entry_save);
-    initialise_stream_save(ctx);
-
-    code = pdfi_process_page_contents(ctx, page_dict);
-
-    /* Put our state back the way it was before we ran the contents
-     * and check if the stream had problems
-     */
-#ifdef PROBE_STREAMS
-    if (ctx->pgs->level > ctx->current_stream_save.gsave_level ||
-        pdfi_count_stack(ctx) > ctx->current_stream_save.stack_count)
-        code = ((pdf_context *)0)->first_page;
-#endif
-
-    cleanup_context_interpretation(ctx, &local_entry_save);
-    local_restore_stream_state(ctx, &local_entry_save);
-
-    if (ctx->page_has_transparency && page_group_known) {
-        code1 = pdfi_trans_end_group(ctx);
-    }
-
-    pdfi_countdown(ctx->CurrentPageDict);
-    ctx->CurrentPageDict = NULL;
-
-    if (ctx->page_has_transparency) {
-        if (code1 < 0) {
-            (void)gs_abort_pdf14trans_device(ctx->pgs);
-            goto exit1;
-        }
-
-        code = gs_pop_pdf14trans_device(ctx->pgs, false);
-        if (code < 0) {
-            goto exit1;
-        }
-    }
-
- exit1:
-    pdfi_grestore(ctx);
- exit2:
-    pdfi_countdown(page_dict);
-    pdfi_countdown(group_dict);
-
-    if (code == 0)
-        code = pl_finish_page(ctx->memory->gs_lib_ctx->top_of_system, ctx->pgs, 1, true);
-    return code;
-}
-
 static void
 pdfi_report_errors(pdf_context *ctx)
 {
@@ -1976,7 +550,7 @@ read_root:
         if (ctx->pdfinfo)
             code = pdfi_output_page_info(ctx, i);
         else
-            code = pdfi_render_page(ctx, i);
+            code = pdfi_page_render(ctx, i);
 
         if (code < 0 && ctx->pdfstoponerror)
             goto exit;
diff --git a/pdf/ghostpdf.h b/pdf/ghostpdf.h
index d8e2651..ac90c60 100644
--- a/pdf/ghostpdf.h
+++ b/pdf/ghostpdf.h
@@ -343,7 +343,4 @@ int pdfi_open_pdf_file(pdf_context *ctx, char *filename);
 int pdfi_process_pdf_file(pdf_context *ctx, char *filename);
 int pdfi_close_pdf_file(pdf_context *ctx);
 
-/* Transparency stuff, should be moved */
-int pdfi_check_Pattern(pdf_context *ctx, pdf_dict *pattern, pdf_dict *page_dict, bool *transparent, int *num_spots);
-
 #endif
diff --git a/pdf/pdf.mak b/pdf/pdf.mak
index a9d0082..b758ca2 100644
--- a/pdf/pdf.mak
+++ b/pdf/pdf.mak
@@ -131,6 +131,9 @@ $(PDFOBJ)pdf_misc.$(OBJ): $(PDFSRC)pdf_misc.c $(PDFINCLUDES) $(PDF_MAK) $(MAKEDI
 $(PDFOBJ)pdf_optcontent.$(OBJ): $(PDFSRC)pdf_optcontent.c $(PDFINCLUDES) $(PDF_MAK) $(MAKEDIRS)
 	$(PDFCCC) $(PDFSRC)pdf_optcontent.c $(PDFO_)pdf_optcontent.$(OBJ)
 
+$(PDFOBJ)pdf_check.$(OBJ): $(PDFSRC)pdf_check.c $(PDFINCLUDES) $(PDF_MAK) $(MAKEDIRS)
+	$(PDFCCC) $(PDFSRC)pdf_check.c $(PDFO_)pdf_check.$(OBJ)
+
 $(PDFGEN)pdfimpl.c: $(PLSRC)plimpl.c $(PDF_MAK) $(MAKEDIRS)
 	$(CP_) $(PLSRC)plimpl.c $(PDFGEN)pdfimpl.c
 
@@ -178,6 +181,7 @@ PDF_OBJS=\
     $(PDFOBJ)pdf_device.$(OBJ)\
     $(PDFOBJ)pdf_misc.$(OBJ)\
     $(PDFOBJ)pdf_optcontent.$(OBJ)\
+    $(PDFOBJ)pdf_check.$(OBJ)\
 
 
 # NB - note this is a bit squirrely.  Right now the pjl interpreter is
diff --git a/pdf/pdf_check.c b/pdf/pdf_check.c
new file mode 100644
index 0000000..ea6bfb1
--- /dev/null
+++ b/pdf/pdf_check.c
@@ -0,0 +1,1043 @@
+/* Copyright (C) 2001-2019 Artifex Software, Inc.
+   All Rights Reserved.
+
+   This software is provided AS-IS with no warranty, either express or
+   implied.
+
+   This software is distributed under license and may not be copied,
+   modified or distributed except as expressly authorized under the terms
+   of the license contained in the file LICENSE in this distribution.
+
+   Refer to licensing information at http://www.artifex.com or contact
+   Artifex Software, Inc.,  1305 Grant Avenue - Suite 200, Novato,
+   CA 94945, U.S.A., +1(415)492-9861, for further information.
+*/
+
+/* Checks for transparency and spots for the PDF interpreter */
+
+#include "pdf_int.h"
+#include "pdf_stack.h"
+#include "pdf_page.h"
+#include "pdf_file.h"
+#include "pdf_dict.h"
+#include "pdf_array.h"
+#include "pdf_loop_detect.h"
+#include "pdf_colour.h"
+#include "pdf_trans.h"
+#include "pdf_gstate.h"
+#include "pdf_misc.h"
+#include "pdf_check.h"
+
+/* This routine is slightly misnamed, as it also checks ColorSpaces for spot colours.
+ * This is done at the page level, so we maintain a dictionary of the spot colours
+ * encountered so far, which we consult before adding any new ones.
+ */
+static int pdfi_check_Resources_for_transparency(pdf_context *ctx, pdf_dict *Resources_dict, pdf_dict *page_dict, bool *transparent, int *num_spots);
+
+/* For performance and resource reasons we do not want to install the transparency blending
+ * compositor unless we need it. Similarly, if a device handles spot colours it can minimise
+ * memory usage if it knows ahead of time how many spot colours there will be.
+ *
+ * The PDF interpreter written in PostScript performed these as two separate tasks, on opening
+ * a PDF file it would count spot colour usage and then for each page it would chek if the page
+ * used any transparency. The code below is used to check for both transparency and spot colours.
+ * If the int pointer to num_spots is NULL then we aren't interested in spot colours (not supported
+ * by the device), if the int pointer to transparent is NULL then we aren't interested in transparency
+ * (-dNOTRANSPARENCY is set).
+ *
+ * Currenlty the code is run when we open the PDF file, the existence of transparency on any given
+ * page is recorded in a bit array for later use. If it turns out that checking every page when we
+ * open the file is a performance burden then we could do it on a per-page basis instead. NB if
+ * the device supports spot colours then we do need to scan the file before starting any page.
+ *
+ * The technique is fairly straight-forward, we start with each page, and open its Resources
+ * dictionary, we then check by type each possible resource. Some resources (eg Pattern, XObject)
+ * can themselves contain Resources, in which case we recursively check that dictionary. Note; not
+ * all Resource types need to be checked for both transparency and spot colours, some types can
+ * only contain one or the other.
+ *
+ * Routines with the name pdfi_check_xxx_dict are intended to check a Resource dictionary entry, this
+ * will be a dictioanry of names and values, where the values are objects of the given Resource type.
+ *
+ */
+
+/*
+ * Check the Resources dictionary ColorSpace entry. pdfi_check_ColorSpace_for_spots is defined
+ * in pdf_colour.c
+ */
+static int pdfi_check_ColorSpace_dict(pdf_context *ctx, pdf_dict *cspace_dict, pdf_dict *page_dict, int *num_spots)
+{
+    int code, i, index;
+    pdf_obj *Key = NULL, *Value = NULL;
+
+    if (pdfi_dict_entries(cspace_dict) > 0) {
+        code = pdfi_loop_detector_mark(ctx); /* Mark the start of the ColorSpace dictionary loop */
+        if (code < 0)
+            return code;
+
+        code = pdfi_dict_first(ctx, cspace_dict, &Key, &Value, (void *)&index);
+        if (code < 0)
+            goto error1;
+
+        i = 1;
+        do {
+            code = pdfi_check_ColorSpace_for_spots(ctx, Value, cspace_dict, page_dict, num_spots);
+            if (code < 0)
+                goto error2;
+
+            pdfi_countdown(Key);
+            Key = NULL;
+            pdfi_countdown(Value);
+            Value = NULL;
+
+            (void)pdfi_loop_detector_cleartomark(ctx); /* Clear to the mark for the Shading dictionary loop */
+
+            code = pdfi_loop_detector_mark(ctx); /* Mark the new start of the Shading dictionary loop */
+            if (code < 0)
+                goto error1;
+
+            do {
+                if (i++ >= pdfi_dict_entries(cspace_dict)) {
+                    code = 0;
+                    goto transparency_exit;
+                }
+
+                code = pdfi_dict_next(ctx, cspace_dict, &Key, &Value, (void *)&index);
+                if (code == 0 && Value->type == PDF_ARRAY)
+                    break;
+                pdfi_countdown(Key);
+                Key = NULL;
+                pdfi_countdown(Value);
+                Value = NULL;
+            } while(1);
+        }while (1);
+    }
+    return 0;
+
+transparency_exit:
+error2:
+    pdfi_countdown(Key);
+    pdfi_countdown(Value);
+
+error1:
+    (void)pdfi_loop_detector_cleartomark(ctx); /* Clear to the mark for the current resource loop */
+    return code;
+}
+
+/*
+ * Process an individual Shading dictionary to see if it contains a ColorSpace with a spot colour
+ */
+static int pdfi_check_Shading(pdf_context *ctx, pdf_dict *shading, pdf_dict *page_dict, int *num_spots)
+{
+    int code;
+    pdf_obj *o = NULL;
+
+    code = pdfi_dict_knownget(ctx, shading, "ColorSpace", (pdf_obj **)&o);
+    if (code > 0) {
+        code = pdfi_check_ColorSpace_for_spots(ctx, o, shading, page_dict, num_spots);
+        pdfi_countdown(o);
+        return code;
+    }
+    return 0;
+}
+
+/*
+ * Check the Resources dictionary Shading entry.
+ */
+static int pdfi_check_Shading_dict(pdf_context *ctx, pdf_dict *shading_dict, pdf_dict *page_dict, int *num_spots)
+{
+    int code, i, index;
+    pdf_obj *Key = NULL, *Value = NULL;
+
+    if (pdfi_dict_entries(shading_dict) > 0) {
+        code = pdfi_loop_detector_mark(ctx); /* Mark the start of the Shading dictionary loop */
+        if (code < 0)
+            return code;
+
+        code = pdfi_dict_first(ctx, shading_dict, &Key, &Value, (void *)&index);
+        if (code < 0 || Value->type != PDF_DICT)
+            goto error1;
+
+        i = 1;
+        do {
+            code = pdfi_check_Shading(ctx, (pdf_dict *)Value, page_dict, num_spots);
+            if (code < 0)
+                goto error2;
+
+            pdfi_countdown(Key);
+            Key = NULL;
+            pdfi_countdown(Value);
+            Value = NULL;
+
+            (void)pdfi_loop_detector_cleartomark(ctx); /* Clear to the mark for the Shading dictionary loop */
+
+            code = pdfi_loop_detector_mark(ctx); /* Mark the new start of the Shading dictionary loop */
+            if (code < 0)
+                goto error1;
+
+            do {
+                if (i++ >= pdfi_dict_entries(shading_dict)) {
+                    code = 0;
+                    goto transparency_exit;
+                }
+
+                code = pdfi_dict_next(ctx, shading_dict, &Key, &Value, (void *)&index);
+                if (code == 0 && Value->type == PDF_DICT)
+                    break;
+                pdfi_countdown(Key);
+                Key = NULL;
+                pdfi_countdown(Value);
+                Value = NULL;
+            } while(1);
+        }while (1);
+    }
+    return 0;
+
+transparency_exit:
+error2:
+    pdfi_countdown(Key);
+    pdfi_countdown(Value);
+
+error1:
+    (void)pdfi_loop_detector_cleartomark(ctx); /* Clear to the mark for the current resource loop */
+    return code;
+}
+
+/*
+ * This routine checks an XObject to see if it contains any spot
+ * colour definitions, or transparency usage.
+ */
+static int pdfi_check_XObject(pdf_context *ctx, pdf_dict *xobject, pdf_dict *page_dict, bool *transparent, int *num_spots)
+{
+    int code = 0;
+    pdf_name *n = NULL;
+    bool known = false;
+    double f;
+
+    code = pdfi_dict_get_type(ctx, xobject, "Subtype", PDF_NAME, (pdf_obj **)&n);
+    if (code >= 0) {
+        if (pdfi_name_is((const pdf_name *)n, "Image")) {
+            pdf_obj *CS = NULL;
+
+            pdfi_countdown(n);
+            n = NULL;
+            code = pdfi_dict_known(xobject, "SMask", &known);
+            if (code >= 0) {
+                if (known == true) {
+                    *transparent = true;
+                    if (num_spots == NULL)
+                        goto transparency_exit;
+                }
+                code = pdfi_dict_knownget_number(ctx, xobject, "SMaskInData", &f);
+                if (code > 0) {
+                    code = 0;
+                    if (f != 0.0)
+                        *transparent = true;
+                    if (num_spots == NULL)
+                        goto transparency_exit;
+                }
+                /* Check the image dictionary for a ColorSpace entry, if we are checking spot names */
+                if (num_spots) {
+                    code = pdfi_dict_knownget(ctx, xobject, "ColorSpace", (pdf_obj **)&CS);
+                    if (code > 0) {
+                        /* We don't care if there's an error here, it'll be picked up if we use the ColorSpace later */
+                        (void)pdfi_check_ColorSpace_for_spots(ctx, CS, xobject, page_dict, num_spots);
+                        pdfi_countdown(CS);
+                    }
+                }
+            }
+        } else {
+            if (pdfi_name_is((const pdf_name *)n, "Form")) {
+                pdf_dict *group_dict = NULL, *resource_dict = NULL;
+                pdf_obj *CS = NULL;
+
+                pdfi_countdown(n);
+                code = pdfi_dict_knownget_type(ctx, xobject, "Group", PDF_DICT, (pdf_obj **)&group_dict);
+                if (code > 0) {
+                    *transparent = true;
+                    if (num_spots == NULL) {
+                        pdfi_countdown(group_dict);
+                        goto transparency_exit;
+                    }
+
+                    /* Start a new loop detector group to avoid this being detected in the Resources check below */
+                    code = pdfi_loop_detector_mark(ctx); /* Mark the start of the XObject dictionary loop */
+                    if (code > 0) {
+                        code = pdfi_dict_knownget(ctx, group_dict, "CS", &CS);
+                        if (code > 0)
+                            /* We don't care if there's an error here, it'll be picked up if we use the ColorSpace later */
+                            (void)pdfi_check_ColorSpace_for_spots(ctx, CS, group_dict, page_dict, num_spots);
+                    }
+                    pdfi_countdown(group_dict);
+                    pdfi_countdown(CS);
+                    (void)pdfi_loop_detector_cleartomark(ctx); /* Clear to the mark for the XObject dictionary loop */
+                }
+
+                code = pdfi_dict_knownget_type(ctx, xobject, "Resources", PDF_DICT, (pdf_obj **)&resource_dict);
+                if (code > 0) {
+                    code = pdfi_check_Resources_for_transparency(ctx, resource_dict, page_dict, transparent, num_spots);
+                    pdfi_countdown(resource_dict);
+                    if (code < 0)
+                        goto transparency_exit;
+                }
+            } else
+                pdfi_countdown(n);
+        }
+    }
+
+    return 0;
+
+transparency_exit:
+    return code;
+}
+
+/*
+ * Check the Resources dictionary XObject entry.
+ */
+static int pdfi_check_XObject_dict(pdf_context *ctx, pdf_dict *xobject_dict, pdf_dict *page_dict, bool *transparent, int *num_spots)
+{
+    int code, i, index;
+    pdf_obj *Key = NULL, *Value = NULL; //, *o = NULL;
+
+    if (pdfi_dict_entries(xobject_dict) > 0) {
+        code = pdfi_loop_detector_mark(ctx); /* Mark the start of the XObject dictionary loop */
+        if (code < 0)
+            return code;
+
+        code = pdfi_dict_first(ctx, xobject_dict, &Key, &Value, (void *)&index);
+        if (code < 0 || Value->type != PDF_DICT)
+            goto error1;
+
+        i = 1;
+        do {
+            code = pdfi_check_XObject(ctx, (pdf_dict *)Value, page_dict, transparent, num_spots);
+            if (code < 0)
+                goto error2;
+
+            (void)pdfi_loop_detector_cleartomark(ctx); /* Clear to the mark for the XObject dictionary loop */
+
+            code = pdfi_loop_detector_mark(ctx); /* Mark the new start of the XObject dictionary loop */
+            if (code < 0)
+                goto error1;
+
+            pdfi_countdown(Key);
+            Key = NULL;
+            pdfi_countdown(Value);
+            Value = NULL;
+
+            do {
+                if (i++ >= pdfi_dict_entries(xobject_dict)) {
+                    code = 0;
+                    goto transparency_exit;
+                }
+
+                code = pdfi_dict_next(ctx, xobject_dict, &Key, &Value, (void *)&index);
+                if (code == 0 && Value->type == PDF_DICT)
+                    break;
+                pdfi_countdown(Key);
+                Key = NULL;
+                pdfi_countdown(Value);
+                Value = NULL;
+            } while(1);
+        }while(1);
+    }
+    return 0;
+
+transparency_exit:
+error2:
+    pdfi_countdown(Key);
+    pdfi_countdown(Value);
+
+error1:
+    (void)pdfi_loop_detector_cleartomark(ctx); /* Clear to the mark for the current resource loop */
+    return code;
+}
+
+/*
+ * This routine checks an ExtGState dictionary to see if it contains any spot
+ * colour definitions, or transparency usage.
+ */
+static int pdfi_check_ExtGState(pdf_context *ctx, pdf_dict *extgstate_dict, pdf_dict *page_dict, bool *transparent, int *num_spots)
+{
+    int code;
+    pdf_obj *o = NULL;
+    double f;
+
+    if (pdfi_dict_entries(extgstate_dict) > 0) {
+        /* Check SMask first, because if we test spot colours first we can exit as
+         * soon as we detect transparency.
+         */
+        code = pdfi_dict_knownget(ctx, extgstate_dict, "SMask", &o);
+        if (code > 0) {
+            if (o->type == PDF_NAME) {
+                if (!pdfi_name_is((pdf_name *)o, "None")) {
+                    pdfi_countdown(o);
+                    *transparent = true;
+                    return 0;
+                }
+            } else {
+                if (o->type == PDF_DICT) {
+                    pdf_obj *G = NULL;
+
+                    *transparent = true;
+
+                    if (num_spots != NULL) {
+                        /* Check if the SMask has a /G (Group) */
+                        code = pdfi_dict_knownget(ctx, (pdf_dict *)o, "G", &G);
+                        if (code > 0) {
+                            code = pdfi_check_XObject(ctx, (pdf_dict *)G, page_dict, transparent, num_spots);
+                            pdfi_countdown(G);
+                        }
+                    }
+                    pdfi_countdown(o);
+                    return code;
+                }
+            }
+        }
+        pdfi_countdown(o);
+        o = NULL;
+
+        code = pdfi_dict_knownget_type(ctx, extgstate_dict, "BM", PDF_NAME, &o);
+        if (code > 0) {
+            if (!pdfi_name_is((pdf_name *)o, "Normal")) {
+                if (!pdfi_name_is((pdf_name *)o, "Compatible")) {
+                    pdfi_countdown(o);
+                    *transparent = true;
+                    return 0;
+                }
+            }
+        }
+        pdfi_countdown(o);
+        o = NULL;
+
+        code = pdfi_dict_knownget_number(ctx, extgstate_dict, "CA", &f);
+        if (code > 0) {
+            if (f != 1.0) {
+                *transparent = true;
+                return 0;
+            }
+        }
+
+        code = pdfi_dict_knownget_number(ctx, extgstate_dict, "ca", &f);
+        if (code > 0) {
+            if (f != 1.0) {
+                *transparent = true;
+                return 0;
+            }
+        }
+    }
+    return 0;
+}
+
+/*
+ * Check the Resources dictionary ExtGState entry.
+ */
+static int pdfi_check_ExtGState_dict(pdf_context *ctx, pdf_dict *extgstate_dict, pdf_dict *page_dict, bool *transparent, int *num_spots)
+{
+    int code, i, index;
+    pdf_obj *Key = NULL, *Value = NULL;
+
+    if (pdfi_dict_entries(extgstate_dict) > 0) {
+        code = pdfi_loop_detector_mark(ctx); /* Mark the start of the ColorSpace dictionary loop */
+        if (code < 0)
+            return code;
+
+        code = pdfi_dict_first(ctx, extgstate_dict, &Key, &Value, (void *)&index);
+        if (code < 0)
+            goto error1;
+
+        i = 1;
+        do {
+
+            (void)pdfi_check_ExtGState(ctx, (pdf_dict *)Value, page_dict, transparent, num_spots);
+            if (*transparent == true && num_spots == NULL)
+                goto transparency_exit;
+
+            pdfi_countdown(Key);
+            Key = NULL;
+            pdfi_countdown(Value);
+            Value = NULL;
+
+            (void)pdfi_loop_detector_cleartomark(ctx); /* Clear to the mark for the ExtGState dictionary loop */
+
+            code = pdfi_loop_detector_mark(ctx); /* Mark the new start of the ExtGState dictionary loop */
+            if (code < 0)
+                goto error1;
+
+            do {
+                if (i++ >= pdfi_dict_entries(extgstate_dict)) {
+                    code = 0;
+                    goto transparency_exit;
+                }
+
+                code = pdfi_dict_next(ctx, extgstate_dict, &Key, &Value, (void *)&index);
+                if (code == 0 && Value->type == PDF_DICT)
+                    break;
+                pdfi_countdown(Key);
+                Key = NULL;
+                pdfi_countdown(Value);
+                Value = NULL;
+            } while(1);
+        }while (1);
+    }
+    return 0;
+
+transparency_exit:
+    pdfi_countdown(Key);
+    pdfi_countdown(Value);
+
+error1:
+    (void)pdfi_loop_detector_cleartomark(ctx); /* Clear to the mark for the current resource loop */
+    return code;
+}
+
+/*
+ * This routine checks a Pattern dictionary to see if it contains any spot
+ * colour definitions, or transparency usage.
+ */
+int pdfi_check_Pattern(pdf_context *ctx, pdf_dict *pattern, pdf_dict *page_dict, bool *transparent, int *num_spots)
+{
+    int code = 0;
+    pdf_obj *o = NULL;
+
+    if (num_spots != NULL) {
+        code = pdfi_dict_knownget_type(ctx, pattern, "Shading", PDF_DICT, &o);
+        if (code > 0)
+            (void)pdfi_check_Shading(ctx, (pdf_dict *)o, page_dict, num_spots);
+        pdfi_countdown(o);
+        o = NULL;
+    }
+
+    code = pdfi_dict_knownget_type(ctx, pattern, "Resources", PDF_DICT, &o);
+    if (code > 0)
+        (void)pdfi_check_Resources_for_transparency(ctx, (pdf_dict *)o, page_dict, transparent, num_spots);
+    pdfi_countdown(o);
+    o = NULL;
+    if (*transparent == true && num_spots == NULL)
+        goto transparency_exit;
+
+    code = pdfi_dict_knownget_type(ctx, pattern, "ExtGState", PDF_DICT, &o);
+    if (code > 0)
+        (void)pdfi_check_ExtGState(ctx, (pdf_dict *)o, page_dict, transparent, num_spots);
+    pdfi_countdown(o);
+    o = NULL;
+
+transparency_exit:
+    return 0;
+}
+
+/*
+ * Check the Resources dictionary Pattern entry.
+ */
+static int pdfi_check_Pattern_dict(pdf_context *ctx, pdf_dict *pattern_dict, pdf_dict *page_dict, bool *transparent, int *num_spots)
+{
+    int code, i, index;
+    pdf_obj *Key = NULL, *Value = NULL;
+
+    if (pdfi_dict_entries(pattern_dict) > 0) {
+        code = pdfi_loop_detector_mark(ctx); /* Mark the start of the Pattern dictionary loop */
+        if (code < 0)
+            return code;
+
+        code = pdfi_dict_first(ctx, pattern_dict, &Key, &Value, (void *)&index);
+        if (code < 0)
+            goto error1;
+
+        if (Value->type != PDF_DICT)
+            goto transparency_exit;
+
+        i = 1;
+        do {
+            code = pdfi_check_Pattern(ctx, (pdf_dict *)Value, page_dict, transparent, num_spots);
+            if (code < 0)
+                goto transparency_exit;
+
+            pdfi_countdown(Key);
+            Key = NULL;
+            pdfi_countdown(Value);
+            Value = NULL;
+            (void)pdfi_loop_detector_cleartomark(ctx); /* Clear to the mark for the Shading dictionary loop */
+
+            code = pdfi_loop_detector_mark(ctx); /* Mark the new start of the Shading dictionary loop */
+            if (code < 0)
+                goto error1;
+
+            do {
+                if (i++ >= pdfi_dict_entries(pattern_dict)) {
+                    code = 0;
+                    goto transparency_exit;
+                }
+
+                code = pdfi_dict_next(ctx, pattern_dict, &Key, &Value, (void *)&index);
+                if (code == 0 && Value->type == PDF_DICT)
+                    break;
+                pdfi_countdown(Key);
+                Key = NULL;
+                pdfi_countdown(Value);
+                Value = NULL;
+            } while(1);
+        }while (1);
+    }
+    return 0;
+
+transparency_exit:
+    pdfi_countdown(Key);
+    pdfi_countdown(Value);
+
+error1:
+    (void)pdfi_loop_detector_cleartomark(ctx); /* Clear to the mark for the current resource loop */
+    return code;
+}
+
+/*
+ * This routine checks a Font dictionary to see if it contains any spot
+ * colour definitions, or transparency usage.
+ */
+static int pdfi_check_Font(pdf_context *ctx, pdf_dict *font, pdf_dict *page_dict, bool *transparent, int *num_spots)
+{
+    int code = 0;
+    pdf_obj *o = NULL;
+
+    code = pdfi_dict_knownget_type(ctx, font, "Subtype", PDF_NAME, &o);
+    if (code > 0) {
+        if (pdfi_name_is((pdf_name *)o, "Type3")) {
+            pdfi_countdown(o);
+            o = NULL;
+
+            code = pdfi_dict_knownget_type(ctx, font, "Resources", PDF_DICT, &o);
+            if (code > 0)
+                (void)pdfi_check_Resources_for_transparency(ctx, (pdf_dict *)o, page_dict, transparent, num_spots);
+        }
+    }
+    pdfi_countdown(o);
+    o = NULL;
+
+    return 0;
+}
+
+/*
+ * Check the Resources dictionary Font entry.
+ */
+static int pdfi_check_Font_dict(pdf_context *ctx, pdf_dict *font_dict, pdf_dict *page_dict, bool *transparent, int *num_spots)
+{
+    int code, i, index;
+    pdf_obj *Key = NULL, *Value = NULL;
+
+    if (pdfi_dict_entries(font_dict) > 0) {
+        code = pdfi_loop_detector_mark(ctx); /* Mark the start of the Font dictionary loop */
+        if (code < 0)
+            return code;
+
+        code = pdfi_dict_first(ctx, font_dict, &Key, &Value, (void *)&index);
+        if (code < 0)
+            goto error1;
+
+        i = 1;
+        do {
+            code = pdfi_check_Font(ctx, (pdf_dict *)Value, page_dict, transparent, num_spots);
+
+            pdfi_countdown(Key);
+            Key = NULL;
+            pdfi_countdown(Value);
+            Value = NULL;
+
+            (void)pdfi_loop_detector_cleartomark(ctx); /* Clear to the mark for the Font dictionary loop */
+
+            code = pdfi_loop_detector_mark(ctx); /* Mark the new start of the Font dictionary loop */
+            if (code < 0)
+                goto error1;
+
+            do {
+                if (i++ >= pdfi_dict_entries(font_dict)) {
+                    code = 0;
+                    goto transparency_exit;
+                }
+
+                code = pdfi_dict_next(ctx, font_dict, &Key, &Value, (void *)&index);
+                if (code == 0 && Value->type == PDF_DICT)
+                    break;
+                pdfi_countdown(Key);
+                Key = NULL;
+                pdfi_countdown(Value);
+                Value = NULL;
+            } while(1);
+        }while (1);
+    }
+    return 0;
+
+transparency_exit:
+    pdfi_countdown(Key);
+    pdfi_countdown(Value);
+
+error1:
+    (void)pdfi_loop_detector_cleartomark(ctx); /* Clear to the mark for the current resource loop */
+    return code;
+}
+
+static int pdfi_check_Resources_for_transparency(pdf_context *ctx, pdf_dict *Resources_dict, pdf_dict *page_dict, bool *transparent, int *num_spots)
+{
+    int code;
+    pdf_obj *d = NULL;
+
+    /* First up, check any colour spaces, for new spot colours.
+     * We only do this if asked because its expensive. num_spots being NULL
+     * means we aren't interested in spot colours (not a DeviceN or Separation device)
+     */
+    if (num_spots != NULL) {
+        code = pdfi_dict_knownget_type(ctx, Resources_dict, "ColorSpace", PDF_DICT, &d);
+        if (code > 0)
+            (void)pdfi_check_ColorSpace_dict(ctx, (pdf_dict *)d, page_dict, num_spots);
+
+        pdfi_countdown(d);
+        d = NULL;
+
+        code = pdfi_dict_knownget_type(ctx, Resources_dict, "Shading", PDF_DICT, &d);
+        if (code > 0)
+            (void)pdfi_check_Shading_dict(ctx, (pdf_dict *)d, page_dict, num_spots);
+        pdfi_countdown(d);
+        d = NULL;
+    }
+
+    code = pdfi_dict_knownget_type(ctx, Resources_dict, "XObject", PDF_DICT, &d);
+    if (code > 0)
+        (void)pdfi_check_XObject_dict(ctx, (pdf_dict *)d, page_dict, transparent, num_spots);
+    pdfi_countdown(d);
+    d = NULL;
+
+    code = pdfi_dict_knownget_type(ctx, Resources_dict, "Pattern", PDF_DICT, &d);
+    if (code > 0)
+        (void)pdfi_check_Pattern_dict(ctx, (pdf_dict *)d, page_dict, transparent, num_spots);
+    pdfi_countdown(d);
+    d = NULL;
+
+    code = pdfi_dict_knownget_type(ctx, Resources_dict, "Font", PDF_DICT, &d);
+    if (code > 0)
+        (void)pdfi_check_Font_dict(ctx, (pdf_dict *)d, page_dict, transparent, num_spots);
+    /* From this point onwards, if we detect transparency (or have already detected it) we
+     * can exit, we have already counted up any spot colours.
+     */
+    pdfi_countdown(d);
+    d = NULL;
+
+    code = pdfi_dict_knownget_type(ctx, Resources_dict, "ExtGState", PDF_DICT, &d);
+    if (code > 0)
+        (void)pdfi_check_ExtGState_dict(ctx, (pdf_dict *)d, page_dict, transparent, num_spots);
+    pdfi_countdown(d);
+    d = NULL;
+
+    return 0;
+}
+
+static int pdfi_check_annot_for_transparency(pdf_context *ctx, pdf_dict *annot, pdf_dict *page_dict, bool *transparent, int *num_spots)
+{
+    int code;
+    pdf_name *n;
+    pdf_dict *ap = NULL, *N = NULL, *Resources = NULL;
+    double f;
+
+    /* Check #1 Does the (Normal) Appearnce stream use any Resources which include transparency.
+     * We check this first, because this also checks for spot colour spaces. Once we've done that we
+     * can exit the checks as soon as we detect transparency.
+     */
+    code = pdfi_dict_knownget_type(ctx, annot, "AP", PDF_DICT, (pdf_obj **)&ap);
+    if (code > 0)
+    {
+        code = pdfi_dict_knownget_type(ctx, ap, "N", PDF_DICT, (pdf_obj **)&N);
+        if (code > 0) {
+            code = pdfi_dict_knownget_type(ctx, N, "Resources", PDF_DICT, (pdf_obj **)&Resources);
+            if (code > 0)
+                code = pdfi_check_Resources_for_transparency(ctx, (pdf_dict *)Resources, page_dict, transparent, num_spots);
+        }
+    }
+    pdfi_countdown(ap);
+    pdfi_countdown(N);
+    pdfi_countdown(Resources);
+    if (code < 0)
+        return code;
+    /* We've checked the Resources, and nothing else in an annotation can define spot colours, so
+     * if we detected transparency in the Resources we need not check further.
+     */
+    if (*transparent == true)
+        return 0;
+
+    code = pdfi_dict_get_type(ctx, annot, "Subtype", PDF_NAME, (pdf_obj **)&n);
+    if (code < 0) {
+        if (ctx->pdfstoponerror)
+            return code;
+    } else {
+        /* Check #2, Highlight annotations are always preformed with transparency */
+        if (pdfi_name_is((const pdf_name *)n, "Highlight")) {
+            pdfi_countdown(n);
+            *transparent = true;
+            return 0;
+        }
+        pdfi_countdown(n);
+        n = NULL;
+
+        /* Check #3 Blend Mode (BM) not being 'Normal' or 'Compatible' */
+        code = pdfi_dict_knownget_type(ctx, annot, "BM", PDF_NAME, (pdf_obj **)&n);
+        if (code > 0) {
+            if (!pdfi_name_is((const pdf_name *)n, "Normal")) {
+                if (!pdfi_name_is((const pdf_name *)n, "Compatible")) {
+                    pdfi_countdown(n);
+                    *transparent = true;
+                    return 0;
+                }
+            }
+            code = 0;
+        }
+        pdfi_countdown(n);
+        if (code < 0)
+            return code;
+
+        /* Check #4 stroke constant alpha (CA) is not 1 (100% opaque) */
+        code = pdfi_dict_knownget_number(ctx, annot, "CA", &f);
+        if (code > 0) {
+            if (f != 1.0) {
+                *transparent = true;
+                return 0;
+            }
+        }
+        if (code < 0)
+            return code;
+
+        /* Check #5 non-stroke constant alpha (ca) is not 1 (100% opaque) */
+        code = pdfi_dict_knownget_number(ctx, annot, "ca", &f);
+        if (code > 0) {
+            if (f != 1.0) {
+                *transparent = true;
+                return 0;
+            }
+        }
+        if (code < 0)
+            return code;
+    }
+
+    return 0;
+}
+
+static int pdfi_check_Annots_for_transparency(pdf_context *ctx, pdf_array *annots_array, pdf_dict *page_dict, bool *transparent, int *num_spots)
+{
+    int i, code = 0;
+    pdf_dict *annot = NULL;
+
+    for (i=0; i < pdfi_array_size(annots_array); i++) {
+        code = pdfi_array_get_type(ctx, annots_array, (uint64_t)i, PDF_DICT, (pdf_obj **)&annot);
+        if (code > 0) {
+            code = pdfi_check_annot_for_transparency(ctx, annot, page_dict, transparent, num_spots);
+            if (code < 0 && ctx->pdfstoponerror)
+                goto exit;
+
+            /* If we've found transparency, and don't need to continue checkign for spot colours
+             * just exit as fast as possible.
+             */
+            if (*transparent == true && num_spots == NULL)
+                goto exit;
+
+            pdfi_countdown(annot);
+            annot = NULL;
+        }
+    }
+exit:
+    pdfi_countdown(annot);
+    return code;
+}
+
+int pdfi_check_transparency_spots(pdf_context *ctx)
+{
+    int code = 0;
+
+    /* Loop round all the pages looking for spot colours and transparency. We only check
+     * for spot colours if the device is capable of spot colours (the code checks). We
+     * only store the transparency setting if NOTRANSPARENCY is not set
+     */
+    if (ctx->num_pages) {
+        pdf_dict *page_dict = NULL;
+        uint64_t page_offset = 0;
+        bool uses_transparency = false;
+        int spots = 0;
+        uint64_t ix;
+
+        int bytes = (int)ceil((float)ctx->num_pages / 8.0f);
+        ctx->PageTransparencyArray = (char *)gs_alloc_bytes(ctx->memory, bytes, "pdfi_process_file, allocate page transparency tracking array");
+        memset(ctx->PageTransparencyArray, 0x00, bytes);
+
+        code = pdfi_alloc_object(ctx, PDF_DICT, 32, (pdf_obj **)&ctx->SpotNames);
+        if (code < 0)
+            goto exit;
+
+        pdfi_countup(ctx->SpotNames);
+
+        for (ix=0;ix < ctx->num_pages;ix++) {
+            if (ctx->pdfdebug)
+                dmprintf1(ctx->memory, "%% Checking Page %"PRIi64" for transparency and spot plates\n", ix + 1);
+
+            uses_transparency = false;
+
+            /* Get the page dictionary */
+            code = pdfi_loop_detector_mark(ctx);
+            if (code < 0)
+                goto exit;
+
+            code = pdfi_loop_detector_add_object(ctx, ctx->Pages->object_num);
+            if (code < 0) {
+                pdfi_loop_detector_cleartomark(ctx);
+                goto exit;
+            }
+
+            page_offset = 0;
+            code = pdfi_get_page_dict(ctx, ctx->Pages, ix, &page_offset, &page_dict, NULL);
+            pdfi_loop_detector_cleartomark(ctx);
+            if (code < 0) {
+                if (code == gs_error_VMerror || ctx->pdfstoponerror)
+                    goto exit;
+                return 0;
+            }
+
+            if (code > 0) {
+                /* This can happen if the number of declared pages (/Count) is larger than the number of pages in the Pages array
+                 * We'll ignore that for the purposes of transparency checking. If the user tries to render this
+                 * page it'll fail in the page rendering code.
+                 */
+                pdfi_countdown(page_dict);
+                page_dict = NULL;
+                break;
+            }
+
+            /* Check the page dictionary for spots and transparency */
+            code = pdfi_check_page_transparency(ctx, page_dict, &uses_transparency, &spots);
+            if (code < 0) {
+                pdfi_countdown(ctx->SpotNames);
+                pdfi_countdown(page_dict);
+                ctx->SpotNames = NULL;
+                goto exit;
+            }
+            if (uses_transparency && !ctx->notransparency) {
+                uint64_t index = ix >> 3;
+                char value = 0x80 >> (ix % 8);
+
+                ctx->PageTransparencyArray[index] |= value;
+            }
+            pdfi_countdown(page_dict);
+            page_dict = NULL;
+        }
+
+        pdfi_countdown(ctx->SpotNames);
+        ctx->SpotNames = NULL;
+
+        /* If there are spot colours (and by inference, the device renders spot plates) then
+         * send the number of Spots to the device, so it can setup correctly.
+         */
+        if (spots > 0) {
+            gs_c_param_list_write(&ctx->pdfi_param_list, ctx->memory);
+            param_write_int((gs_param_list *)&ctx->pdfi_param_list, "PageSpotColors", &spots);
+            gs_c_param_list_read(&ctx->pdfi_param_list);
+            code = gs_putdeviceparams(ctx->pgs->device, (gs_param_list *)&ctx->pdfi_param_list);
+            if (code > 0) {
+                /* The device was closed, we need to reopen it */
+                code = gs_setdevice_no_erase(ctx->pgs, ctx->pgs->device);
+                if (code < 0) {
+                    if (uses_transparency)
+                        (void)gs_abort_pdf14trans_device(ctx->pgs);
+                    pdfi_countdown(ctx->SpotNames);
+                    pdfi_countdown(page_dict);
+                    goto exit;
+                }
+                gs_erasepage(ctx->pgs);
+            }
+        }
+    }
+exit:
+    return code;
+}
+
+/* From the original PDF interpreter written in PostScript:
+ * Note: we deliberately don't check to see whether a Group is defined,
+ * because Adobe Illustrator 10 (and possibly other applications) define
+ * a page-level group whether transparency is actually used or not.
+ * Ignoring the presence of Group is justified because, in the absence
+ * of any other transparency features, they have no effect.
+ */
+int pdfi_check_page_transparency(pdf_context *ctx, pdf_dict *page_dict, bool *transparent, int *spots)
+{
+    int code;
+    pdf_obj *d = NULL;
+    int num_spots = 0;
+    pdf_dict *group_dict = NULL;
+
+    /* Note that we don't reset 'spots' to 0 because these accumulate across pages */
+    *transparent = false;
+
+    ctx->spot_capable_device = false;
+    gs_c_param_list_read(&ctx->pdfi_param_list);
+    code = param_read_int((gs_param_list *)&ctx->pdfi_param_list, "PageSpotColors", &ctx->spot_capable_device);
+    if (code < 0)
+        return code;
+    if (code > 0)
+        ctx->spot_capable_device = 0;
+    else
+        ctx->spot_capable_device = 1;
+
+    /* Check if the page dictionary has a page Group entry */
+    code = pdfi_dict_knownget_type(ctx, page_dict, "Group", PDF_DICT, (pdf_obj **)&group_dict);
+    if (code > 0) {
+        pdf_obj *CS = NULL;
+
+        /* Page group means the page is transparent but we ignore it for the purposes
+         * of transparency detection. See above.
+         */
+        if (ctx->spot_capable_device) {
+            /* Check the Group to see if it has a ColorSpace (CS) and if it
+             * does whether it has any spot colours */
+            code = pdfi_dict_knownget(ctx, group_dict, "CS", &CS);
+            if (code > 0) {
+                code = pdfi_check_ColorSpace_for_spots(ctx, CS, group_dict, page_dict, spots);
+                if (code < 0 && ctx->pdfstoponerror) {
+                    pdfi_countdown(CS);
+                    pdfi_countdown(group_dict);
+                    pdfi_countdown(ctx->SpotNames);
+                    return code;
+                }
+                pdfi_countdown(CS);
+            }
+        }
+        pdfi_countdown(group_dict);
+    }
+
+    /* Now check any Resources dictionary in the Page dictionary */
+    code = pdfi_dict_get_type(ctx, page_dict, "Resources", PDF_DICT, &d);
+    if (code >= 0) {
+        if (ctx->spot_capable_device)
+            code = pdfi_check_Resources_for_transparency(ctx, (pdf_dict *)d, page_dict, transparent, &num_spots);
+        else
+            code = pdfi_check_Resources_for_transparency(ctx, (pdf_dict *)d, page_dict, transparent, NULL);
+        pdfi_countdown(d);
+        if (code < 0)
+            return code;
+    }
+    if (code < 0 && code != gs_error_undefined && ctx->pdfstoponerror)
+        return code;
+
+    /* If we are drawing Annotations, check to see if the page uses any Annots */
+    if (ctx->showannots) {
+        code = pdfi_dict_get_type(ctx, page_dict, "Annots", PDF_ARRAY, &d);
+        if (code >= 0) {
+            if (ctx->spot_capable_device)
+                code = pdfi_check_Annots_for_transparency(ctx, (pdf_array *)d, page_dict, transparent, &num_spots);
+            else
+                code = pdfi_check_Annots_for_transparency(ctx, (pdf_array *)d, page_dict, transparent, NULL);
+            pdfi_countdown(d);
+            if (code < 0)
+                return code;
+        }
+        if (code < 0 && code != gs_error_undefined && ctx->pdfstoponerror)
+            return code;
+    }
+
+    if (ctx->spot_capable_device)
+        *spots += num_spots;
+    else
+        *spots = 0;
+
+    return 0;
+}
diff --git a/pdf/pdf_page.h b/pdf/pdf_check.h
similarity index 59%
copy from pdf/pdf_page.h
copy to pdf/pdf_check.h
index c1213e3..7d67447 100644
--- a/pdf/pdf_page.h
+++ b/pdf/pdf_check.h
@@ -1,4 +1,4 @@
-/* Copyright (C) 2001-2018 Artifex Software, Inc.
+/* Copyright (C) 2001-2019 Artifex Software, Inc.
    All Rights Reserved.
 
    This software is provided AS-IS with no warranty, either express or
@@ -13,11 +13,12 @@
    CA 94945, U.S.A., +1(415)492-9861, for further information.
 */
 
-/* Page-level operations for the PDF interpreter */
+#ifndef PDF_CHECK
+#define PDF_CHECK
 
-#ifndef PDF_PAGE_OPERATORS
-#define PDF_PAGE_OPERATORS
+int pdfi_check_transparency_spots(pdf_context *ctx);
+int pdfi_check_page_transparency(pdf_context *ctx, pdf_dict *page_dict, bool *transparent, int *spots);
 
-/* NOTE: used to have OC stuff here, moved to pdf_optcontent.h */
+int pdfi_check_Pattern(pdf_context *ctx, pdf_dict *pattern, pdf_dict *page_dict, bool *transparent, int *num_spots);
 
 #endif
diff --git a/pdf/pdf_page.c b/pdf/pdf_page.c
index b8aef1a..d0216f8 100644
--- a/pdf/pdf_page.c
+++ b/pdf/pdf_page.c
@@ -1,4 +1,4 @@
-/* Copyright (C) 2001-2018 Artifex Software, Inc.
+/* Copyright (C) 2001-2019 Artifex Software, Inc.
    All Rights Reserved.
 
    This software is provided AS-IS with no warranty, either express or
@@ -16,6 +16,7 @@
 /* Page-level operations for the PDF interpreter */
 
 #include "pdf_int.h"
+#include "plmain.h"
 #include "pdf_stack.h"
 #include "pdf_page.h"
 #include "pdf_file.h"
@@ -24,13 +25,419 @@
 #include "pdf_loop_detect.h"
 #include "pdf_colour.h"
 #include "pdf_trans.h"
+#include "pdf_gstate.h"
 #include "pdf_misc.h"
+#include "pdf_optcontent.h"
 
-#include "gsiparm4.h"
-#include "gsiparm3.h"
+static int pdfi_process_page_contents(pdf_context *ctx, pdf_dict *page_dict)
+{
+    int i, code = 0;
+    pdf_obj *o, *o1;
 
-#include "gstrans.h"
+    code = pdfi_dict_get(ctx, page_dict, "Contents", &o);
+    if (code == gs_error_undefined)
+        /* Don't throw an error if there are no contents, just render nothing.... */
+        return 0;
+    if (code < 0)
+        return code;
 
-/* NOTE: I used to have the OC stuff here, moved it to pdf_optcontent.c
- * Maybe this file will have other things at some point, else it could be deleted.
- */
+    if (o->type == PDF_INDIRECT) {
+        if (((pdf_indirect_ref *)o)->ref_object_num == page_dict->object_num)
+            return_error(gs_error_circular_reference);
+
+        code = pdfi_dereference(ctx, ((pdf_indirect_ref *)o)->ref_object_num, ((pdf_indirect_ref *)o)->ref_generation_num, &o1);
+        pdfi_countdown(o);
+        if (code < 0) {
+            if (code == gs_error_VMerror)
+                return code;
+            return 0;
+        }
+        o = o1;
+    }
+
+    code = pdfi_gsave(ctx);
+    if (code < 0) {
+        pdfi_countdown(o);
+        return code;
+    }
+
+    if (o->type == PDF_ARRAY) {
+        pdf_array *a = (pdf_array *)o;
+
+        for (i=0;i < pdfi_array_size(a); i++) {
+            pdf_indirect_ref *r;
+            code = pdfi_array_get_no_deref(ctx, a, i, (pdf_obj **)&r);
+            if (code < 0)
+                goto page_error;
+            if (r->type == PDF_DICT) {
+                code = pdfi_interpret_content_stream(ctx, (pdf_dict *)r, page_dict);
+                pdfi_countdown(r);
+                if (code < 0)
+                    goto page_error;
+            } else {
+                if (r->type != PDF_INDIRECT) {
+                        pdfi_countdown(r);
+                        code = gs_note_error(gs_error_typecheck);
+                        goto page_error;
+                } else {
+                    if (r->ref_object_num == page_dict->object_num) {
+                        pdfi_countdown(r);
+                        code = gs_note_error(gs_error_circular_reference);
+                        goto page_error;
+                    }
+                    code = pdfi_dereference(ctx, r->ref_object_num, r->ref_generation_num, &o1);
+                    pdfi_countdown(r);
+                    if (code < 0) {
+                        if (code != gs_error_VMerror || ctx->pdfstoponerror == false)
+                            code = 0;
+                        goto page_error;
+                    }
+                    if (o1->type != PDF_DICT) {
+                        pdfi_countdown(o1);
+                        code = gs_note_error(gs_error_typecheck);
+                        goto page_error;
+                    }
+                    code = pdfi_interpret_content_stream(ctx, (pdf_dict *)o1, page_dict);
+                    pdfi_countdown(o1);
+                    if (code < 0) {
+                        if (code == gs_error_VMerror || ctx->pdfstoponerror == true)
+                            goto page_error;
+                    }
+                }
+            }
+        }
+    } else {
+        if (o->type == PDF_DICT) {
+            code = pdfi_interpret_content_stream(ctx, (pdf_dict *)o, page_dict);
+        } else {
+            pdfi_countdown(o);
+            return_error(gs_error_typecheck);
+        }
+    }
+page_error:
+    pdfi_grestore(ctx);
+    pdfi_countdown(o);
+    return code;
+}
+
+static int pdfi_set_media_size(pdf_context *ctx, pdf_dict *page_dict)
+{
+    gs_c_param_list list;
+    gs_param_float_array fa;
+    pdf_array *a = NULL, *default_media = NULL;
+    float fv[2];
+    double d[4];
+    int code;
+    uint64_t i;
+    int64_t rotate = 0;
+
+    gs_c_param_list_write(&list, ctx->memory);
+
+    code = pdfi_dict_get_type(ctx, page_dict, "MediaBox", PDF_ARRAY, (pdf_obj **)&default_media);
+    if (code < 0) {
+        code = gs_erasepage(ctx->pgs);
+        return 0;
+    }
+
+    if (ctx->usecropbox) {
+        if (a != NULL)
+            pdfi_countdown(a);
+        (void)pdfi_dict_get_type(ctx, page_dict, "CropBox", PDF_ARRAY, (pdf_obj **)&a);
+    }
+    if (ctx->useartbox) {
+        if (a != NULL)
+            pdfi_countdown(a);
+        (void)pdfi_dict_get_type(ctx, page_dict, "ArtBox", PDF_ARRAY, (pdf_obj **)&a);
+    }
+    if (ctx->usebleedbox) {
+        if (a != NULL)
+            pdfi_countdown(a);
+        (void)pdfi_dict_get_type(ctx, page_dict, "BleedBox", PDF_ARRAY, (pdf_obj **)&a);
+    }
+    if (ctx->usetrimbox) {
+        if (a != NULL)
+            pdfi_countdown(a);
+        (void)pdfi_dict_get_type(ctx, page_dict, "MediaBox", PDF_ARRAY, (pdf_obj **)&a);
+    }
+    if (a == NULL)
+        a = default_media;
+
+    for (i=0;i<4;i++) {
+        code = pdfi_array_get_number(ctx, a, i, &d[i]);
+    }
+    pdfi_countdown(a);
+
+    normalize_rectangle(d);
+    memcpy(ctx->PageSize, d, 4 * sizeof(double));
+
+    code = pdfi_dict_get_int(ctx, page_dict, "Rotate", &rotate);
+
+    rotate = rotate % 360;
+
+    switch(rotate) {
+        default:
+        case 0:
+        case 360:
+        case -180:
+        case 180:
+            fv[0] = (float)(d[2] - d[0]);
+            fv[1] = (float)(d[3] - d[1]);
+            break;
+        case -90:
+        case 90:
+        case -270:
+        case 270:
+            fv[1] = (float)(d[2] - d[0]);
+            fv[0] = (float)(d[3] - d[1]);
+            break;
+    }
+
+    fa.persistent = false;
+    fa.data = fv;
+    fa.size = 2;
+
+    code = param_write_float_array((gs_param_list *)&list, ".MediaSize", &fa);
+    if (code >= 0)
+    {
+        gx_device *dev = gs_currentdevice(ctx->pgs);
+
+        gs_c_param_list_read(&list);
+        code = gs_putdeviceparams(dev, (gs_param_list *)&list);
+        if (code < 0) {
+            gs_c_param_list_release(&list);
+            return code;
+        }
+    }
+    gs_c_param_list_release(&list);
+
+    gs_initgraphics(ctx->pgs);
+
+    switch(rotate) {
+        case 0:
+            break;
+        case -270:
+        case 90:
+            gs_translate(ctx->pgs, 0, fv[1]);
+            gs_rotate(ctx->pgs, -90);
+            break;
+        case -180:
+        case 180:
+            gs_translate(ctx->pgs, fv[0], fv[1]);
+            gs_rotate(ctx->pgs, 180);
+            break;
+        case -90:
+        case 270:
+            gs_translate(ctx->pgs, fv[0], 0);
+            gs_rotate(ctx->pgs, 90);
+            break;
+        default:
+            break;
+    }
+
+    gs_translate(ctx->pgs, d[0] * -1, d[1] * -1);
+
+    code = gs_erasepage(ctx->pgs);
+    return 0;
+}
+
+int pdfi_page_render(pdf_context *ctx, uint64_t page_num)
+{
+    int code, code1=0;
+    uint64_t page_offset = 0;
+    pdf_dict *page_dict = NULL;
+    bool uses_transparency = false;
+    bool page_group_known = false;
+    int page_index = page_num >> 3;
+    char page_bit = 0x80 >> (page_num % 8);
+    stream_save local_entry_save;
+    pdf_dict *group_dict = NULL;
+
+    if (page_num > ctx->num_pages)
+        return_error(gs_error_rangecheck);
+
+    if (ctx->pdfdebug)
+        dmprintf1(ctx->memory, "%% Processing Page %"PRIi64" content stream\n", page_num + 1);
+
+    code = pdfi_loop_detector_mark(ctx);
+    if (code < 0)
+        return code;
+
+    code = pdfi_loop_detector_add_object(ctx, ctx->Pages->object_num);
+    if (code < 0) {
+        pdfi_loop_detector_cleartomark(ctx);
+        goto exit2;
+    }
+
+    code = pdfi_get_page_dict(ctx, ctx->Pages, page_num, &page_offset, &page_dict, NULL);
+    pdfi_loop_detector_cleartomark(ctx);
+    if (code < 0) {
+        if (code == gs_error_VMerror || ctx->pdfstoponerror)
+            goto exit2;
+        code = 0;
+        goto exit2;
+    }
+
+    if (code > 0) {
+        code = gs_note_error(gs_error_unknownerror);
+        goto exit2;
+    }
+
+    code = pdfi_set_media_size(ctx, page_dict);
+    if (code < 0) {
+        goto exit2;
+    }
+
+    code = pdfi_dict_knownget_type(ctx, page_dict, "Group", PDF_DICT, (pdf_obj **)&group_dict);
+    if (code < 0)
+        goto exit2;
+    if (group_dict != NULL)
+        page_group_known = true;
+
+    pdfi_countdown(ctx->CurrentPageDict);
+    ctx->CurrentPageDict = page_dict;
+    pdfi_countup(ctx->CurrentPageDict);
+
+    code = gs_setstrokeconstantalpha(ctx->pgs, 1.0);
+    code = gs_setfillconstantalpha(ctx->pgs, 1.0);
+    code = gs_setalphaisshape(ctx->pgs, 0);
+    code = gs_setblendmode(ctx->pgs, BLEND_MODE_Compatible);
+    code = gs_settextknockout(ctx->pgs, true);
+    code = gs_settextspacing(ctx->pgs, (double)0.0);
+    code = gs_settextleading(ctx->pgs, (double)0.0);
+    gs_settextrenderingmode(ctx->pgs, 0);
+    code = gs_setwordspacing(ctx->pgs, (double)0.0);
+    code = gs_settexthscaling(ctx->pgs, (double)100.0);
+    ctx->TextBlockDepth = 0;
+
+    if (ctx->pgs->set_transfer.red == 0x00) {
+        ctx->DefaultTransfers[0].proc = gs_identity_transfer;
+        memset(ctx->DefaultTransfers[0].values, 0x00, transfer_map_size * sizeof(frac));
+    } else {
+        ctx->DefaultTransfers[0].proc = ctx->pgs->set_transfer.red->proc;
+        memcpy(ctx->DefaultTransfers[0].values, ctx->pgs->set_transfer.red->values, transfer_map_size * sizeof(frac));
+    }
+    if (ctx->pgs->set_transfer.green == 0x00) {
+        ctx->DefaultTransfers[1].proc = gs_identity_transfer;
+        memset(ctx->DefaultTransfers[1].values, 0x00, transfer_map_size * sizeof(frac));
+    } else {
+        ctx->DefaultTransfers[1].proc = ctx->pgs->set_transfer.green->proc;
+        memcpy(ctx->DefaultTransfers[1].values, ctx->pgs->set_transfer.green->values, transfer_map_size * sizeof(frac));
+    }
+    if (ctx->pgs->set_transfer.blue == 0x00) {
+        ctx->DefaultTransfers[2].proc = gs_identity_transfer;
+        memset(ctx->DefaultTransfers[2].values, 0x00, transfer_map_size * sizeof(frac));
+    } else {
+        ctx->DefaultTransfers[2].proc = ctx->pgs->set_transfer.blue->proc;
+        memcpy(ctx->DefaultTransfers[2].values, ctx->pgs->set_transfer.blue->values, transfer_map_size * sizeof(frac));
+    }
+    if (ctx->pgs->set_transfer.gray == 0x00) {
+        ctx->DefaultTransfers[3].proc = gs_identity_transfer;
+        memset(ctx->DefaultTransfers[3].values, 0x00, transfer_map_size * sizeof(frac));
+    } else {
+        ctx->DefaultTransfers[3].proc = ctx->pgs->set_transfer.gray->proc;
+        memcpy(ctx->DefaultTransfers[3].values, ctx->pgs->set_transfer.gray->values, transfer_map_size * sizeof(frac));
+    }
+    if (ctx->pgs->black_generation == 0x00) {
+        ctx->DefaultBG.proc = gs_identity_transfer;
+        memset(ctx->DefaultBG.values, 0x00, transfer_map_size * sizeof(frac));
+    } else {
+        ctx->DefaultBG.proc = ctx->pgs->black_generation->proc;
+        memcpy(ctx->DefaultBG.values, ctx->pgs->black_generation->values, transfer_map_size * sizeof(frac));
+    }
+    if (ctx->pgs->undercolor_removal == 0x00) {
+        ctx->DefaultUCR.proc = gs_identity_transfer;
+        memset(ctx->DefaultUCR.values, 0x00, transfer_map_size * sizeof(frac));
+    } else {
+        ctx->DefaultUCR.proc = ctx->pgs->undercolor_removal->proc;
+        memcpy(ctx->DefaultUCR.values, ctx->pgs->undercolor_removal->values, transfer_map_size * sizeof(frac));
+    }
+    dbgmprintf1(ctx->memory, "Current page transparency setting is %d\n", ctx->PageTransparencyArray[page_index] & page_bit ? 1 : 0);
+
+    /* Force NOTRANSPARENCY here if required, until we can get it working... */
+    ctx->page_has_transparency = ctx->PageTransparencyArray[page_index] & page_bit ? 1 : 0;
+
+    /* Set whether device needs OP support
+     * This needs to be before transparency device is pushed, if applicable
+     */
+    pdfi_trans_set_needs_OP(ctx);
+    pdfi_oc_init(ctx);
+
+    pdfi_gsave(ctx);
+
+    if (ctx->page_has_transparency) {
+        if (code >= 0) {
+            /* We don't retain the PDF14 device */
+            code = gs_push_pdf14trans_device(ctx->pgs, false, false);
+            if (code >= 0) {
+                if (page_group_known) {
+                    code = pdfi_trans_begin_page_group(ctx, page_dict, group_dict);
+                    /* If setting the page group failed for some reason, abandon the page group, but continue with the page */
+                    if (code < 0)
+                        page_group_known = false;
+                }
+            } else {
+                /* Couldn't push the transparency compositor.
+                 * This is probably fatal, but attempt to recover by abandoning transparency
+                 */
+                ctx->page_has_transparency = uses_transparency = false;
+            }
+        } else {
+            /* Couldn't gsave round the transparency compositor.
+             * This is probably fatal, but attempt to recover by abandoning transparency
+             */
+            ctx->page_has_transparency = uses_transparency = false;
+        }
+    }
+
+    /* Init a base_pgs graphics state for Patterns
+     * (this has to be after transparency device pushed, if applicable)
+     */
+    pdfi_set_DefaultQState(ctx, ctx->pgs);
+
+    /* Save the current stream state, for later cleanup, in a local variable */
+    local_save_stream_state(ctx, &local_entry_save);
+    initialise_stream_save(ctx);
+
+    code = pdfi_process_page_contents(ctx, page_dict);
+
+    /* Put our state back the way it was before we ran the contents
+     * and check if the stream had problems
+     */
+#ifdef PROBE_STREAMS
+    if (ctx->pgs->level > ctx->current_stream_save.gsave_level ||
+        pdfi_count_stack(ctx) > ctx->current_stream_save.stack_count)
+        code = ((pdf_context *)0)->first_page;
+#endif
+
+    cleanup_context_interpretation(ctx, &local_entry_save);
+    local_restore_stream_state(ctx, &local_entry_save);
+
+    if (ctx->page_has_transparency && page_group_known) {
+        code1 = pdfi_trans_end_group(ctx);
+    }
+
+    pdfi_countdown(ctx->CurrentPageDict);
+    ctx->CurrentPageDict = NULL;
+
+    if (ctx->page_has_transparency) {
+        if (code1 < 0) {
+            (void)gs_abort_pdf14trans_device(ctx->pgs);
+            goto exit1;
+        }
+
+        code = gs_pop_pdf14trans_device(ctx->pgs, false);
+        if (code < 0) {
+            goto exit1;
+        }
+    }
+
+ exit1:
+    pdfi_grestore(ctx);
+ exit2:
+    pdfi_countdown(page_dict);
+    pdfi_countdown(group_dict);
+
+    if (code == 0)
+        code = pl_finish_page(ctx->memory->gs_lib_ctx->top_of_system, ctx->pgs, 1, true);
+    return code;
+}
diff --git a/pdf/pdf_page.h b/pdf/pdf_page.h
index c1213e3..17ab3af 100644
--- a/pdf/pdf_page.h
+++ b/pdf/pdf_page.h
@@ -1,4 +1,4 @@
-/* Copyright (C) 2001-2018 Artifex Software, Inc.
+/* Copyright (C) 2001-2019 Artifex Software, Inc.
    All Rights Reserved.
 
    This software is provided AS-IS with no warranty, either express or
@@ -18,6 +18,6 @@
 #ifndef PDF_PAGE_OPERATORS
 #define PDF_PAGE_OPERATORS
 
-/* NOTE: used to have OC stuff here, moved to pdf_optcontent.h */
+int pdfi_page_render(pdf_context *ctx, uint64_t page_num);
 
 #endif
diff --git a/pdf/pdf_pattern.c b/pdf/pdf_pattern.c
index 00d396b..a6f965c 100644
--- a/pdf/pdf_pattern.c
+++ b/pdf/pdf_pattern.c
@@ -31,6 +31,7 @@
 #include "pdf_loop_detect.h"
 #include "pdf_func.h"
 #include "pdf_shading.h"
+#include "pdf_check.h"
 #include "gscsepr.h"
 #include "stream.h"
 #include "strmio.h"


Summary of changes:
 pdf/ghostpdf.c                   | 1433 +-------------------------------------
 pdf/ghostpdf.h                   |    3 -
 pdf/pdf.mak                      |    4 +
 pdf/pdf_check.c                  | 1043 +++++++++++++++++++++++++++
 base/gsstrl.h => pdf/pdf_check.h |   12 +-
 pdf/pdf_optcontent.c             |   20 +-
 pdf/pdf_optcontent.h             |    1 +
 pdf/pdf_page.c                   |  421 ++++++++++-
 pdf/pdf_page.h                   |    4 +-
 pdf/pdf_pattern.c                |    1 +
 10 files changed, 1489 insertions(+), 1453 deletions(-)
 create mode 100644 pdf/pdf_check.c
 copy base/gsstrl.h => pdf/pdf_check.h (65%)