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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 (...) -
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 (...) -
De l’upload à la vidéo finale [version standalone]
31 janvier 2010, parLe chemin d’un document audio ou vidéo dans SPIPMotion est divisé en trois étapes distinctes.
Upload et récupération d’informations de la vidéo source
Dans un premier temps, il est nécessaire de créer un article SPIP et de lui joindre le document vidéo "source".
Au moment où ce document est joint à l’article, deux actions supplémentaires au comportement normal sont exécutées : La récupération des informations techniques des flux audio et video du fichier ; La génération d’une vignette : extraction d’une (...)
Sur d’autres sites (6916)
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How to extract frames at 30 fps using FFMPEG APIs on Android ?
11 mars 2020, par Amber BeriwalWe are working on a project that consumes
FFMPEGlibrary for video frame extraction on Android platform.On Windows, we have observed :
- Using CLI, ffmpeg is capable of extracting frames at 30 fps using command
ffmpeg -i input.flv -vf fps=1 out%d.png. - Using Xuggler, we are able to extract frames at 30 fps.
- Using FFMPEG APIs directly in code, we are getting frames at 30 fps.
But when we use FFMPEG APIs directly on Android (See Hardware Details), we are getting following results :
- 720p video (1280 x 720) - 16 fps (approx. 60 ms/frame)
- 1080p video (1920 x 1080) - 7 fps (approx. 140 ms/frame)
We haven’t tested Xuggler/CLI on Android yet.
Ideally, we should be able to get the data in constant time (approx. 30 ms/frame).
How can we get 30 fps on Android ?
Code being used on Android :
if (avformat_open_input(&pFormatCtx, pcVideoFile, NULL, NULL)) {
iError = -1; //Couldn't open file
}
if (!iError) {
//Retrieve stream information
if (avformat_find_stream_info(pFormatCtx, NULL) < 0)
iError = -2; //Couldn't find stream information
}
//Find the first video stream
if (!iError) {
for (i = 0; i < pFormatCtx->nb_streams; i++) {
if (AVMEDIA_TYPE_VIDEO
== pFormatCtx->streams[i]->codec->codec_type) {
iFramesInVideo = pFormatCtx->streams[i]->nb_index_entries;
duration = pFormatCtx->streams[i]->duration;
begin = pFormatCtx->streams[i]->start_time;
time_base = (pFormatCtx->streams[i]->time_base.num * 1.0f)
/ pFormatCtx->streams[i]->time_base.den;
pCodecCtx = avcodec_alloc_context3(NULL);
if (!pCodecCtx) {
iError = -6;
break;
}
AVCodecParameters params = { 0 };
iReturn = avcodec_parameters_from_context(&params,
pFormatCtx->streams[i]->codec);
if (iReturn < 0) {
iError = -7;
break;
}
iReturn = avcodec_parameters_to_context(pCodecCtx, &params);
if (iReturn < 0) {
iError = -7;
break;
}
//pCodecCtx = pFormatCtx->streams[i]->codec;
iVideoStreamIndex = i;
break;
}
}
}
if (!iError) {
if (iVideoStreamIndex == -1) {
iError = -3; // Didn't find a video stream
}
}
if (!iError) {
// Find the decoder for the video stream
pCodec = avcodec_find_decoder(pCodecCtx->codec_id);
if (pCodec == NULL) {
iError = -4;
}
}
if (!iError) {
// Open codec
if (avcodec_open2(pCodecCtx, pCodec, NULL) < 0)
iError = -5;
}
if (!iError) {
iNumBytes = av_image_get_buffer_size(AV_PIX_FMT_RGB24, pCodecCtx->width,
pCodecCtx->height, 1);
// initialize SWS context for software scaling
sws_ctx = sws_getContext(pCodecCtx->width, pCodecCtx->height,
pCodecCtx->pix_fmt, pCodecCtx->width, pCodecCtx->height,
AV_PIX_FMT_RGB24,
SWS_BILINEAR,
NULL,
NULL,
NULL);
if (!sws_ctx) {
iError = -7;
}
}
clock_gettime(CLOCK_MONOTONIC_RAW, &end);
delta_us = (end.tv_sec - start.tv_sec) * 1000000
+ (end.tv_nsec - start.tv_nsec) / 1000;
start = end;
//LOGI("Starting_Frame_Extraction: %lld", delta_us);
if (!iError) {
while (av_read_frame(pFormatCtx, &packet) == 0) {
// Is this a packet from the video stream?
if (packet.stream_index == iVideoStreamIndex) {
pFrame = av_frame_alloc();
if (NULL == pFrame) {
iError = -8;
break;
}
// Decode video frame
avcodec_decode_video2(pCodecCtx, pFrame, &iFrameFinished,
&packet);
if (iFrameFinished) {
//OUR CODE
}
av_frame_free(&pFrame);
pFrame = NULL;
}
av_packet_unref(&packet);
}
} - Using CLI, ffmpeg is capable of extracting frames at 30 fps using command
-
How to extract frames at 30 fps using FFMPEG APIs on Android ?
8 septembre 2016, par Amber BeriwalWe are working on a project that consumes
FFMPEGlibrary for video frame extraction on Android platform.On Windows, we have observed :
- Using CLI, ffmpeg is capable of extracting frames at 30 fps using command
ffmpeg -i input.flv -vf fps=1 out%d.png. - Using Xuggler, we are able to extract frames at 30 fps.
- Using FFMPEG APIs directly in code, we are getting frames at 30 fps.
But when we use FFMPEG APIs directly on Android (See Hardware Details), we are getting following results :
- 720p video (1280 x 720) - 16 fps (approx. 60 ms/frame)
- 1080p video (1920 x 1080) - 7 fps (approx. 140 ms/frame)
We haven’t tested Xuggler/CLI on Android yet.
Ideally, we should be able to get the data in constant time (approx. 30 ms/frame).
How can we get 30 fps on Android ?
Code being used on Android :
if (avformat_open_input(&pFormatCtx, pcVideoFile, NULL, NULL)) {
iError = -1; //Couldn't open file
}
if (!iError) {
//Retrieve stream information
if (avformat_find_stream_info(pFormatCtx, NULL) < 0)
iError = -2; //Couldn't find stream information
}
//Find the first video stream
if (!iError) {
for (i = 0; i < pFormatCtx->nb_streams; i++) {
if (AVMEDIA_TYPE_VIDEO
== pFormatCtx->streams[i]->codec->codec_type) {
iFramesInVideo = pFormatCtx->streams[i]->nb_index_entries;
duration = pFormatCtx->streams[i]->duration;
begin = pFormatCtx->streams[i]->start_time;
time_base = (pFormatCtx->streams[i]->time_base.num * 1.0f)
/ pFormatCtx->streams[i]->time_base.den;
pCodecCtx = avcodec_alloc_context3(NULL);
if (!pCodecCtx) {
iError = -6;
break;
}
AVCodecParameters params = { 0 };
iReturn = avcodec_parameters_from_context(&params,
pFormatCtx->streams[i]->codec);
if (iReturn < 0) {
iError = -7;
break;
}
iReturn = avcodec_parameters_to_context(pCodecCtx, &params);
if (iReturn < 0) {
iError = -7;
break;
}
//pCodecCtx = pFormatCtx->streams[i]->codec;
iVideoStreamIndex = i;
break;
}
}
}
if (!iError) {
if (iVideoStreamIndex == -1) {
iError = -3; // Didn't find a video stream
}
}
if (!iError) {
// Find the decoder for the video stream
pCodec = avcodec_find_decoder(pCodecCtx->codec_id);
if (pCodec == NULL) {
iError = -4;
}
}
if (!iError) {
// Open codec
if (avcodec_open2(pCodecCtx, pCodec, NULL) < 0)
iError = -5;
}
if (!iError) {
iNumBytes = av_image_get_buffer_size(AV_PIX_FMT_RGB24, pCodecCtx->width,
pCodecCtx->height, 1);
// initialize SWS context for software scaling
sws_ctx = sws_getContext(pCodecCtx->width, pCodecCtx->height,
pCodecCtx->pix_fmt, pCodecCtx->width, pCodecCtx->height,
AV_PIX_FMT_RGB24,
SWS_BILINEAR,
NULL,
NULL,
NULL);
if (!sws_ctx) {
iError = -7;
}
}
clock_gettime(CLOCK_MONOTONIC_RAW, &end);
delta_us = (end.tv_sec - start.tv_sec) * 1000000
+ (end.tv_nsec - start.tv_nsec) / 1000;
start = end;
//LOGI("Starting_Frame_Extraction: %lld", delta_us);
if (!iError) {
while (av_read_frame(pFormatCtx, &packet) == 0) {
// Is this a packet from the video stream?
if (packet.stream_index == iVideoStreamIndex) {
pFrame = av_frame_alloc();
if (NULL == pFrame) {
iError = -8;
break;
}
// Decode video frame
avcodec_decode_video2(pCodecCtx, pFrame, &iFrameFinished,
&packet);
if (iFrameFinished) {
//OUR CODE
}
av_frame_free(&pFrame);
pFrame = NULL;
}
av_packet_unref(&packet);
}
} - Using CLI, ffmpeg is capable of extracting frames at 30 fps using command
-
ffmpeg crashes on crossfades between 3 clips if 2 clips coming from same input file [closed]
14 avril 2020, par ErikI observed that ffmpeg 4.2.2 (macOS) crashes in particular cases of crossfades between clips, if one clip comes from file
1.dv, and two clips are cut out of file2.dv, as shown below :


ffmpeg -f lavfi -i color=black:size=720x576:duration=11:rate=25 -i 1.dv -i 2.dv -filter_complex "\
 [1:v]trim=5:10,setpts=expr=PTS-STARTPTS,yadif,fade=alpha=1:d=2:st=3:type=out,setpts=expr=PTS-STARTPTS,fifo[s5];\
 [2:v]split=2[s7][s8];\
 [s7]trim=5:10,setpts=expr=PTS-STARTPTS,yadif,fade=alpha=1:d=2:type=in,fade=alpha=1:d=2:st=6:type=out,setpts=expr=PTS-STARTPTS+(3/TB),fifo[s15];\
 [s8]trim=12:17,setpts=expr=PTS-STARTPTS,yadif,fade=alpha=1:d=2:type=in,setpts=expr=PTS-STARTPTS+(6/TB),fifo[s22];\
 [0:v][s5]overlay=eof_action=repeat[s6];\
 [s6][s15]overlay=eof_action=repeat[s16];\
 [s16][s22]overlay=eof_action=repeat[s24];\
 [1:a]atrim=5:10,asetpts=expr=PTS-STARTPTS[s26];\
 [2:a]asplit=2[s27][s28];\
 [s27]atrim=5:10,asetpts=expr=PTS-STARTPTS[s30];\
 [s28]atrim=12:17,asetpts=expr=PTS-STARTPTS[s33];\
 [s26][s30]acrossfade=d=2[s31];\
 [s31][s33]acrossfade=d=2[s36]" \
 -map "[s24]" -map "[s36]" -ab 128k -acodec aac -crf 23 -movflags faststart -preset medium -tune film -vcodec libx264 -aspect 1024:576 out.mp4 -y



The order makes a difference : if the two clips from
2.dvare used first and then the clip from1.dvis appended, everything works fine. Also, if all clips are coming from different files.


ffmpeg 3.4.6 (ubuntu 18.04) shows no issues in any case.



A self-compiled ffmpeg version N-97322-gb1699f4 (commit 2020-04-13) works with short clips as above, but crashes if one of the two clips taken from
2.dvis getting longer. In my tests 1500 frames (64 sec) is OK, 1700 (68 sec) leads to a segmentation fault. That is, if you replace in the command line above :


- 

[s7]trim=5:10...->[s7]trim=0:68and accordingly[s27]atrim=5:10...->[s27]atrim=0:68







Interestingly, the length of the clip taken from
1.dvdoes not play a role.


The ffmpeg output shows about 20 times :



frame= 0 fps=0.0 q=0.0 size= 0kB time=00:00:00.00 bitrate=N/A speed= 0x 



before it continues (seg fault case) :



frame= 4 fps=0.3 q=0.0 size= 0kB time=00:00:00.00 bitrate=N/A speed= 0x 
frame= 24 fps=1.6 q=0.0 size= 0kB time=00:00:00.00 bitrate=N/A speed= 0x 
frame= 25 fps=1.5 q=0.0 size= 0kB time=00:00:00.00 bitrate=N/A speed= 0x 
frame= 34 fps=1.9 q=0.0 size= 0kB time=00:00:00.00 bitrate=N/A speed= 0x 
frame= 36 fps=2.0 q=0.0 size= 0kB time=00:00:00.00 bitrate=N/A speed= 0x 
frame= 39 fps=2.1 q=0.0 size= 0kB time=00:00:00.00 bitrate=N/A speed= 0x 
frame= 40 fps=2.0 q=0.0 size= 0kB time=00:00:00.00 bitrate=N/A speed= 0x 
frame= 40 fps=2.0 q=0.0 size= 0kB time=00:00:00.00 bitrate=N/A speed= 0x 
frame= 40 fps=1.9 q=0.0 size= 0kB time=00:00:00.00 bitrate=N/A speed= 0x 




success case :



frame= 5 fps=0.4 q=0.0 size= 0kB time=00:00:00.00 bitrate=N/A speed= 0x 
frame= 42 fps=3.2 q=28.0 size= 0kB time=00:00:00.00 bitrate=N/A speed= 0x 
frame= 53 fps=3.9 q=28.0 size= 0kB time=00:00:00.36 bitrate= 2.9kbits/s speed=0.0264x 
frame= 65 fps=4.6 q=28.0 size= 0kB time=00:00:00.84 bitrate= 1.2kbits/s speed=0.0594x 
... 



Slightly older versions included in the newest MacOS builds from zeranoe.com (git-2020-04-13-59e3a9a) and evermeet.cx (N-97308-g14dd0a9057-tessus, from 2020-04-12) are working nicely - also on my production cases (longer clips).



Any feedback would be appreciated !


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