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• Who Invented FLIC ?

  26 mai 2011, par Multimedia Mike — Multimedia History

  I have been reading through “All Your Base Are Belong To Us : How 50 Years of Video Games Conquered Pop Culture” by Harold Goldberg. Despite the title, Zero Wing has yet to be mentioned (I’m about halfway done).

  
  
  

  I just made it through the chapter describing early breakthrough CD-ROM games, including Myst, The 7th Guest, and The 11th Hour. Some interesting tidbits :

  The 7th Guest
  Of course, Graeme Devine created a new FMV format (called VDX, documented here) for The 7th Guest. The player was apparently called PLAY and the book claims that Autodesk was so impressed by the technology that it licensed the player for use in its own products. When I think of an Autodesk multimedia format, I think of FLIC. The VDX coding format doesn’t look too much like FLIC, per my reading.

  Here’s the relevant passage (pp 118-119) :

  Devine began working on creating software within the CD-ROM disk that would play full-motion video. Within days he had a robust but small ninety-kilobyte player called PLAY that was so good, it was licensed by Autodesk, the makers of the best 3-D animation program at the time. Then Devine figured out a way to compress the huge video files so that they would easily fit on two CD-ROMs.

  Googling for “autodesk trilobyte play program” (Trilobyte was the company behind 7th Guest) led me to this readme file for a program called PLAY73 (hosted at Jason Scott’s massive CD-ROM archive, and it’s on a disc that, incidentally, I donated to the archive ; so, let’s here it for Jason’s tireless archival efforts ! And for Google’s remarkable indexing prowess). The file — dated September 10, 1991 — mentions that it’s a FLICK player, copyright Trilobyte software.

  
  
  

  However, it also mentions being a Groovie Player. Based on ScummVM’s reimplementation of the VDX format, Groovie might refer to the engine behind The 7th Guest.

  So now I’m really interested : Did Graeme Devine create the FLIC file format ? Multimedia nerds want to know !

  I guess not. Thanks to Jim Leonard for digging up this item : “I developed the flic file format for the Autodesk Animator.” Jim Kent, Dr. Dobbs Magazine, March 1993.

  The PLAY73 changelog reveals something from the bad old days of DOS/PC programming : The necessity of writing graphics drivers for 1/2 dozen different video adapters. The PLAY73 readme file also has some vintage contact address for Graeme Devine ; remember when addresses looked like these ?

  If you have any comments, please send them to :
  	Compuserve : 72330,3276
  	Genie : G.DEVINE
  	Internet : 72330,3276@compuserve.com
  

  The 11th Hour
  The book didn’t really add anything I didn’t already know regarding the compression format (RoQ) used in 11th Hour. I already knew how hard Devine worked at it. This book took pains to emphasize the emotional toll taken on the format’s creator.

  I wonder if he would be comforted to know that, more than 15 years later, people are still finding ways to use the format.

• Cracking Aztec Game Audio

  7 juin 2011, par Multimedia Mike — Game Hacking

  Here’s a mild multimedia-related reverse engineering challenge for you. It’s pretty straightforward for those skilled in the art.

  The Setup
  One side effect of running this ridiculously niche interest blog at the intersection of multimedia, reverse engineering, and game hacking is that people occasionally contact me for assistance on those very matters. So it was when one of my MobyGames peers asked if I can help to extract some music from a game called Aztec Wars. The game consists of 2 discs, each with a music.xbe file that contains multiple tunes and is hundreds of megabytes large.

  
  
  

  That’s all the data I received from the first email. At first I’m wondering what makes people think I have some magical insight into cracking these formats with such little information. Ordinarily, I would need to have the entire data file to work with and possibly the game binaries. But I didn’t want to ask him to upload hundreds of megabytes of data and I didn’t feel like downloading it ; commitment issues and all.

  But then I gathered a little confidence and remembered that the .xbe files are probably just Game Resource Archive Formats (GRAF) which are, traditionally, absurdly simple. I asked my colleague to send me a hexdump of the first kilobyte of one of the .xbe GRAFs ('hexdump -C -n 1024 music.xbe > file') as well as the total file size of the GRAF.

  The Hexdump
  The first music.xbe file is 192817376 bytes large. These are the first 1024 144 bytes (more than enough) :

  00000000  01 00 00 00 60 04 00 00  14 00 00 00 01 00 00 00  |....`...........|
  00000010  0d 00 00 00 48 00 00 00  94 39 63 01 1c a4 21 03  |....H....9c..¤ !.|
  00000020  7a d2 54 04 04 28 ad 05  d8 88 fd 06 d8 88 fd 06  |zÒT..(­.Ø.ý.Ø.ý.|
  00000030  2a 6e 46 08 2a 6e 46 08  2a 6e 46 08 2a 6e 46 08  |*nF.*nF.*nF.*nF.|
  00000040  50 13 2f 0a e0 28 7e 0b  52 49 46 46 44 39 63 01  |P./.à( .RIFFD9c.|
  00000050  57 41 56 45 66 6d 74 20  10 00 00 00 01 00 02 00  |WAVEfmt ........|
  00000060  44 ac 00 00 10 b1 02 00  04 00 10 00 64 61 74 61  |D¬...±......data|
  00000070  fc 13 63 01 00 00 00 00  00 00 00 00 00 00 00 00  |ü.c.............|
  00000080  00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00  |................|
  

  The Challenge
  Armed with only the information in the foregoing section, figure out a method for extracting all the audio files in that file and advise on their playback/conversion. Ideally, this method should require minimal effort from both you and the person on the other end of the conversation.

  The Resolution
  The reason I ask is because I came up with a solution but knew, deep down, that there must be a slightly easier way. How would you solve this ?

  The music files in question are now preserved on YouTube (until they see fit to remove them for one reason or another).

• parsing different ffmpeg -i output

  11 août 2012, par Jizbo Jonez

  I have a bit of code that gets a video files duration, width, height and framerate which works fine for some videos -

  $output = `ffmpeg -i /var/thismovie.avi`;
  
  preg_match('/Duration: (.*?),.*?Video:.*?0x.*?([0-9]+)x([[0-9]+).*?([0-9]+) fps/i'
  
  ,$output , $result);

  The problem is there are other videos that give a slightly different output information, for example the above code works with this output -

  Input #0, avi, from '/var/www/vhosts/thissite.com/httpdocs/video1.avi':
  
  Duration: 00:00:10.76, start: 0.000000, bitrate: 5180 kb/s
  
  Stream #0:0: Video: h264 (High) (H264 / 0x34363248), yuv420p, 1280x720 [SAR 1:1 DAR 16:9], 25 fps, 25 tbr, 25 tbn, 50 tbc
  
  Stream #0:1: Audio: ac3 ([0] [0][0] / 0x2000), 48000 Hz, stereo, s16, 128 kb/s

  but another video gives this info and will not give any results when used with the above code -

  Input #0, avi, from '/var/www/vhosts/thissite.com/httpdocs/video2.avi':
  
  Duration: 00:00:05.68, start: 0.000000, bitrate: 887 kb/s
  
  Stream #0:0: Video: mpeg4 (Advanced Simple Profile) (XVID / 0x44495658), yuv420p, 640x272 [SAR 1:1 DAR 40:17], 25 tbr, 25 tbn, 25 tbc
  
  Stream #0:1: Audio: mp3 (U[0][0][0] / 0x0055), 48000 Hz, stereo, s16, 128 kb/s

  The difference between the two outputs is in the Stream #0:0 part. The fist output shows 7 different pieces of information separated by a comma, the last output only shows 6 bits. The missing piece of info in the last output is the frame rate (fps) but apparently I can use the value for tbr instead.

  So my question is, how can I modify the code I am using to cover both types of outputs ?