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• Tele-Arena Lives On

  25 février 2011, par Multimedia Mike — Game Hacking

  Readers know I have a peculiar interest in taking apart video games and that I would rather study a game’s inner workings than actually play it. I take an interest on others’ efforts in this same area. It’s still in my backlog to take a closer look at Clone2727’s body of work. But I wanted to highlight my friend’s work on re-implementing a game called Tele-Arena.

  
  
  

  Back In The Day
  As some of you are likely aware, there was a dark age of online communication that predated the era of widespread internet access. This was known as "The BBS Age". People dialed into these BBSes using modems that operated at abysmal transfer speeds and would communicate with other users, upload and download files, and play an occasional game.

  BBS software evolved and perhaps the ultimate (and final) evolution was Galacticomm’s MajorBBS (MBBS). There were assorted games that plugged into the MBBS, all rendered in glorious color ANSI graphics. One of the most famous of these games was Tele-Arena (TA). TA was a multiplayer fantasy-themed text adventure game. Perhaps you could think of it as World of Warcraft, only rendered as interactive fiction instead of a rich 3D landscape. (Disclaimer : I might not be qualified to make that comparison since I have never experienced WoW firsthand, though I did play TA on and off about 17 years ago).

  TA was often compared to multi-user dungeons — or MUDs — that were played by telneting into internet servers hosting games. Such comparisons were usually unfavorable as people who had experience with both TA and MUDs were sniffy elitists with internet access who thought they were sooooo much better than those filthy, BBS-dialing serfs.

  Sorry, didn’t mean to open old wounds.

  Modern Retelling of A Classic Tale
  Anyway, my friend Ron Kinney is perhaps the world’s biggest fan of TA. So much so that he has re-implemented the engine in Java under the project name Ether. He’s in a similar situation as the ScummVM project in that, while the independent, open source engine is fair game for redistribution, it would be questionable to redistribute the original data files. That’s why he created an AreaBuilder application that generates independent game data files.

  Ironically, you can also telnet into a server on which Ron hosts an instance of Tele-Arena (ironic in the sense that the internet/BBS conflict gets a little blurry).

  I hope that one day Ron will regale us with the strangest tales from the classic TA days. My personal favorite was "Wrath of a Sysop."

• Giving Thanks For VP8

  25 novembre 2010, par Multimedia Mike — VP8

  It’s the Thanksgiving holiday here in the United States. I guess that’s as good a reason as any to release a first cut of my VP8 encoder. In order to remind people that they shouldn’t expect phenomenal quality from it — and to discourage inexperienced people from trying to create useful videos with it — I have hardcoded the quantizers to their maximum settings. For those not skilled in the art, this is the setting that yields maximum compression and worst quality. When compressing the Big Buck Bunny logo image, the resulting file is only 2839 bytes but observe the reconstructed quality :

  
  
  It really just looks like a particularly stormy day in the forest.
  

  First VP8 File From An Independent Encoder
  I found a happy medium on the quantizer scale and encoded the first 30 seconds of Big Buck Bunny for your inspection. I guess this makes it the first VP8/WebM file from an independent encoder (using FFmpeg’s Matroska muxer as well).

  Download : bbb-360p-30sec-q40.webm ( 13 MBytes)

  I think the quality makes it look like it was digitized from an old VHS tape.

  For fun, here’s the version with the quantizer cranked to the max : bbb-360p-30sec-q127.webm ( 1.3 MBytes)

  Aside : I was going to encapsulate the video in this post using a bare HTML5 <video> tag for the benefit of the small browsing population who could view that (indeed, it works fine in Chrome). But that would be insane due to the fact that supporting browsers preload the video with no easy (read : without the help of JavaScript) method for overriding this unacceptable default.

  The Code
  I’m still trying to get over my fear of git. To that end, I have posted the code on Github :

  https://github.com/multimediamike/ffvp8enc

  I still don’t like you, git. But I’m sure we’ll find some way to make this work.

  Other required code changes in the basic FFmpeg tree :

  • Of course, copy vp8enc.c into libavcodec/
  • In libavcodec/allcodecs.c, ’REGISTER_DECODER (VP8, vp8);’ turns into ’REGISTER_ENCDEC (VP8, vp8);’
  • Add ’OBJS-$(CONFIG_VP8_ENCODER) += vp8enc.o’ to libavcodec/Makefile

  Further Work
  About the limitations and work yet to do :

  • it’s still intra-only, no interframes (which is where a lot of compression occurs)
  • no rate control or distortion optimization, obviously
  • no intra 4x4 coding (that’s close to working but didn’t my little T-day deadline)
  • no quantization control ; this should really be hooked up to the FFmpeg command line but I’m not sure how
  • encoder writes into a static-sized, 1/2 MB memory buffer ; this can overflow
  • code is a mess (what did you expect at this stage of the game ?)
  • lots and lots of other things, surely

• Docs for V2.97a.20111030

  31 octobre 2011, par Scott Schiller

  m doc/download/index.html m doc/index.html Docs for V2.97a.20111030