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Médias (3)
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MediaSPIP Simple : futur thème graphique par défaut ?
26 septembre 2013, par
Mis à jour : Octobre 2013
Langue : français
Type : Video
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GetID3 - Bloc informations de fichiers
9 avril 2013, par
Mis à jour : Mai 2013
Langue : français
Type : Image
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GetID3 - Boutons supplémentaires
9 avril 2013, par
Mis à jour : Avril 2013
Langue : français
Type : Image
Autres articles (57)
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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 -
Personnaliser en ajoutant son logo, sa bannière ou son image de fond
5 septembre 2013, parCertains thèmes prennent en compte trois éléments de personnalisation : l’ajout d’un logo ; l’ajout d’une bannière l’ajout d’une image de fond ;
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Emballe médias : à quoi cela sert ?
4 février 2011, parCe plugin vise à gérer des sites de mise en ligne de documents de tous types.
Il crée des "médias", à savoir : un "média" est un article au sens SPIP créé automatiquement lors du téléversement d’un document qu’il soit audio, vidéo, image ou textuel ; un seul document ne peut être lié à un article dit "média" ;
Sur d’autres sites (10383)
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7 Best Marketing Attribution Software in 2024
22 février 2024, par Erin -
opus : add a native Opus encoder
11 février 2017, par Rostislav Pehlivanovopus : add a native Opus encoder
This marks the first time anyone has written an Opus encoder without
using any libopus code. The aim of the encoder is to prove how far
the format can go by writing the craziest encoder for it.Right now the encoder’s basic, it only supports CBR encoding, however
internally every single feature the CELT layer has is implemented
(except the pitch pre-filter which needs to work well with the rest of
whatever gets implemented). Psychoacoustic and rate control systems are
under development.The encoder takes in frames of 120 samples and depending on the value of
opus_delay the plan is to use the extra buffered frames as lookahead.
Right now the encoder will pick the nearest largest legal frame size and
won’t use the lookahead, but that’ll change once there’s a
psychoacoustic system.Even though its a pretty basic encoder its already outperforming
any other native encoder FFmpeg has by a huge amount.The PVQ search algorithm is faster and more accurate than libopus’s
algorithm so the encoder’s performance is close to that of libopus
at zero complexity (libopus has more SIMD).
The algorithm might be ported to libopus or other codecs using PVQ in
the future.The encoder still has a few minor bugs, like desyncs at ultra low
bitrates (below 9kbps with 20ms frames).Signed-off-by : Rostislav Pehlivanov <atomnuker@gmail.com>
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How to convert VP8 track with different frame resolution to h264
13 septembre 2016, par NikitaI have a .webm file with VP8 track, recorded from WebRTC stream by external service (TokBox Archiving). The stream is adaptive, so each frame in track could have different resolution. Most players (in webkit browsers) use video resolution from track description (which is always 640x480) and scale frames to this resolution. Firefox and VLC player uses real frame resolution, changing video resolution respectively.
I want to achieve 2 goals :
- play this video in Internet Explorer 9+ without additional plugin installation.
- change frames resolution to one fixed resolution, so the video will look identically in different browsers.
So, my plan is :
- extract frames from source webm file to images with real frame resolution (e.g. PNG or BMP) (how could I do that ?)
- find max width and max height of images
- add black padding to images, so smaller frames will be in the center of a new frame (of size MAX_WIDHTxMAX_HEIGHT)
- combine images to h264 track using ffmpeg
Is all correct ? How can I achieve this ? Can this algorithm be optimized some way ?
I tried ffmpeg to extract images, but it does not parse real frame resolution, using resolution from track header.
I think some libwebm functions can help me (to parse frame headers and extract images). Maybe someone has some code snippets to do this ?Example .webm (download source, do not play google-converted version) : https://drive.google.com/file/d/0BwFZRvYNn9CKcndhMzlVa0psX00/view?usp=sharing
Official description of adaptive stream from TokBox support : https://support.tokbox.com/hc/en-us/community/posts/206241666-Archived-video-resolution-is-supposed-to-be-720x1280-but-reports-as-640x480