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  • Gestion générale des documents

    13 mai 2011, par

    MédiaSPIP ne modifie jamais le document original mis en ligne.
    Pour chaque document mis en ligne il effectue deux opérations successives : la création d’une version supplémentaire qui peut être facilement consultée en ligne tout en laissant l’original téléchargeable dans le cas où le document original ne peut être lu dans un navigateur Internet ; la récupération des métadonnées du document original pour illustrer textuellement le fichier ;
    Les tableaux ci-dessous expliquent ce que peut faire MédiaSPIP (...)

  • Les vidéos

    21 avril 2011, par

    Comme les documents de type "audio", Mediaspip affiche dans la mesure du possible les vidéos grâce à la balise html5 .
    Un des inconvénients de cette balise est qu’elle n’est pas reconnue correctement par certains navigateurs (Internet Explorer pour ne pas le nommer) et que chaque navigateur ne gère en natif que certains formats de vidéos.
    Son avantage principal quant à lui est de bénéficier de la prise en charge native de vidéos dans les navigateur et donc de se passer de l’utilisation de Flash et (...)

  • Les formats acceptés

    28 janvier 2010, par

    Les commandes suivantes permettent d’avoir des informations sur les formats et codecs gérés par l’installation local de ffmpeg :
    ffmpeg -codecs ffmpeg -formats
    Les format videos acceptés en entrée
    Cette liste est non exhaustive, elle met en exergue les principaux formats utilisés : h264 : H.264 / AVC / MPEG-4 AVC / MPEG-4 part 10 m4v : raw MPEG-4 video format flv : Flash Video (FLV) / Sorenson Spark / Sorenson H.263 Theora wmv :
    Les formats vidéos de sortie possibles
    Dans un premier temps on (...)

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  • Piwik 1.12, New Features, API Improvements, Stability — The Last Piwik 1.X Release

    30 mai 2013, par Piwik team — Development

    We are very excited to announce the immediate availability of Piwik v1.12 !

    Piwik v1.12 is a major new release with four big new features, seven smaller new features, several API improvements and all together 82 tickets fixed. This is also the last major 1.X release, which means after this release we will be working on releasing Piwik 2.0. This also means that you should upgrade to PHP 5.3 or higher if you haven’t already, since Piwik 2.0 will only support PHP 5.3 and above.

    Finally, this release contains two breaking changes to the API. If you use the Piwik API click here or scroll down to see if you’re affected.

    Table of Contents :

    New Big Feature – Beta Release Channel

    beta_channel_settings

    For those of you who want to help test Piwik 2.0-beta releases as soon as they come up, we’ve made it easier to use our beta releases. Navigate to the Settings > General Settings page and click the The latest beta release radio button. You will then be able to upgrade to beta releases.

    This isn’t truly a major feature, but we think it’s just as important because it will allow us to create more beta releases and thus catch more bugs before we make a final release. This means more releases and more stability for you.

    New Big Feature – Segment Editor

    Custom Segment Editor with Custom Variable segmentation

    The Segment Editor is a long-awaited new feature that allows you to view, save and edit your segments.

    Piwik has supported segmentation (filtering visits and reports by arbitrary criteria, like browser family) for quite some time now, but it has never been possible to visually create and modify them. Nor could they be saved for later recall.

    Thanks to the eighty individuals and company who funded this feature, it is now possible to :

    • visually segment your visitors, instead of creating URLs.
    • save segments and easily switch between them, instead of remembering URLs.
    • get suggestions for segments that might be helpful to view.
    • learn more in the Segmentating Analytics reports user documentation..

    New Big Feature – Page Speed Reports

    You can now see how long it took your webserver to generate and send pages over HTTP through the new Avg. Generation Time metric.

    This metric can be viewed on both the Pages and Page Titles reports :

    avg_generation_time_page_urls

    And the average page generation time for all the pages in your website/webapp is displayed on the visitors overview :

    avg_generation_time_overview

    You can use this new information to benchmark your webapp and web server.

    New Big Feature – Device Detection Reports

    Piwik 1.12 also includes a new plugin that provides reports on the device types (tablet, desktop, smartphone, etc.), device brands (Apple, Google, Samsung, etc.) and device models (iPad, Nexus 7, etc.) your visitors use to access your website :

    device_reports

    The new plugin also enhances Operating system detections (detecting sub versions of Linux, Windows, and more).

    Note : This plugin is not enabled by default, but will be in Piwik 2.0. If you want to view these reports now, you can activate the plugin in the Installed Plugins admin page. Navigate to Visitors > Devices to see the new reports. You may also use the new (beta) ‘Device type’.

    The new plugin was developed with the support of Clearcode.cc our technology partner

    Other improvements

    Majestic SEO Metrics

    seo_stats_with_majestic

    We’ve added two new SEO metrics to the SEO widget, both of which are calculated by MajesticSEO.com. These metrics will tell you the number of external backlinks (the number of links to your site from other sites) and the number of referrer domains (the number of domains that link to your site).

    We thank the team at Majestic for their support and hard work in bringing you these metrics to your Piwik dashboards !

    Real-time Visitor Count Dashboard Widget

    Real time visitor counter

    There is now a simple new widget you can use to see the number of visitors, visits and actions that occurred in the last couple minutes. We call it the Real Time Visitor Counter !

    New segment parameter : siteSearchKeyword.

    There is now a new segment parameter you can use to segment your visits : siteSearchKeyword. This parameter will let you select visits that had site searches with a specific keyword.

    Ignore URL letter case when importing log files.

    We’ve added a new option to the log import script, –force-lowercase-path. When used, the importer will change URL paths to lowercase before tracking them. This way http://domain.com/MY/BLOG will be treated the same as http://domain.com/my/blog.

    Updated ISP Names

    pretty_provider_names

    We’ve also modified the Providers report so prettier and more up-to-date names of ISPs are displayed.

    Customize the background/text/axis color of graphs.

    custom_image_graph_colors

    It is now possible to change the background color, text color and/or axis color of the graph images generated by the ImageGraph plugin. To access this functionality, use the following URL query parameters when generating an image :

    • backgroundColor
    • textColor
    • axisColor

    For example :

    http://demo.piwik.org/index.php?module=API&method=ImageGraph.get&idSite=7&apiModule=UserSettings&apiAction=getBrowser&token_auth=anonymous&period=day&date=2013-03-21,2013-04-19&language=en&width=779&height=150&fontSize=9&showMetricTitle=0&aliasedGraph=1&legendAppendMetric=0&backgroundColor=efefef&gridColor=dcdcdc&colors=cb2026

    Send your users to a custom URL after they logout.

    If you manage a Piwik installation with many users and you want to send them to a custom page or website after they log out of Piwik, you can now specify the URL to redirect users after they log out.

    API Changes and Improvements

    BREAKING CHANGE – renamed segment parameters.

    The following segment parameters have been renamed :

    • continent renamed to : continentCode
    • browserName renamed to : browserCode
    • operatingSystem renamed to : operatingSystemCode
    • lat renamed to : latitude
    • long renamed to : longitude
    • region renamed to : regionCode
    • country renamed to : countryCode
    • continent renamed to : continentCode

    If you use one of the old segment parameter names, Piwik will throw an exception, so you should notice when you’re using an old name.

    BREAKING CHANGE – changes to the input & output of the Live.getLastVisitsDetails method.

    The following changes were made to the Live.getLastVisitsDetails API method :

    • The method no longer uses the maxIdVisit query parameter. It has been replaced by the filter_offset parameter.
    • Site search keywords are now displayed in a <siteSearchKeyword> element. They were formerly in <pageTitle> elements.
    • Custom variables with page scope now have ‘Page’ in their element names when displayed. For example, <customVariablePageName1>, <customVariablePageName2>, etc.

    Filter results of MultiSites.getAll by website name.

    It is now possible to filter the results of MultiSites.getAll by website name. To do this, set the pattern query parameter to the desired regex pattern.

    Get suggested values to use for a segment parameter.

    The new API method API.getSuggestedValuesForSegment can now be used to get suggested values for a segment parameter. This method will return a list of the most seen values (in the last 60 days) for a certain segment parameter. So for browserCode, this would return the codes for the browsers most visitors used in the last 60 days.

    Use extra tracking query parameters with the JS tracker (such as ‘lat’ & ‘long’).

    We’ve added a new method to the JavaScript tracker named appendToTrackingUrl. You can use this method to add extra query parameters to a tracking request, like so :

    _paq.push(['appendToTrackingUrl', 'lat=X&amp;long=Y']);

    What we’re working on

    As we said above, Piwik v1.12 is the last in the 1.X series of releases. This means we are now officially working on Piwik 2.0.

    Piwik 2.0 will be a big release, to be sure, but it’s going to bring you more than just a couple new features and a bag of bug fixes. For Piwik 2.0 we will be revisiting the user needs and the ideals that originally prompted us to create Piwik in order to build our vision of the future of web analytics.

    Piwik 2.0 won’t just be a bigger, better web app, but a new platform for observing and analyzing the things that matter to you.

    Participate in Piwik

    Are you a talented developer or an experienced User Interface designer ? Or maybe you like to write documentation or are a marketing guru ?

    If you have some free time and if you want to contribute to one of the most awesome open source projects around, please get in touch with the Piwik team, or read this page to learn more…

    Summary

    For the full list of changes in Piwik 1.12 check out the Changelog.

    Thank you to the core developers, all the beta testers and users, our official supporters, the translators & everyone who reported bugs or feature requests. Also thank you to softwares we use, and the libraries we use.

    If you are a company and would like to help an important project like Piwik grow, please get in touch, it means a lot to us. You can also participate in the project

    –> if you like what you read, please tell your friends and colleagues or write on your website, blog, forums, stackoverflow, etc. <–

    Peace. Enjoy !

  • Decoding VP8 On A Sega Dreamcast

    20 février 2011, par Multimedia Mike — Sega Dreamcast, VP8

    I got Google’s libvpx VP8 codec library to compile and run on the Sega Dreamcast with its Hitachi/Renesas SH-4 200 MHz CPU. So give Google/On2 their due credit for writing portable software. I’m not sure how best to illustrate this so please accept this still photo depicting my testbench Dreamcast console driving video to my monitor :



    Why ? Because I wanted to try my hand at porting some existing software to this console and because I tend to be most comfortable working with assorted multimedia software components. This seemed like it would be a good exercise.

    You may have observed that the video is blue. Shortest, simplest answer : Pure laziness. Short, technical answer : Path of least resistance for getting through this exercise. Longer answer follows.

    Update : I did eventually realize that the Dreamcast can work with YUV textures. Read more in my followup post.

    Process and Pitfalls
    libvpx comes with a number of little utilities including decode_to_md5.c. The first order of business was porting over enough source files to make the VP8 decoder compile along with the MD5 testbench utility.

    Again, I used the KallistiOS (KOS) console RTOS (aside : I’m still working to get modern Linux kernels compiled for the Dreamcast). I started by configuring and compiling libvpx on a regular desktop Linux system. From there, I was able to modify a number of configuration options to make the build more amenable to the embedded RTOS.

    I had to create a few shim header files that mapped various functions related to threading and synchronization to their KOS equivalents. For example, KOS has a threading library cleverly named kthreads which is mostly compatible with the more common pthread library functions. KOS apparently also predates stdint.h, so I had to contrive a file with those basic types.

    So I got everything compiled and then uploaded the binary along with a small VP8 IVF test vector. Imagine my surprise when an MD5 sum came out of the serial console. Further, visualize my utter speechlessness when I noticed that the MD5 sum matched what my desktop platform produced. It worked !

    Almost. When I tried to decode all frames in a test vector, the program would invariably crash. The problem was that the file that manages motion compensation (reconinter.c) needs to define MUST_BE_ALIGNED which compiles byte-wise block copy functions. This is necessary for CPUs like the SH-4 which can’t load unaligned data. Apparently, even ARM CPUs these days can handle unaligned memory accesses which is why this isn’t a configure-time option.

    Showing The Work
    I completed the first testbench application which ran the MD5 test on all 17 official IVF test vectors. The SH-4/Dreamcast version aces the whole suite.

    However, this is a video game console, so I had better be able to show the decoded video. The Dreamcast is strictly RGB— forget about displaying YUV data directly. I could take the performance hit to convert YUV -> RGB. Or, I could just display the intensity information (Y plane) rendered on a random color scale (I chose blue) on an RGB565 texture (the DC’s graphics hardware can also do paletted textures but those need to be rearranged/twiddled/swizzled).

    Results
    So, can the Dreamcast decode VP8 video in realtime ? Sure ! Well, I really need to qualify. In the test depicted in the picture, it seems to be realtime (though I wasn’t enforcing proper frame timings, just decoding and displaying as quickly as possible). Obviously, I wasn’t bothering to properly convert YUV -> RGB. Plus, that Big Buck Bunny test vector clip is only 176x144. Obviously, no audio decoding either.

    So, realtime playback, with a little fine print.

    On the plus side, it’s trivial to get the Dreamcast video hardware to upscale that little blue image to fullscreen.

    I was able to tally the total milliseconds’ worth of wall clock time required to decode the 17 VP8 test vectors. As you can probably work out from this list, when I try to play a 320x240 video, things start to break down.

    1. Processed 29 176x144 frames in 987 milliseconds.
    2. Processed 49 176x144 frames in 1809 milliseconds.
    3. Processed 49 176x144 frames in 704 milliseconds.
    4. Processed 29 176x144 frames in 255 milliseconds.
    5. Processed 49 176x144 frames in 339 milliseconds.
    6. Processed 48 175x143 frames in 2446 milliseconds.
    7. Processed 29 176x144 frames in 432 milliseconds.
    8. Processed 2 1432x888 frames in 2060 milliseconds.
    9. Processed 49 176x144 frames in 1884 milliseconds.
    10. Processed 57 320x240 frames in 5792 milliseconds.
    11. Processed 29 176x144 frames in 989 milliseconds.
    12. Processed 29 176x144 frames in 740 milliseconds.
    13. Processed 29 176x144 frames in 839 milliseconds.
    14. Processed 49 175x143 frames in 2849 milliseconds.
    15. Processed 260 320x240 frames in 29719 milliseconds.
    16. Processed 29 176x144 frames in 962 milliseconds.
    17. Processed 29 176x144 frames in 933 milliseconds.
  • does php's popen command execute immediately or queue ?

    30 novembre 2013, par b747fp

    If I loop through a mysql query and run a popen on each row, it appears that the commands are only running 1 at a time. Is there some sort of "queue" i can access and force to process 3 or 4 at a time, or do i just have to wait ? this is for ffmpeg and at this rate it will take days to complete all these commands one by one...

       foreach($videos as $video){
               popen(&#39;ffmpeg -i ........&#39;,&#39;r&#39;);
       }