Atari Falcon DSP56001 MPEG Audio Layer II Decoder


      

Atari Falcon DSP56001 PRG/ACC MPEG Audio Layer II Decoder


A NoCrew DSP Laboratories Production MCMXCIX




About the program

The mp2 player is a stand-alone program available for the Atari Falcon
compatible series of computers. It is designed to decode MPEG audio layer
2 data streams.

Best of all, the program is free! You can download and use it as much as
you like. The program is distributed under GPL (Gnu General Public License).

News

Latest version is 0.995. The change from 0.994 is a new external clock
detection routine, generously provided by Denis Huguet (STGhost/SectorOne).
It supports both single and dual clocks. The new version also runs in
TT-RAM, if available. 

We are currently working on the new version of the player. Some of the
many new features include:


   Superior sound quality.  The annoying sound glitches found
       in earlier versions have been remedied.

The DSP code is optimized: it requires less memory and is alot
       faster compared to previous versions.  One can especially note
       that the frequency transformation algorithm now uses an IMFCT
       (Inverse Modified Fast Cosine Transform) technique instead
       of the much slower IMDCT (Inverse Modified Discrete Cosine
       Transform).

The player has been enhanced with Shoe, a
       Scheme-like language interpreter.  Normally, routines written in
       Shoe emulate the behaviour of the old system.  However, we have
       also made a special jukebox mode with play lists and similar features.

    In short, most of the decoder back-end and interactive controls
       are handled by Shoe.  This makes it possible to extend and customize
       the player in an infinite number of ways!  Also, a online Shoe
       console window can process statements in the language while the
       system is running.

The DSP decoder is equipped with RPC (Remote Procedure Call)
       functionality.  Using RPC, it is possible to configure and
       reconfigure the decoder in realtime while playing.  The RPC
       interface is primarily used for synchronizing the DSP with the
       CPU, however, it is very possible to allow for example digital
       volume adjustments and the like in the future.
       
The system call Dsp_ExecProg used for uploading the DSP code
       is replaced by the same routine found in the /dev/dsp56k
       device driver for Linux.  The reason is that the system call
       has the annoying feature of freezing from time to time.

The source code is clearer and more readable.


In addition:


   Mono support is planned.
We are looking at techniques for storing ancillary data about
       the music bundled with the data stream.  This can be used to
       store for example album titles and artist names.


Features

The player features many advanced functions. Among them are:


   Nice GEM user interface.
   
Can be run as an accessory or program.
   
Fast Forward.
   
Pause.
   
Song looping.
   
Time display (both played time and time left of song).
   
Find next song in the same directory.
   
Skip to next and previous song.
   
Configurable keyboard controls.
   
Jukebox mode with play lists.
   
Advanced programmable interface (Shoe console window).
   
Sync detection and recovery routines.
   
Automatic external clock detection.
   
Realtime frequency conversion when no external clock is available.
   
Handshaked DMA transfers, thus very low overall system load.


Screenshot

There is a screenshot available here.

Download

You can always find the latest version of the player at:
ftp://ftp.nocrew.org/pub/nocrew/tos/







*****

Copyright © 1998 By Fredrik Noring & Tomas Berndtsson.

Thanks to Magnus Lundström for finding an error in the webpage.

This page was last modified March 2002, 2002.