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Rennes Emotion Map 2010-11
19 octobre 2011, par
Mis à jour : Juillet 2013
Langue : français
Type : Texte
Autres articles (51)
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Personnaliser les catégories
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On peut modifier ce formulaire dans la partie :
Administration > Configuration des masques de formulaire.
Dans le cas d’un document de type média, les champs non affichés par défaut sont : Descriptif rapide
Par ailleurs, c’est dans cette partie configuration qu’on peut indiquer le (...) -
HTML5 audio and video support
13 avril 2011, parMediaSPIP uses HTML5 video and audio tags to play multimedia files, taking advantage of the latest W3C innovations supported by modern browsers.
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Sur d’autres sites (8019)
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Streaming H.264 over UDP using FFmpeg, and "dimensions not set" error
3 septembre 2015, par Baris DemirayI’m trying to stream H.264 over UDP with no luck so far. Here is a minimal code that you can reproduce the problem.
To compile,
g++ -o test -lavcodec -lavformat -lavutil test.cppExtra information, I start
ffplayas follows. Currently it’s of no use.ffplay -i udp://127.0.0.1:8554/live.sdpOutput of my code (see
avio_open()call),[libx264 @ 0x6a26c0] using mv_range_thread = 24
[libx264 @ 0x6a26c0] using cpu capabilities: MMX2 SSE2Fast SSSE3 SSE4.1 Cache64
[libx264 @ 0x6a26c0] profile High, level 3.1
Output #0, h264, to 'udp://127.0.0.1:8554/live.sdp':
Stream #0:0, 0, 0/0: Video: h264 (libx264), -1 reference frame, none, q=-1--1
[h264 @ 0x6a2020] dimensions not set
Cannot write header to stream: SuccessAnd the code,
extern "C" {
#include <libavcodec></libavcodec>avcodec.h>
#include <libavformat></libavformat>avformat.h>
#include <libavutil></libavutil>avutil.h>
}
#include <iostream>
using namespace std;
int main() {
AVCodecContext* m_codecContext;
AVCodec* m_codec;
AVFormatContext* m_formatContext;
AVStream* m_stream;
unsigned m_outWidth = 768;
unsigned m_outHeight = 608;
av_register_all();
avcodec_register_all();
avformat_network_init();
int errorStatus = 0;
char errorLog[128] = { 0 };
av_log_set_level(AV_LOG_TRACE);
string m_output("udp://127.0.0.1:8554/live.sdp");
if (avformat_alloc_output_context2(&m_formatContext, NULL, "h264", m_output.c_str()) < 0) {
cerr << "Cannot allocate output context: "
<< av_make_error_string(errorLog, 128, errorStatus) << endl;
return -1;
}
AVOutputFormat *m_outputFormat = m_formatContext->oformat;
m_codec = avcodec_find_encoder(AV_CODEC_ID_H264);
if (!m_codec) {
cerr << "Cannot find an encoder: "
<< av_make_error_string(errorLog, 128, errorStatus) << endl;
return -1;
}
m_codecContext = avcodec_alloc_context3(m_codec);
if (!m_codecContext) {
cerr << "Cannot allocate a codec context: "
<< av_make_error_string(errorLog, 128, errorStatus) << endl;
return -1;
}
m_codecContext->pix_fmt = AV_PIX_FMT_YUV420P;
m_codecContext->width = m_outWidth;
m_codecContext->height = m_outHeight;
if (avcodec_open2(m_codecContext, m_codec, NULL) < 0) {
cerr << "Cannot open codec: "
<< av_make_error_string(errorLog, 128, errorStatus) << endl;
return -1;
}
m_stream = avformat_new_stream(m_formatContext, m_codec);
if (!m_stream) {
cerr << "Cannot create a new stream: "
<< av_make_error_string(errorLog, 128, errorStatus) << endl;
return -1;
}
av_dump_format(m_formatContext, 0, m_output.c_str(), 1);
if ((errorStatus = avio_open(&m_formatContext->pb, m_output.c_str(), AVIO_FLAG_WRITE)) < 0) {
cerr << "Cannot open output: "
<< av_make_error_string(errorLog, 128, errorStatus) << endl;
return -1;
}
if (avformat_write_header(m_formatContext, NULL) < 0) {
cerr << "Cannot write header to stream: "
<< av_make_error_string(errorLog, 128, errorStatus) << endl;
return -1;
}
cout << "All done." << endl;
return 0;
}
</iostream>For those who has even more time to spare on my problem, when I change
m_outputtortsp://127.0.0.1:8554/live.sdp, andffplaycommand toffplay -rtsp_flags listen -i rtsp://127.0.0.1:8554/live.sdpI get the error,[libx264 @ 0x1e056c0] using mv_range_thread = 24
[libx264 @ 0x1e056c0] using cpu capabilities: MMX2 SSE2Fast SSSE3 SSE4.1 Cache64
[libx264 @ 0x1e056c0] profile High, level 3.1
Output #0, h264, to 'rtsp://127.0.0.1:8554/live.sdp':
Stream #0:0, 0, 0/0: Video: h264 (libx264), -1 reference frame, none, q=-1--1
Cannot open output: Protocol not foundAm I naive to expect that streaming protocol will be changed like this ?
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How to modify the bit_rate of AVFormatContext ?
27 mars 2023, par Zion LiuHello，I would like to know how to modify the bit_rate of AVFormatContext.


Here is the minimal reproducible example.This is a simple process for pushing rtmp video streams.Now I want to control the bitrate of the video it pushes.


I tried modifying the bitrate like this, but it didn't work.


AVFormatContext *ifmt_ctx = NULL, *ofmt_ctx = NULL;
int64_t bit_rate = 400*1000;
....
ofmt_ctx->bit_rate = bit_rate;


Can be compiled by
g++ -Wall -o -g -I/usr/include/glib-2.0 -I/usr/lib/x86_64-linux-gnu/glib-2.0/include -I/usr/local/include -L/usr/local/lib simplt_push_streaming.cpp -o test.out -lavformat -lavcodec -lavutil -lgobject-2.0 -lglib-2.0 -lpthread

And my ffmpeg version :
ffmpeg version 4.4.2-0ubuntu0.22.04.1

#include 
extern "C"
{
#include <libavformat></libavformat>avformat.h>
#include <libavutil></libavutil>mathematics.h>
#include <libavutil></libavutil>time.h>
};

int main(int argc, char* argv[])
{
 AVOutputFormat *ofmt = NULL;
 //Input AVFormatContext and Output AVFormatContext
 AVFormatContext *ifmt_ctx = NULL, *ofmt_ctx = NULL;
 AVPacket pkt;
 const char *in_filename, *out_filename;
 int ret, i;
 int videoindex=-1;
 int frame_index=0;
 int64_t start_time=0;
 int64_t bit_rate = 400*1000;
 in_filename = "/home/zion/video/mecha.flv";// Input file URL
 out_filename = "rtmp://localhost:1935/live/test";//Output URL [RTMP]
 av_register_all();
 avformat_network_init();
 avformat_open_input(&ifmt_ctx, in_filename, 0, 0);
 avformat_find_stream_info(ifmt_ctx, 0);
 for(i=0; inb_streams; i++) 
 if(ifmt_ctx->streams[i]->codec->codec_type==AVMEDIA_TYPE_VIDEO){
 videoindex=i;
 break;
 }
 //Output
 avformat_alloc_output_context2(&ofmt_ctx, NULL, "flv", out_filename); //RTMP
 ofmt = ofmt_ctx->oformat;
 for (i = 0; i < ifmt_ctx->nb_streams; i++) {
 //Create output AVStream according to input AVStream
 AVStream *in_stream = ifmt_ctx->streams[i];
 AVStream *out_stream = avformat_new_stream(ofmt_ctx, in_stream->codec->codec);
 //Copy the settings of AVCodecContext
 ret = avcodec_copy_context(out_stream->codec, in_stream->codec);
 out_stream->codec->codec_tag = 0;
 if (ofmt_ctx->oformat->flags & AVFMT_GLOBALHEADER)
 out_stream->codec->flags |= AV_CODEC_FLAG_GLOBAL_HEADER;
 }
 //Open output URL
 if (!(ofmt->flags & AVFMT_NOFILE)) {
 ret = avio_open(&ofmt_ctx->pb, out_filename, AVIO_FLAG_WRITE);
 }
 //Write file header
 avformat_write_header(ofmt_ctx, NULL);
 start_time=av_gettime();
 while (1) {
 AVStream *in_stream, *out_stream;
 //Get an AVPacket
 ret = av_read_frame(ifmt_ctx, &pkt);
 if (ret < 0)
 break;
 //Important:Delay
 if(pkt.stream_index==videoindex){
 AVRational time_base=ifmt_ctx->streams[videoindex]->time_base;
 AVRational time_base_q={1,AV_TIME_BASE};
 int64_t pts_time = av_rescale_q(pkt.dts, time_base, time_base_q);
 int64_t now_time = av_gettime() - start_time;
 if (pts_time > now_time)
 av_usleep(pts_time - now_time);
 }
 in_stream = ifmt_ctx->streams[pkt.stream_index];
 out_stream = ofmt_ctx->streams[pkt.stream_index];
 if(pkt.stream_index==videoindex){
 printf("Send %8d video frames to output URL\n",frame_index);
 frame_index++;
 }
/*I tried modifying the bitrate here and I'm not sure if this is the correct usage.*/
 ofmt_ctx->bit_rate = bit_rate;
 av_interleaved_write_frame(ofmt_ctx, &pkt);
 av_free_packet(&pkt);
 }
 //Write file trailer
 av_write_trailer(ofmt_ctx);
end:
 avformat_close_input(&ifmt_ctx);
 /* close output */
 if (ofmt_ctx && !(ofmt->flags & AVFMT_NOFILE))
 avio_close(ofmt_ctx->pb);
 avformat_free_context(ofmt_ctx);
 return 0;
}


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ERROR "Application provided invalid, non monotonically increasing dts to muxer in stream 1 : 6874 >= 6874" while writing encoded output to an mp4 file
11 mai 2023, par lokit khemkaI have a running RTSP stream, streaming video on a loop using the following FFMPEG command :


ffmpeg -re -stream_loop -1 -i ./ffmpeg_c_test/small_bunny_1080p_60fps.mp4 -ac 2 -f rtsp -rtsp_transport tcp rtsp://localhost:8554/mystream


The video file is obtained from the github link : https://github.com/leandromoreira/ffmpeg-libav-tutorial


I keep getting error response, when I calling the function
av_interleaved_write_framecalled from the functionremuxin the attached program. The output format ismp4, output video codec isav1and output audio codec is same as input audio codec. The error is from audio stream.

I tried to create a "minimal reproducible code", however, I think it is still not completely minimal, but it reproduces the exact error.


#include <libavcodec></libavcodec>avcodec.h>
#include <libavformat></libavformat>avformat.h>
#include <libavutil></libavutil>timestamp.h>
#include <libavutil></libavutil>opt.h>
#include <libswscale></libswscale>swscale.h>
#include 
#include 
#include 

#include 
#include 

typedef struct StreamingContext{
 AVFormatContext* avfc;
 const AVCodec *video_avc;
 const AVCodec *audio_avc;
 AVStream *video_avs;
 AVStream *audio_avs;
 AVCodecContext *video_avcc;
 AVCodecContext *audio_avcc;
 int video_index;
 int audio_index;
 char* filename;
 struct SwsContext *sws_ctx;
}StreamingContext;


typedef struct StreamingParams{
 char copy_video;
 char copy_audio;
 char *output_extension;
 char *muxer_opt_key;
 char *muxer_opt_value;
 char *video_codec;
 char *audio_codec;
 char *codec_priv_key;
 char *codec_priv_value;
}StreamingParams;

void logging(const char *fmt, ...)
{
 va_list args;
 fprintf(stderr, "LOG: ");
 va_start(args, fmt);
 vfprintf(stderr, fmt, args);
 va_end(args);
 fprintf(stderr, "\n");
}

int fill_stream_info(AVStream *avs, const AVCodec **avc, AVCodecContext **avcc)
{
 *avc = avcodec_find_decoder(avs->codecpar->codec_id);
 *avcc = avcodec_alloc_context3(*avc);
 if (avcodec_parameters_to_context(*avcc, avs->codecpar) < 0)
 {
 logging("Failed to fill Codec Context.");
 return -1;
 }
 avcodec_open2(*avcc, *avc, NULL);
 return 0;
}

int open_media(const char *in_filename, AVFormatContext **avfc)
{
 *avfc = avformat_alloc_context();
 if (avformat_open_input(avfc, in_filename, NULL, NULL) != 0)
 {
 logging("Failed to open input file %s", in_filename);
 return -1;
 }

 if (avformat_find_stream_info(*avfc, NULL) < 0)
 {
 logging("Failed to get Stream Info.");
 return -1;
 }
}

int prepare_decoder(StreamingContext *sc)
{
 for (int i = 0; i < (int)sc->avfc->nb_streams; i++)
 {
 if (sc->avfc->streams[i]->codecpar->codec_type == AVMEDIA_TYPE_VIDEO)
 {
 sc->video_avs = sc->avfc->streams[i];
 sc->video_index = i;

 if (fill_stream_info(sc->video_avs, &sc->video_avc, &sc->video_avcc))
 {
 return -1;
 }
 }
 else if (sc->avfc->streams[i]->codecpar->codec_type == AVMEDIA_TYPE_AUDIO)
 {
 sc->audio_avs = sc->avfc->streams[i];
 sc->audio_index = i;

 if (fill_stream_info(sc->audio_avs, &sc->audio_avc, &sc->audio_avcc))
 {
 return -1;
 }
 }
 else
 {
 logging("Skipping Streams other than Audio and Video.");
 }
 }
 return 0;
}

int prepare_video_encoder(StreamingContext *encoder_sc, AVCodecContext *decoder_ctx, AVRational input_framerate,
 StreamingParams sp, int scaled_frame_width, int scaled_frame_height)
{
 encoder_sc->video_avs = avformat_new_stream(encoder_sc->avfc, NULL);
 encoder_sc->video_avc = avcodec_find_encoder_by_name(sp.video_codec);
 if (!encoder_sc->video_avc)
 {
 logging("Cannot find the Codec.");
 return -1;
 }

 encoder_sc->video_avcc = avcodec_alloc_context3(encoder_sc->video_avc);
 if (!encoder_sc->video_avcc)
 {
 logging("Could not allocate memory for Codec Context.");
 return -1;
 }

 av_opt_set(encoder_sc->video_avcc->priv_data, "preset", "fast", 0);
 if (sp.codec_priv_key && sp.codec_priv_value)
 av_opt_set(encoder_sc->video_avcc->priv_data, sp.codec_priv_key, sp.codec_priv_value, 0);

 encoder_sc->video_avcc->height = scaled_frame_height;
 encoder_sc->video_avcc->width = scaled_frame_width;
 encoder_sc->video_avcc->sample_aspect_ratio = decoder_ctx->sample_aspect_ratio;

 if (encoder_sc->video_avc->pix_fmts)
 encoder_sc->video_avcc->pix_fmt = encoder_sc->video_avc->pix_fmts[0];
 else
 encoder_sc->video_avcc->pix_fmt = decoder_ctx->pix_fmt;

 encoder_sc->video_avcc->bit_rate = 2 * 1000 * 1000;

 encoder_sc->video_avcc->time_base = av_inv_q(input_framerate);
 encoder_sc->video_avs->time_base = encoder_sc->video_avcc->time_base;

 

 if (avcodec_open2(encoder_sc->video_avcc, encoder_sc->video_avc, NULL) < 0)
 {
 logging("Could not open the Codec.");
 return -1;
 }
 avcodec_parameters_from_context(encoder_sc->video_avs->codecpar, encoder_sc->video_avcc);
 return 0;
}


int prepare_copy(AVFormatContext *avfc, AVStream **avs, AVCodecParameters *decoder_par)
{
 *avs = avformat_new_stream(avfc, NULL);
 avcodec_parameters_copy((*avs)->codecpar, decoder_par);
 return 0;
}

int encode_video(StreamingContext *decoder, StreamingContext *encoder, AVFrame *input_frame)
{
 if (input_frame)
 input_frame->pict_type = AV_PICTURE_TYPE_NONE;

 AVPacket *output_packet = av_packet_alloc();


 int response = avcodec_send_frame(encoder->video_avcc, input_frame);

 while (response >= 0)
 {
 response = avcodec_receive_packet(encoder->video_avcc, output_packet);
 if (response == AVERROR(EAGAIN) || response == AVERROR_EOF)
 {
 break;
 }

 output_packet->stream_index = decoder->video_index;
 output_packet->duration = encoder->video_avs->time_base.den / encoder->video_avs->time_base.num;

 av_packet_rescale_ts(output_packet, decoder->video_avs->time_base, encoder->video_avs->time_base);
 response = av_interleaved_write_frame(encoder->avfc, output_packet);
 }

 av_packet_unref(output_packet);
 av_packet_free(&output_packet);

 return 0;
}

int remux(AVPacket **pkt, AVFormatContext **avfc, AVRational decoder_tb, AVRational encoder_tb)
{
 (*pkt)->duration = av_rescale_q((*pkt)->duration, decoder_tb, encoder_tb);
 (*pkt)->pos = -1;
 av_packet_rescale_ts(*pkt, decoder_tb, encoder_tb);
 if (av_interleaved_write_frame(*avfc, *pkt) < 0)
 {
 logging("Error while copying Stream Packet.");
 return -1;
 }
 return 0;
}

int transcode_video(StreamingContext *decoder, StreamingContext *encoder, AVPacket *input_packet, AVFrame *input_frame)
{
 int response = avcodec_send_packet(decoder->video_avcc, input_packet);
 while (response >= 0)
 {
 response = avcodec_receive_frame(decoder->video_avcc, input_frame);
 
 if (response == AVERROR(EAGAIN) || response == AVERROR_EOF)
 {
 break;
 }
 if (response >= 0)
 {
 if (encode_video(decoder, encoder, input_frame))
 return -1;
 }

 av_frame_unref(input_frame);
 }
 return 0;
}

int main(int argc, char *argv[])
{
 const int scaled_frame_width = 854;
 const int scaled_frame_height = 480;
 StreamingParams sp = {0};
 sp.copy_audio = 1;
 sp.copy_video = 0;
 sp.video_codec = "libsvtav1";
 
 StreamingContext *decoder = (StreamingContext *)calloc(1, sizeof(StreamingContext));
 decoder->filename = "rtsp://localhost:8554/mystream";

 StreamingContext *encoder = (StreamingContext *)calloc(1, sizeof(StreamingContext));
 encoder->filename = "small_bunny_9.mp4";
 
 if (sp.output_extension)
 {
 strcat(encoder->filename, sp.output_extension);
 }

 open_media(decoder->filename, &decoder->avfc);
 prepare_decoder(decoder);


 avformat_alloc_output_context2(&encoder->avfc, NULL, "mp4", encoder->filename);
 AVRational input_framerate = av_guess_frame_rate(decoder->avfc, decoder->video_avs, NULL);
 prepare_video_encoder(encoder, decoder->video_avcc, input_framerate, sp, scaled_frame_width, scaled_frame_height);

 prepare_copy(encoder->avfc, &encoder->audio_avs, decoder->audio_avs->codecpar);
 

 if (encoder->avfc->oformat->flags & AVFMT_GLOBALHEADER)
 encoder->avfc->flags |= AV_CODEC_FLAG_GLOBAL_HEADER;

 if (!(encoder->avfc->oformat->flags & AVFMT_NOFILE))
 {
 if (avio_open(&encoder->avfc->pb, encoder->filename, AVIO_FLAG_WRITE) < 0)
 {
 logging("could not open the output file");
 return -1;
 }
 }

 
 if (avformat_write_header(encoder->avfc, NULL) < 0)
 {
 logging("an error occurred when opening output file");
 return -1;
 }

 AVFrame *input_frame = av_frame_alloc();
 AVPacket *input_packet = av_packet_alloc();

 while (1)
 {
 int ret = av_read_frame(decoder->avfc, input_packet);
 if(ret<0)
 break;
 if (decoder->avfc->streams[input_packet->stream_index]->codecpar->codec_type == AVMEDIA_TYPE_VIDEO)
 {
 if (transcode_video(decoder, encoder, input_packet, input_frame))
 return -1;
 av_packet_unref(input_packet);

 }
 else if (decoder->avfc->streams[input_packet->stream_index]->codecpar->codec_type == AVMEDIA_TYPE_AUDIO)
 {
 
 if (remux(&input_packet, &encoder->avfc, decoder->audio_avs->time_base, encoder->audio_avs->time_base))
 return -1;
 }
 else
 {
 logging("Ignoring all nonvideo or audio packets.");
 }
 }

 if (encode_video(decoder, encoder, NULL))
 return -1;
 

 av_write_trailer(encoder->avfc);


 if (input_frame != NULL)
 {
 av_frame_free(&input_frame);
 input_frame = NULL;
 }

 if (input_packet != NULL)
 {
 av_packet_free(&input_packet);
 input_packet = NULL;
 }

 avformat_close_input(&decoder->avfc);

 avformat_free_context(decoder->avfc);
 decoder->avfc = NULL;
 avformat_free_context(encoder->avfc);
 encoder->avfc = NULL;

 avcodec_free_context(&decoder->video_avcc);
 decoder->video_avcc = NULL;
 avcodec_free_context(&decoder->audio_avcc);
 decoder->audio_avcc = NULL;

 free(decoder);
 decoder = NULL;
 free(encoder);
 encoder = NULL;

 return 0;
}



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