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Création définitive du canal
12 mars 2010, parLorsque votre demande est validée, vous pouvez alors procéder à la création proprement dite du canal. Chaque canal est un site à part entière placé sous votre responsabilité. Les administrateurs de la plateforme n’y ont aucun accès.
A la validation, vous recevez un email vous invitant donc à créer votre canal.
Pour ce faire il vous suffit de vous rendre à son adresse, dans notre exemple "http://votre_sous_domaine.mediaspip.net".
A ce moment là un mot de passe vous est demandé, il vous suffit d’y (...) -
Les tâches Cron régulières de la ferme
1er décembre 2010, parLa 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 (...) -
Amélioration de la version de base
13 septembre 2013Jolie sélection multiple
Le plugin Chosen permet d’améliorer l’ergonomie des champs de sélection multiple. Voir les deux images suivantes pour comparer.
Il suffit pour cela d’activer le plugin Chosen (Configuration générale du site > Gestion des plugins), puis de configurer le plugin (Les squelettes > Chosen) en activant l’utilisation de Chosen dans le site public et en spécifiant les éléments de formulaires à améliorer, par exemple select[multiple] pour les listes à sélection multiple (...)
Sur d’autres sites (4403)
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FFMPEG H264 with custom overlay per frame
4 octobre 2020, par La bla blaWe have a stream that is stored in the cloud (Amazon S3) as individual H264 frames. The frames are stored as
framexxxxxx.264
, the numbering doesn't start from 0 but rather from some larger number, say 1000 (so,frame001000.264
)

The goal is to create a mp4 clip which is either timelapse or just faster for inspection and other checking (much faster, compressing around 3 hours of video down to < 20 minutes), this also requires we overlay the frame number (the filename) on the frame itself


At first I was creating a timelapse by pulling from S3 only the keyframes (i-frames ? still rather new to codecs & stuff) and overlaying the filename on them and saving as png (which probably isn't needed, but that's what I did) using (this command is used inside a python script)


ffmpeg -y -i {h264_name} -vf \"scale=1920:-1, 
drawtext=fontfile=/usr/share/fonts/truetype/ubuntu-font-family/Ubuntu-B.ttf:fontsize=34:text={txt}:fontcolor=white:x=50:y=50:bordercolor=black:borderw=2\" 
-c:a copy -pix_fmt yuv420p {basename}.png



after this I combined all the frames by using python to convert the lowest numbered frame to
0.png
and incrementing (so it would be continuous, because I only used keyframes the numbers originally weren't sequential) and running

ffmpeg -y -f image2 -i %d.png -r {self.params.fps} -vcodec libx264 -crf {self.params.crf} -pix_fmt yuv420p {out_file}



and this worked great, but the difference between keyframes was too long to allow for proper inspection


so now for the question(s)


since I know frames that are not keyframes (p-frames ?) can't be used alone by ffmpeg, the method of overlaying the file name and converting it to png (or keep as h264, same thing) won't work, or at least, I couldn't find a way for it to work, maybe there's a way to specify a frame's keyframe ?, how can one overlay the filename (and not the frame number as shown here for example)


Also, is it possible to skip some p-frames between the keyframes ? (so if a keyframe is every 30 frames, we would take a keyframe, a frame 15 frames later, and next another keyframe)


I thought about using ffmpeg's pipe option to feed it with the files as they're being downloaded, but I'm not sure if I can specify drawtext this way


Also, if there's another alternative that can achieve that (at first I was converting to png, using python and OpenCV to add the filename and then merging the pngs to mp4, but then I found drawtext can do that in a single command so I used it)


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lavf/movenc : enable dvh1 FourCC
5 février 2023, par Damiano Galassilavf/movenc : enable dvh1 FourCC
This is required to pass through Dolby Vision metadata to x265.
Profiles 5 and 8 require the "dvh1" fourCC :
https://professional.dolby.com/siteassets/content-creation/dolby-vision-for-content-creators/dolby-vision-streams-within-the-http-live-streaming-format-v2.0-13-november-2018.pdf#unique_10
https://professional.dolby.com/siteassets/content-creation/dolby-vision-for-content-creators/dolbyvisioninmpegdashspecification_v2_0_public_20190107.pdf#unique_13
https://professional.dolby.com/siteassets/content-creation/dolby-vision-for-content-creators/dolby_vision_bitstreams_within_the_iso_base_media_file_format_dec2017.pdfSee also https://github.com/HandBrake/HandBrake/pull/4838 for more
details. -
Concat two mp4 files with MP4Box error : Bad Parameter [on hold]
6 février 2014, par user3279646I'm trying to concat two mp4 files. But I get an error : Bad Parameter
Can someone help me with this problem ?
I'm using de debian packages. On a previously version it worked fine. I moved from a old debian version to the new one and I also had to change the ffmpeg to avconv which I use to create these mp4 files. I also had to change the audio codec to '-acodec aac -strict experimental'
Kind Regards,
MarcelMP4Box -force-cat -cat conv1-1391608417314.mp4 -add conv1-1391608417345.mp4 -new output.mp4
IsoMedia import - track ID 1 - Video (size 384 x 288)
Error importing conv1-1391608417345.mp4: Bad ParameterMP4Box -info conv1-1391608417314.mp4
Movie Info
Timescale 1000 - Duration 00:00:23.985
Fragmented File no - 2 track(s)
File Brand isom - version 512
Created: UNKNOWN DATE
File has root IOD (9 bytes)
Scene PL 0xff - Graphics PL 0xff - OD PL 0xff
Visual PL: Not part of MPEG-4 Visual profiles (0xfe)
Audio PL: Not part of MPEG-4 audio profiles (0xfe)
No streams included in root OD
iTunes Info:
Encoder Software: Lavf53.21.1
Track # 1 Info - TrackID 1 - TimeScale 1000 - Duration 00:00:23.985
Media Info: Language "Undetermined" - Type "vide:avc1" - 23988 samples
Visual Track layout: x=0 y=0 width=384 height=288
MPEG-4 Config: Visual Stream - ObjectTypeIndication 0x21
AVC/H264 Video - Visual Size 384 x 288
AVC Info: 1 SPS - 1 PPS - Profile High @ Level 4.2
NAL Unit length bits: 32
Self-synchronized
Track # 2 Info - TrackID 2 - TimeScale 44100 - Duration 00:00:23.962
Media Info: Language "Undetermined" - Type "soun:mp4a" - 1032 samples
MPEG-4 Config: Audio Stream - ObjectTypeIndication 0x40
MPEG-4 Audio MPEG-4 Audio AAC LC - 2 Channel(s) - SampleRate 44100
Synchronized on stream 1
Alternate Group ID 1MP4Box -version
MP4Box - GPAC version 0.5.0-rev
GPAC Copyright: (c) Jean Le Feuvre 2000-2005
(c) ENST 2005-200X
GPAC Configuration: --build=x86_64-linux-gnu --prefix=/usr --includedir=${prefix}/include --mandir=${prefix}/share/man --infodir=${prefix}/share/info --sysconfdir=/etc --localstatedir=/var --libdir=${prefix}/lib/x86_64-linux-gnu --libexecdir=${prefix}/lib/x86_64-linux-gnu --disable-maintainer-mode --disable-dependency-tracking --prefix=/usr --mandir=${prefix}/share/man --libdir=lib/x86_64-linux-gnu --extra-cflags='-Wall -fPIC -DPIC -I/usr/include/mozjs -DXP_UNIX' --enable-joystick --enable-debug --disable-ssl
Features: GPAC_HAS_JPEG GPAC_HAS_PNG