RoQ was first developed for the FMV-based adventure game The 11th hour and was later adopted by Id for the Quake III engine and derivative games.

RoQ operates in a YUV 4:2:0 space. However, it was developed for a game released in the late 1994/early 1995 timeframe. Back then, cutting edge video was 640×480 at 256 colors or maybe 64K colors. and it was not feasible to take a large video frame and convert the entire thing from YUV -> RGB 30, 24, or even 15 times per second. However, RoQ’s design solved some of these problems.

Continue reading →

Sorenson Video 1 (SVQ1) makes me sentimental. It had a lot to do with why I started multimedia hacking. Strange that it all seems so simple now.

SVQ1 is a stark contrast to our last subject, Cinepak. SVQ1 does not store its codebooks in the encoded video bitstream. Rather, the codebooks are a hardwired characteristic of the coding scheme. That’s actually a really good thing considering that the algorithm is a hierarchical multistage vector quantizer.

Continue reading →

Cinepak is a true classic among video codecs. It saw considerable use in the early days of FMV as it was easily encapsulated in both AVI and QuickTime files, the prevailing container formats in the early days of PC multimedia. It was also the standard FMV format on early CD-based consoles such as the Sega Saturn and Atari Jaguar.

Continue reading →

Someone was asking me about vector quantizer codecs recently. Sure, Wikipedia has the obligatory article. To its credit, the article is actually halfway useful these days (I seem to recall that it used to be a lot more impenetrable). It doesn’t help that the concept is identified by 2 terms that, by themselves, sound somewhat intimidating: ‘vector’ and ‘quantization’.

Anyway, he asked the right person about VQ codecs because I happen to love VQ codecs and can go on for days about them. In fact, I might do just that. I’ll start with a post about the theory and then describe specific examples in separate posts.

Continue reading →