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Mise à disposition des fichiers
14 avril 2011, parPar 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 (...) -
MediaSPIP : Modification des droits de création d’objets et de publication définitive
11 novembre 2010, parPar défaut, MediaSPIP permet de créer 5 types d’objets.
Toujours par défaut les droits de création et de publication définitive de ces objets sont réservés aux administrateurs, mais ils sont bien entendu configurables par les webmestres.
Ces droits sont ainsi bloqués pour plusieurs raisons : parce que le fait d’autoriser à publier doit être la volonté du webmestre pas de l’ensemble de la plateforme et donc ne pas être un choix par défaut ; parce qu’avoir un compte peut servir à autre choses également, (...) -
Use, discuss, criticize
13 avril 2011, parTalk to people directly involved in MediaSPIP’s development, or to people around you who could use MediaSPIP to share, enhance or develop their creative projects.
The bigger the community, the more MediaSPIP’s potential will be explored and the faster the software will evolve.
A discussion list is available for all exchanges between users.
Sur d’autres sites (6805)
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Next pts does not match previous pts plus duration when transcoding an AAC audio with ffmpeg
17 septembre 2021, par b1subIn my understanding, the following statement must hold :


next pts = previous pts + duration


But, I got this list of
PTSes fromffprobethat looks odd to me :

<packet pts="63000" duration="2089">
<packet pts="65070" duration="2089">
<packet pts="67140" duration="2089">
<packet pts="69300" duration="2089">
<packet pts="71370" duration="2089">
<packet pts="73440" duration="2089">
<packet pts="75510" duration="2089">
<packet pts="77670" duration="2089">
</packet></packet></packet></packet></packet></packet></packet></packet>

The corresponding
PTSgaps are as follows. You can see none of the below gaps matches2089:

63000 <> 65070: 2070
65070 <> 67140: 2070
67140 <> 69300: 2160
69300 <> 71370: 2070
71370 <> 73440: 2070
73440 <> 75510: 2070
75510 <> 77670: 2160


I have no deep understanding of
AACor transcoding, so I talked with some random guy on#ffmpeg. As per what he said, the gap should be a fixed value :

20:01 -!- Icedream [~icedream@hzn-b.serverkomplex.de] has quit [Quit: A lol made me boom.]
20:02 < DeHackEd> I would expect them to increment at a constant rate, since AAC (which is probably what you're using) uses fixed size
 audio chunks. But that's very inconsistent
20:03 < DeHackEd> (+/- 1 pts number would be acceptable)


To tell you the truth, this is a problematic video, but not in a way you would expect. I'm getting intermittent audio clipping sound, if two or more audio packets are crammed into a single
PESpacket. What's special about this configuration is that, the player must guessPTSes for the trailing audio packets except the first one. Since thePTSgaps are not consistent, the player must have used wrongPTSes for the trailing ones, and this looks to me like the cause.

But, what could be the trigger ? Here are some contexts you can kindly refer to :


- 

- the original video has no surprising
PTSgap. This is the result from my custom-made script to extract all unique gaps :




$ ./foo.sh ./original.flv
diff 296448 occurs at 296448 // just a first packet (=has no previous packet)
diff 24 occurs at 296472
diff 23 occurs at 296495


- 

- this is the command I used for transcoding :




$FFMPEG -hide_banner -loglevel info -nostats \
 -i $input \
 -map "[out1]" -c:v libx264 -r 30 -force_key_frames "expr:gte(t, n_forced*$keyFrameInterval)" -preset veryfast -vprofile high -minrate 4.5M -maxrate 6M -bufsize 6M \
 -map 0:a -c:a aac -b:a:1 128K -af "aformat=sample_rates=44100|48000:channel_layouts=stereo" \
 -map 0:a -c:a aac -b:a:2 32K -af "aformat=sample_rates=44100|48000:channel_layouts=stereo" \
 -f mpegts -tune zerolatency pipe:1 > \
 >($FFMPEG -hide_banner -loglevel info -nostats \
 -i - \
 -map 0:v -c:v copy -map 0:1 -c:a copy -bsf:a aac_adtstoasc -tune zerolatency -f flv -max_muxing_queue_size 1024 ${output}_1080 \
 -map 0:v -s $(width 1280 720 $orientation)x$(height 1280 720 $orientation) -c:v libx264 -r 30 -force_key_frames "expr:gte(t, n_forced*$keyFrameInterval)" -preset veryfast -vprofile high -minrate 3M -maxrate 4M -bufsize 4M -map 0:1 -c:a copy -bsf:a aac_adtstoasc -f flv -tune zerolatency -max_muxing_queue_size 1024 ${output}_720 \
 ...


- the original video has no surprising
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Revision 790fb13215 : Use above/left (instead of previous in scan-order) as token context. Pearson co
27 mars 2013, par Ronald S. BultjeChanged Paths : Modify /vp9/common/vp9_default_coef_probs.h Modify /vp9/common/vp9_entropy.c Modify /vp9/common/vp9_entropy.h Modify /vp9/common/vp9_onyxc_int.h Modify /vp9/decoder/vp9_decodframe.c Modify /vp9/decoder/vp9_detokenize.c Modify /vp9/encoder/vp9_bitstream.c (...)
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ffplay : estimate audio frame pts from the previous frame pts values
13 juillet 2013, par Marton Balintffplay : estimate audio frame pts from the previous frame pts values
Previously we estimated the audio packet pts instead of the frame pts,
therefore it only worked within a single packet (containing multiple frames).The new method works accross seperate audio packets as well and also handles
better the case if a decoder buffers several packets before outputting a
decoded frame.Signed-off-by : Marton Balint <cus@passwd.hu>
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