Son Shu Shi


As some may have noticed, the Amiga game “Son Shu Shi” how now been preserved with the help of Patrick Tamine (a friend of the author of the game at the time), Adrian Simpson of HOL and Codetapper of HOL/WHDLoad.

Unfortunately, the only remaining disks were no longer in good condition. So we had to reconstruct them from the corrupt data by finding out exactly what went wrong.

The problem with the game’s decrunching algorithm is that it is not easy to tell if the data is actually correct or not, it just keeps uncompressing the stream of data until it hits the end. The only way to verify it has been done correctly is to check if all the compressed source data has been “used up”.

Luckily there is one way to know the data has been uncompressed correctly, and that is by making use of a particular file present in the data. We actually expected many more variables to be involved, but by taking many different indicative factors into account, we could narrow down the result to only one possibility.

Our fix is completely derived from the encoding rules, the misrepresented data and the checksum.