Recherche avancée

Médias (0)

Mot : - Tags -/clipboard

Aucun média correspondant à vos critères n’est disponible sur le site.

Autres articles (96)

  • Les sons

    15 mai 2013, par
  • Automated installation script of MediaSPIP

    25 avril 2011, par

    To overcome the difficulties mainly due to the installation of server side software dependencies, an "all-in-one" installation script written in bash was created to facilitate this step on a server with a compatible Linux distribution.
    You must have access to your server via SSH and a root account to use it, which will install the dependencies. Contact your provider if you do not have that.
    The documentation of the use of this installation script is available here.
    The code of this (...)

  • MediaSPIP en mode privé (Intranet)

    17 septembre 2013, par

    À partir de la version 0.3, un canal de MediaSPIP peut devenir privé, bloqué à toute personne non identifiée grâce au plugin "Intranet/extranet".
    Le plugin Intranet/extranet, lorsqu’il est activé, permet de bloquer l’accès au canal à tout visiteur non identifié, l’empêchant d’accéder au contenu en le redirigeant systématiquement vers le formulaire d’identification.
    Ce système peut être particulièrement utile pour certaines utilisations comme : Atelier de travail avec des enfants dont le contenu ne doit pas (...)

Sur d’autres sites (11682)

  • Revision 195061feda : Fix rectangular partition check in speed 1 Make encoder skip rectangular partit

    30 septembre 2013, par Jingning Han

    Changed Paths :
     Modify /vp9/encoder/vp9_encodeframe.c



    Fix rectangular partition check in speed 1

    Make encoder skip rectangular partition check in speed 1 and above,
    when early termination was triggered in partition split.
    Thanks Guillaume (gmartres@) for catching this issue.

    This change makes bus_cif at 2000kbps speed 1 runtime goes down from
    25612ms to 23438ms (about 9% speed-up), at the expense of -0.235%
    performance down.

    Change-Id : I98613fad081a261d30d5fa206f934ca70601c180

  • Revision df90d58f4f : Speed up motion estimation using small partitions' result(experiment) Current p

    3 juillet 2013, par Yunqing Wang

    Changed Paths :
     Modify /vp9/encoder/vp9_block.h


     Modify /vp9/encoder/vp9_encodeframe.c


     Modify /vp9/encoder/vp9_onyx_if.c


     Modify /vp9/encoder/vp9_onyx_int.h


     Modify /vp9/encoder/vp9_rdopt.c



    Speed up motion estimation using small partitions' result(experiment)

    Current partition checking starts from small sizes, and then goes up
    to large sizes. This experiment uses the small partitions' motion
    estimation result, which is already available, to speed up the
    large partition's motion estimation. We can decide to skip some
    patition checkings if they are unlikely choices. We could use the
    motion vector(MV) result as current partition's prediction MV, limit
    the search range and reference frame.

    Current result at speed 1 :
    psnr loss : 1.19% for stdhd, 0.287% for derf.
    speed gain : 14% for sunflower(hd), 11% for akiyo.

    Further improvement will be done later.

    Change-Id : I5abfd070e9cace2e91e2a0247d1325df313887ab

  • Revision faff6ed0fb : Skip duplicate block encoding in the rd loop This speed feature allows the enco

    9 juillet 2013, par Jingning Han

    Changed Paths :
     Modify /vp9/encoder/vp9_block.h


     Modify /vp9/encoder/vp9_encodeframe.c


     Modify /vp9/encoder/vp9_encodeintra.c


     Modify /vp9/encoder/vp9_encodemb.c


     Modify /vp9/encoder/vp9_onyx_if.c


     Modify /vp9/encoder/vp9_onyx_int.h


     Modify /vp9/encoder/vp9_rdopt.c


     Modify /vp9/encoder/vp9_rdopt.h



    Skip duplicate block encoding in the rd loop

    This speed feature allows the encoder to largely remove the spatial
    dependency between blocks inside a 64x64 superblock, thereby removing
    the need to repeatedly encode superblocks per partition type in the
    rate-distortion optimization loop.

    A major challenge lies in the intra modes tested in the rate-distortion
    optimization loop. The subsequent blocks do not have access to the
    reconstructed boundary pixels without the intermediate coding steps.
    This was resolved by using the original pixels for intra prediction
    in the rd loop, followed by an appropriately designed distortion
    modeling on the quantization parameters. Experiments also suggested
    that the performance impact is more discernible at lower bit-rate/psnr
    settings. Hence a quantizer dependent threshold is applied to deactivate
    skip of block coding.

    For bus_cif at 2000 kbps,
    speed 0 : runtime 269854ms -> 237774ms (12% speed-up) at 0.05dB
    performance loss.

    speed 1 : runtime 65312ms -> 61536ms, (7% speed-up) at 0.04dB
    performance loss.

    This operation is currently turned on in settings of speed 1.

    Change-Id : Ib689741dfff8dd38365d8c1b92860a3e176f56ec