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Richard Stallman et le logiciel libre
19 octobre 2011, par
Mis à jour : Mai 2013
Langue : français
Type : Texte
Autres articles (111)
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Multilang : améliorer l’interface pour les blocs multilingues
18 février 2011, parMultilang est un plugin supplémentaire qui n’est pas activé par défaut lors de l’initialisation de MediaSPIP.
Après son activation, une préconfiguration est mise en place automatiquement par MediaSPIP init permettant à la nouvelle fonctionnalité d’être automatiquement opérationnelle. Il n’est donc pas obligatoire de passer par une étape de configuration pour cela. -
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 (...) -
ANNEXE : Les plugins utilisés spécifiquement pour la ferme
5 mars 2010, parLe site central/maître de la ferme a besoin d’utiliser plusieurs plugins supplémentaires vis à vis des canaux pour son bon fonctionnement. le plugin Gestion de la mutualisation ; le plugin inscription3 pour gérer les inscriptions et les demandes de création d’instance de mutualisation dès l’inscription des utilisateurs ; le plugin verifier qui fournit une API de vérification des champs (utilisé par inscription3) ; le plugin champs extras v2 nécessité par inscription3 (...)
Sur d’autres sites (9390)
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M4a (mp4) audio file encoded with pydub+ffmpeg doesn't play on Android
6 juillet 2020, par EvelynI have a python script to split up some
wav
files and export tom4a
using pydub. I'm able to get these files to play on several devices, but not on an Android device (using Google Pixel 3). When I try encoding with straightffmpeg
in terminal, that works fine on the Android device.

What is the difference in these two files, and since
pydub
is usingffmpeg
, what do I need to change to make it do exactly the same as theffmpeg
command ?

Not working


from pydub import AudioSegment
>>> audio = AudioSegment.from_wav("input.wav")
>>> slice = audio[1000:3000]
>>> slice.export("pydub_export.m4a", format="mp4", parameters=["-ac", "1", "-c:a", "libfdk_aac", "-profile:a", "aac_he", "-vbr", "2"])



mediainfo
output :

General
Complete name : pydub_export.m4a
Format : MPEG-4
Format profile : Base Media
Codec ID : isom (isom/iso2/mp41)
File size : 11.7 KiB
Duration : 2 s 115 ms
Overall bit rate mode : Constant
Overall bit rate : 45.1 kb/s
Writing application : Lavf58.29.100

Audio
ID : 1
Format : AAC LC SBR
Format/Info : Advanced Audio Codec Low Complexity with Spectral Band Replication
Commercial name : HE-AAC
Format settings : NBC
Codec ID : mp4a-40-5
Duration : 2 s 115 ms
Duration_LastFrame : -22 ms
Bit rate mode : Constant
Bit rate : 41.4 kb/s
Channel(s) : 1 channel
Channel layout : C
Sampling rate : 44.1 kHz
Frame rate : 21.533 FPS (2048 SPF)
Compression mode : Lossy
Stream size : 10.7 KiB (92%)
Default : Yes
Alternate group : 1



Working


$ffmpeg -i input.wav -acodec copy -ss 1 -to 3 input_slice.wav
$ffmpeg -i input_slice.wav -ac 1 -c:a libfdk_aac -profile:a aac_he -vbr 2 ffmpeg_export.m4a



mediainfo
output :

General
Complete name : ffmpeg_export.m4a
Format : MPEG-4
Format profile : Apple audio with iTunes info
Codec ID : M4A (isom/iso2)
File size : 11.2 KiB
Duration : 2 s 112 ms
Overall bit rate mode : Constant
Overall bit rate : 43.6 kb/s
Writing application : Lavf58.29.100

Audio
ID : 1
Format : AAC LC SBR
Format/Info : Advanced Audio Codec Low Complexity with Spectral Band Replication
Commercial name : HE-AAC
Format settings : NBC
Codec ID : mp4a-40-5
Duration : 2 s 112 ms
Duration_LastFrame : -25 ms
Bit rate mode : Constant
Bit rate : 39.9 kb/s
Channel(s) : 1 channel
Channel layout : C
Sampling rate : 44.1 kHz
Frame rate : 21.533 FPS (2048 SPF)
Compression mode : Lossy
Stream size : 10.3 KiB (91%)
Default : Yes
Alternate group : 1



I already tried moving metadata to the front with
-movflags faststart
on the broken file and it didn't make a difference.

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ffmpeg : remove dead call to av_parser_change()
21 mars 2018, par James Almerffmpeg : remove dead call to av_parser_change()
It's been a noop for years, and it's been argued that in-band headers
should not be forcedly removed without the user's explicit request.Also, as the FIXME line stated, this is a job for a bitstream filter
like extract_extradata, remove_extradata, dump_extradata, and
filter_units.Signed-off-by : James Almer <jamrial@gmail.com>
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Revision bfc27bb614 : tx-skip experiment : improve entropy coding of coeff tokens This patch allows th
31 mars 2015, par hui suChanged Paths :
Modify /vp9/common/vp9_entropy.c
Modify /vp9/common/vp9_entropy.h
Modify /vp9/common/vp9_onyxc_int.h
Modify /vp9/common/vp9_quant_common.c
Modify /vp9/decoder/vp9_detokenize.c
Modify /vp9/encoder/vp9_encodemb.c
Modify /vp9/encoder/vp9_rdopt.c
Modify /vp9/encoder/vp9_tokenize.c
tx-skip experiment : improve entropy coding of coeff tokensThis patch allows the prediction residues of tx-skipped blocks
to use probs that are different from regular transfrom
coefficients for token entropy coding. Prediction residues are
assumed as in band 6.The initial value of probs is obtained with stats from limited
tests. The statistic model for constrained token nodes has not
been optimized. The probs for token extra bits have not been
optimized. These can be future work.Certain coding improvment is observed :
derflr with all experiments : +6.26% (+0.10%)
screen_content with palette : +22.48% (+1.28%)Change-Id : I1c0d78178ee9f3655febb6f30cdaef8ee9f8e3cc