Well this is odd but fun

Finally got back to this.  I made a very stripped down preview capture
program.  It works, but the file I get each time is the picture took
last time.  It's getting stored somewhere, maybe the camera's memory.
When I do gp_camera_capture_preview() and then gp_file_save() what
gets saved is the previous picture.  Then if I do it again I get the
picture I took the first time.  I want it for doing motion detection
so it's not unusable, just 1 frame delayed.  I haven't read a lot of
documentation, I just finally got a chance to play with it again.
Seems fast, my camera's giving me 320x240 images, just about what I
want.  The files get downloaded to my computer, looking at the camera
with gtkam I don't see any stale images hanging around.  I didn't
realize gtkam could do captures (right click in the left window on the
camera).

This needs to be linked with context.c and config.c

/*

  My Preview  Trying to capture preview images with libgphoto2

*/

// block of includes from preview.c
#include <unistd.h>
#include <stdlib.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <stdio.h>
#include <stdarg.h>
#include <string.h>
#include <gphoto2/gphoto2.h>
#include "samples.h"
#include <sys/time.h> // there's a gettimeofday somewhere


Camera  *canon;
GPContext *canoncontext;

void get_one(void) {  // capture 1 preview image
  CameraFile *file;
  char jpgname[] = "test2.jpg";
  int rslt;
  rslt  = gp_file_new(&file);
  if (rslt) {
    printf("Error creating new CameraFile %i\n",rslt);
    exit(1);
  }
  // skipping focus for now but do it here
  // skipping zoom also
  rslt = gp_camera_capture_preview(canon, file, canoncontext);
  if (rslt) {
    printf("error capturing preview %i\n",rslt);
    exit(1);
  }
  rslt = gp_file_save(file, jpgname);
  if (rslt) {
    printf("Error saving file (in gp_file_save) %i\n",rslt);
    exit(1);
  }
}

int main(void) {
  int rslt;
  // skip this for now
//  gp_log_add_func(GP_LOG_ERROR, errordumper, NULL);
  gp_camera_new(&canon);
  canoncontext =  sample_create_context();
  printf("Camera init.  Takes about 10 seconds.\n");
  rslt = gp_camera_init(canon, canoncontext);
  if (rslt) {
    printf("Error initializing camera %i\n",rslt);
    exit(1);
  }
  canon_enable_capture(canon, TRUE, canoncontext);  // in config.c
  get_one();
  gp_camera_exit(canon, canoncontext);
  return 0;
}
-- 
-------------
No, I won't  call it "climate change", do you have a "reality problem"? - AB1JX
Impeach  Impeach  Impeach  Impeach  Impeach  Impeach  Impeach  Impeach

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