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Exemple de boutons d’action pour une collection collaborative
27 février 2013, par
Mis à jour : Mars 2013
Langue : français
Type : Image
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Exemple de boutons d’action pour une collection personnelle
27 février 2013, par
Mis à jour : Février 2013
Langue : English
Type : Image
Autres articles (54)
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Les autorisations surchargées par les plugins
27 avril 2010, parMediaspip core
autoriser_auteur_modifier() afin que les visiteurs soient capables de modifier leurs informations sur la page d’auteurs -
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.
The MediaSPIP player used has been created specifically for MediaSPIP and can be easily adapted to fit in with a specific theme.
For older browsers the Flowplayer flash fallback is used.
MediaSPIP allows for media playback on major mobile platforms with the above (...) -
Support audio et vidéo HTML5
10 avril 2011MediaSPIP utilise les balises HTML5 video et audio pour la lecture de documents multimedia en profitant des dernières innovations du W3C supportées par les navigateurs modernes.
Pour les navigateurs plus anciens, le lecteur flash Flowplayer est utilisé.
Le lecteur HTML5 utilisé a été spécifiquement créé pour MediaSPIP : il est complètement modifiable graphiquement pour correspondre à un thème choisi.
Ces technologies permettent de distribuer vidéo et son à la fois sur des ordinateurs conventionnels (...)
Sur d’autres sites (8636)
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How to save the video stream as h264
16 mars 2023, par aaadddzxcI pull the stream through ffmpeg, and then save the video of this stream as an h264 file, but the saved file cannot be played. Why is this ?


The h264 saved by the following code cannot be played,i dont know why...


i try to vlc play, but cant play the h264 file.


can be save to h264 without avformat_alloc_output_context2 function ?


#include <thread>
#include <iostream>
#include <fstream>
extern "C"
{
#include <libavcodec></libavcodec>avcodec.h>
#include <libavcodec></libavcodec>bsf.h>
#include <libavformat></libavformat>avformat.h>
}

#pragma comment(lib,"avcodec.lib")
#pragma comment(lib,"avdevice.lib")
#pragma comment(lib,"avfilter.lib")
#pragma comment(lib,"avformat.lib")
#pragma comment(lib,"avutil.lib")
#pragma comment(lib,"swresample.lib")
#pragma comment(lib,"swscale.lib")

int mp4toannexb(AVBSFContext* bsf_ctx, AVPacket* pkt, std::ofstream& out)
{
 int ret;

 ret = av_bsf_send_packet(bsf_ctx, pkt);
 if (ret < 0) {
 std::cout << "bsf send packet failed, errno:" << ret << std::endl;
 return -1;
 }

 for (;;) {
 ret = av_bsf_receive_packet(bsf_ctx, pkt);
 if (AVERROR_EOF == ret || AVERROR(EAGAIN) == ret) {
 return 0;
 }
 if (ret < 0) {
 std::cout << "Could not receive packet, errno:" << ret << std::endl;
 return -1;
 }
 out.write((const char*)pkt->data, pkt->size);
 }
 return 0;
}


int main()
{
 AVOutputFormat* ofmt = NULL;
 AVFormatContext* ifmt_ctx = NULL;
 AVBSFContext* bsf_ctx = NULL;
 AVPacket* pkt = NULL;
 const char* in_filename = "http://192.168.1.12:8088/live/123.flv";
 int ret = -1;
 int video_index = -1;
 std::ofstream outh264("D:\\ConsoleApplication1\\Debug\\out.h264", std::ios::binary | std::ios::trunc);

 avformat_network_init();

 if ((ifmt_ctx = avformat_alloc_context()) == NULL) {
 std::cout << "avformat_alloc_context failed." << std::endl;
 exit(1);
 }

 if ((ret = avformat_open_input(&ifmt_ctx, in_filename, 0, 0)) < 0) {
 std::cout << "Could not open input file." << std::endl;
 exit(1);
 }

 if ((ret = avformat_find_stream_info(ifmt_ctx, 0)) < 0) {
 std::cout << "Failed to retrieve input stream information" << std::endl;
 return -1;
 }

 if (!(pkt = av_packet_alloc())) {
 std::cout << "Could not allocate packet" << std::endl;
 return -1;
 }

 video_index = av_find_best_stream(ifmt_ctx, AVMEDIA_TYPE_VIDEO, -1, -1, NULL, 0);
 if (video_index < 0) {
 std::cout << "Could not find stream " << std::string(av_get_media_type_string(AVMEDIA_TYPE_VIDEO)) << std::endl;
 return -1;
 }

 av_dump_format(ifmt_ctx, 0, in_filename, 0);

 const AVBitStreamFilter* filter = av_bsf_get_by_name("h264_mp4toannexb");
 if (NULL == filter) {
 std::cout << "Could not create filter" << std::endl;
 return -1;
 }

 ret = av_bsf_alloc(filter, &bsf_ctx);
 if (ret < 0) {
 printf("Could not alloc bitstream filter \n");
 return -1;
 }

 // avcodec_parameters_from_context
 ret = avcodec_parameters_copy(bsf_ctx->par_in, ifmt_ctx->streams[video_index]->codecpar);
 if (ret < 0) {
 printf("Parameter copy filed, errno: %d \n", ret);
 return -1;
 }

 ret = av_bsf_init(bsf_ctx);
 if (ret < 0) {
 printf("BSF init failed, errno: %d \n", ret);
 return -1;
 }

 while (av_read_frame(ifmt_ctx, pkt) >= 0) {
 if (pkt->stream_index == video_index)
 {
 mp4toannexb(bsf_ctx, pkt, outh264);
 }
 av_packet_unref(pkt);
 }
 outh264.close();
 avformat_close_input(&ifmt_ctx);
 av_packet_free(&pkt);
 av_bsf_free(&bsf_ctx);

 return 0;
}
</fstream></iostream></thread>

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FFProbe generated data don't seem to agree with calculated data using ffmpeg libraries
18 janvier 2020, par ark1974Using ffmpeg library avformat I am trying to check if the ffprobe generated data agrees with the data generated by the library. The code objective is to try to seek to the nearest key frame. When trying to seek at 100 frame or less, the codes returns 0 all the time.
When trying to seek at 200 frame, the codes returns 4 all the time. But the result ie 4th frame don’t seem to be right. Where am I wrong ? Is my time_base conversion to actual frame faulty ?The test result using ffprobe
Filename = test.mp4
Duration = 00:00:10.56
Fps = 25
Total frames = 256
The key frames pkt_pts_time are at 2.120000 and 0.000000 (using -skip_frame nokey )
Corresponding pkt_duration_time: 0.040000 and 0.040000 ( same, why?)Abstract of the code :
// Objective: seek to the nearest key frame
frameIndex = 200;
int64_t timeBase = (int64_t(pCodecCtx->time_base.num) * AV_TIME_BASE) / int64_t(pCodecCtx->time_base.den);
int64_t seekTarget = int64_t(frameIndex) * timeBase;
if (av_seek_frame(pFormatCtx, -1, seekTarget, AVSEEK_FLAG_FRAME | AVSEEK_FLAG_BACKWARD) < 0) return -1;
//convert the time_base to actual frame
auto time2frame = [&](int64_t tb) {
return tb * int64_t(pCodecCtx->time_base.den) / (int64_t(pCodecCtx->time_base.num) * AV_TIME_BASE);
};
AVPacket avPacket;
int result = av_read_frame(pFormatCtx, &avPacket);
if (result == 0) {
auto dts = avPacket.dts;
auto pts = avPacket.pts;
auto idx = avPacket.stream_index;
auto f = time2frame(pts); // expecting the actual frame here
std::cout << dts << pts << idx << f;
} -
x86/vp9lpf : save a few mov in flat8in/hev masks calc.
5 février 2014, par Clément Bœsch
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