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/* See LICENSE file for copyright and license details. */
#include <arpa/inet.h>
#include <errno.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <jpeglib.h>
static char *argv0;
METHODDEF(void)
jpeg_error(j_common_ptr js)
{
fprintf(stderr, "%s: libjpeg: ", argv0);
(*js->err->output_message)(js);
exit(1);
}
int
main(int argc, char *argv[])
{
struct jpeg_decompress_struct js;
struct jpeg_error_mgr jerr;
uint32_t width, height, tmp32;
uint16_t *row;
size_t rowlen, i;
JSAMPARRAY jpgrow;
argv0 = argv[0], argc--, argv++;
if (argc) {
fprintf(stderr, "usage: %s\n", argv0);
return 1;
}
/* load jpg */
js.err = jpeg_std_error(&jerr);
jerr.error_exit = jpeg_error;
jpeg_create_decompress(&js);
jpeg_stdio_src(&js, stdin);
jpeg_read_header(&js, 1);
width = js.image_width;
height = js.image_height;
/* set output format */
js.output_components = 3; /* color components per pixel */
js.out_color_space = JCS_RGB; /* input color space */
jpeg_start_decompress(&js);
/* create output buffers */
jpgrow = (*js.mem->alloc_sarray)((j_common_ptr)&js,
JPOOL_IMAGE, width *
js.output_components, 1);
rowlen = width * (sizeof("RGBA") - 1);
if(!(row = malloc(rowlen * sizeof(uint16_t)))) {
fprintf(stderr, "%s: malloc: out of memory\n", argv0);
return 1;
}
/* write header */
fputs("farbfeld", stdout);
tmp32 = htonl(width);
if (fwrite(&tmp32, sizeof(uint32_t), 1, stdout) != 1)
goto writerr;
tmp32 = htonl(height);
if (fwrite(&tmp32, sizeof(uint32_t), 1, stdout) != 1)
goto writerr;
while (js.output_scanline < js.output_height) {
/* jpeg_read_scanlines expects an array of pointers to
* scanlines.
* Here the array is only one element long, but you could
* ask for more than one scanline at a time if that's more
* convenient. */
jpeg_read_scanlines(&js, jpgrow, 1);
for (i = 0; i < width; ++i) {
row[4*i + 0] = htons(jpgrow[0][3*i + 0] * 257);
row[4*i + 1] = htons(jpgrow[0][3*i + 1] * 257);
row[4*i + 2] = htons(jpgrow[0][3*i + 2] * 257);
row[4*i + 3] = htons(65535);
}
/* write data */
if (fwrite(row, sizeof(uint16_t), rowlen, stdout) != rowlen)
goto writerr;
}
jpeg_finish_decompress(&js);
jpeg_destroy_decompress(&js);
return 0;
writerr:
fprintf(stderr, "%s: fwrite: ", argv0);
perror(NULL);
return 1;
}
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