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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 (...)

  • Publier sur MédiaSpip

    13 juin 2013

    Puis-je poster des contenus à partir d’une tablette Ipad ?
    Oui, si votre Médiaspip installé est à la version 0.2 ou supérieure. Contacter au besoin l’administrateur de votre MédiaSpip pour le savoir

  • 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.

Sur d’autres sites (7176)

  • WebM Decoding Improvements in Google Chrome 6

    10 septembre 2010, par noreply@blogger.com (John Luther)

    Google Chrome 6 for Windows, Mac and Linux was released last week. We want to congratulate the Chrome team and thank them for their contributions to the WebM project.

    Making the web faster is a core goal of Chrome, and we are happy to report that across a set of test clips Chrome 6 decodes VP8 video significantly faster than the developer version that was released at our launch in May. On single-core Intel machines the average improvement is about 20% ; on multicore processors it ranges from 15% (two cores) to 50% (four cores). If you want to try it for yourself, get Chrome 6 and then follow our instructions for playing WebM videos on Youtube.

    We’ve made further decoding speed gains in Chrome 7 dev channel, and are working on better video rendering to further improve the WebM user experience.

  • Launch Leech and the History of WMV

    14 septembre 2010, par Multimedia Mike — General

    I was combing through my programming archives again and came across an old Perl script called launch-leech.pl. This was a private script I used to maintain for the benefit of myself and a few friends. See, there was this site called Launch.com (URL doesn’t seem to do anything as of this writing but here’s the Wikipedia page). Purchased by Yahoo ! in 2001, Launch still maintained their independent branding. They also carried a lot of music videos, of which I am a huge junkie. launch-leech.pl was the tool I used to download the videos. This was particularly useful since I stubbornly clung to dialup internet access until mid-2004 and it would have been impossible to stream video at any decent quality (though there were 56k streams, so like I said– not possible at any decent quality).



    Technically
    I followed Launch.com for many years. To be honest, I only “followed” in that I figured out where their “latest videos” URL lived and regularly polled it. Each video had either a 6-, 7-, or 8-digit unique ID that could be plugged into the launch-leech.pl script which would then have a conversation with the relevant servers, determine the correct streaming URL with the highest quality, then download and save the URL by handing it off to an external program (first ASFRecorder, though I later switched to mmsclient).

    At one point, I even wrote a crawler that compiled an offline database of all the videos, their IDs and their metadata. I never thought of anything interesting to do with it, though.



    Windows Media Legacy
    During these glory days of leeching, Launch.com streamed using Windows Media. I admit, it’s a bit of a blur now — the site might have used Real or QuickTime, but I was obviously most in tune with the WM side. I remember when I first found the site circa 2000-2001, the videos were in MS MPEG-4v3, and the high quality bitrate was 300 kbits/sec. Eventually, Launch.com would stream WMV7, WMV8, and finally WMV9, with bitrates up to 700 kbits/sec. However, they never broke free of the 320×240 encoding resolution, which was frustrating. When I wasn’t able to notice any substantial difference between 300 and 700 kbits/sec, I felt it might be time to put those extra bits to work on a resolution upgrade.

    At least they were nice enough to re-encode a number of old videos using better codecs and bitrates with each revision, thus prompting me to scan through the site collecting updated video IDs for download.



    Epilogue
    I don’t clearly remember when I stopped visiting Launch.com. Video-wise, the web has been a blur of Flash video ever since about 2006. Meanwhile, I spent a lot of time collecting a bunch of music videos in the first half of the decade only to find that pretty much every version of every music video made since the dawn of time is available on demand thanks to YouTube. I have found that this phenomenon manifests in many areas as internet technology marches on.

    The Real Entertainment
    The launch-leech.pl tool represents a recurring pattern for me. I derive as much — if not more — entertainment from creating programs like launch-leech.pl (and implicitly reverse engineering something in the process ; in this case, a website) as I do from the intended entertainment media itself. I seem to have this issue a lot with games, too.

    Is this an issue for anyone else ? Am I the only one who would rather play with the box that a shiny toy comes packaged in ?

  • Vedanti and Max Sound vs. Google

    14 août 2014, par Multimedia Mike — Legal/Ethical

    Vedanti Systems Limited (VSL) and Max Sound Coporation filed a lawsuit against Google recently. Ordinarily, I wouldn’t care about corporate legal battles. However, this one interests me because it’s multimedia-related. I’m curious to know how coding technology patents might hold up in a real court case.

    Here’s the most entertaining complaint in the lawsuit :

    Despite Google’s well-publicized Code of Conduct — “Don’t be Evil” — which it explains is “about doing the right thing,” “following the law,” and “acting honorably,” Google, in fact, has an established pattern of conduct which is the exact opposite of its claimed piety.

    I wonder if this is the first known case in which Google has been sued over its long-obsoleted “Don’t be evil” mantra ?

    Researching The Plaintiffs

    I think I made a mistake by assuming this lawsuit might have merit. My first order of business was to see what the plaintiff organizations have produced. I have a strong feeling that these might be run of the mill patent trolls.

    VSL currently has a blank web page. Further, the Wayback Machine only has pages reaching back to 2011. The earliest page lists these claims against a plain black background (I’ve highlighted some of the more boisterous claims and the passages that make it appear that Vedanti doesn’t actually produce anything but is strictly an IP organization) :

    The inventions key :
    The patent and software reduced any data content, without compressing, up to a 97% total reduction of the data which also produces a lossless result. This physics based invention is often called the Holy Grail.

    Vedanti Systems Intellectual Property
    Our strategic IP portfolio is granted in all of the world’s largest technology development and use countries. A major value indemnification of our licensee products is the early date of invention filing and subsequent Issue. Vedanti IP has an intrinsic 20 year patent protection and valuation in royalties and licensing. The original data transmission art has no prior art against it.

    Vedanti Systems invented among other firsts, The Slice and Partitioning of Macroblocks within a RGB Tri level region in a frame to select or not, the pixel.

    Vedanti Systems invention is used in nearly every wireless chipset and handset in the world

    Our original pixel selection system revolutionized wireless handset communications. An example of this system “Slice” and “Macroblock Partitioning” is used throughout Satellite channel expansion, Wireless partitioning, Telecom – Video Conferencing, Surveillance Cameras, and 2010 developing Media applications.

    Vedanti Systems is a Semiconductor based software, applications, and IP Continuations Intellectual Property company.

    Let’s move onto the other plaintiff, Max Sound. They have a significantly more substantive website. They also have an Android app named Spins HD Audio, which appears to be little more than a music player based on the screenshots.

    Max Sound also has a stock ticker symbol : MAXD. Something clicked into place when I looked up their ticker symbol : While worth only a few pennies, it was worth a few more pennies after this lawsuit was announced, which might be one of the motivations behind the lawsuit.

    Here’s a trick I learned when I was looking for a new tech job last year : When I first look at a company’s website and am trying to figure out what they really do, I head straight to their jobs/careers page. A lot of corporate websites have way too much blathering corporatese that can be tough to cut through. But when I see what mix of talent and specific skills they are hoping to hire, that gives me a much better portrait of what the company does.

    The reason I bring this up is because this tech company doesn’t seem to have jobs/careers page.

    The Lawsuit
    The core complaint centers around Patent 7974339 : Optimized data transmission system and method. It was filed in July 2004 (or possibly as early as January 2002), issued in July 2011, and assigned (purchased ?) by Vedanti in May 2012. The lawsuit alleges that nearly everything Google has ever produced (or, more accurately, purchased) leverages the patented technology.

    The patent itself has 5 drawings. If you’ve ever seen a multimedia codec patent, or any whitepaper on a multimedia codec, you’ve seen these graphs before. E.g., “Raw pixels come in here -> some analysis happens here -> more analysis happens over here -> entropy coding -> final bitstream”. The text of a patent document isn’t meant to be particularly useful. I’ve tried to understand this stuff before and it never goes well. Skimming the text, I just see a blur of the words data, transmission, pixel, and matrix.

    So I read the complaint to try to figure out what this is all about. To summarize the storyline as narrated by the lawsuit, some inventors were unhappy with the state of video compression in 2001 and endeavored to create something better. So they did, and called it the VSL codec. This codec is so far undocumented on the MultimediaWiki, so it probably has yet to be seen “in the wild”. Good luck finding hard technical data on it now since searches for “VSL codec” are overwhelmed by articles about this lawsuit. Also, the original codec probably wasn’t called VSL because VSL is apparently an IP organization formed much later.

    Then, the protagonists of the lawsuit patented the codec. Then, years later, Google wanted to purchase a video codec that they could open source and use to supplant H.264.

    The complaint goes on to allege that in 2010, Google specifically contacted VSL to possibly license or acquire this mysterious VSL technology. Google was allegedly allowed to study the technology, eventually decided not to continue discussions, and shipped back the proprietary materials.

    Here’s where things get weird. When Google shipped back the materials, they allegedly shipped back a bunch of Post-It notes. The notes are alleged to contain a ton of incriminating evidence. The lawsuit claims that the notes contained such tidbits as :

    • Google was concerned that its infringement could be considered “recklessness” (the standard applicable to willful infringement) ;
    • Google personnel should “try” to destroy incriminating emails ;
    • Google should consider a “design around” because it was facing a “risk of litigation.”

    Actually, given Google’s acquisition of On2, I can totally believe that last one (On2’s codecs have famously contained a lot of weirdness which is commonly suspected to be attributable to designing around known patents).

    Anyway, a lot of this case seems to hinge on the authenticity of these Post-It notes :

    “65. The Post-It notes are unequivocal evidence of Google’s knowledge of the ’339 Patent and infringement by Defendants”

    I wish I could find a stock photo of a stack of Post-It notes in an evidence bag.

    I’ve worked at big technology companies. Big tech companies these days are very diligent about indoctrinating employees about IP liability issues. The reason this Post-It situation strikes me as odd is because the alleged contents of the notes basically outline everything the corporate lawyers tell you NOT to do.

    Analysis
    I’m trying to determine what specific algorithms and coding techniques. I guess I was expecting to see a specific claim that, “Our patent outlines this specific coding technique and here is unequivocal proof that Google A) uses the same technique, and B) specifically did so after looking at our patent.” I didn’t find that (well, a bit of part B, c.f., the Post-It note debacle), but maybe that’s not how these patent lawsuits operate. I’ve never kept up before.

    Maybe it’s just a patent troll. Maybe it’s for the stock bump. I’m expecting to see pump-n-dump stock spam featuring the stock symbol MAXD anytime now.

    I’ve never been interested in following a lawsuit case carefully before. I suddenly find myself wondering if I can subscribe to the RSS feed for this case ? Too much to hope for. But I found this item through Pando and maybe they’ll stay on top of it.