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Submit bugs and patches
13 avril 2011Unfortunately a software is never perfect.
If you think you have found a bug, report it using our ticket system. Please to help us to fix it by providing the following information : the browser you are using, including the exact version as precise an explanation as possible of the problem if possible, the steps taken resulting in the problem a link to the site / page in question
If you think you have solved the bug, fill in a ticket and attach to it a corrective patch.
You may also (...) -
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 -
Publier sur MédiaSpip
13 juin 2013Puis-je poster des contenus à partir d’une tablette Ipad ?
Oui, si votre Médiaspip installé est à la version 0.2 ou supérieure. Contacter au besoin l’administrateur de votre MédiaSpip pour le savoir
Sur d’autres sites (14585)
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ffmpeg : save separate frames as still gifs
7 novembre 2013, par Eugene MThe question is simple : I don't want ffmpeg to create an animated GIF from given video stream, I want separate frames, each in GIF format. But when I set output file to something like
frame%09d.gifffmpeg tends to create an animation (and stores it exactly asframe%09d.gif). The same for-f gifoption.Of course, I could save PNGs and use ImageMagic's
convertutility to transform them to GIFs, but I don't want any additional invocation overhead because I'm dealing with live streams and going to crunch large amounts of data.Here is what I do, nothing special :
ffmpeg -i http://brightcove03-f.akamaihd.net/valgbodmandag1378107345_1_300k@80362 -f gif -y frame_%09d.gif
ffmpeg version N-54643-g15cee5e Copyright (c) 2000-2013 the FFmpeg developers
built on Jul 11 2013 03:35:11 with gcc 4.7.3 (GCC)
configuration: --enable-gpl --enable-version3 --disable-w32threads --enable-avisynth --enable-bzlib --enable-fontconfig --enable-frei0r --enable-gnu
tls --enable-iconv --enable-libass --enable-libbluray --enable-libcaca --enable-libfreetype --enable-libgsm --enable-libilbc --enable-libmodplug --ena
ble-libmp3lame --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libopenjpeg --enable-libopus --enable-librtmp --enable-libschroedinger -
-enable-libsoxr --enable-libspeex --enable-libtheora --enable-libtwolame --enable-libvo-aacenc --enable-libvo-amrwbenc --enable-libvorbis --enable-lib
vpx --enable-libx264 --enable-libxavs --enable-libxvid --enable-zlib
libavutil 52. 39.100 / 52. 39.100
libavcodec 55. 18.102 / 55. 18.102
libavformat 55. 12.101 / 55. 12.101
libavdevice 55. 3.100 / 55. 3.100
libavfilter 3. 80.100 / 3. 80.100
libswscale 2. 3.100 / 2. 3.100
libswresample 0. 17.102 / 0. 17.102
libpostproc 52. 3.100 / 52. 3.100
[flv @ 00000000002cb700] Stream discovered after head already parsed
Input #0, flv, from 'http://brightcove03-f.akamaihd.net/valgbodmandag1378107345_1_300k@80362':
Metadata:
encoder : Lavf54.6.100
Duration: 00:00:00.00, start: 0.000000, bitrate: N/A
Stream #0:0: Video: h264 (Constrained Baseline), yuv420p, 480x270 [SAR 1:1 DAR 16:9], 25 tbr, 1k tbn, 50 tbc
Stream #0:1: Audio: aac, 44100 Hz, stereo, fltp, 128 kb/s
Stream #0:2: Data: none
[swscaler @ 0000000004d051e0] No accelerated colorspace conversion found from yuv420p to bgr8.
Output #0, gif, to 'frame_%09d.gif':
Metadata:
encoder : Lavf55.12.101
Stream #0:0: Video: gif, bgr8, 480x270 [SAR 1:1 DAR 16:9], q=2-31, 200 kb/s, 100 tbn, 25 tbc
Stream mapping:
Stream #0:0 -> #0:0 (h264 -> gif)
Press [q] to stop, [?] for help
frame= 141 fps=130 q=-1.0 Lsize= 4960kB time=00:00:05.68 bitrate=7153.1kbits/s
video:5100kB audio:0kB subtitle:0 global headers:0kB muxing overhead -2.743247%After all I get a file named "frame_%03d.gif", but instead I want to have several files "frame_001.gif", "frame_002.gif", etc.
Any ideas ?
Thanks in advance. -
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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x86/vp9lpf : save a few mov in flat8in/hev masks calc.
5 février 2014, par Clément Bœsch
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