jbig2dec

Update of /cvsroot/jbig2dec/jbig2dec
In directory usw-pr-cvs1:/tmp/cvs-serv14513

Modified Files:
	Makefile.am jbig2_generic.c jbig2_priv.h jbig2_segment.c 
	jbig2_symbol_dict.c 
Added Files:
	jbig2_text.c 
Log Message:
Beginnings of text segment handling. Parse (most of) the text region
segment header. Move the region segment info parser to jbig2_segment.c
and jbig2_priv.h since this is shared by all region segment types. 


--- NEW FILE: jbig2_text.c ---
/*
    jbig2dec
    
    Copyright (C) 2002 artofcode LLC.
    
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation; either version 2 of the License, or
    (at your option) any later version.

    $Id: jbig2_text.c,v 1.1 2002/06/20 15:42:48 giles Exp $
*/

#include <stddef.h>
#include <stdint.h>

#include "jbig2.h"
#include "jbig2_priv.h"
#include "jbig2_arith.h"
#include "jbig2_arith_int.h"
#include "jbig2_generic.h"
#include "jbig2_symbol_dict.h"

/**
 * jbig2_read_text_info: read a text region segment header
 **/
int
jbig2_read_text_info(Jbig2Ctx *ctx, Jbig2SegmentHeader *sh, const byte *segment_data)
{
    int offset = 0;
    Jbig2RegionSegmentInfo region_info;
    uint32_t num_instances;
    uint16_t segment_flags;
    uint16_t huffman_flags;
    int8_t sbrat[4];	/* FIXME: needs to be explicitly signed? */
    
    /* 7.4.1 */
    jbig2_get_region_segment_info(&region_info, segment_data);
    offset += 17;
    
    /* 7.4.3.1.1 */
    segment_flags = jbig2_get_int16(segment_data + offset);
    offset += 2;
    
    if (segment_flags & 1)	/* Huffman coding */
      {
        /* 7.4.3.1.2 */
        huffman_flags = jbig2_get_int16(segment_data + offset);
        offset += 2;
      }
    else	/* arithmetic coding */
      {
        /* 7.4.3.1.3 */
        if ((segment_flags & 0x02) && !(segment_flags & 0x80)) /* SBREFINE & !SBRTEMPLATE */
          {
            sbrat[0] = segment_data[offset];
            sbrat[0] = segment_data[offset + 1];
            sbrat[0] = segment_data[offset + 2];
            sbrat[0] = segment_data[offset + 3];
            offset += 4;
      }
    
    /* 7.4.3.1.4 */
    num_instances = jbig2_get_int32(segment_data + offset);
    offset += 4;
    
    /* 7.4.3.1.7 */
    if (segment_flags & 0x01) {
        jbig2_error(ctx, JBIG2_SEVERITY_WARNING, sh->segment_number,
            "symbol id huffman table decoding NYI");
    }
    
    jbig2_error(ctx, JBIG2_SEVERITY_INFO, sh->segment_number,
        "text region: %d x %d @ (%d,%d) %d symbols",
        region_info.width, region_info.height,
        region_info.x, region_info.y, num_instances);
    }
}
Index: Makefile.am
===================================================================
RCS file: /cvsroot/jbig2dec/jbig2dec/Makefile.am,v
retrieving revision 1.3
retrieving revision 1.4
diff -u -r1.3 -r1.4
--- Makefile.am	15 Jun 2002 16:02:53 -0000	1.3
+++ Makefile.am	20 Jun 2002 15:42:47 -0000	1.4
@@ -6,7 +6,7 @@
 libjbig2dec_a_SOURCES = jbig2.c \
 	jbig2_arith.c jbig2_arith_int.c jbig2_huffman.c \
 	jbig2_segment.c jbig2_page.c \
-	jbig2_symbol_dict.c \
+	jbig2_symbol_dict.c jbig2_text.c \
 	jbig2_generic.c jbig2_mmr.c \
 	jbig2_image.c jbig2_image_pbm.c
 

Index: jbig2_generic.c
===================================================================
RCS file: /cvsroot/jbig2dec/jbig2dec/jbig2_generic.c,v
retrieving revision 1.4
retrieving revision 1.5
diff -u -r1.4 -r1.5
--- jbig2_generic.c	25 Apr 2002 23:24:08 -0000	1.4
+++ jbig2_generic.c	20 Jun 2002 15:42:47 -0000	1.5
@@ -28,14 +28,6 @@
 #include "jbig2_generic.h"
 #include "jbig2_mmr.h"
 
-typedef struct {
-  int32_t width;
-  int32_t height;
-  int32_t x;
-  int32_t y;
-  byte flags;
-} Jbig2RegionSegmentInfo;
-
 static int
 jbig2_decode_generic_template0(Jbig2Ctx *ctx,
 			       int32_t seg_number,
@@ -358,18 +350,6 @@
 	      "decode_generic_region: MMR=%d, GBTEMPLATE=%d NYI",
 	      params->MMR, params->GBTEMPLATE);
   return -1;
-}
-
-void
-jbig2_get_region_segment_info(Jbig2RegionSegmentInfo *info,
-			      const byte *segment_data)
-{
-  /* 7.4.1 */
-  info->width = jbig2_get_int32(segment_data);
-  info->height = jbig2_get_int32(segment_data + 4);
-  info->x = jbig2_get_int32(segment_data + 8);
-  info->y = jbig2_get_int32(segment_data + 12);
-  info->flags = segment_data[16];
 }
 
 int

Index: jbig2_priv.h
===================================================================
RCS file: /cvsroot/jbig2dec/jbig2dec/jbig2_priv.h,v
retrieving revision 1.5
retrieving revision 1.6
diff -u -r1.5 -r1.6
--- jbig2_priv.h	18 Jun 2002 13:40:29 -0000	1.5
+++ jbig2_priv.h	20 Jun 2002 15:42:47 -0000	1.6
@@ -108,6 +108,18 @@
 int jbig2_read_page_info (Jbig2Ctx *ctx, Jbig2SegmentHeader *sh, const byte *segment_data);
 int jbig2_complete_page (Jbig2Ctx *ctx, Jbig2SegmentHeader *sh, const byte *segment_data);
 
+/* region segment info */
+
+typedef struct {
+  int32_t width;
+  int32_t height;
+  int32_t x;
+  int32_t y;
+  byte flags;
+} Jbig2RegionSegmentInfo;
+
+void jbig2_get_region_segment_info(Jbig2RegionSegmentInfo *info, const byte *segment_data);
+int jbig2_read_text_info(Jbig2Ctx *ctx, Jbig2SegmentHeader *sh, const byte *segment_data);
 
 /* The word stream design is a compromise between simplicity and
    trying to amortize the number of method calls. Each ::get_next_word

Index: jbig2_segment.c
===================================================================
RCS file: /cvsroot/jbig2dec/jbig2dec/jbig2_segment.c,v
retrieving revision 1.4
retrieving revision 1.5
diff -u -r1.4 -r1.5
--- jbig2_segment.c	18 Jun 2002 13:40:29 -0000	1.4
+++ jbig2_segment.c	20 Jun 2002 15:42:47 -0000	1.5
@@ -96,6 +96,18 @@
   jbig2_free (ctx->allocator, sh);
 }
 
+void
+jbig2_get_region_segment_info(Jbig2RegionSegmentInfo *info,
+			      const byte *segment_data)
+{
+  /* 7.4.1 */
+  info->width = jbig2_get_int32(segment_data);
+  info->height = jbig2_get_int32(segment_data + 4);
+  info->x = jbig2_get_int32(segment_data + 8);
+  info->y = jbig2_get_int32(segment_data + 12);
+  info->flags = segment_data[16];
+}
+
 int jbig2_write_segment (Jbig2Ctx *ctx, Jbig2SegmentHeader *sh,
 			 const uint8_t *segment_data)
 {
@@ -114,8 +126,7 @@
       return jbig2_error(ctx, JBIG2_SEVERITY_WARNING, sh->segment_number,
         "unhandled segment type 'immediate text region'");
     case 7:
-      return jbig2_error(ctx, JBIG2_SEVERITY_WARNING, sh->segment_number,
-        "unhandled segment type 'immediate lossless text region'");
+      return jbig2_read_text_info(ctx, sh, segment_data);
     case 16:
       return jbig2_error(ctx, JBIG2_SEVERITY_WARNING, sh->segment_number,
         "unhandled segment type 'pattern dictionary'");

Index: jbig2_symbol_dict.c
===================================================================
RCS file: /cvsroot/jbig2dec/jbig2dec/jbig2_symbol_dict.c,v
retrieving revision 1.4
retrieving revision 1.5
diff -u -r1.4 -r1.5
--- jbig2_symbol_dict.c	15 Jun 2002 14:12:50 -0000	1.4
+++ jbig2_symbol_dict.c	20 Jun 2002 15:42:48 -0000	1.5
@@ -114,7 +114,7 @@
   /* SDHUFFBMSIZE */
   /* SDHUFFAGGINST */
   int SDTEMPLATE;
-  int8_t sdat[8];
+  int8_t sdat[8]; 	// FIXME: do these need to be explicitly signed?
   bool SDRTEMPLATE;
   int8_t sdrat[4];
 } Jbig2SymbolDictParams;
@@ -259,8 +259,11 @@
   params.SDTEMPLATE = (flags >> 10) & 3;
   params.SDRTEMPLATE = (flags >> 12) & 1;
 
-  if (params.SDHUFF)
+  if (params.SDHUFF) {
+    jbig2_error(ctx, JBIG2_SEVERITY_WARNING, sh->segment_number,
+        "symbol dictionary uses the Huffman encoding variant (NYI)");
     return 0;
+  }
 
   /* FIXME: there are quite a few of these conditions to check */
   /* maybe #ifdef CONFORMANCE and a separate routine */
@@ -275,6 +278,12 @@
 		  "SDHUFF is zero, but contrary to spec SDHUFFDW is not.");
     }
 
+  if (flags & 0x0080)
+    {
+      jbig2_error(ctx, JBIG2_SEVERITY_WARNING, sh->segment_number,
+        "bitmap coding context is used (NYI) symbol data likely to be garbage!");
+    }
+
   /* 7.4.2.1.2 */
   sdat_bytes = params.SDHUFF ? 0 : params.SDTEMPLATE == 0 ? 8 : 2;
   memcpy(params.sdat, segment_data + 2, sdat_bytes);
@@ -309,6 +318,12 @@
 	params.SDTEMPLATE == 1 ? 8192 : 1024;
       GB_stats = jbig2_alloc(ctx->allocator, stats_size);
       memset(GB_stats, 0, stats_size);
+    }
+
+  if (flags & 0x0100)
+    {
+      jbig2_error(ctx, JBIG2_SEVERITY_WARNING, sh->segment_number,
+        "segment marks bitmap coding context as retained (NYI)");
     }
 
   return jbig2_decode_symbol_dict(ctx, sh->segment_number,