pouët.net

Use a real c64 with newsid (8580) or alternatively a c64 emulator such as Vice (With Resid active - 8580) or Micro64. Audio issues on other emulators.

It does have autodetect however and support for the Digimax cartridge for higher quality. Ideally use a real c64 to get the proper strobing effects :-)

Ignore the GFX, There was limited space left on the disk, this is a proof of concept.

The SSDPCM-MP was previously introduced in one of my Amiga demo's here

http://www.pouet.net/prod.php?which=65976

It is exactly the same method (only at a lower sampling rate)

Optimal dual step sizes are chosen for a given small chunk area of samples and these are quantised together with the bit patterns. They are recreated by addition and subtraction using the chosen step sizes.

As there are different step sizes for each given chunk, The audio is recreated rather accurately.

In order to process all this data in realtime on a C64, i have used codetables to optimally decode bitpatterns directly which gives a considerable speedup.

The animation is also 200 frames using VQ and then converted to 2x2 tiles for further packrate and then tile definitions delta encoded. All this has to be done in reverse (and in 16fps in this demo)

All the above using 90% cpu time is too much, hence had to be optimised to overall use far less (60-70% or so on average) in order to allow the loader to be able to have time to load the data.

In regards to sequence based loading. There are four slots and the program will load the relevant packed sample to one of these slots while decoding a sequence from another. This is continued with the data being loaded into the relevant slots and played back.