News

  Frontpage
  News archive
  News topics

Resources

  MSX Forum
  Articles
  Reviews
  Fair reports
  Photo shoots
  Fairs and meetings
  Polls
  Links
  Search

Software

Downloads
Webshop

MRC

  Who we are
  Join our team
  Donate
  Policies
  Contact us
  Link to Us
  Statistics

Lost your password?

Statistics

There are 115 guests and 4 MSX friends online

You are an anonymous user.

PCM Encoder 0.01

Friday, January 20, 2006 - 11:09
Submitted by: dvik
Topic: Development

Daniel Vik and Arturo Ragozini have just released a new version of PCM Encoder, a toolkit that allows you to encode WAV samples and playing them in crystal clear quality on MSX, using the standard PSG soundchip. Sample rates of 8kHz, 11.025kHz, 22.05kHz and even 44.1kHz are currently supported. The release package contains an encoder application (with source) and replayers so that you can use the resulting samples in your own productions.

You can listen to an example of a 44.1kHz sample played on a Philips VG-8020 MSX1 over here. For more information you can check out this forum thread or the extensive documentation included in the release package.

Relevant link: PCM Encoder

By Google

By snout on January 20 2006, 11:35

The results are simply amazing. Big, big, big thumbs up!!

By ARTRAG on January 20 2006, 11:43

"extensive documentation" ? This is a bit too much for 3 lines of description...

I would like to expand it in order to describe the interpolation, the oversampling
and many other parameters that can be usefull for getting the best results.
Probably also the rompack option should be improved, allowing different pagesize,
as, using ram pagemappers, you could need 16Kb chunks.

By ARTRAG on January 20 2006, 11:51

Actually ANY sample rate is supported by the encoder, provided that you are able to write your
own replayer.
Input your CPU frequency and the Tcycles of your system (MSX or spectrum or whatever you have that uses a PSG compatible with the chip AY-3-8910 or YM-2149) and you'll get the encoded results.

By POISONIC on January 20 2006, 17:03

WOW amazing it beats the Simple player on the printerport in one row exelent quality

wel done !

By ARTRAG on January 20 2006, 18:11

It is the BEST quality you can achieve on the PSG, in the very literal sense, as Viterbi optimisation finds the BEST sequence of PSG levels to reproduce your wav file

By msd on January 20 2006, 18:37

Are there more examples?

By ARTRAG on January 22 2006, 11:18

Actually I was wrong, the PSG replayer CAN IMPROVE even MORE !!

If the replayer can choice the channel to modify at any time, instead of using a fixed round-robin scheme (as now happens), the result should be free on any static noise.

The problem is that the Viterbi optimisation has to deal with a 16x16x16=4092 state machine where each state has 16*3=48 inputs !!

It is a cumbersome Viterbi optimisation and the required memory could be huge, moreover the data should store both the channel level (4bits) and the channel number (2 bits more per level!), so RLE packing on nibbles is no more possible.

Nevertheless, for the sake of science

, it if worth trying this new way, stay tuned…

By ARTRAG on January 25 2006, 10:03

I can claim that the definitive PSG limit has been achieved.
The new encoder provides 43dB of SNR …

at the cost of 3 bytes per sample

Stay tuned for the new C pcmenc.exe version!!