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  • MediaSPIP version 0.1 Beta

    16 avril 2011, par

    MediaSPIP 0.1 beta est la première version de MediaSPIP décrétée comme "utilisable".
    Le fichier zip ici présent contient uniquement les sources de MediaSPIP en version standalone.
    Pour avoir une installation fonctionnelle, il est nécessaire d’installer manuellement l’ensemble des dépendances logicielles sur le serveur.
    Si vous souhaitez utiliser cette archive pour une installation en mode ferme, il vous faudra également procéder à d’autres modifications (...)

  • MediaSPIP 0.1 Beta version

    25 avril 2011, par

    MediaSPIP 0.1 beta is the first version of MediaSPIP proclaimed as "usable".
    The zip file provided here only contains the sources of MediaSPIP in its standalone version.
    To get a working installation, you must manually install all-software dependencies on the server.
    If you want to use this archive for an installation in "farm mode", you will also need to proceed to other manual (...)

  • Personnaliser en ajoutant son logo, sa bannière ou son image de fond

    5 septembre 2013, par

    Certains 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 ;

Sur d’autres sites (10511)

  • ffmpeg : Apply a time-based expr to control intensity of lowpass, highpass, aphaser, or aecho [closed]

    17 mai 2024, par Wes Modes

    I am procedurally constructing complexFilters for ffmpeg via fluent-ffmpeg. My fluent-ffmpeg complex filters look like :

    


    {
   "filter": "volume",
   "options": {
       "volume": "min(1, max(0, ((cos(PI * t * 1 / 13) * 1 + cos(PI * t * 1 / 7) * 0.5 + cos(PI * t * 1 / 3) * 0.25) +
-0.5 ) * 0.75 * -1 + 0.5))",
       "eval": "frame"
    },
    "inputs": "track_1_output",
    "outputs": "track_1_adjusted"
},


    


    Note that I am using an expression to determine the volume dynamically.

    


    Here I'm testing on the command line, to understand the mysteries of lightly-documented ffmpeg filters. I'm fading in and out two sources, intertwined in the output. Now I want to apply lowpass, highpass, aphaser, and/or aecho to the transitions using a time-based expr.

    


    I've already succeeded using the volume filter to fade the sources in and out (Note that the sine has reversed polarity for the second volume filter) :

    


    # working fade in/out
ffmpeg -i knox.mp3 -i static.mp3 -filter_complex \
"[0:a] \
    volume = 'min(1, max(0, 0.5 + 0.5 * cos(PI * t / 5)))': eval=frame \
    [a0]; \
[1:a] \
    volume = 'min(1, max(0, 0.5 - 0.5 * cos(PI * t / 5)))': eval=frame \
    [a1]; \
[a0][a1]
    amix = inputs=2: duration=shortest" \
-c:a libmp3lame -q:a 2 output.mp3


    


    ffmpeg -filters says that lowpass has time-based support :

    


      T.. = Timeline support
 TSC lowpass           A->A       Apply a low-pass filter with 3dB point frequency.


    


    How can I similarly apply these other filters to source1 using a time-bassed expr ? I was unsuccessful in figuring out lowpass and highpass :

    


    # applying a lowpass filter
ffmpeg -i knox.mp3 -i static.mp3 -filter_complex \
"[0:a] \
    volume = 'min(1, max(0, 0.5 + 0.5 * cos(PI * t / 5)))': eval=frame, \
    lowpass=f=3000: mix='0.5 + 0.5 * cos(PI * t / 5)' \
    [a0]; \
[1:a] \
    volume = 'min(1, max(0, 0.5 - 0.5 * cos(PI * t / 5)))': eval=frame \
    [a1]; \
[a0][a1]
    amix = inputs=2: duration=shortest" \
-c:a libmp3lame -q:a 2 output.mp3


    


    With the resultant error :

    


    [Parsed_lowpass_1 @ 0x7f9a72005c00] [Eval @ 0x7ff7bec423d8] Undefined constant or missing '(' in 't/5)'
[Parsed_lowpass_1 @ 0x7f9a72005c00] Unable to parse option value "0.5 + 0.5 * cos(PI * t / 5)"
Error applying option 'mix' to filter 'lowpass': Invalid argument


    


    What complicated fffmpeg faerie magic is needed to make some of the filters other than volume controlled by a time-based expr ?

    


  • Add new build based on jQuery UI build file

    20 mars 2011, par jzaefferer

    + build.xml + build/ant-contrib-0.6.jar + build/google-compiler-20110320.jar Add new build based on jQuery UI build file

  • Revision 903801f1ef : vp9 decoder : row-based multi-threaded loopfilter Implemented parallel loopfilte

    28 décembre 2013, par Yunqing Wang

    Changed Paths :
     Modify /vp9/common/vp9_loopfilter.c


     Modify /vp9/common/vp9_loopfilter.h


     Modify /vp9/decoder/vp9_decodeframe.c


     Add /vp9/decoder/vp9_dthread.c


     Add /vp9/decoder/vp9_dthread.h


     Modify /vp9/decoder/vp9_onyxd_if.c


     Modify /vp9/decoder/vp9_onyxd_int.h


     Modify /vp9/decoder/vp9_thread.c


     Modify /vp9/decoder/vp9_thread.h


     Modify /vp9/vp9dx.mk



    vp9 decoder : row-based multi-threaded loopfilter

    Implemented parallel loopfiltering, which uses existing tile-
    decoding threads. Each thread works on one row, and when that row
    is loopfiltered, it moves to next unattended row. To ensure the
    correct filtering order, threads are synchronized and one
    superblock is filtered only if the superblocks it depends on are
    filtered already.

    To reduce synchronization overhead and speed up the decoder, we use
    nsync > 1 for high resolution.

    Performance tests :
    1. on desktop :
    8-tile 4k video using 8 threads, speedup : 70% - 80%
    4-tile HD video using 4 threads, speedup : 35%
    2. on mobile device(Nexus 7) :
    4-tile 1080p video using 4 threads, speedup : 18% - 25%
    4-tile 1080p video using 2 threads, speedup : 10% - 15%

    Change-Id : If54b4a11960dd706c22d5ad145ad94156031f36a

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