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  • Les autorisations surchargées par les plugins

    27 avril 2010, par

    Mediaspip core
    autoriser_auteur_modifier() afin que les visiteurs soient capables de modifier leurs informations sur la page d’auteurs

  • Publier sur MédiaSpip

    13 juin 2013

    Puis-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

  • HTML5 audio and video support

    13 avril 2011, par

    MediaSPIP 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 (...)

Sur d’autres sites (8632)

  • lavc/libvpx : increase thread limit to 64

    6 octobre 2022, par OvchinnikovDmitrii
    lavc/libvpx : increase thread limit to 64

    This change improves the performance and multicore scalability of the vp9
    
codec for streaming single-pass encoded videos by taking advantage of up
    
to 64 cores in the system. The current thread limit for ffmpeg codecs is 16
    
(MAX_AUTO_THREADS in pthread_internal.h) due to a limitation in H.264 codec
    
that prevents more than 16 threads being used.
    

    Experiments show that increasing the thread limit to 64 for vp9 improves
    
the performance for encoding 4K raw videos for streaming by up to 47%
    
compared to 16 threads, and from 20-30% for 32 threads, with the same quality
    
as measured by the VMAF score.
    

    Rationale for this change :
    
Vp9 uses tiling to split the video frame into multiple columns ; tiles must
    
be at least 256 pixels wide, so there is a limit to how many tiles can be
    
used. The tiles can be processed in parallel, and more tiles mean more CPU
    
threads can be used. 4K videos can make use of 16 threads, and 8K videos
    
can use 32. Row-mt can double the number of threads so 64 threads can be used.
    

    Signed-off-by : James Zern <jzern@google.com>
    • [DH] libavcodec/libvpx.h
    • [DH] libavcodec/libvpxdec.c
    • [DH] libavcodec/libvpxenc.c

  • avfilter/vf_[color/chroma]key : lower lower limit for similarity option

    27 octobre 2022, par Paul B Mahol
    avfilter/vf_[color/chroma]key : lower lower limit for similarity option
    • [DH] libavfilter/vf_chromakey.c
    • [DH] libavfilter/vf_colorkey.c

  • avformat/yuv4mpegdec : increase header limit

    20 octobre 2022, par Chema Gonzalez
    avformat/yuv4mpegdec : increase header limit

    Allows demuxing UHD F1000000000:33333333 fps yuvj420p files
    

    ffmpeg (at HEAD as of now) is creating this :
    

    ```
    
$ ffmpeg -y -i source.265 /tmp/foo.y4m >& /dev/null
    
...
    
$ xxd /tmp/raw.y4m |less
    
00000000 : 5955 5634 4d50 4547 3220 5731 3932 3020  YUV4MPEG2 W1920
    
00000010 : 4831 3038 3020 4631 3030 3030 3030 3030  H1080 F100000000
    
00000020 : 303a 3333 3333 3333 3333 2049 7020 4130  0:33333333 Ip A0
    
00000030 : 3a30 2043 3432 306d 7065 6732 2058 5953  :0 C420mpeg2 XYS
    
00000040 : 4353 533d 3432 304d 5045 4732 2058 434f  CSS=420MPEG2 XCO
    
00000050 : 4c4f 5252 414e 4745 3d4c 494d 4954 4544  LORRANGE=LIMITED
    
00000060 : 0a46 5241 4d45 0a82 8282 8282 8282 8282  .FRAME..........
    
...
    
```
    

    Which cannot be parsed by the same ffmpeg decoder :
    
```
    
$ ffmpeg -i /tmp/foo.y4m /tmp/bar.y4m
    
...
    
[yuv4mpegpipe @ 0x2b69a40] Header too large.
    
/tmp/foo.y4m : Invalid argument
    
```
    

    This is kicking the ball (per 0b1ff3265e9bdad3b4b6b97ced2f126cb3599568),
    
but seems to work.
    • [DH] libavformat/yuv4mpegdec.c

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