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  • Websites made ​​with MediaSPIP

    2 mai 2011, par

    This page lists some websites based on MediaSPIP.

  • Possibilité de déploiement en ferme

    12 avril 2011, par

    MediaSPIP peut être installé comme une ferme, avec un seul "noyau" hébergé sur un serveur dédié et utilisé par une multitude de sites différents.
    Cela permet, par exemple : de pouvoir partager les frais de mise en œuvre entre plusieurs projets / individus ; de pouvoir déployer rapidement une multitude de sites uniques ; d’éviter d’avoir à mettre l’ensemble des créations dans un fourre-tout numérique comme c’est le cas pour les grandes plate-formes tout public disséminées sur le (...)

  • Ajouter des informations spécifiques aux utilisateurs et autres modifications de comportement liées aux auteurs

    12 avril 2011, par

    La manière la plus simple d’ajouter des informations aux auteurs est d’installer le plugin Inscription3. Il permet également de modifier certains comportements liés aux utilisateurs (référez-vous à sa documentation pour plus d’informations).
    Il est également possible d’ajouter des champs aux auteurs en installant les plugins champs extras 2 et Interface pour champs extras.

Sur d’autres sites (9490)

  • Museum of Multimedia Software, Part 2

    16 août 2010, par Multimedia Mike — Software Museum

    This installment includes a bunch of old, discontinued Adobe software as well as some Flash-related mutlimedia software.

    Screen Time for Flash Screen Saver Factory
    "Create High Impact Screen Savers Using Macromedia Flash."



    Requirements include Windows 3.1, 95 or NT 3.5.1. A 486 computer is required to play the resulting screensavers which are Flash projectors using Macromedia Flash 3.0.

    Monster Interactive Instant GUI 2
    Create eye-popping GUIs more easily for use in Flash. Usability experts would argue that this is not a good thing.



    Adobe Dimensions 3.0
    "The Easy Yet Powerful 3D Rendering Tool." This software was end-of-life’d in late 2004-early 2005 (depending on region).



    Adobe ImageStyler
    "Instantly add style to your Web site." Wikipedia claims that this product was sold from 1998 to 2000 when it was superseded by Adobe LiveMotion (see below).



    Google is able to excavate a link to the Latin American site for Adobe ImageStyler, a page that doesn’t seem to be replicated in any other language.

    Adobe LiveMotion
    "Professional Web graphics and animation." This is version 1, where the last version was #2, released in 2002.



    Adobe Streamline 4.0
    "The most powerful way to convert images into line art." This was discontinued in mid-2005.



    Adobe SuperATM
    "The magic that maintains the look of your documents." This is the oldest item in my collection. A close examination of the back of the box reveals an old Adobe logo. The latest copyright date on the box is 1992.



  • Revision 49930 : Icone de l’extension Porte Plume tiree de FatCow Retro ...

    24 juillet 2011, par cedric@… — Log

    Icone de l’extension Porte Plume tiree de FatCow ? Retro  http://www.spip-contrib.net/Icones-FatCowRetro

  • The 11th Hour RoQ Variation

    12 avril 2012, par Multimedia Mike — Game Hacking, dreamroq, Reverse Engineering, roq, Vector Quantization

    I have been looking at the RoQ file format almost as long as I have been doing practical multimedia hacking. However, I have never figured out how the RoQ format works on The 11th Hour, which was the game for which the RoQ format was initially developed. When I procured the game years ago, I remember finding what appeared to be RoQ files and shoving them through the open source decoders but not getting the right images out.

    I decided to dust off that old copy of The 11th Hour and have another go at it.



    Baseline
    The game consists of 4 CD-ROMs. Each disc has a media/ directory that has a series of files bearing the extension .gjd, likely the initials of one Graeme J. Devine. These are resource files which are merely headerless concatenations of other files. Thus, at first glance, one file might appear to be a single RoQ file. So that’s the source of some of the difficulty : Sending an apparent RoQ .gjd file through a RoQ player will often cause the program to complain when it encounters the header of another RoQ file.

    I have uploaded some samples to the usual place.

    However, even the frames that a player can decode (before encountering a file boundary within the resource file) look wrong.

    Investigating Codebooks Using dreamroq
    I wrote dreamroq last year– an independent RoQ playback library targeted towards embedded systems. I aimed it at a gjd file and quickly hit a codebook error.

    RoQ is a vector quantizer video codec that maintains a codebook of 256 2×2 pixel vectors. In the Quake III and later RoQ files, these are transported using a YUV 4:2:0 colorspace– 4 Y samples, a U sample, and a V sample to represent 4 pixels. This totals 6 bytes per vector. A RoQ codebook chunk contains a field that indicates the number of 2×2 vectors as well as the number of 4×4 vectors. The latter vectors are each comprised of 4 2×2 vectors.

    Thus, the total size of a codebook chunk ought to be (# of 2×2 vectors) * 6 + (# of 4×4 vectors) * 4.

    However, this is not the case with The 11th Hour RoQ files.

    Longer Codebooks And Mystery Colorspace
    Juggling the numbers for a few of the codebook chunks, I empirically determined that the 2×2 vectors are represented by 10 bytes instead of 6. Now I need to determine what exactly these 10 bytes represent.

    I should note that I suspect that everything else about these files lines up with successive generations of the format. For example if a file has 640×320 resolution, that amounts to 40×20 macroblocks. dreamroq iterates through 40×20 8×8 blocks and precisely exhausts the VQ bitstream. So that all looks valid. I’m just puzzled on the codebook format.

    Here is an example codebook dump :

    ID 0x1002, len = 0x0000014C, args = 0x1C0D
      0 : 00 00 00 00 00 00 00 00 80 80
      1 : 08 07 00 00 1F 5B 00 00 7E 81
      2 : 00 00 15 0F 00 00 40 3B 7F 84
      3 : 00 00 00 00 3A 5F 18 13 7E 84
      4 : 00 00 00 00 3B 63 1B 17 7E 85
      5 : 18 13 00 00 3C 63 00 00 7E 88
      6 : 00 00 00 00 00 00 59 3B 7F 81
      7 : 00 00 56 23 00 00 61 2B 80 80
      8 : 00 00 2F 13 00 00 79 63 81 83
      9 : 00 00 00 00 5E 3F AC 9B 7E 81
      10 : 1B 17 00 00 B6 EF 77 AB 7E 85
      11 : 2E 43 00 00 C1 F7 75 AF 7D 88
      12 : 6A AB 28 5F B6 B3 8C B3 80 8A
      13 : 86 BF 0A 03 D5 FF 3A 5F 7C 8C
      14 : 00 00 9E 6B AB 97 F5 EF 7F 80
      15 : 86 73 C8 CB B6 B7 B7 B7 85 8B
      16 : 31 17 84 6B E7 EF FF FF 7E 81
      17 : 79 AF 3B 5F FC FF E2 FF 7D 87
      18 : DC FF AE EF B3 B3 B8 B3 85 8B
      19 : EF FF F5 FF BA B7 B6 B7 88 8B
      20 : F8 FF F7 FF B3 B7 B7 B7 88 8B
      21 : FB FF FB FF B8 B3 B4 B3 85 88
      22 : F7 FF F7 FF B7 B7 B9 B7 87 8B
      23 : FD FF FE FF B9 B7 BB B7 85 8A
      24 : E4 FF B7 EF FF FF FF FF 7F 83
      25 : FF FF AC EB FF FF FC FF 7F 83
      26 : CC C7 F7 FF FF FF FF FF 7F 81
      27 : FF FF FE FF FF FF FF FF 80 80
    

    Note that 0x14C (the chunk size) = 332, 0x1C and 0x0D (the chunk arguments — count of 2×2 and 4×4 vectors, respectively) are 28 and 13. 28 * 10 + 13 * 4 = 332, so the numbers check out.

    Do you see any patterns in the codebook ? Here are some things I tried :

    • Treating the last 2 bytes as U & V and treating the first 4 as the 4 Y samples :


    • Treating the last 2 bytes as U & V and treating the first 8 as 4 16-bit little-endian Y samples :


    • Disregarding the final 2 bytes and treating the first 8 bytes as 4 RGB565 pixels (both little- and big-endian, respectively, shown here) :


    • Based on the type of data I’m seeing in these movies (which appears to be intended as overlays), I figured that some of these bits might indicate transparency ; here is 15-bit big-endian RGB which disregards the top bit of each pixel :


    These images are taken from the uploaded sample bdpuz.gjd, apparently a component of the puzzle represented in this screenshot.

    Unseen Types
    It has long been rumored that early RoQ files could contain JPEG images. I finally found one such specimen. One of the files bundled early in the uploaded fhpuz.gjd sample contains a JPEG frame. It’s a standard JFIF file and can easily be decoded after separating the bytes from the resource using ‘dd’. JPEGs serve as intraframes in the coding scheme, with successive RoQ frames moving objects on top.

    However, a new chunk type showed up as well, one identified by 0×1030. I have never encountered this type. Where could I possibly find data about this ? Fortunately, iD Games recently posted all of their open sourced games at Github. Reading through the code for their official RoQ decoder, I see that this is called a RoQ_PACKET. The name and the code behind it are both supremely unhelpful. The code is basically a no-op. The payloads of the various RoQ_PACKETs from one sample are observed to be either 8784, 14752, or 14760 bytes in length. It’s very likely that this serves the same purpose as the JPEG intraframes.

    Other Tidbits
    I read through the readme.txt on the first game disc and found this nugget :

            g)      Animations displayed normally or in SPOOKY MODE
    

    SPOOKY MODE is blue-tinted grayscale with color cursors, puzzle
    and game pieces. It is the preferred display setting of the
    developers at Trilobyte. Just for fun, try out the SPOOKY
    MODE.

    The MobyGames screenshot page has a number of screenshots labeled as being captured in spooky mode. Color tricks ?

    Meanwhile, another twist arose as I kept tweaking dreamroq to deal with more RoQ weirdness : After modifying my dreamroq code to handle these 10-byte vectors, it eventually chokes on another codebook. These codebooks happen to have 6-byte vectors again ! Fortunately, I was already working on a scheme to automatically detect which codebook is in play (plugging the numbers into a formula and seeing which vector size checks out).