C64MP3 je novi demo za Commodore 64 koji je Pex 'Mahoney' Tufvesson uradio za ovogodišnji demo party "Datastorm 2010". Šestog Februara ove godine, C64 je najzad "propevao", i to celu acapella verziju pesme "Tom's Diner" od Suzanne Vega (otprilike puna 2 minuta) :)
Citat:The Commodore 64 c64mp3 replay routine uses all the tricks in the book,
in order to acheive the best sound quality possible:
* The sound buffer is calculated in the stack, and it wraps
* Jitter free sample playback, by using NMI IRQ vector pointing to $dd04
* 8-bit sample output by using SID test bit for resetting oscillators
* saving clock cycles by JMP $dd0c when exiting an NMI
* Pitch tables? Good for module playback, but worthless for human voices
* Dithering noise, to make quantization smoother
* Phase-aligned wavetables with extracted formants
* Full 8-bit interpolation between formants with 16 different volume ratios
* 16 volume levels for resulting audio output
* self-modifying code, of course
* critical code run in Zero Page
* ...while only ~15 assembly instructions per sample available
* ...and still cpu-time left for a demo!
