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/*
* sample4.c
* Copyright (C) 2003 Regis Duchesne <hpreg@zoy.org>
* Copyright (C) 2000-2003 Michel Lespinasse <walken@zoy.org>
* Copyright (C) 1999-2000 Aaron Holtzman <aholtzma@ess.engr.uvic.ca>
*
* This file is part of mpeg2dec, a free MPEG-2 video stream decoder.
* See http://libmpeg2.sourceforge.net/ for updates.
*
* mpeg2dec 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.
*
* mpeg2dec is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*
* This program reads a MPEG-2 stream, and saves each of its frames as
* an image file using the PPM format (color).
*
* It demonstrates how to use the following features of libmpeg2:
* - Output buffers use the RGB 24-bit chunky format.
* - Output buffers are allocated by the caller but managed by the library.
*/
#include <stdio.h>
#include <stdlib.h>
#include <inttypes.h>
#include "mpeg2.h"
#include "mpeg2convert.h"
static void save_ppm (int width, int height, uint8_t * buf, int num)
{
char filename[100];
FILE * ppmfile;
sprintf (filename, "%d.ppm", num);
ppmfile = fopen (filename, "wb");
if (!ppmfile) {
fprintf (stderr, "Could not open file \"%s\".\n", filename);
exit (1);
}
fprintf (ppmfile, "P6\n%d %d\n255\n", width, height);
fwrite (buf, 3 * width, height, ppmfile);
fclose (ppmfile);
}
static void sample4 (FILE * mpgfile)
{
#define BUFFER_SIZE 4096
uint8_t buffer[BUFFER_SIZE];
mpeg2dec_t * decoder;
const mpeg2_info_t * info;
mpeg2_state_t state;
size_t size;
int framenum = 0;
int pixels;
uint8_t * fbuf[3][3];
int i;
decoder = mpeg2_init ();
if (decoder == NULL) {
fprintf (stderr, "Could not allocate a decoder object.\n");
exit (1);
}
info = mpeg2_info (decoder);
size = (size_t)-1;
do {
state = mpeg2_parse (decoder);
switch (state) {
case STATE_BUFFER:
size = fread (buffer, 1, BUFFER_SIZE, mpgfile);
mpeg2_buffer (decoder, buffer, buffer + size);
break;
case STATE_SEQUENCE:
mpeg2_convert (decoder, mpeg2convert_rgb24, NULL);
pixels = info->sequence->width * info->sequence->height;
for (i = 0; i < 3; i++) {
fbuf[i][0] = (uint8_t *) malloc (3 * pixels);
fbuf[i][1] = fbuf[i][2] = NULL;
if (!fbuf[i][0]) {
fprintf (stderr, "Could not allocate an output buffer.\n");
exit (1);
}
mpeg2_set_buf (decoder, fbuf[i], NULL);
}
break;
case STATE_SLICE:
case STATE_END:
case STATE_INVALID_END:
if (info->display_fbuf)
save_ppm (info->sequence->width, info->sequence->height,
info->display_fbuf->buf[0], framenum++);
if (state != STATE_SLICE)
for (i = 0; i < 3; i++)
free (fbuf[i][0]);
break;
default:
break;
}
} while (size);
mpeg2_close (decoder);
}
int main (int argc, char ** argv)
{
FILE * mpgfile;
if (argc > 1) {
mpgfile = fopen (argv[1], "rb");
if (!mpgfile) {
fprintf (stderr, "Could not open file \"%s\".\n", argv[1]);
exit (1);
}
} else
mpgfile = stdin;
sample4 (mpgfile);
return 0;
}
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