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examples/avcodec: split the remaining two examples into separate files

This commit is contained in:
Anton Khirnov 2016-10-19 21:05:22 +02:00
parent 90265814f9
commit 7b1f03477f
4 changed files with 192 additions and 166 deletions
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6
configure vendored
View File

@ -1209,9 +1209,10 @@ COMPONENT_LIST="
"
EXAMPLE_LIST="
avcodec_example
decode_audio_example
decode_video_example
encode_audio_example
encode_video_example
filter_audio_example
metadata_example
output_example
@ -2436,9 +2437,10 @@ scale_qsv_filter_deps="libmfx"
scale_vaapi_filter_deps="vaapi VAProcPipelineParameterBuffer"
# examples
avcodec_example_deps="avcodec avutil"
decode_audio_example_deps="avcodec avutil"
decode_video_example_deps="avcodec avutil"
encode_audio_example_deps="avcodec avutil"
encode_video_example_deps="avcodec avutil"
filter_audio_example_deps="avfilter avutil"
metadata_example_deps="avformat avutil"
output_example_deps="avcodec avformat avutil swscale"

12
doc/Makefile
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@ -16,16 +16,22 @@ DOCS-$(CONFIG_POD2MAN) += $(MANPAGES) $(PODPAGES)
DOCS-$(CONFIG_TEXI2HTML) += $(HTMLPAGES)
DOCS = $(DOCS-yes)
DOC_EXAMPLES-$(CONFIG_AVCODEC_EXAMPLE) += avcodec
DOC_EXAMPLES-$(CONFIG_DECODE_AUDIO_EXAMPLE) += decode_audio
DOC_EXAMPLES-$(CONFIG_DECODE_VIDEO_EXAMPLE) += decode_video
DOC_EXAMPLES-$(CONFIG_ENCODE_AUDIO_EXAMPLE) += encode_audio
DOC_EXAMPLES-$(CONFIG_ENCODE_VIDEO_EXAMPLE) += encode_video
DOC_EXAMPLES-$(CONFIG_FILTER_AUDIO_EXAMPLE) += filter_audio
DOC_EXAMPLES-$(CONFIG_METADATA_EXAMPLE) += metadata
DOC_EXAMPLES-$(CONFIG_OUTPUT_EXAMPLE) += output
DOC_EXAMPLES-$(CONFIG_QSVDEC_EXAMPLE) += qsvdec
DOC_EXAMPLES-$(CONFIG_TRANSCODE_AAC_EXAMPLE) += transcode_aac
ALL_DOC_EXAMPLES = avcodec decode_audio encode_audio filter_audio metadata \
output transcode_aac
ALL_DOC_EXAMPLES = decode_audio \
decode_video \
encode_audio \
encode_video \
filter_audio \
metadata output \
transcode_aac \
DOC_EXAMPLES := $(DOC_EXAMPLES-yes:%=doc/examples/%$(EXESUF))
ALL_DOC_EXAMPLES := $(ALL_DOC_EXAMPLES:%=doc/examples/%$(EXESUF))

176
doc/examples/avcodec.c → doc/examples/decode_video.c
View File

@ -20,159 +20,23 @@
/**
* @file
* libavcodec API use example.
* video decoding with libavcodec API example
*
* @example avcodec.c
* Note that this library only handles codecs (MPEG, MPEG-4, etc...),
* not file formats (AVI, VOB, etc...). See library 'libavformat' for the
* format handling.
* @example decode_video.c
*/
#include <stdlib.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#ifdef HAVE_AV_CONFIG_H
#undef HAVE_AV_CONFIG_H
#endif
#include "libavcodec/avcodec.h"
#include "libavutil/channel_layout.h"
#include "libavutil/common.h"
#include "libavutil/imgutils.h"
#include "libavutil/mathematics.h"
#include "libavutil/samplefmt.h"
#define INBUF_SIZE 4096
/*
* Video encoding example
*/
static void video_encode_example(const char *filename)
{
AVCodec *codec;
AVCodecContext *c= NULL;
int i, ret, x, y, got_output;
FILE *f;
AVFrame *picture;
AVPacket pkt;
uint8_t endcode[] = { 0, 0, 1, 0xb7 };
printf("Video encoding\n");
/* find the mpeg1video encoder */
codec = avcodec_find_encoder(AV_CODEC_ID_MPEG1VIDEO);
if (!codec) {
fprintf(stderr, "codec not found\n");
exit(1);
}
c = avcodec_alloc_context3(codec);
picture = av_frame_alloc();
/* put sample parameters */
c->bit_rate = 400000;
/* resolution must be a multiple of two */
c->width = 352;
c->height = 288;
/* frames per second */
c->time_base= (AVRational){1,25};
c->gop_size = 10; /* emit one intra frame every ten frames */
c->max_b_frames=1;
c->pix_fmt = AV_PIX_FMT_YUV420P;
/* open it */
if (avcodec_open2(c, codec, NULL) < 0) {
fprintf(stderr, "could not open codec\n");
exit(1);
}
f = fopen(filename, "wb");
if (!f) {
fprintf(stderr, "could not open %s\n", filename);
exit(1);
}
ret = av_image_alloc(picture->data, picture->linesize, c->width, c->height,
c->pix_fmt, 32);
if (ret < 0) {
fprintf(stderr, "could not alloc raw picture buffer\n");
exit(1);
}
picture->format = c->pix_fmt;
picture->width = c->width;
picture->height = c->height;
/* encode 1 second of video */
for(i=0;i<25;i++) {
av_init_packet(&pkt);
pkt.data = NULL; // packet data will be allocated by the encoder
pkt.size = 0;
fflush(stdout);
/* prepare a dummy image */
/* Y */
for(y=0;y<c->height;y++) {
for(x=0;x<c->width;x++) {
picture->data[0][y * picture->linesize[0] + x] = x + y + i * 3;
}
}
/* Cb and Cr */
for(y=0;y<c->height/2;y++) {
for(x=0;x<c->width/2;x++) {
picture->data[1][y * picture->linesize[1] + x] = 128 + y + i * 2;
picture->data[2][y * picture->linesize[2] + x] = 64 + x + i * 5;
}
}
picture->pts = i;
/* encode the image */
ret = avcodec_encode_video2(c, &pkt, picture, &got_output);
if (ret < 0) {
fprintf(stderr, "error encoding frame\n");
exit(1);
}
if (got_output) {
printf("encoding frame %3d (size=%5d)\n", i, pkt.size);
fwrite(pkt.data, 1, pkt.size, f);
av_packet_unref(&pkt);
}
}
/* get the delayed frames */
for (got_output = 1; got_output; i++) {
fflush(stdout);
ret = avcodec_encode_video2(c, &pkt, NULL, &got_output);
if (ret < 0) {
fprintf(stderr, "error encoding frame\n");
exit(1);
}
if (got_output) {
printf("encoding frame %3d (size=%5d)\n", i, pkt.size);
fwrite(pkt.data, 1, pkt.size, f);
av_packet_unref(&pkt);
}
}
/* add sequence end code to have a real MPEG file */
fwrite(endcode, 1, sizeof(endcode), f);
fclose(f);
avcodec_free_context(&c);
av_freep(&picture->data[0]);
av_frame_free(&picture);
printf("\n");
}
/*
* Video decoding example
*/
static void pgm_save(unsigned char *buf, int wrap, int xsize, int ysize,
char *filename)
{
@ -186,8 +50,9 @@ static void pgm_save(unsigned char *buf, int wrap, int xsize, int ysize,
fclose(f);
}
static void video_decode_example(const char *outfilename, const char *filename)
int main(int argc, char **argv)
{
const char *filename, *outfilename;
AVCodec *codec;
AVCodecContext *c= NULL;
int frame, got_picture, len;
@ -197,13 +62,20 @@ static void video_decode_example(const char *outfilename, const char *filename)
char buf[1024];
AVPacket avpkt;
if (argc <= 2) {
fprintf(stderr, "Usage: %s <input file> <output file>\n", argv[0]);
exit(0);
}
filename = argv[1];
outfilename = argv[2];
avcodec_register_all();
av_init_packet(&avpkt);
/* 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);
printf("Video decoding\n");
/* find the MPEG-1 video decoder */
codec = avcodec_find_decoder(AV_CODEC_ID_MPEG1VIDEO);
if (!codec) {
@ -301,24 +173,6 @@ static void video_decode_example(const char *outfilename, const char *filename)
avcodec_free_context(&c);
av_frame_free(&picture);
printf("\n");
}
int main(int argc, char **argv)
{
const char *filename;
/* register all the codecs */
avcodec_register_all();
if (argc <= 1) {
video_encode_example("/tmp/test.mpg");
filename = "/tmp/test.mpg";
} else {
filename = argv[1];
}
video_decode_example("/tmp/test%d.pgm", filename);
return 0;
}

164
doc/examples/encode_video.c Normal file
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@ -0,0 +1,164 @@
/*
* copyright (c) 2001 Fabrice Bellard
*
* This file is part of Libav.
*
* Libav is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* Libav 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
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with Libav; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
/**
* @file
* video encoding with libavcodec API example
*
* @example encode_video.c
*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "libavcodec/avcodec.h"
#include "libavutil/frame.h"
#include "libavutil/imgutils.h"
int main(int argc, char **argv)
{
const char *filename;
AVCodec *codec;
AVCodecContext *c= NULL;
int i, ret, x, y, got_output;
FILE *f;
AVFrame *picture;
AVPacket pkt;
uint8_t endcode[] = { 0, 0, 1, 0xb7 };
if (argc <= 1) {
fprintf(stderr, "Usage: %s <output file>\n", argv[0]);
exit(0);
}
filename = argv[1];
avcodec_register_all();
/* find the mpeg1video encoder */
codec = avcodec_find_encoder(AV_CODEC_ID_MPEG1VIDEO);
if (!codec) {
fprintf(stderr, "codec not found\n");
exit(1);
}
c = avcodec_alloc_context3(codec);
picture = av_frame_alloc();
/* put sample parameters */
c->bit_rate = 400000;
/* resolution must be a multiple of two */
c->width = 352;
c->height = 288;
/* frames per second */
c->time_base= (AVRational){1,25};
c->gop_size = 10; /* emit one intra frame every ten frames */
c->max_b_frames=1;
c->pix_fmt = AV_PIX_FMT_YUV420P;
/* open it */
if (avcodec_open2(c, codec, NULL) < 0) {
fprintf(stderr, "could not open codec\n");
exit(1);
}
f = fopen(filename, "wb");
if (!f) {
fprintf(stderr, "could not open %s\n", filename);
exit(1);
}
ret = av_image_alloc(picture->data, picture->linesize, c->width, c->height,
c->pix_fmt, 32);
if (ret < 0) {
fprintf(stderr, "could not alloc raw picture buffer\n");
exit(1);
}
picture->format = c->pix_fmt;
picture->width = c->width;
picture->height = c->height;
/* encode 1 second of video */
for(i=0;i<25;i++) {
av_init_packet(&pkt);
pkt.data = NULL; // packet data will be allocated by the encoder
pkt.size = 0;
fflush(stdout);
/* prepare a dummy image */
/* Y */
for(y=0;y<c->height;y++) {
for(x=0;x<c->width;x++) {
picture->data[0][y * picture->linesize[0] + x] = x + y + i * 3;
}
}
/* Cb and Cr */
for(y=0;y<c->height/2;y++) {
for(x=0;x<c->width/2;x++) {
picture->data[1][y * picture->linesize[1] + x] = 128 + y + i * 2;
picture->data[2][y * picture->linesize[2] + x] = 64 + x + i * 5;
}
}
picture->pts = i;
/* encode the image */
ret = avcodec_encode_video2(c, &pkt, picture, &got_output);
if (ret < 0) {
fprintf(stderr, "error encoding frame\n");
exit(1);
}
if (got_output) {
printf("encoding frame %3d (size=%5d)\n", i, pkt.size);
fwrite(pkt.data, 1, pkt.size, f);
av_packet_unref(&pkt);
}
}
/* get the delayed frames */
for (got_output = 1; got_output; i++) {
fflush(stdout);
ret = avcodec_encode_video2(c, &pkt, NULL, &got_output);
if (ret < 0) {
fprintf(stderr, "error encoding frame\n");
exit(1);
}
if (got_output) {
printf("encoding frame %3d (size=%5d)\n", i, pkt.size);
fwrite(pkt.data, 1, pkt.size, f);
av_packet_unref(&pkt);
}
}
/* add sequence end code to have a real MPEG file */
fwrite(endcode, 1, sizeof(endcode), f);
fclose(f);
avcodec_free_context(&c);
av_freep(&picture->data[0]);
av_frame_free(&picture);
return 0;
}