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  • Multilang : améliorer l’interface pour les blocs multilingues

    18 février 2011, par

    Multilang est un plugin supplémentaire qui n’est pas activé par défaut lors de l’initialisation de MediaSPIP.
    Après son activation, une préconfiguration est mise en place automatiquement par MediaSPIP init permettant à la nouvelle fonctionnalité d’être automatiquement opérationnelle. Il n’est donc pas obligatoire de passer par une étape de configuration pour cela.

  • Des sites réalisés avec MediaSPIP

    2 mai 2011, par

    Cette page présente quelques-uns des sites fonctionnant sous MediaSPIP.
    Vous pouvez bien entendu ajouter le votre grâce au formulaire en bas de page.

  • De l’upload à la vidéo finale [version standalone]

    31 janvier 2010, par

    Le chemin d’un document audio ou vidéo dans SPIPMotion est divisé en trois étapes distinctes.
    Upload et récupération d’informations de la vidéo source
    Dans un premier temps, il est nécessaire de créer un article SPIP et de lui joindre le document vidéo "source".
    Au moment où ce document est joint à l’article, deux actions supplémentaires au comportement normal sont exécutées : La récupération des informations techniques des flux audio et video du fichier ; La génération d’une vignette : extraction d’une (...)

Sur d’autres sites (6092)

  • Quicktime Eats Cookies

    20 septembre 2009

    It appears that when embedding Quicktime in a webpage, being viewed by Safari 4 in Snow Leopard, Quicktime no longer passes cookies to the server. So, if you’re having the Quicktime plugin load a file that uses cookie data to verify permissions, you’ll need to move to a query string model.

    This only happens when Safari is running in 64bit mode, so I imagine it has to do with the "plugins running as separate entities" crash protection that Snow Leopard adds.

    This does not appear to impact the Flash plugin.

  • VP8 Codec Optimization Update

    16 juin 2010, par noreply@blogger.com (John Luther) — inside webm

    Since WebM launched in May, the team has been working hard to make the VP8 video codec faster. Our community members have contributed improvements, but there’s more work to be done in some interesting areas related to performance (more on those below).


    Encoder


    The VP8 encoder is ripe for speed optimizations. Scott LaVarnway’s efforts in writing an x86 assembly version of the quantizer will help in this goal significantly as the quantizer is called many times while the encoder makes decisions about how much detail from the image will be transmitted.

    For those of you eager to get involved, one piece of low-hanging fruit is writing a SIMD version of the ARNR temporal filtering code. Also, much of the assembly code only makes use of the SSE2 instruction set, and there surely are newer extensions that could be made use of. There are also redundant code removal and other general cleanup to be done ; (Yaowu Xu has submitted some changes for these).

    At a higher level, someone can explore some alternative motion search strategies in the encoder. Eventually the motion search can be decoupled entirely to allow motion fields to be calculated elsewhere (for example, on a graphics processor).

    Decoder


    Decoder optimizations can bring higher resolutions and smoother playback to less powerful hardware.

    Jeff Muizelaar has submitted some changes which combine the IDCT and summation with the predicted block into a single function, helping us avoid storing the intermediate result, thus reducing memory transfers and avoiding cache pollution. This changes the assembly code in a fundamental way, so we will need to sync the other platforms up or switch them to a generic C implementation and accept the performance regression. Johann Koenig is working on implementing this change for ARM processors, and we’ll merge these changes into the mainline soon.

    In addition, Tim Terriberry is attacking a different method of bounds checking on the "bool decoder." The bool decoder is performance-critical, as it is called several times for each bit in the input stream. The current code handles this check with a simple clamp in the innermost loops and a less-frequent copy into a circular buffer. This can be expensive at higher data rates. Tim’s patch removes the circular buffer, but uses a more complex clamp in the innermost loops. These inner loops have historically been troublesome on embedded platforms.

    To contribute in these efforts, I’ve started working on rewriting higher-level parts of the decoder. I believe there is an opportunity to improve performance by paying better attention to data locality and cache layout, and reducing memory bus traffic in general. Another area I plan to explore is improving utilization in the multi-threaded decoder by separating the bitstream decoding from the rest of the image reconstruction, using work units larger than a single macroblock, and not tying functionality to a specific thread. To get involved in these areas, subscribe to the codec-devel mailing list and provide feedback on the code as it’s written.

    Embedded Processors


    We want to optimize multiple platforms, not just desktops. Fritz Koenig has already started looking at the performance of VP8 on the Intel Atom platform. This platform need some attention as we wrote our current x86 assembly code with an out-of-order processor in mind. Since Atom is an in-order processor (much like the original Pentium), the instruction scheduling of all of the x86 assembly code needs to be reexamined. One option we’re looking at is scheduling the code for the Atom processor and seeing if that impacts the performance on other x86 platforms such as the Via C3 and AMD Geode. This is shaping up to be a lot of work, but doing it would provide us with an opportunity to tighten up our assembly code.

    These issues, along with wanting to make better use of the larger register file on x86_64, may reignite every assembly programmer’s (least ?) favorite debate : whether or not to use intrinsics. Yunqing Wang has been experimenting with this a bit, but initial results aren’t promising. If you have experience in dealing with a lot of assembly code across several similar-but-kinda-different platforms, these maintainability issues might be familiar to you. I hope you’ll share your thoughts and experiences on the codec-devel mailing list.

    Optimizing codecs is an iterative (some would say never-ending) process, so stay tuned for more posts on the progress we’re making, and by all means, start hacking yourself.

    It’s exciting to see that we’re starting to get substantial code contributions from developers outside of Google, and I look forward to more as WebM grows into a strong community effort.

    John Koleszar is a software engineer at Google.

  • Podcast Producer 2 REST api

    11 septembre 2009

    I’ve been working on documenting the REST api that PCP2 uses for client server communication as part of a new project. I thought it might be useful to other folks. Consider this a work in progress - I’ve only documented the workflow for doing a multisource recording so far. Follow the job for the info.

    Each section gives a sample command and a sample response.

    All pages are behind basic HTTP auth.

    General sequence of events

    * get workflow list
    * get cameras
    * request status for camera (including thumbnail)
    * start cameras
    * create recording enclosure
    * stop cameras, provide submission_UUID returned by above step, include title

    *URL : https://pcpserver:8170/podcastproducer/info

    *Type : GET

    *Content : version=2

    *Response :
    <pre>
    <podcast_producer_result>
    <action>index</action>
    <status>success</status>
    <plist version="1.0">
    <dict>
    <key>server_version</key>
    <string>2.0</string>
    <key>http_auth_type</key>
    <array>
    <string>basic</string>
    <string>digest</string>
    <string>kerberos</string>
    </array>
    <key>krb_service_principals</key>
    <array>
    <string>pcast/x101-186-103-dhcp.cla.umn.edu@X101-186-103-DHCP.CLA.UMN.EDU</string>
    </array>
    <key>server_uuid</key>
    <string>DB31DA49-10AE-472C-B3B9-86A8F8112399</string>
    <key>cluster_members</key>
    <dict>
    <key>F1021B98-7E7E-44FB-8EB1-E0DA1885D5BA</key>
    <dict>
    <key>date_added</key>
    <string>Tue Sep 01 10:23:49 -0500 2009</string>
    <key>last_update</key>
    <string>Tue Sep 08 10:35:17 -0500 2009</string>
    <key>server_host</key>
    <string>x101-186-103-dhcp.cla.umn.edu</string>
    <key>server_port</key>
    <string>8170</string>
    <key>tunnel_agent_host</key>
    <string>x101-186-103-dhcp.cla.umn.edu</string>
    <key>tunnel_agent_port</key>
    <string>8175</string>
    <key>network_addrs</key>
    <array>
    <string>128.101.186.103</string>
    </array>
    </dict>
    </dict>
    </dict>
    </plist>
    </podcast_producer_result>
    </pre>

    * URL : https://pcpserver:8170/podcastproducer/workflows
    * Type : GET
    * Content : version=2&language=en
    * Response :
    <pre>
    <podcast_producer_result>
    <action>index</action>
    <status>success</status>
    <results>OK</results>
    <plist version="1.0">
    <dict>
    <key>user_fullname</key>
    <string>podcast</string>
    <key>user_shortname</key>
    <string>podcast</string>
    <key>workflows</key>
    <array>
    <dict>
    <key>name</key>
    <string>Montage</string>
    <key>title</key>
    <string>Montage</string>
    <key>description</key>
    <string>Montage workflow</string>
    <key>uuid</key>
    <string>F797D54D-1539-42AA-B6AC-3CB3A4C15EF5</string>
    <key>version</key>
    <string>2.0</string>
    <key>editor</key>
    <string>Podcast Composer</string>
    <key>sources</key>
    <array>
    <dict>
    <key>contentTypes</key>
    <array>
    <string>com.apple.quicktime-movie</string>
    <string>com.adobe.pdf</string>
    <string>com.apple.iwork.keynote.key</string>
    <string>com.apple.iwork.pages.pages</string>
    <string>org.openxmlformats.wordprocessingml.document</string>
    <string>com.microsoft.word.doc</string>
    <string>org.openxmlformats.presentationml.presentation</string>
    <string>com.microsoft.powerpoint.ppt</string>
    <string>com.microsoft.bmp</string>
    <string>com.compuserve.gif</string>
    <string>public.jpeg-2000</string>
    <string>public.jpeg</string>
    <string>com.adobe.pdf</string>
    <string>com.apple.pict</string>
    <string>public.png</string>
    <string>com.adobe.photoshop-image</string>
    <string>com.sgi.sgi-image</string>
    <string>com.truevision.tga-image</string>
    <string>public.tiff</string>
    </array>
    <key>description</key>
    <string>Any Document</string>
    <key>isFolder</key>
    <true/>
    <key>isOptional</key>
    <false/>
    <key>sourceTypes</key>
    <array>
    <string>File</string>
    </array>
    </dict>
    </array>
    <key>user_requirements</key>
    <array>
    <string>Title</string>
    <string>Description</string>
    </array>
    <key>access_control_entries</key>
    <array>
    </array>
    </dict>
    <dict>
    <key>name</key>
    <string>Single Source</string>
    <key>title</key>
    <string>Single Source</string>
    <key>description</key>
    <string>Single Source workflow</string>
    <key>uuid</key>
    <string>DEFA1587-A650-426E-92DA-01C5EB811705</string>
    <key>version</key>
    <string>2.0</string>
    <key>editor</key>
    <string>Podcast Composer</string>
    <key>sources</key>
    <array>
    <dict>
    <key>contentTypes</key>
    <array>
    <string>com.apple.quicktime-movie</string>
    </array>
    <key>description</key>
    <string>Any Video</string>
    <key>isFolder</key>
    <false/>
    <key>isOptional</key>
    <false/>
    <key>sourceTypes</key>
    <array>
    <string>Video</string>
    <string>Screen</string>
    <string>Audio</string>
    <string>File</string>
    </array>
    </dict>
    </array>
    <key>user_requirements</key>
    <array>
    <string>Title</string>
    <string>Description</string>
    </array>
    <key>access_control_entries</key>
    <array>
    </array>
    </dict>
    </array>
    </dict>
    </plist>
    </podcast_producer_result>
    </pre>
    ----

    * URL : https://pcpserver:8170/podcastproducer/cameras
    * Type : GET
    * Content : version=2
    * Response :
    <pre>
    <podcast_producer_result>
    <action>index</action>
    <status>success</status>
    <plist version="1.0">
    <dict>
    <key>cameras</key>
    <array>
    <dict>
    <key>name</key>
    <string>150-A Camera</string>
    <key>uuid</key>
    <string>307682A5-B552-4AFA-B7E2-3811D772C9A1</string>
    <key>connected_to_member_uuid</key>
    <string>F1021B98-7E7E-44FB-8EB1-E0DA1885D5BA</string>
    <key>in_use</key>
    <string>false</string>
    <key>recording_status</key>
    <string>online</string>
    <key>preview_url</key>
    <string>https://x101-186-103-dhcp.cla.umn.edu:8170/podcastproducer/previews/307682A5-B552-4AFA-B7E2-3811D772C9A1.jpg</string> ;
    <key>access_control_entries</key>
    <array>
    </array>
    </dict>
    <dict>
    <key>name</key>
    <string>150-A Epiphan</string>
    <key>uuid</key>
    <string>CE610AB0-CA50-49EB-8FFE-78E57CDCA550</string>
    <key>connected_to_member_uuid</key>
    <string>F1021B98-7E7E-44FB-8EB1-E0DA1885D5BA</string>
    <key>in_use</key>
    <string>false</string>
    <key>recording_status</key>
    <string>online</string>
    <key>preview_url</key>
    <string>https://x101-186-103-dhcp.cla.umn.edu:8170/podcastproducer/previews/CE610AB0-CA50-49EB-8FFE-78E57CDCA550.jpg</string> ;
    <key>access_control_entries</key>
    <array>
    </array>
    </dict>
    </array>
    </dict>
    </plist>
    </podcast_producer_result>
    </pre>

    * URL : https://pcpserver:8170/podcastproducer/cameras/start
    * Type : POST
    * Content : action=pause&version=2&camera_name=150-A%20Camera&controller=cameras
    * Response :
    <pre>
    <podcast_producer_result>
    <action>start</action>
    <status>success</status>
    <results>OK</results>
    </podcast_producer_result>
    </pre>

    * URL : https://pcpserver:8170/podcastproducer/cameras/status
    * Type : POST
    * Content : delay=0&action=start&version=2&camera_name=150-A%20Epiphan&controller=cameras
    * Response :
    <pre><podcast_producer_result>
    <action>status</action>
    <status>success</status>
    <results>OK</results>
    <plist version="1.0">
    <dict>
    <key>preview</key>
    <string>https://x101-186-103-dhcp.cla.umn.edu:8170/podcastproducer/previews/307682A5-B552-4AFA-B7E2-3811D772C9A1.jpg</string> ;
    <key>preview_image_data</key>
    <string>RAW JPEG DATA RAW JPEG DATA RAW JPEG DATA RAW JPEG DATA RAW JPEG DATA</string>
    <key>recording_status</key>
    <string>online</string>
    <key>started_at</key>
    <string>Tue Sep 08 09:31:40 -0500 2009</string>
    <key>stopped_at</key>
    <string>Tue Sep 08 09:32:10 -0500 2009</string>
    <key>elapsed</key>
    <string>41</string>
    <key>last_error</key>
    <string>805306368</string>
    </dict>
    </plist>
    </podcast_producer_result>
    </pre>

    * URL : https://pcpserver:8170/podcastproducer/cameras/pause
    * Type : POST
    * Content : action=pause&version=2&camera_name=150-A%20Camera&controller=cameras
    * Response :
    <pre><podcast_producer_result>
    <action>status</action>
    <status>success</status>
    <results>OK</results>
    <plist version="1.0">
    <dict>
    <key>preview</key>
    <string>https://x101-186-103-dhcp.cla.umn.edu:8170/podcastproducer/previews/307682A5-B552-4AFA-B7E2-3811D772C9A1.jpg</string> ;
    <key>recording_status</key>
    <string>online</string>
    <key>started_at</key>
    <string>Tue Sep 08 09:31:40 -0500 2009</string>
    <key>stopped_at</key>
    <string>Tue Sep 08 09:32:10 -0500 2009</string>
    <key>elapsed</key>
    <string>41</string>
    <key>last_error</key>
    <string>805306368</string>
    </dict>
    </plist>
    </podcast_producer_result></pre>

    * URL : https://pcpserver:8170/podcastproducer/cameras/stop
    * Type : POST
    * Content : workflow_name=&UserMetadata_Description=&submission_uuid=7497E3AC-0A75-4C7C-8C66-26294C9274FE&action=stop&version=2&camera_name=150-A%20Epiphan&controller=cameras&UserMetadata_Title=Test123
    * Response :
    <pre><podcast_producer_result>
    <action>stop</action>
    <status>success</status>
    <results>OK</results>
    </podcast_producer_result>
    </pre>

    * URL : https://pcpserver:8170/podcastproducer/recordings/create
    * Type : POST
    * Content : version=2&workflow_uuid=C6EF52A7-04E3-477D-9F38-6B61F108D7B9
    * Response :
    <pre>
    <podcast_producer_result>
    <action>create</action>
    <status>success</status>
    <results>OK</results>
    <plist version="1.0">
    <dict>
    <key>workflow_uuid</key>
    <string>C6EF52A7-04E3-477D-9F38-6B61F108D7B9</string>
    <key>recording_uuid</key>
    <string>FD5A1459-F7CE-41FA-8155-049DF774298B</string>
    <key>submission_uuids</key>
    <array>
    <string>A626D8E4-E439-4E57-9982-DB4BD035CB41</string>
    <string>CFBCCB74-A41F-42D3-BEAA-58165B1116C6</string>
    </array>
    </dict>
    </plist>
    </podcast_producer_result>
    </pre>

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