/* * Copyright (c) 2001 Fabrice Bellard * * Permission is hereby granted, free of charge, to any person obtaining a copy * of this software and associated documentation files (the "Software"), to deal * in the Software without restriction, including without limitation the rights * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell * copies of the Software, and to permit persons to whom the Software is * furnished to do so, subject to the following conditions: * * The above copyright notice and this permission notice shall be included in * all copies or substantial portions of the Software. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN * THE SOFTWARE. */ /** * @file libavcodec video decoding API usage example * @example decode_video.c * * * Read from an MPEG1 video file, decode frames, and generate PGM images as * output. */ #include <stdio.h>#include <stdlib.h>#include <string.h> #include <libavcodec/avcodec.h> #define INBUF_SIZE 4096 static void pgm_save(unsigned char *buf, int wrap, int xsize, int ysize, char *filename){ FILE *f; int i; f = fopen(filename,"wb"); fprintf(f, "P5\n%d %d\n%d\n", xsize, ysize, 255); for (i = 0; i < ysize; i++) fwrite(buf + i * wrap, 1, xsize, f); fclose(f);} static void decode(AVCodecContext *dec_ctx, AVFrame *frame, AVPacket *pkt, const char *filename){ char buf[1024]; int ret; ret = avcodec_send_packet(dec_ctx, pkt); if (ret < 0) { fprintf(stderr, "Error sending a packet for decoding\n"); exit(1); } while (ret >= 0) { ret = avcodec_receive_frame(dec_ctx, frame); if (ret == AVERROR(EAGAIN) || ret == AVERROR_EOF) return; else if (ret < 0) { fprintf(stderr, "Error during decoding\n"); exit(1); } printf("saving frame %3"PRId64"\n", dec_ctx->frame_num); fflush(stdout); /* the picture is allocated by the decoder. no need to free it */ snprintf(buf, sizeof(buf), "%s-%"PRId64, filename, dec_ctx->frame_num); pgm_save(frame->data[0], frame->linesize[0], frame->width, frame->height, buf); }} int main(int argc, char **argv){ const char *filename, *outfilename; const AVCodec *codec; AVCodecParserContext *parser; AVCodecContext *c= NULL; FILE *f; AVFrame *frame; uint8_t inbuf[INBUF_SIZE + AV_INPUT_BUFFER_PADDING_SIZE]; uint8_t *data; size_t data_size; int ret; int eof; AVPacket *pkt; if (argc <= 2) { fprintf(stderr, "Usage: %s <input file> <output file>\n" "And check your input file is encoded by mpeg1video please.\n", argv[0]); exit(0); } filename = argv[1]; outfilename = argv[2]; pkt = av_packet_alloc(); if (!pkt) exit(1); /* set end of buffer to 0 (this ensures that no overreading happens for damaged MPEG streams) */ memset(inbuf + INBUF_SIZE, 0, AV_INPUT_BUFFER_PADDING_SIZE); /* find the MPEG-1 video decoder */ codec = avcodec_find_decoder(AV_CODEC_ID_MPEG1VIDEO); if (!codec) { fprintf(stderr, "Codec not found\n"); exit(1); } parser = av_parser_init(codec->id); if (!parser) { fprintf(stderr, "parser not found\n"); exit(1); } c = avcodec_alloc_context3(codec); if (!c) { fprintf(stderr, "Could not allocate video codec context\n"); exit(1); } /* For some codecs, such as msmpeg4 and mpeg4, width and height MUST be initialized there because this information is not available in the bitstream. */ /* open it */ if (avcodec_open2(c, codec, NULL) < 0) { fprintf(stderr, "Could not open codec\n"); exit(1); } f = fopen(filename, "rb"); if (!f) { fprintf(stderr, "Could not open %s\n", filename); exit(1); } frame = av_frame_alloc(); if (!frame) { fprintf(stderr, "Could not allocate video frame\n"); exit(1); } do { /* read raw data from the input file */ data_size = fread(inbuf, 1, INBUF_SIZE, f); if (ferror(f)) break; eof = !data_size; /* use the parser to split the data into frames */ data = inbuf; while (data_size > 0 || eof) { ret = av_parser_parse2(parser, c, &pkt->data, &pkt->size, data, data_size, AV_NOPTS_VALUE, AV_NOPTS_VALUE, 0); if (ret < 0) { fprintf(stderr, "Error while parsing\n"); exit(1); } data += ret; data_size -= ret; if (pkt->size) decode(c, frame, pkt, outfilename); else if (eof) break; } } while (!eof); /* flush the decoder */ decode(c, frame, NULL, outfilename); fclose(f); av_parser_close(parser); avcodec_free_context(&c); av_frame_free(&frame); av_packet_free(&pkt); return 0;}
/*
* Copyright (c) 2001 Fabrice Bellard
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
/**
* @file libavcodec video decoding API usage example
* @example decode_video.c *
*
* Read from an MPEG1 video file, decode frames, and generate PGM images as
* output.
*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <libavcodec/avcodec.h>
#define INBUF_SIZE 4096
static void pgm_save(unsigned char *buf, int wrap, int xsize, int ysize,
char *filename)
{
FILE *f;
int i;
f = fopen(filename,"wb");
fprintf(f, "P5\n%d %d\n%d\n", xsize, ysize, 255);
for (i = 0; i < ysize; i++)
fwrite(buf + i * wrap, 1, xsize, f);
fclose(f);
}
static void decode(AVCodecContext *dec_ctx, AVFrame *frame, AVPacket *pkt,
const char *filename)
{
char buf[1024];
int ret;
ret = avcodec_send_packet(dec_ctx, pkt);
if (ret < 0) {
fprintf(stderr, "Error sending a packet for decoding\n");
exit(1);
}
while (ret >= 0) {
ret = avcodec_receive_frame(dec_ctx, frame);
if (ret == AVERROR(EAGAIN) || ret == AVERROR_EOF)
return;
else if (ret < 0) {
fprintf(stderr, "Error during decoding\n");
exit(1);
}
printf("saving frame %3"PRId64"\n", dec_ctx->frame_num);
fflush(stdout);
/* the picture is allocated by the decoder. no need to
free it */
snprintf(buf, sizeof(buf), "%s-%"PRId64, filename, dec_ctx->frame_num);
pgm_save(frame->data[0], frame->linesize[0],
frame->width, frame->height, buf);
}
}
int main(int argc, char **argv)
{
const char *filename, *outfilename;
const AVCodec *codec;
AVCodecParserContext *parser;
AVCodecContext *c= NULL;
FILE *f;
AVFrame *frame;
uint8_t inbuf[INBUF_SIZE + AV_INPUT_BUFFER_PADDING_SIZE];
uint8_t *data;
size_t data_size;
int ret;
int eof;
AVPacket *pkt;
if (argc <= 2) {
fprintf(stderr, "Usage: %s <input file> <output file>\n"
"And check your input file is encoded by mpeg1video please.\n", argv[0]);
exit(0);
}
filename = argv[1];
outfilename = argv[2];
pkt = av_packet_alloc();
if (!pkt)
exit(1);
/* set end of buffer to 0 (this ensures that no overreading happens for damaged MPEG streams) */
memset(inbuf + INBUF_SIZE, 0, AV_INPUT_BUFFER_PADDING_SIZE);
/* find the MPEG-1 video decoder */
codec = avcodec_find_decoder(AV_CODEC_ID_MPEG1VIDEO);
if (!codec) {
fprintf(stderr, "Codec not found\n");
exit(1);
}
parser = av_parser_init(codec->id);
if (!parser) {
fprintf(stderr, "parser not found\n");
exit(1);
}
c = avcodec_alloc_context3(codec);
if (!c) {
fprintf(stderr, "Could not allocate video codec context\n");
exit(1);
}
/* For some codecs, such as msmpeg4 and mpeg4, width and height
MUST be initialized there because this information is not
available in the bitstream. */
/* open it */
if (avcodec_open2(c, codec, NULL) < 0) {
fprintf(stderr, "Could not open codec\n");
exit(1);
}
f = fopen(filename, "rb");
if (!f) {
fprintf(stderr, "Could not open %s\n", filename);
exit(1);
}
frame = av_frame_alloc();
if (!frame) {
fprintf(stderr, "Could not allocate video frame\n");
exit(1);
}
do {
/* read raw data from the input file */
data_size = fread(inbuf, 1, INBUF_SIZE, f);
if (ferror(f))
break;
eof = !data_size;
/* use the parser to split the data into frames */
data = inbuf;
while (data_size > 0 || eof) {
ret = av_parser_parse2(parser, c, &pkt->data, &pkt->size,
data, data_size, AV_NOPTS_VALUE, AV_NOPTS_VALUE, 0);
if (ret < 0) {
fprintf(stderr, "Error while parsing\n");
exit(1);
}
data += ret;
data_size -= ret;
if (pkt->size)
decode(c, frame, pkt, outfilename);
else if (eof)
break;
}
} while (!eof);
/* flush the decoder */
decode(c, frame, NULL, outfilename);
fclose(f);
av_parser_close(parser);
avcodec_free_context(&c);
av_frame_free(&frame);
av_packet_free(&pkt);
return 0;
}