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#include <sys/stat.h>
#include <fcntl.h>
#include <unistd.h>
#include <stdlib.h>
#include <stdio.h>
#include "jpeg_rgb_decoder.h"
/* getfile */
void *getfile (char *path, int *n_bytes);
static void dump_pnm (unsigned char *ptr, int rowstride, int width, int height);
int
main (int argc, char *argv[])
{
unsigned char *data;
int len;
JpegRGBDecoder *dec;
char *fn;
unsigned char *ptr;
int rowstride;
int width;
int height;
dec = jpeg_rgb_decoder_new ();
if (argc < 2) {
printf("jpeg_rgb_test <file.jpg>\n");
exit(1);
}
fn = argv[1];
data = getfile (fn, &len);
if (data == NULL) {
printf("cannot read file %s\n", fn);
exit(1);
}
jpeg_rgb_decoder_addbits (dec, data, len);
jpeg_rgb_decoder_parse (dec);
jpeg_rgb_decoder_get_image (dec, &ptr, &rowstride, &width, &height);
dump_pnm (ptr, rowstride, width, height);
free (ptr);
jpeg_rgb_decoder_free (dec);
free (data);
return 0;
}
/* getfile */
void *
getfile (char *path, int *n_bytes)
{
int fd;
struct stat st;
void *ptr = NULL;
int ret;
fd = open (path, O_RDONLY);
if (!fd)
return NULL;
ret = fstat (fd, &st);
if (ret < 0) {
close (fd);
return NULL;
}
ptr = malloc (st.st_size);
if (!ptr) {
close (fd);
return NULL;
}
ret = read (fd, ptr, st.st_size);
if (ret != st.st_size) {
free (ptr);
close (fd);
return NULL;
}
if (n_bytes)
*n_bytes = st.st_size;
close (fd);
return ptr;
}
static void
dump_pnm (unsigned char *ptr, int rowstride, int width, int height)
{
int x, y;
printf ("P3\n");
printf ("%d %d\n", width, height);
printf ("255\n");
for (y = 0; y < height; y++) {
for (x = 0; x < width; x++) {
printf ("%d ", ptr[x * 4 + 2]);
printf ("%d ", ptr[x * 4 + 1]);
printf ("%d ", ptr[x * 4 + 0]);
if ((x & 15) == 15) {
printf ("\n");
}
}
printf ("\n");
ptr += rowstride;
}
}
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