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  • Le profil des utilisateurs

    12 avril 2011, par

    Chaque utilisateur dispose d’une page de profil lui permettant de modifier ses informations personnelle. Dans le menu de haut de page par défaut, un élément de menu est automatiquement créé à l’initialisation de MediaSPIP, visible uniquement si le visiteur est identifié sur le site.
    L’utilisateur a accès à la modification de profil depuis sa page auteur, un lien dans la navigation "Modifier votre profil" est (...)

  • Configurer la prise en compte des langues

    15 novembre 2010, par

    Accéder à la configuration et ajouter des langues prises en compte
    Afin de configurer la prise en compte de nouvelles langues, il est nécessaire de se rendre dans la partie "Administrer" du site.
    De là, dans le menu de navigation, vous pouvez accéder à une partie "Gestion des langues" permettant d’activer la prise en compte de nouvelles langues.
    Chaque nouvelle langue ajoutée reste désactivable tant qu’aucun objet n’est créé dans cette langue. Dans ce cas, elle devient grisée dans la configuration et (...)

  • XMP PHP

    13 mai 2011, par

    Dixit Wikipedia, XMP signifie :
    Extensible Metadata Platform ou XMP est un format de métadonnées basé sur XML utilisé dans les applications PDF, de photographie et de graphisme. Il a été lancé par Adobe Systems en avril 2001 en étant intégré à la version 5.0 d’Adobe Acrobat.
    Étant basé sur XML, il gère un ensemble de tags dynamiques pour l’utilisation dans le cadre du Web sémantique.
    XMP permet d’enregistrer sous forme d’un document XML des informations relatives à un fichier : titre, auteur, historique (...)

Sur d’autres sites (6958)

  • FFmpeg decode H264 video too slowly

    17 décembre 2012, par user1158196

    I am currently working on a project on iPhone using FFMpeg. I can decode all the formats I need but when I want to play a h264 video, ffmpeg decodes frames too slowly.

    I tried to see where the problem is. I think that the options from the compilation of the library are good, decoding and displaying the frames are made ​​on different threads. In the end, it seems that it is the function avcodec_decode_video2 that takes too long (3 to 4 seconds to decode 30 frames).

  • libx264 performances on iOS

    8 mai 2012, par Gilad

    I was wondering whether someone has some experience using libx264 on iPhone.

    How does it perform ? What framerate can I expect ? Will it work for simultaneous encoding & decoding (video call) or the CPU can't handle it ? I'm mainly interested with iPhone 4 and above (iPhone4/iPad 2)

    Are there any precompiled universal binaries I can use ?

  • VP8 for Real-time Video Applications

    15 février 2011, par noreply@blogger.com (John Luther)

    With the growing interest in videoconferencing on the web platform, it’s a good time to explore the features of VP8 that make it an exceptionally good codec for real-time applications like videoconferencing.

    VP8 Design History & Features

    Real-time applications were a primary use case when VP8 was designed. The VP8 encoder has features specifically engineered to overcome the challenges inherent in compressing and transmitting real-time video data.

    • Processor-adaptive encoding. 16 encoder complexity levels automatically (or manually) adjust encoder features such as motion search strategy, quantizer optimizations, and loop filtering strength.
    • Encoder can be configured to use a target percentage of the host CPU.
      Ability to measure the time taken to encode each frame and adjust encoder complexity dynamically to keep the encoding time per frame constant
    • Robust error recovery (packet retransmission, forward error correction, recovery frame/new keyframe requests)
    • Temporal scalability (i.e., a single video bitstream that can degrade as needed depending on a participant’s available bandwidth)
    • Highly efficient decoding performance on low-power devices. Conventional video technology has grown to a state of complexity where dedicated hardware chips are needed to make it work well. With VP8, software-based solutions have proven to meet customer needs without requiring specialized hardware.

    For a more information about real-time video features in VP8, see the slide presentation by WebM Project engineer Paul Wilkins (PDF file).

    Commercially Available Products

    Millions of people around the world have been using VP7/8 for video chat for years. VP8 is deployed in some of today’s most popular consumer videoconferencing applications, including Skype (group video calling), Sightspeed, ooVoo and Logitech Vid. All of these vendors are active WebM project supporters. VP8’s predecessor, VP7, has been used in Skype video calling since 2005 and is supported in the new Skype app for iPhone. Other real-time VP8 implementations are coming soon, including ooVoo, and VP8 will play a leading role in Google’s plans for real-time applications on the web platform.

    Real-time applications will be extremely important as the web platform matures. The WebM community has made significant improvements in VP8 for real-time use cases since our launch and will continue to do so in the future.

    John Luther is Product Manager of the WebM Project.

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