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1er avril 2013, par
Mis à jour : Avril 2013
Langue : français
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Video creation with the most recent ffmpeg API (2017)
19 octobre 2022, par ar2015I have started learning how to work with
ffmpegwhich has a suffering deprecation of all tutorial and available examples such as this.


I am looking for a code which creates an output video.



Unfortunately, most of good examples are focusing on reading from a file rather than creating one.



Here, I have found a deprecated example and I spent a long time to fix its errors until it became like this :



#include <iostream>
#include 
#include 
#include <string>

extern "C" {
 #include <libavcodec></libavcodec>avcodec.h>
 #include <libavformat></libavformat>avformat.h>
 #include <libswscale></libswscale>swscale.h>
 #include <libavformat></libavformat>avio.h>
 #include <libavutil></libavutil>opt.h>
}

#define WIDTH 800
#define HEIGHT 480
#define STREAM_NB_FRAMES ((int)(STREAM_DURATION * FRAME_RATE))
#define FRAME_RATE 24
#define PIXEL_FORMAT AV_PIX_FMT_YUV420P
#define STREAM_DURATION 5.0 //seconds
#define BIT_RATE 400000

#define AV_CODEC_FLAG_GLOBAL_HEADER (1 << 22)
#define CODEC_FLAG_GLOBAL_HEADER AV_CODEC_FLAG_GLOBAL_HEADER
#define AVFMT_RAWPICTURE 0x0020

using namespace std;

static int sws_flags = SWS_BICUBIC;

AVFrame *picture, *tmp_picture;
uint8_t *video_outbuf;
int frame_count, video_outbuf_size;


/****** IF LINUX ******/
inline int sprintf_s(char* buffer, size_t sizeOfBuffer, const char* format, ...)
{
 va_list ap;
 va_start(ap, format);
 int result = vsnprintf(buffer, sizeOfBuffer, format, ap);
 va_end(ap);
 return result;
}

/****** IF LINUX ******/
template
inline int sprintf_s(char (&buffer)[sizeOfBuffer], const char* format, ...)
{
 va_list ap;
 va_start(ap, format);
 int result = vsnprintf(buffer, sizeOfBuffer, format, ap);
 va_end(ap);
 return result;
}


static void closeVideo(AVFormatContext *oc, AVStream *st)
{
 avcodec_close(st->codec);
 av_free(picture->data[0]);
 av_free(picture);
 if (tmp_picture)
 {
 av_free(tmp_picture->data[0]);
 av_free(tmp_picture);
 }
 av_free(video_outbuf);
}

static AVFrame *alloc_picture(enum AVPixelFormat pix_fmt, int width, int height)
{
 AVFrame *picture;
 uint8_t *picture_buf;
 int size;

 picture = av_frame_alloc();
 if(!picture)
 return NULL;
 size = avpicture_get_size(pix_fmt, width, height);
 picture_buf = (uint8_t*)(av_malloc(size));
 if (!picture_buf)
 {
 av_free(picture);
 return NULL;
 }
 avpicture_fill((AVPicture *) picture, picture_buf, pix_fmt, WIDTH, HEIGHT);
 return picture;
}

static void openVideo(AVFormatContext *oc, AVStream *st)
{
 AVCodec *codec;
 AVCodecContext *c;

 c = st->codec;
 if(c->idct_algo == AV_CODEC_ID_H264)
 av_opt_set(c->priv_data, "preset", "slow", 0);

 codec = avcodec_find_encoder(c->codec_id);
 if(!codec)
 {
 std::cout << "Codec not found." << std::endl;
 std::cin.get();std::cin.get();exit(1);
 }

 if(codec->id == AV_CODEC_ID_H264)
 av_opt_set(c->priv_data, "preset", "medium", 0);

 if(avcodec_open2(c, codec, NULL) < 0)
 {
 std::cout << "Could not open codec." << std::endl;
 std::cin.get();std::cin.get();exit(1);
 }
 video_outbuf = NULL;
 if(!(oc->oformat->flags & AVFMT_RAWPICTURE))
 {
 video_outbuf_size = 200000;
 video_outbuf = (uint8_t*)(av_malloc(video_outbuf_size));
 }
 picture = alloc_picture(c->pix_fmt, c->width, c->height);
 if(!picture)
 {
 std::cout << "Could not allocate picture" << std::endl;
 std::cin.get();exit(1);
 }
 tmp_picture = NULL;
 if(c->pix_fmt != AV_PIX_FMT_YUV420P)
 {
 tmp_picture = alloc_picture(AV_PIX_FMT_YUV420P, WIDTH, HEIGHT);
 if(!tmp_picture)
 {
 std::cout << " Could not allocate temporary picture" << std::endl;
 std::cin.get();exit(1);
 }
 }
}


static AVStream* addVideoStream(AVFormatContext *context, enum AVCodecID codecID)
{
 AVCodecContext *codec;
 AVStream *stream;
 stream = avformat_new_stream(context, NULL);
 if(!stream)
 {
 std::cout << "Could not alloc stream." << std::endl;
 std::cin.get();exit(1);
 }

 codec = stream->codec;
 codec->codec_id = codecID;
 codec->codec_type = AVMEDIA_TYPE_VIDEO;

 // sample rate
 codec->bit_rate = BIT_RATE;
 // resolution must be a multiple of two
 codec->width = WIDTH;
 codec->height = HEIGHT;
 codec->time_base.den = FRAME_RATE; // stream fps
 codec->time_base.num = 1;
 codec->gop_size = 12; // intra frame every twelve frames at most
 codec->pix_fmt = PIXEL_FORMAT;
 if(codec->codec_id == AV_CODEC_ID_MPEG2VIDEO)
 codec->max_b_frames = 2; // for testing, B frames

 if(codec->codec_id == AV_CODEC_ID_MPEG1VIDEO)
 codec->mb_decision = 2;

 if(context->oformat->flags & AVFMT_GLOBALHEADER)
 codec->flags |= AV_CODEC_FLAG_GLOBAL_HEADER;

 return stream;
}

static void fill_yuv_image(AVFrame *pict, int frame_index, int width, int height)
{
 int x, y, i;
 i = frame_index;

 /* Y */
 for(y=0;ydata[0][y * pict->linesize[0] + x] = x + y + i * 3;
 }
 }

 /* Cb and Cr */
 for(y=0;y<height></height>2;y++) {
 for(x=0;x<width></width>2;x++) {
 pict->data[1][y * pict->linesize[1] + x] = 128 + y + i * 2;
 pict->data[2][y * pict->linesize[2] + x] = 64 + x + i * 5;
 }
 }
}

static void write_video_frame(AVFormatContext *oc, AVStream *st)
{
 int out_size, ret;
 AVCodecContext *c;
 static struct SwsContext *img_convert_ctx;
 c = st->codec;

 if(frame_count >= STREAM_NB_FRAMES)
 {

 }
 else
 {
 if(c->pix_fmt != AV_PIX_FMT_YUV420P)
 {
 if(img_convert_ctx = NULL)
 {
 img_convert_ctx = sws_getContext(WIDTH, HEIGHT, AV_PIX_FMT_YUV420P, WIDTH, HEIGHT,
 c->pix_fmt, sws_flags, NULL, NULL, NULL);
 if(img_convert_ctx == NULL)
 {
 std::cout << "Cannot initialize the conversion context" << std::endl;
 std::cin.get();exit(1);
 }
 }
 fill_yuv_image(tmp_picture, frame_count, WIDTH, HEIGHT);
 sws_scale(img_convert_ctx, tmp_picture->data, tmp_picture->linesize, 0, HEIGHT,
 picture->data, picture->linesize);
 }
 else
 {
 fill_yuv_image(picture, frame_count, WIDTH, HEIGHT);
 }
 }

 if (oc->oformat->flags & AVFMT_RAWPICTURE)
 {
 /* raw video case. The API will change slightly in the near
 futur for that */
 AVPacket pkt;
 av_init_packet(&pkt);

 pkt.flags |= AV_PKT_FLAG_KEY;
 pkt.stream_index= st->index;
 pkt.data= (uint8_t *)picture;
 pkt.size= sizeof(AVPicture);

 ret = av_interleaved_write_frame(oc, &pkt);
 }
 else
 {
 /* encode the image */
 out_size = avcodec_encode_video(c, video_outbuf, video_outbuf_size, picture);
 /* if zero size, it means the image was buffered */
 if (out_size > 0)
 {
 AVPacket pkt;
 av_init_packet(&pkt);

 if (c->coded_frame->pts != AV_NOPTS_VALUE)
 pkt.pts= av_rescale_q(c->coded_frame->pts, c->time_base, st->time_base);
 if(c->coded_frame->key_frame)
 pkt.flags |= AV_PKT_FLAG_KEY;
 pkt.stream_index= st->index;
 pkt.data= video_outbuf;
 pkt.size= out_size;
 /* write the compressed frame in the media file */
 ret = av_interleaved_write_frame(oc, &pkt);
 } else {
 ret = 0;
 }
 }
 if (ret != 0) {
 std::cout << "Error while writing video frames" << std::endl;
 std::cin.get();exit(1);
 }
 frame_count++;
}

int main ( int argc, char *argv[] )
{
 const char* filename = "test.h264";
 AVOutputFormat *outputFormat;
 AVFormatContext *context;
 AVCodecContext *codec;
 AVStream *videoStream;
 double videoPTS;

 // init libavcodec, register all codecs and formats
 av_register_all(); 
 // auto detect the output format from the name
 outputFormat = av_guess_format(NULL, filename, NULL);
 if(!outputFormat)
 {
 std::cout << "Cannot guess output format! Using mpeg!" << std::endl;
 std::cin.get();
 outputFormat = av_guess_format(NULL, "h263" , NULL);
 }
 if(!outputFormat)
 {
 std::cout << "Could not find suitable output format." << std::endl;
 std::cin.get();exit(1);
 }

 context = avformat_alloc_context();
 if(!context)
 {
 std::cout << "Cannot allocate avformat memory." << std::endl;
 std::cin.get();exit(1);
 }
 context->oformat = outputFormat;
 sprintf_s(context->filename, sizeof(context->filename), "%s", filename);
 std::cout << "Is '" << context->filename << "' = '" << filename << "'" << std::endl;


 videoStream = NULL;
 outputFormat->audio_codec = AV_CODEC_ID_NONE;
 videoStream = addVideoStream(context, outputFormat->video_codec);

 /* still needed?
 if(av_set_parameters(context, NULL) < 0)
 {
 std::cout << "Invalid output format parameters." << std::endl;
 exit(0);
 }*/

 av_dump_format(context, 0, filename, 1);

 if(videoStream)
 openVideo(context, videoStream);

 if(!outputFormat->flags & AVFMT_NOFILE)
 {
 if(avio_open(&context->pb, filename, AVIO_FLAG_READ_WRITE) < 0)
 {
 std::cout << "Could not open " << filename << std::endl;
 std::cin.get();exit(1);
 }
 }

 avformat_write_header(context, 0);

 while(true)
 {
 if(videoStream)
 videoPTS = (double) videoStream->pts.val * videoStream->time_base.num / videoStream->time_base.den;
 else
 videoPTS = 0.;

 if((!videoStream || videoPTS >= STREAM_DURATION))
 {
 break;
 }
 write_video_frame(context, videoStream);
 }
 av_write_trailer(context);
 if(videoStream)
 closeVideo(context, videoStream);
 for(int i = 0; i < context->nb_streams; i++)
 {
 av_freep(&context->streams[i]->codec);
 av_freep(&context->streams[i]);
 }

 if(!(outputFormat->flags & AVFMT_NOFILE))
 {
 avio_close(context->pb);
 }
 av_free(context);
 std::cin.get();
 return 0;
}
</string></iostream>


Compile :



g++ -I ./FFmpeg/ video.cpp -L fflibs -lavcodec -lavformat



The code comes with two errors :



video.cpp:249:84: error: ‘avcodec_encode_video’ was not declared in this scope
 out_size = avcodec_encode_video(c, video_outbuf, video_outbuf_size, picture);
 ^


video.cpp: In function ‘int main(int, char**)’:
video.cpp:342:46: error: ‘AVStream {aka struct AVStream}’ has no member named ‘pts’
 videoPTS = (double) videoStream->pts.val * videoStream->time_base.num / videoStream->time_base.den;
 ^



and a huge number of warnings for deprecation.



video.cpp: In function ‘void closeVideo(AVFormatContext*, AVStream*)’:
video.cpp:60:23: warning: ‘AVStream::codec’ is deprecated [-Wdeprecated-declarations]
 avcodec_close(st->codec);
 ^
In file included from video.cpp:9:0:
./FFmpeg/libavformat/avformat.h:876:21: note: declared here
 AVCodecContext *codec;
 ^
video.cpp:60:23: warning: ‘AVStream::codec’ is deprecated [-Wdeprecated-declarations]
 avcodec_close(st->codec);
 ^
In file included from video.cpp:9:0:
./FFmpeg/libavformat/avformat.h:876:21: note: declared here
 AVCodecContext *codec;
 ^
video.cpp:60:23: warning: ‘AVStream::codec’ is deprecated [-Wdeprecated-declarations]
 avcodec_close(st->codec);
 ^
In file included from video.cpp:9:0:
./FFmpeg/libavformat/avformat.h:876:21: note: declared here
 AVCodecContext *codec;
 ^
video.cpp: In function ‘AVFrame* alloc_picture(AVPixelFormat, int, int)’:
video.cpp:80:12: warning: ‘int avpicture_get_size(AVPixelFormat, int, int)’ is deprecated [-Wdeprecated-declarations]
 size = avpicture_get_size(pix_fmt, width, height);
 ^
In file included from video.cpp:8:0:
./FFmpeg/libavcodec/avcodec.h:5228:5: note: declared here
 int avpicture_get_size(enum AVPixelFormat pix_fmt, int width, int height);
 ^
video.cpp:80:12: warning: ‘int avpicture_get_size(AVPixelFormat, int, int)’ is deprecated [-Wdeprecated-declarations]
 size = avpicture_get_size(pix_fmt, width, height);
 ^
In file included from video.cpp:8:0:
./FFmpeg/libavcodec/avcodec.h:5228:5: note: declared here
 int avpicture_get_size(enum AVPixelFormat pix_fmt, int width, int height);
 ^
video.cpp:80:53: warning: ‘int avpicture_get_size(AVPixelFormat, int, int)’ is deprecated [-Wdeprecated-declarations]
 size = avpicture_get_size(pix_fmt, width, height);
 ^
In file included from video.cpp:8:0:
./FFmpeg/libavcodec/avcodec.h:5228:5: note: declared here
 int avpicture_get_size(enum AVPixelFormat pix_fmt, int width, int height);
 ^
video.cpp:87:5: warning: ‘int avpicture_fill(AVPicture*, const uint8_t*, AVPixelFormat, int, int)’ is deprecated [-Wdeprecated-declarations]
 avpicture_fill((AVPicture *) picture, picture_buf, pix_fmt, WIDTH, HEIGHT);
 ^
In file included from video.cpp:8:0:
./FFmpeg/libavcodec/avcodec.h:5213:5: note: declared here
 int avpicture_fill(AVPicture *picture, const uint8_t *ptr,
 ^
video.cpp:87:5: warning: ‘int avpicture_fill(AVPicture*, const uint8_t*, AVPixelFormat, int, int)’ is deprecated [-Wdeprecated-declarations]
 avpicture_fill((AVPicture *) picture, picture_buf, pix_fmt, WIDTH, HEIGHT);
 ^
In file included from video.cpp:8:0:
./FFmpeg/libavcodec/avcodec.h:5213:5: note: declared here
 int avpicture_fill(AVPicture *picture, const uint8_t *ptr,
 ^
video.cpp:87:78: warning: ‘int avpicture_fill(AVPicture*, const uint8_t*, AVPixelFormat, int, int)’ is deprecated [-Wdeprecated-declarations]
 avpicture_fill((AVPicture *) picture, picture_buf, pix_fmt, WIDTH, HEIGHT);
 ^
In file included from video.cpp:8:0:
./FFmpeg/libavcodec/avcodec.h:5213:5: note: declared here
 int avpicture_fill(AVPicture *picture, const uint8_t *ptr,
 ^
video.cpp: In function ‘void openVideo(AVFormatContext*, AVStream*)’:
video.cpp:96:13: warning: ‘AVStream::codec’ is deprecated [-Wdeprecated-declarations]
 c = st->codec;
 ^
In file included from video.cpp:9:0:
./FFmpeg/libavformat/avformat.h:876:21: note: declared here
 AVCodecContext *codec;
 ^
video.cpp:96:13: warning: ‘AVStream::codec’ is deprecated [-Wdeprecated-declarations]
 c = st->codec;
 ^
In file included from video.cpp:9:0:
./FFmpeg/libavformat/avformat.h:876:21: note: declared here
 AVCodecContext *codec;
 ^
video.cpp:96:13: warning: ‘AVStream::codec’ is deprecated [-Wdeprecated-declarations]
 c = st->codec;
 ^
In file included from video.cpp:9:0:
./FFmpeg/libavformat/avformat.h:876:21: note: declared here
 AVCodecContext *codec;
 ^
video.cpp: In function ‘AVStream* addVideoStream(AVFormatContext*, AVCodecID)’:
video.cpp:151:21: warning: ‘AVStream::codec’ is deprecated [-Wdeprecated-declarations]
 codec = stream->codec;
 ^
In file included from video.cpp:9:0:
./FFmpeg/libavformat/avformat.h:876:21: note: declared here
 AVCodecContext *codec;
 ^
video.cpp:151:21: warning: ‘AVStream::codec’ is deprecated [-Wdeprecated-declarations]
 codec = stream->codec;
 ^
In file included from video.cpp:9:0:
./FFmpeg/libavformat/avformat.h:876:21: note: declared here
 AVCodecContext *codec;
 ^
video.cpp:151:21: warning: ‘AVStream::codec’ is deprecated [-Wdeprecated-declarations]
 codec = stream->codec;
 ^
In file included from video.cpp:9:0:
./FFmpeg/libavformat/avformat.h:876:21: note: declared here
 AVCodecContext *codec;
 ^
video.cpp: In function ‘void write_video_frame(AVFormatContext*, AVStream*)’:
video.cpp:202:13: warning: ‘AVStream::codec’ is deprecated [-Wdeprecated-declarations]
 c = st->codec;
 ^
In file included from video.cpp:9:0:
./FFmpeg/libavformat/avformat.h:876:21: note: declared here
 AVCodecContext *codec;
 ^
video.cpp:202:13: warning: ‘AVStream::codec’ is deprecated [-Wdeprecated-declarations]
 c = st->codec;
 ^
In file included from video.cpp:9:0:
./FFmpeg/libavformat/avformat.h:876:21: note: declared here
 AVCodecContext *codec;
 ^
video.cpp:202:13: warning: ‘AVStream::codec’ is deprecated [-Wdeprecated-declarations]
 c = st->codec;
 ^
In file included from video.cpp:9:0:
./FFmpeg/libavformat/avformat.h:876:21: note: declared here
 AVCodecContext *codec;
 ^
video.cpp:256:20: warning: ‘AVCodecContext::coded_frame’ is deprecated [-Wdeprecated-declarations]
 if (c->coded_frame->pts != AV_NOPTS_VALUE)
 ^
In file included from video.cpp:8:0:
./FFmpeg/libavcodec/avcodec.h:2723:35: note: declared here
 attribute_deprecated AVFrame *coded_frame;
 ^
video.cpp:256:20: warning: ‘AVCodecContext::coded_frame’ is deprecated [-Wdeprecated-declarations]
 if (c->coded_frame->pts != AV_NOPTS_VALUE)
 ^
In file included from video.cpp:8:0:
./FFmpeg/libavcodec/avcodec.h:2723:35: note: declared here
 attribute_deprecated AVFrame *coded_frame;
 ^
video.cpp:256:20: warning: ‘AVCodecContext::coded_frame’ is deprecated [-Wdeprecated-declarations]
 if (c->coded_frame->pts != AV_NOPTS_VALUE)
 ^
In file included from video.cpp:8:0:
./FFmpeg/libavcodec/avcodec.h:2723:35: note: declared here
 attribute_deprecated AVFrame *coded_frame;
 ^
video.cpp:257:42: warning: ‘AVCodecContext::coded_frame’ is deprecated [-Wdeprecated-declarations]
 pkt.pts= av_rescale_q(c->coded_frame->pts, c->time_base, st->time_base);
 ^
In file included from video.cpp:8:0:
./FFmpeg/libavcodec/avcodec.h:2723:35: note: declared here
 attribute_deprecated AVFrame *coded_frame;
 ^
video.cpp:257:42: warning: ‘AVCodecContext::coded_frame’ is deprecated [-Wdeprecated-declarations]
 pkt.pts= av_rescale_q(c->coded_frame->pts, c->time_base, st->time_base);
 ^
In file included from video.cpp:8:0:
./FFmpeg/libavcodec/avcodec.h:2723:35: note: declared here
 attribute_deprecated AVFrame *coded_frame;
 ^
video.cpp:257:42: warning: ‘AVCodecContext::coded_frame’ is deprecated [-Wdeprecated-declarations]
 pkt.pts= av_rescale_q(c->coded_frame->pts, c->time_base, st->time_base);
 ^
In file included from video.cpp:8:0:
./FFmpeg/libavcodec/avcodec.h:2723:35: note: declared here
 attribute_deprecated AVFrame *coded_frame;
 ^
video.cpp:258:19: warning: ‘AVCodecContext::coded_frame’ is deprecated [-Wdeprecated-declarations]
 if(c->coded_frame->key_frame)
 ^
In file included from video.cpp:8:0:
./FFmpeg/libavcodec/avcodec.h:2723:35: note: declared here
 attribute_deprecated AVFrame *coded_frame;
 ^
video.cpp:258:19: warning: ‘AVCodecContext::coded_frame’ is deprecated [-Wdeprecated-declarations]
 if(c->coded_frame->key_frame)
 ^
In file included from video.cpp:8:0:
./FFmpeg/libavcodec/avcodec.h:2723:35: note: declared here
 attribute_deprecated AVFrame *coded_frame;
 ^
video.cpp:258:19: warning: ‘AVCodecContext::coded_frame’ is deprecated [-Wdeprecated-declarations]
 if(c->coded_frame->key_frame)
 ^
In file included from video.cpp:8:0:
./FFmpeg/libavcodec/avcodec.h:2723:35: note: declared here
 attribute_deprecated AVFrame *coded_frame;
 ^
video.cpp:357:40: warning: ‘AVStream::codec’ is deprecated [-Wdeprecated-declarations]
 av_freep(&context->streams[i]->codec);
 ^
In file included from video.cpp:9:0:
./FFmpeg/libavformat/avformat.h:876:21: note: declared here
 AVCodecContext *codec;
 ^
video.cpp:357:40: warning: ‘AVStream::codec’ is deprecated [-Wdeprecated-declarations]
 av_freep(&context->streams[i]->codec);
 ^
In file included from video.cpp:9:0:
./FFmpeg/libavformat/avformat.h:876:21: note: declared here
 AVCodecContext *codec;
 ^
video.cpp:357:40: warning: ‘AVStream::codec’ is deprecated [-Wdeprecated-declarations]
 av_freep(&context->streams[i]->codec);
 ^
In file included from video.cpp:9:0:
./FFmpeg/libavformat/avformat.h:876:21: note: declared here
 AVCodecContext *codec;
 ^
video.cpp:337:38: warning: ignoring return value of ‘int avformat_write_header(AVFormatContext*, AVDictionary**)’, declared with attribute warn_unused_result [-Wunused-result]
 avformat_write_header(context, 0);
 ^



I have also defined a few macros to redefine those who have been omited. In a modern
ffmpegAPI, they must be replaced.


Could someone please help me solving errors and deprecation warnings to comply with recent
ffmpegAPI ?

-
Video creation with a recent ffmpeg API (2017)
16 novembre 2017, par ar2015I have started learning how to work with
ffmpegwhich has a suffering deprecation of all tutorial and available examples such as this.I am looking for a code which creates an output video.
Unfortunately, most of good examples are focusing on reading from a file rather than creating one.
Here, I have found a deprecated example and I spent a long time to fix its errors until it became like this :
#include <iostream>
#include
#include
#include <string>
extern "C" {
#include <libavcodec></libavcodec>avcodec.h>
#include <libavformat></libavformat>avformat.h>
#include <libswscale></libswscale>swscale.h>
#include <libavformat></libavformat>avio.h>
#include <libavutil></libavutil>opt.h>
}
#define WIDTH 800
#define HEIGHT 480
#define STREAM_NB_FRAMES ((int)(STREAM_DURATION * FRAME_RATE))
#define FRAME_RATE 24
#define PIXEL_FORMAT AV_PIX_FMT_YUV420P
#define STREAM_DURATION 5.0 //seconds
#define BIT_RATE 400000
#define AV_CODEC_FLAG_GLOBAL_HEADER (1 << 22)
#define CODEC_FLAG_GLOBAL_HEADER AV_CODEC_FLAG_GLOBAL_HEADER
#define AVFMT_RAWPICTURE 0x0020
using namespace std;
static int sws_flags = SWS_BICUBIC;
AVFrame *picture, *tmp_picture;
uint8_t *video_outbuf;
int frame_count, video_outbuf_size;
/****** IF LINUX ******/
inline int sprintf_s(char* buffer, size_t sizeOfBuffer, const char* format, ...)
{
va_list ap;
va_start(ap, format);
int result = vsnprintf(buffer, sizeOfBuffer, format, ap);
va_end(ap);
return result;
}
/****** IF LINUX ******/
template
inline int sprintf_s(char (&buffer)[sizeOfBuffer], const char* format, ...)
{
va_list ap;
va_start(ap, format);
int result = vsnprintf(buffer, sizeOfBuffer, format, ap);
va_end(ap);
return result;
}
static void closeVideo(AVFormatContext *oc, AVStream *st)
{
avcodec_close(st->codec);
av_free(picture->data[0]);
av_free(picture);
if (tmp_picture)
{
av_free(tmp_picture->data[0]);
av_free(tmp_picture);
}
av_free(video_outbuf);
}
static AVFrame *alloc_picture(enum AVPixelFormat pix_fmt, int width, int height)
{
AVFrame *picture;
uint8_t *picture_buf;
int size;
picture = av_frame_alloc();
if(!picture)
return NULL;
size = avpicture_get_size(pix_fmt, width, height);
picture_buf = (uint8_t*)(av_malloc(size));
if (!picture_buf)
{
av_free(picture);
return NULL;
}
avpicture_fill((AVPicture *) picture, picture_buf, pix_fmt, WIDTH, HEIGHT);
return picture;
}
static void openVideo(AVFormatContext *oc, AVStream *st)
{
AVCodec *codec;
AVCodecContext *c;
c = st->codec;
if(c->idct_algo == AV_CODEC_ID_H264)
av_opt_set(c->priv_data, "preset", "slow", 0);
codec = avcodec_find_encoder(c->codec_id);
if(!codec)
{
std::cout << "Codec not found." << std::endl;
std::cin.get();std::cin.get();exit(1);
}
if(codec->id == AV_CODEC_ID_H264)
av_opt_set(c->priv_data, "preset", "medium", 0);
if(avcodec_open2(c, codec, NULL) < 0)
{
std::cout << "Could not open codec." << std::endl;
std::cin.get();std::cin.get();exit(1);
}
video_outbuf = NULL;
if(!(oc->oformat->flags & AVFMT_RAWPICTURE))
{
video_outbuf_size = 200000;
video_outbuf = (uint8_t*)(av_malloc(video_outbuf_size));
}
picture = alloc_picture(c->pix_fmt, c->width, c->height);
if(!picture)
{
std::cout << "Could not allocate picture" << std::endl;
std::cin.get();exit(1);
}
tmp_picture = NULL;
if(c->pix_fmt != AV_PIX_FMT_YUV420P)
{
tmp_picture = alloc_picture(AV_PIX_FMT_YUV420P, WIDTH, HEIGHT);
if(!tmp_picture)
{
std::cout << " Could not allocate temporary picture" << std::endl;
std::cin.get();exit(1);
}
}
}
static AVStream* addVideoStream(AVFormatContext *context, enum AVCodecID codecID)
{
AVCodecContext *codec;
AVStream *stream;
stream = avformat_new_stream(context, NULL);
if(!stream)
{
std::cout << "Could not alloc stream." << std::endl;
std::cin.get();exit(1);
}
codec = stream->codec;
codec->codec_id = codecID;
codec->codec_type = AVMEDIA_TYPE_VIDEO;
// sample rate
codec->bit_rate = BIT_RATE;
// resolution must be a multiple of two
codec->width = WIDTH;
codec->height = HEIGHT;
codec->time_base.den = FRAME_RATE; // stream fps
codec->time_base.num = 1;
codec->gop_size = 12; // intra frame every twelve frames at most
codec->pix_fmt = PIXEL_FORMAT;
if(codec->codec_id == AV_CODEC_ID_MPEG2VIDEO)
codec->max_b_frames = 2; // for testing, B frames
if(codec->codec_id == AV_CODEC_ID_MPEG1VIDEO)
codec->mb_decision = 2;
if(context->oformat->flags & AVFMT_GLOBALHEADER)
codec->flags |= AV_CODEC_FLAG_GLOBAL_HEADER;
return stream;
}
static void fill_yuv_image(AVFrame *pict, int frame_index, int width, int height)
{
int x, y, i;
i = frame_index;
/* Y */
for(y=0;ydata[0][y * pict->linesize[0] + x] = x + y + i * 3;
}
}
/* Cb and Cr */
for(y=0;y<height></height>2;y++) {
for(x=0;x<width></width>2;x++) {
pict->data[1][y * pict->linesize[1] + x] = 128 + y + i * 2;
pict->data[2][y * pict->linesize[2] + x] = 64 + x + i * 5;
}
}
}
static void write_video_frame(AVFormatContext *oc, AVStream *st)
{
int out_size, ret;
AVCodecContext *c;
static struct SwsContext *img_convert_ctx;
c = st->codec;
if(frame_count >= STREAM_NB_FRAMES)
{
}
else
{
if(c->pix_fmt != AV_PIX_FMT_YUV420P)
{
if(img_convert_ctx = NULL)
{
img_convert_ctx = sws_getContext(WIDTH, HEIGHT, AV_PIX_FMT_YUV420P, WIDTH, HEIGHT,
c->pix_fmt, sws_flags, NULL, NULL, NULL);
if(img_convert_ctx == NULL)
{
std::cout << "Cannot initialize the conversion context" << std::endl;
std::cin.get();exit(1);
}
}
fill_yuv_image(tmp_picture, frame_count, WIDTH, HEIGHT);
sws_scale(img_convert_ctx, tmp_picture->data, tmp_picture->linesize, 0, HEIGHT,
picture->data, picture->linesize);
}
else
{
fill_yuv_image(picture, frame_count, WIDTH, HEIGHT);
}
}
if (oc->oformat->flags & AVFMT_RAWPICTURE)
{
/* raw video case. The API will change slightly in the near
futur for that */
AVPacket pkt;
av_init_packet(&pkt);
pkt.flags |= AV_PKT_FLAG_KEY;
pkt.stream_index= st->index;
pkt.data= (uint8_t *)picture;
pkt.size= sizeof(AVPicture);
ret = av_interleaved_write_frame(oc, &pkt);
}
else
{
/* encode the image */
out_size = avcodec_encode_video(c, video_outbuf, video_outbuf_size, picture);
/* if zero size, it means the image was buffered */
if (out_size > 0)
{
AVPacket pkt;
av_init_packet(&pkt);
if (c->coded_frame->pts != AV_NOPTS_VALUE)
pkt.pts= av_rescale_q(c->coded_frame->pts, c->time_base, st->time_base);
if(c->coded_frame->key_frame)
pkt.flags |= AV_PKT_FLAG_KEY;
pkt.stream_index= st->index;
pkt.data= video_outbuf;
pkt.size= out_size;
/* write the compressed frame in the media file */
ret = av_interleaved_write_frame(oc, &pkt);
} else {
ret = 0;
}
}
if (ret != 0) {
std::cout << "Error while writing video frames" << std::endl;
std::cin.get();exit(1);
}
frame_count++;
}
int main ( int argc, char *argv[] )
{
const char* filename = "test.h264";
AVOutputFormat *outputFormat;
AVFormatContext *context;
AVCodecContext *codec;
AVStream *videoStream;
double videoPTS;
// init libavcodec, register all codecs and formats
av_register_all();
// auto detect the output format from the name
outputFormat = av_guess_format(NULL, filename, NULL);
if(!outputFormat)
{
std::cout << "Cannot guess output format! Using mpeg!" << std::endl;
std::cin.get();
outputFormat = av_guess_format(NULL, "h263" , NULL);
}
if(!outputFormat)
{
std::cout << "Could not find suitable output format." << std::endl;
std::cin.get();exit(1);
}
context = avformat_alloc_context();
if(!context)
{
std::cout << "Cannot allocate avformat memory." << std::endl;
std::cin.get();exit(1);
}
context->oformat = outputFormat;
sprintf_s(context->filename, sizeof(context->filename), "%s", filename);
std::cout << "Is '" << context->filename << "' = '" << filename << "'" << std::endl;
videoStream = NULL;
outputFormat->audio_codec = AV_CODEC_ID_NONE;
videoStream = addVideoStream(context, outputFormat->video_codec);
/* still needed?
if(av_set_parameters(context, NULL) < 0)
{
std::cout << "Invalid output format parameters." << std::endl;
exit(0);
}*/
av_dump_format(context, 0, filename, 1);
if(videoStream)
openVideo(context, videoStream);
if(!outputFormat->flags & AVFMT_NOFILE)
{
if(avio_open(&context->pb, filename, AVIO_FLAG_READ_WRITE) < 0)
{
std::cout << "Could not open " << filename << std::endl;
std::cin.get();exit(1);
}
}
avformat_write_header(context, 0);
while(true)
{
if(videoStream)
videoPTS = (double) videoStream->pts.val * videoStream->time_base.num / videoStream->time_base.den;
else
videoPTS = 0.;
if((!videoStream || videoPTS >= STREAM_DURATION))
{
break;
}
write_video_frame(context, videoStream);
}
av_write_trailer(context);
if(videoStream)
closeVideo(context, videoStream);
for(int i = 0; i < context->nb_streams; i++)
{
av_freep(&context->streams[i]->codec);
av_freep(&context->streams[i]);
}
if(!(outputFormat->flags & AVFMT_NOFILE))
{
avio_close(context->pb);
}
av_free(context);
std::cin.get();
return 0;
}
</string></iostream>Compile :
g++ -I ./FFmpeg/ video.cpp -L fflibs -lavcodec -lavformatThe code comes with two errors :
video.cpp:249:84: error: ‘avcodec_encode_video’ was not declared in this scope
out_size = avcodec_encode_video(c, video_outbuf, video_outbuf_size, picture);
^
video.cpp: In function ‘int main(int, char**)’:
video.cpp:342:46: error: ‘AVStream {aka struct AVStream}’ has no member named ‘pts’
videoPTS = (double) videoStream->pts.val * videoStream->time_base.num / videoStream->time_base.den;
^and a huge number of warnings for deprecation.
video.cpp: In function ‘void closeVideo(AVFormatContext*, AVStream*)’:
video.cpp:60:23: warning: ‘AVStream::codec’ is deprecated [-Wdeprecated-declarations]
avcodec_close(st->codec);
^
In file included from video.cpp:9:0:
./FFmpeg/libavformat/avformat.h:876:21: note: declared here
AVCodecContext *codec;
^
video.cpp:60:23: warning: ‘AVStream::codec’ is deprecated [-Wdeprecated-declarations]
avcodec_close(st->codec);
^
In file included from video.cpp:9:0:
./FFmpeg/libavformat/avformat.h:876:21: note: declared here
AVCodecContext *codec;
^
video.cpp:60:23: warning: ‘AVStream::codec’ is deprecated [-Wdeprecated-declarations]
avcodec_close(st->codec);
^
In file included from video.cpp:9:0:
./FFmpeg/libavformat/avformat.h:876:21: note: declared here
AVCodecContext *codec;
^
video.cpp: In function ‘AVFrame* alloc_picture(AVPixelFormat, int, int)’:
video.cpp:80:12: warning: ‘int avpicture_get_size(AVPixelFormat, int, int)’ is deprecated [-Wdeprecated-declarations]
size = avpicture_get_size(pix_fmt, width, height);
^
In file included from video.cpp:8:0:
./FFmpeg/libavcodec/avcodec.h:5228:5: note: declared here
int avpicture_get_size(enum AVPixelFormat pix_fmt, int width, int height);
^
video.cpp:80:12: warning: ‘int avpicture_get_size(AVPixelFormat, int, int)’ is deprecated [-Wdeprecated-declarations]
size = avpicture_get_size(pix_fmt, width, height);
^
In file included from video.cpp:8:0:
./FFmpeg/libavcodec/avcodec.h:5228:5: note: declared here
int avpicture_get_size(enum AVPixelFormat pix_fmt, int width, int height);
^
video.cpp:80:53: warning: ‘int avpicture_get_size(AVPixelFormat, int, int)’ is deprecated [-Wdeprecated-declarations]
size = avpicture_get_size(pix_fmt, width, height);
^
In file included from video.cpp:8:0:
./FFmpeg/libavcodec/avcodec.h:5228:5: note: declared here
int avpicture_get_size(enum AVPixelFormat pix_fmt, int width, int height);
^
video.cpp:87:5: warning: ‘int avpicture_fill(AVPicture*, const uint8_t*, AVPixelFormat, int, int)’ is deprecated [-Wdeprecated-declarations]
avpicture_fill((AVPicture *) picture, picture_buf, pix_fmt, WIDTH, HEIGHT);
^
In file included from video.cpp:8:0:
./FFmpeg/libavcodec/avcodec.h:5213:5: note: declared here
int avpicture_fill(AVPicture *picture, const uint8_t *ptr,
^
video.cpp:87:5: warning: ‘int avpicture_fill(AVPicture*, const uint8_t*, AVPixelFormat, int, int)’ is deprecated [-Wdeprecated-declarations]
avpicture_fill((AVPicture *) picture, picture_buf, pix_fmt, WIDTH, HEIGHT);
^
In file included from video.cpp:8:0:
./FFmpeg/libavcodec/avcodec.h:5213:5: note: declared here
int avpicture_fill(AVPicture *picture, const uint8_t *ptr,
^
video.cpp:87:78: warning: ‘int avpicture_fill(AVPicture*, const uint8_t*, AVPixelFormat, int, int)’ is deprecated [-Wdeprecated-declarations]
avpicture_fill((AVPicture *) picture, picture_buf, pix_fmt, WIDTH, HEIGHT);
^
In file included from video.cpp:8:0:
./FFmpeg/libavcodec/avcodec.h:5213:5: note: declared here
int avpicture_fill(AVPicture *picture, const uint8_t *ptr,
^
video.cpp: In function ‘void openVideo(AVFormatContext*, AVStream*)’:
video.cpp:96:13: warning: ‘AVStream::codec’ is deprecated [-Wdeprecated-declarations]
c = st->codec;
^
In file included from video.cpp:9:0:
./FFmpeg/libavformat/avformat.h:876:21: note: declared here
AVCodecContext *codec;
^
video.cpp:96:13: warning: ‘AVStream::codec’ is deprecated [-Wdeprecated-declarations]
c = st->codec;
^
In file included from video.cpp:9:0:
./FFmpeg/libavformat/avformat.h:876:21: note: declared here
AVCodecContext *codec;
^
video.cpp:96:13: warning: ‘AVStream::codec’ is deprecated [-Wdeprecated-declarations]
c = st->codec;
^
In file included from video.cpp:9:0:
./FFmpeg/libavformat/avformat.h:876:21: note: declared here
AVCodecContext *codec;
^
video.cpp: In function ‘AVStream* addVideoStream(AVFormatContext*, AVCodecID)’:
video.cpp:151:21: warning: ‘AVStream::codec’ is deprecated [-Wdeprecated-declarations]
codec = stream->codec;
^
In file included from video.cpp:9:0:
./FFmpeg/libavformat/avformat.h:876:21: note: declared here
AVCodecContext *codec;
^
video.cpp:151:21: warning: ‘AVStream::codec’ is deprecated [-Wdeprecated-declarations]
codec = stream->codec;
^
In file included from video.cpp:9:0:
./FFmpeg/libavformat/avformat.h:876:21: note: declared here
AVCodecContext *codec;
^
video.cpp:151:21: warning: ‘AVStream::codec’ is deprecated [-Wdeprecated-declarations]
codec = stream->codec;
^
In file included from video.cpp:9:0:
./FFmpeg/libavformat/avformat.h:876:21: note: declared here
AVCodecContext *codec;
^
video.cpp: In function ‘void write_video_frame(AVFormatContext*, AVStream*)’:
video.cpp:202:13: warning: ‘AVStream::codec’ is deprecated [-Wdeprecated-declarations]
c = st->codec;
^
In file included from video.cpp:9:0:
./FFmpeg/libavformat/avformat.h:876:21: note: declared here
AVCodecContext *codec;
^
video.cpp:202:13: warning: ‘AVStream::codec’ is deprecated [-Wdeprecated-declarations]
c = st->codec;
^
In file included from video.cpp:9:0:
./FFmpeg/libavformat/avformat.h:876:21: note: declared here
AVCodecContext *codec;
^
video.cpp:202:13: warning: ‘AVStream::codec’ is deprecated [-Wdeprecated-declarations]
c = st->codec;
^
In file included from video.cpp:9:0:
./FFmpeg/libavformat/avformat.h:876:21: note: declared here
AVCodecContext *codec;
^
video.cpp:256:20: warning: ‘AVCodecContext::coded_frame’ is deprecated [-Wdeprecated-declarations]
if (c->coded_frame->pts != AV_NOPTS_VALUE)
^
In file included from video.cpp:8:0:
./FFmpeg/libavcodec/avcodec.h:2723:35: note: declared here
attribute_deprecated AVFrame *coded_frame;
^
video.cpp:256:20: warning: ‘AVCodecContext::coded_frame’ is deprecated [-Wdeprecated-declarations]
if (c->coded_frame->pts != AV_NOPTS_VALUE)
^
In file included from video.cpp:8:0:
./FFmpeg/libavcodec/avcodec.h:2723:35: note: declared here
attribute_deprecated AVFrame *coded_frame;
^
video.cpp:256:20: warning: ‘AVCodecContext::coded_frame’ is deprecated [-Wdeprecated-declarations]
if (c->coded_frame->pts != AV_NOPTS_VALUE)
^
In file included from video.cpp:8:0:
./FFmpeg/libavcodec/avcodec.h:2723:35: note: declared here
attribute_deprecated AVFrame *coded_frame;
^
video.cpp:257:42: warning: ‘AVCodecContext::coded_frame’ is deprecated [-Wdeprecated-declarations]
pkt.pts= av_rescale_q(c->coded_frame->pts, c->time_base, st->time_base);
^
In file included from video.cpp:8:0:
./FFmpeg/libavcodec/avcodec.h:2723:35: note: declared here
attribute_deprecated AVFrame *coded_frame;
^
video.cpp:257:42: warning: ‘AVCodecContext::coded_frame’ is deprecated [-Wdeprecated-declarations]
pkt.pts= av_rescale_q(c->coded_frame->pts, c->time_base, st->time_base);
^
In file included from video.cpp:8:0:
./FFmpeg/libavcodec/avcodec.h:2723:35: note: declared here
attribute_deprecated AVFrame *coded_frame;
^
video.cpp:257:42: warning: ‘AVCodecContext::coded_frame’ is deprecated [-Wdeprecated-declarations]
pkt.pts= av_rescale_q(c->coded_frame->pts, c->time_base, st->time_base);
^
In file included from video.cpp:8:0:
./FFmpeg/libavcodec/avcodec.h:2723:35: note: declared here
attribute_deprecated AVFrame *coded_frame;
^
video.cpp:258:19: warning: ‘AVCodecContext::coded_frame’ is deprecated [-Wdeprecated-declarations]
if(c->coded_frame->key_frame)
^
In file included from video.cpp:8:0:
./FFmpeg/libavcodec/avcodec.h:2723:35: note: declared here
attribute_deprecated AVFrame *coded_frame;
^
video.cpp:258:19: warning: ‘AVCodecContext::coded_frame’ is deprecated [-Wdeprecated-declarations]
if(c->coded_frame->key_frame)
^
In file included from video.cpp:8:0:
./FFmpeg/libavcodec/avcodec.h:2723:35: note: declared here
attribute_deprecated AVFrame *coded_frame;
^
video.cpp:258:19: warning: ‘AVCodecContext::coded_frame’ is deprecated [-Wdeprecated-declarations]
if(c->coded_frame->key_frame)
^
In file included from video.cpp:8:0:
./FFmpeg/libavcodec/avcodec.h:2723:35: note: declared here
attribute_deprecated AVFrame *coded_frame;
^
video.cpp:357:40: warning: ‘AVStream::codec’ is deprecated [-Wdeprecated-declarations]
av_freep(&context->streams[i]->codec);
^
In file included from video.cpp:9:0:
./FFmpeg/libavformat/avformat.h:876:21: note: declared here
AVCodecContext *codec;
^
video.cpp:357:40: warning: ‘AVStream::codec’ is deprecated [-Wdeprecated-declarations]
av_freep(&context->streams[i]->codec);
^
In file included from video.cpp:9:0:
./FFmpeg/libavformat/avformat.h:876:21: note: declared here
AVCodecContext *codec;
^
video.cpp:357:40: warning: ‘AVStream::codec’ is deprecated [-Wdeprecated-declarations]
av_freep(&context->streams[i]->codec);
^
In file included from video.cpp:9:0:
./FFmpeg/libavformat/avformat.h:876:21: note: declared here
AVCodecContext *codec;
^
video.cpp:337:38: warning: ignoring return value of ‘int avformat_write_header(AVFormatContext*, AVDictionary**)’, declared with attribute warn_unused_result [-Wunused-result]
avformat_write_header(context, 0);
^I have also defined a few macros to redefine those who have been omited. In a modern
ffmpegAPI, they must be replaced.Could someone please help me solving errors and deprecation warnings to comply with recent
ffmpegAPI ? -
Bitmap images to WEBM video encoding
21 novembre 2013, par AnkushI am trying to encode bitmap images to webm video,but generated video is not playable
Here is code I am using,code works fine for H624.
While encoding console windows shows : [libvpx @ 009b2f60] v1.2.0
there is no webm string in produced video file. Any clue ? ( I am newbie for FFMPEG API )void create_from_bmp()
{
CFile file[5];
BYTE *szTxt[5];
int nWidth = 0;
int nHeight= 0;
int nDataLen=0;
int nLen;
CString csFileName;
for (int fileI = 1; fileI <= 5; fileI ++)
{
csFileName.Format("e:\\pics\\%d.bmp",fileI);
file[fileI - 1].Open(csFileName,CFile::modeRead | CFile::typeBinary);
nLen = file[fileI - 1].GetLength();
szTxt[fileI -1] = new BYTE[nLen];
file[fileI - 1].Read(szTxt[fileI - 1], nLen);
file[fileI - 1].Close();
//BMP bmi;//BITMAPINFO bmi;
//int nHeadLen = sizeof(BMP);
BITMAPFILEHEADER bmpFHeader;
BITMAPINFOHEADER bmpIHeader;
memcpy(&bmpFHeader,szTxt[fileI -1],sizeof(BITMAPFILEHEADER));
int nHeadLen = bmpFHeader.bfOffBits - sizeof(BITMAPFILEHEADER);
memcpy(&bmpIHeader,szTxt[fileI - 1]+sizeof(BITMAPFILEHEADER),nHeadLen);
nWidth = bmpIHeader.biWidth;// 464;// bmi.bmpInfo.bmiHeader.biWidth;// ;
nHeight = bmpIHeader.biHeight;//362;// bmi.bmpInfo.bmiHeader.biHeight;// ;
szTxt[fileI - 1] += bmpFHeader.bfOffBits;
nDataLen = nLen-bmpFHeader.bfOffBits;
}
av_register_all();
avcodec_register_all();
AVFrame *m_pRGBFrame = new AVFrame[1]; //RGB
AVFrame *m_pYUVFrame = new AVFrame[1];; //YUV
AVCodecContext *c= NULL;
AVCodecContext *in_c= NULL;
AVCodec *pCodecH264;
uint8_t * yuv_buff;//
pCodecH264 = avcodec_find_encoder(CODEC_ID_VP8);
if(!pCodecH264)
{
fprintf(stderr, "h264 codec not found\n");
exit(1);
}
c= avcodec_alloc_context3(pCodecH264);
c->bit_rate = 3000000;// put sample parameters
c->width =nWidth;//
c->height = nHeight;//
// frames per second
AVRational rate;
rate.num = 1;
rate.den = 5; //5 frames per sec
c->time_base= rate;//(AVRational){1,25};
c->gop_size = 10; // emit one intra frame every ten frames //emit one iframe per sec
c->max_b_frames=0; //
c->thread_count = 1;
c->pix_fmt = PIX_FMT_YUV420P;//PIX_FMT_RGB24;
c->codec_id=CODEC_ID_VP8;
//av_opt_set(c->priv_data, /*"preset"*/"libvpx-1080p.ffpreset", /*"slow"*/NULL, 0);
if(avcodec_open2(c,pCodecH264,NULL)<0)
printf("Cant open codec");
int size = c->width * c->height;
yuv_buff = (uint8_t *) malloc((size * 3) / 2); // size for YUV 420
uint8_t * rgb_buff = new uint8_t[nDataLen];
int outbuf_size=400000;
uint8_t * outbuf= (uint8_t*)malloc(outbuf_size);
int u_size = 0;
FILE *f=NULL;
char * filename = "e:\\pics\\myData.h264";
f = fopen(filename, "wb");
if (!f)
{
printf( "could not open %s\n", filename);
exit(1);
}
//SwsContext
SwsContext * scxt = sws_getContext(c->width,c->height,PIX_FMT_BGR24,c->width,c->height,PIX_FMT_YUV420P,SWS_POINT,NULL,NULL,NULL);
AVPacket avpkt;
//AVFrame *pTFrame=new AVFrame
for (int i=0;i<60;++i)
{
//AVFrame *m_pYUVFrame = new AVFrame[1];
int index = (i / 5) % 5;
memcpy(rgb_buff,szTxt[index],nDataLen);
avpicture_fill((AVPicture*)m_pRGBFrame, (uint8_t*)rgb_buff, PIX_FMT_RGB24, nWidth, nHeight);
avpicture_fill((AVPicture*)m_pYUVFrame, (uint8_t*)yuv_buff, PIX_FMT_YUV420P, nWidth, nHeight);
m_pRGBFrame->data[0] += m_pRGBFrame->linesize[0] * (nHeight - 1);
m_pRGBFrame->linesize[0] *= -1;
m_pRGBFrame->data[1] += m_pRGBFrame->linesize[1] * (nHeight / 2 - 1);
m_pRGBFrame->linesize[1] *= -1;
m_pRGBFrame->data[2] += m_pRGBFrame->linesize[2] * (nHeight / 2 - 1);
m_pRGBFrame->linesize[2] *= -1;
sws_scale(scxt,m_pRGBFrame->data,m_pRGBFrame->linesize,0,c->height,m_pYUVFrame->data,m_pYUVFrame->linesize);
int got_packet_ptr = 0;
av_init_packet(&avpkt);
avpkt.data = outbuf;
avpkt.size = outbuf_size;
u_size = avcodec_encode_video2(c, &avpkt, m_pYUVFrame, &got_packet_ptr);
if (u_size == 0)
{
fwrite(avpkt.data, 1, avpkt.size, f);
}
}
fclose(f);
delete []m_pRGBFrame;
delete []m_pYUVFrame;
delete []rgb_buff;
free(outbuf);
avcodec_close(c);
av_free(c);
}I want to use this code to record screen by encoding screenshots. what fps,gop size or other parameters i can use to reduce size of video.
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