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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 -
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 -
(Dés)Activation de fonctionnalités (plugins)
18 février 2011, parPour gérer l’ajout et la suppression de fonctionnalités supplémentaires (ou plugins), MediaSPIP utilise à partir de la version 0.2 SVP.
SVP permet l’activation facile de plugins depuis l’espace de configuration de MediaSPIP.
Pour y accéder, il suffit de se rendre dans l’espace de configuration puis de se rendre sur la page "Gestion des plugins".
MediaSPIP est fourni par défaut avec l’ensemble des plugins dits "compatibles", ils ont été testés et intégrés afin de fonctionner parfaitement avec chaque (...)
Sur d’autres sites (8027)
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ffmpeg DASH encoding : always getting bitrate as 200k for vp9 codec
29 novembre 2019, par SaurabhI am using following command, earlier put here : to generate DASH files :
ffmpeg -y -nostdin -loglevel error -i "$1" \
-map 0:v:0 -map 0:v:0 -map 0:v:0 -map 0:v:0 -map 0:v:0 -map 0:v:0 -map 0:a\?:0 \
-maxrate:v:0 350k -bufsize:v:0 700k -c:v:0 libx264 -filter:v:0 "scale=320:-2" \
-maxrate:v:1 1000k -bufsize:v:1 2000k -c:v:1 libx264 -filter:v:1 "scale=640:-2" \
-maxrate:v:2 3000k -bufsize:v:2 6000k -c:v:2 libx264 -filter:v:2 "scale=1280:-2" \
-maxrate:v:3 300k -minrate:v:3 100k -bufsize:v:3 600k -c:v:3 libvpx-vp9 -filter:v:3 "scale=320:-2" \
-maxrate:v:4 1088k -minrate:v:4 200k -bufsize:v:4 2176k -c:v:4 libvpx-vp9 -filter:v:4 "scale=640:-2" \
-maxrate:v:5 1500k -minrate:v:5 300k -bufsize:v:5 3000k -c:v:5 libvpx-vp9 -filter:v:5 "scale=1280:-2" \
-use_timeline 1 -use_template 1 -adaptation_sets "id=0,streams=0,1,2 id=1,streams=3,4,5 id=2,streams=a" \
-threads 8 -crf 3 -seg_duration 5 -hls_init_time 1 -hls_time 5 -hls_playlist true -f dash "$2"The issue is, in the output, I always get bandwidth as 200k for vp9 codec(see output below), while for same video bandwidth for h264 codec varies as par resolution and quite less, I expected vp9 to be even less as it compresses more. I have tested using multiple different options like :
-b:v,-deadline,-cpu-used-crf, etc, but not working expected with different values of these, What am I missing ?Sample output
mpdfile :<?xml version="1.0" encoding="utf-8"?>
<mpd xmlns="urn:mpeg:dash:schema:mpd:2011" profiles="urn:mpeg:dash:profile:isoff-live:2011" type="static" mediapresentationduration="PT25.4S" minbuffertime="PT15.0S">
<programinformation>
</programinformation>
<period start="PT0.0S">
<adaptationset contenttype="video" segmentalignment="true" bitstreamswitching="true" lang="und">
<representation mimetype="video/mp4" codecs="avc1.64000c" bandwidth="104972" width="320" height="180" framerate="24000/1001">
<segmenttemplate timescale="24000" initialization="init-stream$RepresentationID$.m4s" media="chunk-stream$RepresentationID$-$Number%05d$.m4s" startnumber="1">
<segmenttimeline>
<s t="0" d="130130"></s>
<s d="250250"></s>
<s d="176176"></s>
<s d="54054"></s>
</segmenttimeline>
</segmenttemplate>
</representation>
<representation mimetype="video/mp4" codecs="avc1.64001e" bandwidth="227233" width="640" height="360" framerate="24000/1001">
<segmenttemplate timescale="24000" initialization="init-stream$RepresentationID$.m4s" media="chunk-stream$RepresentationID$-$Number%05d$.m4s" startnumber="1">
<segmenttimeline>
<s t="0" d="130130"></s>
<s d="250250"></s>
<s d="180180"></s>
<s d="50050"></s>
</segmenttimeline>
</segmenttemplate>
</representation>
<representation mimetype="video/mp4" codecs="avc1.64001f" bandwidth="616878" width="1280" height="720" framerate="24000/1001">
<segmenttemplate timescale="24000" initialization="init-stream$RepresentationID$.m4s" media="chunk-stream$RepresentationID$-$Number%05d$.m4s" startnumber="1">
<segmenttimeline>
<s t="0" d="130130"></s>
<s d="250250"></s>
<s d="180180"></s>
<s d="50050"></s>
</segmenttimeline>
</segmenttemplate>
</representation>
</adaptationset>
<adaptationset contenttype="video" segmentalignment="true" bitstreamswitching="true" lang="und">
<representation mimetype="video/mp4" codecs="vp09.00.11.08" bandwidth="200000" width="320" height="180" framerate="24000/1001">
<segmenttemplate timescale="24000" initialization="init-stream$RepresentationID$.m4s" media="chunk-stream$RepresentationID$-$Number%05d$.m4s" startnumber="1">
<segmenttimeline>
<s t="0" d="128128" r="3"></s>
<s d="98098"></s>
</segmenttimeline>
</segmenttemplate>
</representation>
<representation mimetype="video/mp4" codecs="vp09.00.21.08" bandwidth="200000" width="640" height="360" framerate="24000/1001">
<segmenttemplate timescale="24000" initialization="init-stream$RepresentationID$.m4s" media="chunk-stream$RepresentationID$-$Number%05d$.m4s" startnumber="1">
<segmenttimeline>
<s t="0" d="128128" r="3"></s>
<s d="98098"></s>
</segmenttimeline>
</segmenttemplate>
</representation>
<representation mimetype="video/mp4" codecs="vp09.00.31.08" bandwidth="200000" width="1280" height="720" framerate="24000/1001">
<segmenttemplate timescale="24000" initialization="init-stream$RepresentationID$.m4s" media="chunk-stream$RepresentationID$-$Number%05d$.m4s" startnumber="1">
<segmenttimeline>
<s t="0" d="128128" r="3"></s>
<s d="98098"></s>
</segmenttimeline>
</segmenttemplate>
</representation>
</adaptationset>
<adaptationset contenttype="audio" segmentalignment="true" bitstreamswitching="true" lang="eng">
<representation mimetype="audio/mp4" codecs="mp4a.40.2" bandwidth="128000" audiosamplingrate="44100">
<audiochannelconfiguration schemeiduri="urn:mpeg:dash:23003:3:audio_channel_configuration:2011" value="2"></audiochannelconfiguration>
<segmenttemplate timescale="44100" initialization="init-stream$RepresentationID$.m4s" media="chunk-stream$RepresentationID$-$Number%05d$.m4s" startnumber="1">
<segmenttimeline>
<s t="0" d="235520" r="3"></s>
<s d="180224"></s>
</segmenttimeline>
</segmenttemplate>
</representation>
</adaptationset>
</period>
</mpd>I am using this video, but it is coming same for all 30 sec video I have tried.
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Algorithm when recording SegmentTimeline of MPEG-DASH MPD in shaka packager
25 mars 2021, par jgkim0518I 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 :


<?xml version="1.0" encoding="UTF-8"?>

<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">
<period start="PT0S">
<adaptationset contenttype="audio" segmentalignment="true">
<representation bandwidth="140020" codecs="mp4a.40.2" mimetype="audio/mp4" audiosamplingrate="48000">
<audiochannelconfiguration schemeiduri="urn:mpeg:dash:23003:3:audio_channel_configuration:2011" value="2"></audiochannelconfiguration>
<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">
<segmenttimeline>
<s t="6751436" d="449280"></s>
<s t="7200716" d="451200"></s>
<s t="7651916" d="449280"></s>
<s t="8101196" d="374400"></s>
<s t="8551196" d="449280"></s>
<s t="9000476" d="451200"></s>
<s t="9451674" d="449280"></s>
<s t="9900956" d="449280"></s>
<s t="10350236" d="451200"></s>
<s t="10801434" d="374400"></s>
</segmenttimeline>
</segmenttemplate>
</representation>
</adaptationset>
<adaptationset contenttype="video" width="3840" height="2160" framerate="90000/3600" segmentalignment="true" par="16:9">
<representation bandwidth="1520392" codecs="hvc1.2.4.L153" mimetype="video/mp4" sar="1:1">
<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">
<segmenttimeline>
<s t="16954440" d="900000" r="4"></s>
</segmenttimeline>
</segmenttemplate>
</representation>
</adaptationset>
</period>
</mpd>


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.
But I couldn't understand even by looking at the MPEG standard documentation and the DASH-IF documentation.


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


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APPLY Strong to Buffer rule. Quit Switching Bit rates MPEG DASH
14 juillet 2015, par VinayI am using mpeg dash for adaptive bit rate streaming of video from my server.
I have used ffmpeg and MP4Box to generate 4 different quality video files from my source .mp4
The .mpd file generated has the below code
<?xml version="1.0"?>
<mpd xmlns="urn:mpeg:dash:schema:mpd:2011" minbuffertime="PT1.500000S" type="static" mediapresentationduration="PT0H3M1.42S" profiles="urn:mpeg:dash:profile:isoff-on-demand:2011">
<programinformation moreinformationurl="http://gpac.sourceforge.net">
</programinformation>
<period duration="PT0H3M1.42S">
<adaptationset segmentalignment="true" maxwidth="1920" maxheight="1080" maxframerate="24" par="16:9" lang="und" subsegmentstartswithsap="1">
<representation mimetype="video/mp4" codecs="avc1.64000d" width="320" height="240" framerate="24" sar="1:1" startwithsap="1" bandwidth="375715">
<baseurl>400_dashinit.mp4</baseurl>
<segmentbase indexrangeexact="true" indexrange="904-1403">
<initialization range="0-903"></initialization>
</segmentbase>
</representation>
<representation mimetype="video/mp4" codecs="avc1.640015" width="420" height="270" framerate="24" sar="1:1" startwithsap="1" bandwidth="644824">
<baseurl>700_dashinit.mp4</baseurl>
<segmentbase indexrangeexact="true" indexrange="905-1404">
<initialization range="0-904"></initialization>
</segmentbase>
</representation>
<representation mimetype="video/mp4" codecs="avc1.64001f" width="1024" height="576" framerate="24" sar="1:1" startwithsap="1" bandwidth="1349484">
<baseurl>1500_dashinit.mp4</baseurl>
<segmentbase indexrangeexact="true" indexrange="905-1404">
<initialization range="0-904"></initialization>
</segmentbase>
</representation>
<representation mimetype="video/mp4" codecs="avc1.64001f" width="1280" height="720" framerate="24" sar="1:1" startwithsap="1" bandwidth="2264379">
<baseurl>2500_dashinit.mp4</baseurl>
<segmentbase indexrangeexact="true" indexrange="905-1404">
<initialization range="0-904"></initialization>
</segmentbase>
</representation>
<representation mimetype="video/mp4" codecs="avc1.640028" width="1920" height="1080" framerate="24" sar="1:1" startwithsap="1" bandwidth="3633049">
<baseurl>4000_dashinit.mp4</baseurl>
<segmentbase indexrangeexact="true" indexrange="906-1405">
<initialization range="0-905"></initialization>
</segmentbase>
</representation>
</adaptationset>
</period>
</mpd>I am using video.js along with dash.js to playback the mpeg dash content on client side. The issue is that the video doesn’t playback perfectly when i simulate network conditions from chrome dev tools.
It works at times and it doesn’t at others. For ex the stream starts with bit rate of 400kbps and then detects enough bandwidth available so it switches to 2500kbps. Then when i bring down my bandwidth to 400kbps again then the video freezes at some point of time.
At times the video freezes after few initial seconds of playback when it tries to switch the stream. I think there might be some command line parameter that i am missing while generating my video files via ffmpeg or generating .mpd file via MP4Box.
below are the commands i use for ffmpeg and MP4Box
ffmpeg -y -i inputfile -c:a libfdk_aac -ac 2 -ab 128k -c:v libx264 -r 24 – g 24 -b:v 1500k -maxrate 1500k -bufsize 1000k -vf "scale=-1:720" outputfile.mp4
MP4Box -dash [DURATION] -rap -frag-rap -profile [PROFILE] -out [path/to/outpout.file] [path/to/input1.file] [path/to/input2.file] [path/to/input3.file]Also while i am generating .mpd files via MP4Box i am getting below warning in console
[DASH]: Files have non-proportional track layouts (320x240 vs 420x270) but sample size and aspect ratio match, assuming precision issue
[DASH]: Files have non-proportional track layouts (320x240 vs 1024x576) but sample size and aspect ratio match, assuming precision issue
[DASH]: Files have non-proportional track layouts (320x240 vs 1280x720) but sample size and aspect ratio match, assuming precision issue
[DASH]: Files have non-proportional track layouts (320x240 vs 1920x1080) but sample size and aspect ratio match, assuming precision issueWhenever the video stops playing the chrome console has these logs
Number of times the buffer has run dry: 25
Apply STRONG to buffer rule.
Quit switching bit rates.I don’t have any clue as to why the buffers run dry and it stops switching the bit rates.
Anything that is predominantly wrong in the process ?
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