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  • MediaSPIP v0.2

    21 juin 2013, par

    MediaSPIP 0.2 est la première version de MediaSPIP stable.
    Sa date de sortie officielle est le 21 juin 2013 et est annoncée ici.
    Le fichier zip ici présent contient uniquement les sources de MediaSPIP en version standalone.
    Comme pour la version précédente, il est nécessaire d’installer manuellement l’ensemble des dépendances logicielles sur le serveur.
    Si vous souhaitez utiliser cette archive pour une installation en mode ferme, il vous faudra également procéder à d’autres modifications (...)

  • Les tâches Cron régulières de la ferme

    1er décembre 2010, par

    La gestion de la ferme passe par l’exécution à intervalle régulier de plusieurs tâches répétitives dites Cron.
    Le super Cron (gestion_mutu_super_cron)
    Cette tâche, planifiée chaque minute, a pour simple effet d’appeler le Cron de l’ensemble des instances de la mutualisation régulièrement. Couplée avec un Cron système sur le site central de la mutualisation, cela permet de simplement générer des visites régulières sur les différents sites et éviter que les tâches des sites peu visités soient trop (...)

  • Mise à disposition des fichiers

    14 avril 2011, par

    Par défaut, lors de son initialisation, MediaSPIP ne permet pas aux visiteurs de télécharger les fichiers qu’ils soient originaux ou le résultat de leur transformation ou encodage. Il permet uniquement de les visualiser.
    Cependant, il est possible et facile d’autoriser les visiteurs à avoir accès à ces documents et ce sous différentes formes.
    Tout cela se passe dans la page de configuration du squelette. Il vous faut aller dans l’espace d’administration du canal, et choisir dans la navigation (...)

Sur d’autres sites (9091)

  • Unable to encode single frame h264 (.mp4) video with FFmpeg. No video stream present

    1er avril 2021, par Maxito

    I have achieved this with ffmpeg command line tool using the command. The folder had only one image.

    



    


    ffmpeg -r 24 -i image%03d.bmp -c:v libx264 -pix_fmt yuv420p
 oneframex.mp4

    


    



    I would like to do the same with C++. If I encode a video of three or more frames, video encodes correctly, but the result of encoding a one or two frames video never has a video stream, as reported by ffprobe and some media players.

    



    Comparing with ffprobe, my video (the one with three or more frames) and the one generated by the command tool show almost the same information. Only bitrate and encoder version are different.

    



    I have tried adding force_key_frames to 1, tried with many encoding options and have be unsuccessful.

    



    The application output gives me this information :

    



    


    [libx264 @ 20d1b840] using cpu capabilities : MMX2 SSE2Fast SSSE3
 SSE4.2 AVX

    
 


    [libx264 @ 20d1b840] profile High, level 4.0

    
 


    [libx264 @ 20d1b840] 264 - core 142 r2431 ac76440 - H.264/MPEG-4 AVC
 codec - Copyleft 2003-2014 - http://www.videolan.org/x264.html -
 options : cabac=0 ref=1 deblock=1:0:0 analyse=0x3:0x113 me=dia subme=8
 psy=1 psy_rd=1.00:0.00 mixed_ref=0 me_range=16 chroma_me=0 trellis=0
 8x8dct=1 cqm=0 deadzone=21,11 fast_pskip=1 chroma_qp_offset=-2
 threads=1 lookahead_threads=1 sliced_threads=0 nr=0 decimate=1
 interlaced=0 bluray_compat=0 constrained_intra=0 bframes=0 weightp=0
 keyint=1 keyint_min=1 scenecut=0 intra_refresh=0 rc=crf mbtree=0
 crf=10.0 qcomp=0.60 qpmin=0 qpmax=25 qpstep=4 ip_ratio=1.40 aq=1:1.00

    


    



    These are my main parameters :

    



    pCodecCtx->codec_id = AV_CODEC_ID_H264;
pCodecCtx->pix_fmt= AV_PIX_FMT_YUV420P; 
pCodecCtx->gop_size = 1;
pCodecCtx->bit_rate = 400000;
pCodecCtx->me_range = 16;
pCodecCtx->max_qdiff = 4;
pCodecCtx->qcompress = 0.6;
pCodecCtx->qmin = 0;
pCodecCtx->qmax = 25;
pCodecCtx->time_base.den = 24;
pCodecCtx->time_base.num = 1;

AVDictionary *param = 0;
            av_dict_set(&param, "preset", "slow", 0);
            av_dict_set(&param, "profile", "high", 0);
            av_dict_set(&param, "crf", "10", 0); //this gave me quality
            av_dict_set(&param, "force_key_frames", "1", 0);


    



    In my encoding I just added

    



    ppicture->pts = pCodecCtx->frame_number


    



    to avoid non-strictly-monotonic PTS message. And tried the methods from this question in case it had something to do.

    



    I’m sure I must be missing some important parameter to be able to create such a small video. I will take any suggestion.

    


  • Algorithm when recording SegmentTimeline of MPEG-DASH MPD in shaka packager

    25 mars 2021, par jgkim0518

    I packaged a media stream by mpeg-dash transcoded video at twice the speed and audio at normal speed.
Here is the command :

    


    ffmpeg -re -stream_loop -1 -i timing_logic.mp4 -c:v hevc_nvenc -filter:v "setpts=2*PTS" -c:a libfdk_aac -map 0:v -map 0:a -f mpegts udp://xxx.xxx.xxx.xxx:xxxx?pkt_size=1316


    


    The source information used here is as follows :

    


    Input #0, mpegts, from '/home/test/timing_logic/timing_logic.mp4':
Duration: 00:00:30.22, start: 1.400000, bitrate: 16171 kb/s
Program 1
Metadata:
service_name : Service01
service_provider: FFmpeg
Stream #0:0[0x100]: Video: hevc (Main 10) (HEVC / 0x43564548), yuv420p10le(tv, bt709), 3840x2160 [SAR 1:1 DAR 16:9], 50 fps, 50 tbr, 90k tbn, 50 tbc
Stream #0:1[0x101](eng): Audio: mp2 ([3][0][0][0] / 0x0003), 48000 Hz, stereo, fltp, 128 kb/s Stream mapping:
Stream #0:0 -> #0:0 (hevc (native) -> hevc (hevc_nvenc))
Stream #0:1 -> #0:1 (mp2 (native) -> aac (libfdk_aac))
Press [q] to stop, [?] for help
frame= 0 fps=0.0 q=0.0 size= 0kB time=-577014:32:22.77 bitrate= -0.0kbits/s speed=N/A
frame= 0 fps=0.0 q=0.0 size= 0kB time=-577014:32:22.77 bitrate= -0.0kbits/s speed=N/A
Output #0, mpegts, to 'udp://xxx.xxx.xxx.xxx:xxxx?pkt_size=1316':
Metadata:
encoder : Lavf58.45.100
Stream #0:0: Video: hevc (hevc_nvenc) (Main 10), p010le, 3840x2160 [SAR 1:1 DAR 16:9], q=-1--1, 2000 kb/s, 50 fps, 90k tbn, 50 tbc
Metadata:
encoder : Lavc58.91.100 hevc_nvenc
Side data:
cpb: bitrate max/min/avg: 0/0/2000000 buffer size: 4000000 vbv_delay: N/A
Stream #0:1(eng): Audio: aac (libfdk_aac), 48000 Hz, stereo, s16, 139 kb/s
Metadata:
encoder : Lavc58.91.100 libfdk_aac


    


    My shaka packager command is :

    


    packager \ 'in=udp://xxx.xxx.xxx.xxx:xxxx,stream=video,init_segment=/home/test/timing_logic/package/video/0/video.mp4,segment_template=/home/test/timing_logic/package/video/0/$Time$.m4s' \
'in=udp://xxx.xxx.xxx.xxx:xxxx,stream=audio,init_segment=/home/test/timing_logic/package/audio/0/audio.mp4,segment_template=/home/test/timing_logic/package/audio/0/$Time$.m4a' \
--segment_duration 5 --fragment_duration 5 --minimum_update_period 5 --min_buffer_time 5 \
--preserved_segments_outside_live_window 24 --time_shift_buffer_depth 40 \
--allow_codec_switching --allow_approximate_segment_timeline --log_file_generation_deletion \
--mpd_output $OUTPUT/$output_mpd.mpd &


    


    Looking at the mpd generated as a result of packaging, the duration of the audio is twice that of the video, and the number of segments is half.
The following is the content of mpd :

    


    &lt;?xml version="1.0" encoding="UTF-8"?>&#xA;&#xA;<mpd xmlns="urn:mpeg:dash:schema:mpd:2011" profiles="urn:mpeg:dash:profile:isoff-live:2011" minbuffertime="PT5S" type="dynamic" publishtime="2021-03-23T10:01:57Z" availabilitystarttime="2021-03-23T09:59:55Z" minimumupdateperiod="PT5S" timeshiftbufferdepth="PT40S">&#xA;<period start="PT0S">&#xA;<adaptationset contenttype="audio" segmentalignment="true">&#xA;<representation bandwidth="140020" codecs="mp4a.40.2" mimetype="audio/mp4" audiosamplingrate="48000">&#xA;<audiochannelconfiguration schemeiduri="urn:mpeg:dash:23003:3:audio_channel_configuration:2011" value="2"></audiochannelconfiguration>&#xA;<segmenttemplate timescale="90000" initialization="/home/test/timing_logic/package/audio/0/audio.mp4" media="/home/test/timing_logic/package/audio/0/$Time$.m4a" startnumber="16">&#xA;<segmenttimeline>&#xA;<s t="6751436" d="449280"></s>&#xA;<s t="7200716" d="451200"></s>&#xA;<s t="7651916" d="449280"></s>&#xA;<s t="8101196" d="374400"></s>&#xA;<s t="8551196" d="449280"></s>&#xA;<s t="9000476" d="451200"></s>&#xA;<s t="9451674" d="449280"></s>&#xA;<s t="9900956" d="449280"></s>&#xA;<s t="10350236" d="451200"></s>&#xA;<s t="10801434" d="374400"></s>&#xA;</segmenttimeline>&#xA;</segmenttemplate>&#xA;</representation>&#xA;</adaptationset>&#xA;<adaptationset contenttype="video" width="3840" height="2160" framerate="90000/3600" segmentalignment="true" par="16:9">&#xA;<representation bandwidth="1520392" codecs="hvc1.2.4.L153" mimetype="video/mp4" sar="1:1">&#xA;<segmenttemplate timescale="90000" initialization="/home/test/timing_logic/package/video/0/video.mp4" media="/home/test/timing_logic/package/video/0/$Time$.m4s" startnumber="19">&#xA;<segmenttimeline>&#xA;<s t="16954440" d="900000" r="4"></s>&#xA;</segmenttimeline>&#xA;</segmenttemplate>&#xA;</representation>&#xA;</adaptationset>&#xA;</period>&#xA;</mpd>&#xA;

    &#xA;

    When looking at the MPD, it seems that the shaka packager checks the PTS or DTS of the TS when creating a segment and recording the contents of the SegmentTimeline.&#xA;But I couldn't understand even by looking at the MPEG standard documentation and the DASH-IF documentation.

    &#xA;

    My question is whether the packager refers to PTS or DTS when creating a segment.&#xA;How are SegmentTimeline's S@t and S@d recorded ?&#xA;What algorithm is the SegmentTimeline recorded with ? Please help me. Thank you.

    &#xA;

  • Algorithm when recording SegmentTimeline

    24 mars 2021, par jgkim0518

    I packaged a media stream by mpeg-dash transcoded video at twice the speed and audio at normal speed.&#xA;Here is the command :

    &#xA;

    ffmpeg -re -stream_loop -1 -i timing_logic.mp4 -c:v hevc_nvenc -filter:v "setpts=2*PTS" -c:a libfdk_aac -map 0:v -map 0:a -f mpegts udp://xxx.xxx.xxx.xxx:xxxx?pkt_size=1316&#xA;

    &#xA;

    The source information used here is as follows :

    &#xA;

    Input #0, mpegts, from &#x27;/home/test/timing_logic/timing_logic.mp4&#x27;:&#xA;Duration: 00:00:30.22, start: 1.400000, bitrate: 16171 kb/s&#xA;Program 1&#xA;Metadata:&#xA;service_name : Service01&#xA;service_provider: FFmpeg&#xA;Stream #0:0[0x100]: Video: hevc (Main 10) (HEVC / 0x43564548), yuv420p10le(tv, bt709), 3840x2160 [SAR 1:1 DAR 16:9], 50 fps, 50 tbr, 90k tbn, 50 tbc&#xA;Stream #0:1[0x101](eng): Audio: mp2 ([3][0][0][0] / 0x0003), 48000 Hz, stereo, fltp, 128 kb/s Stream mapping:&#xA;Stream #0:0 -> #0:0 (hevc (native) -> hevc (hevc_nvenc))&#xA;Stream #0:1 -> #0:1 (mp2 (native) -> aac (libfdk_aac))&#xA;Press [q] to stop, [?] for help&#xA;frame= 0 fps=0.0 q=0.0 size= 0kB time=-577014:32:22.77 bitrate= -0.0kbits/s speed=N/A&#xA;frame= 0 fps=0.0 q=0.0 size= 0kB time=-577014:32:22.77 bitrate= -0.0kbits/s speed=N/A&#xA;Output #0, mpegts, to &#x27;udp://xxx.xxx.xxx.xxx:xxxx?pkt_size=1316&#x27;:&#xA;Metadata:&#xA;encoder : Lavf58.45.100&#xA;Stream #0:0: Video: hevc (hevc_nvenc) (Main 10), p010le, 3840x2160 [SAR 1:1 DAR 16:9], q=-1--1, 2000 kb/s, 50 fps, 90k tbn, 50 tbc&#xA;Metadata:&#xA;encoder : Lavc58.91.100 hevc_nvenc&#xA;Side data:&#xA;cpb: bitrate max/min/avg: 0/0/2000000 buffer size: 4000000 vbv_delay: N/A&#xA;Stream #0:1(eng): Audio: aac (libfdk_aac), 48000 Hz, stereo, s16, 139 kb/s&#xA;Metadata:&#xA;encoder : Lavc58.91.100 libfdk_aac&#xA;

    &#xA;

    My shaka packager command is :

    &#xA;

    packager \ &#x27;in=udp://xxx.xxx.xxx.xxx:xxxx,stream=video,init_segment=/home/test/timing_logic/package/video/0/video.mp4,segment_template=/home/test/timing_logic/package/video/0/$Time$.m4s&#x27; \&#xA;&#x27;in=udp://xxx.xxx.xxx.xxx:xxxx,stream=audio,init_segment=/home/test/timing_logic/package/audio/0/audio.mp4,segment_template=/home/test/timing_logic/package/audio/0/$Time$.m4a&#x27; \&#xA;--segment_duration 5 --fragment_duration 5 --minimum_update_period 5 --min_buffer_time 5 \&#xA;--preserved_segments_outside_live_window 24 --time_shift_buffer_depth 40 \&#xA;--allow_codec_switching --allow_approximate_segment_timeline --log_file_generation_deletion \&#xA;--mpd_output $OUTPUT/$output_mpd.mpd &amp;&#xA;

    &#xA;

    Looking at the mpd generated as a result of packaging, the duration of the audio is twice that of the video, and the number of segments is half.&#xA;The following is the content of mpd :

    &#xA;

    &lt;?xml version="1.0" encoding="UTF-8"?>&#xA;&#xA;<mpd xmlns="urn:mpeg:dash:schema:mpd:2011" profiles="urn:mpeg:dash:profile:isoff-live:2011" minbuffertime="PT5S" type="dynamic" publishtime="2021-03-23T10:01:57Z" availabilitystarttime="2021-03-23T09:59:55Z" minimumupdateperiod="PT5S" timeshiftbufferdepth="PT40S">&#xA;<period start="PT0S">&#xA;<adaptationset contenttype="audio" segmentalignment="true">&#xA;<representation bandwidth="140020" codecs="mp4a.40.2" mimetype="audio/mp4" audiosamplingrate="48000">&#xA;<audiochannelconfiguration schemeiduri="urn:mpeg:dash:23003:3:audio_channel_configuration:2011" value="2"></audiochannelconfiguration>&#xA;<segmenttemplate timescale="90000" initialization="/home/test/timing_logic/package/audio/0/audio.mp4" media="/home/test/timing_logic/package/audio/0/$Time$.m4a" startnumber="16">&#xA;<segmenttimeline>&#xA;<s t="6751436" d="449280"></s>&#xA;<s t="7200716" d="451200"></s>&#xA;<s t="7651916" d="449280"></s>&#xA;<s t="8101196" d="374400"></s>&#xA;<s t="8551196" d="449280"></s>&#xA;<s t="9000476" d="451200"></s>&#xA;<s t="9451674" d="449280"></s>&#xA;<s t="9900956" d="449280"></s>&#xA;<s t="10350236" d="451200"></s>&#xA;<s t="10801434" d="374400"></s>&#xA;</segmenttimeline>&#xA;</segmenttemplate>&#xA;</representation>&#xA;</adaptationset>&#xA;<adaptationset contenttype="video" width="3840" height="2160" framerate="90000/3600" segmentalignment="true" par="16:9">&#xA;<representation bandwidth="1520392" codecs="hvc1.2.4.L153" mimetype="video/mp4" sar="1:1">&#xA;<segmenttemplate timescale="90000" initialization="/home/test/timing_logic/package/video/0/video.mp4" media="/home/test/timing_logic/package/video/0/$Time$.m4s" startnumber="19">&#xA;<segmenttimeline>&#xA;<s t="16954440" d="900000" r="4"></s>&#xA;</segmenttimeline>&#xA;</segmenttemplate>&#xA;</representation>&#xA;</adaptationset>&#xA;</period>&#xA;</mpd>&#xA;

    &#xA;

    When looking at the MPD, it seems that the shaka packager checks the PTS or DTS of the TS when creating a segment and recording the contents of the SegmentTimeline.&#xA;But I couldn't understand even by looking at the MPEG standard documentation and the DASH-IF documentation.

    &#xA;

    My question is whether the packager refers to PTS or DTS when creating a segment.&#xA;How are SegmentTimeline's S@t and S@d recorded ?&#xA;What algorithm is the SegmentTimeline recorded with ? Please help me. Thank you.

    &#xA;

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