Since I need some distraction from VGM-XVD formats, I decided to look at some simple game format and somehow my eyes turned to Fable. This is a point-and-click adventure from 1996 from a studio that made only this game. Overall it could’ve been better with a better beginning, no whiplash-inducing ending and no aliens in the premise so it does not resemble a bad imitation of Might and Magic series.
Anyway, the game contains three videos: 50-second logos+opening, 3-minute intro and 50-second ending (it may be different for North American release but I’ve not seen that version). And the compression employed there turned out to be interesting.
It looks like they took PCX RLE for the inspiration but they made it more complex: depending on top bits you can have run, skip or raw copy. And raw copy is where it gets interesting. During decoding of the whole video file the raw pixel sequences are added to the special buffer which can be used later to copy pixels from. This reminds me somewhat of VPx golden frame which could be updated in some versions with fresh decoded blocks and referenced even many frames later.
And here is why I like to look at those old formats—they sometimes offer an interesting coding approach while modern codecs seem to be made from the standard blocks.
Thanks for keeping alive the flame of researching impossibly obscure game multimedia formats. 🙂
Well, I got into this field because I was interested in both how compression works and how game resources are organised, sometimes I manage to combine both of those interests.