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-------------------------------------------------------------------------------
MPEGAPlayer 2.45 (16-Aug-1997)
-------------------------------------------------------------------------------
Distribution Conditions
-----------------------
This program is copyright (c) 1995-97 by Stephane TAVENARD.
It may be distributed freely under the condition that no profit is
gained from its distribution, nor from any other program distributed
in the same package.
Permission is granted to distribute this package by Bulletin Board
systems or network sites, under the condition that no fee is charged
on downloading it.
All files that are part of this package have to be distributed
together and none of them may be changed in any way other than
archiving or crunching. The only exception to this rule are the
icons, including the tooltypes, which may be changed to accommodate
them to the rest of the disk it is distributed on.
This program is distibuted as giftware.
Disclamer
---------
This package is provided "as is" without warranty of any kind.
The author assumes no responsibility or liability whatsoever
for any damage or dataloss caused by using this package.
Introduction
------------
What is MPEG audio ?
It's a very efficient audio compression standard. Actually, there are 3 methods
of compression named Layer I, II & III. Layer III is more efficient than
Layer II and layer II is more efficient than layer I :) .
MPEG audio allow to compress a 16-bits PCM sound file from 1.2 to 32 times.
Why is it so hard to make a real time MPEG audio decoder ?
MPEG audio decoding requires a lot of arithmetic calculation, so a lot of CPU
power is required. Normally, MPEG audio decoding is made with help of a DSP.
History
-------
V1.0 11-Jun-1995 First release (not public)
V1.1 19-Jun-1995 Corrected minor bug in audio signal allocation
V1.11 09-Jul-1995 Asynchronous Config window & Screen locking bug corrected
V1.2 10-Sep-1995 Added mixing frequency for audio output
07-Feb-1996 68060 version not optimized
V1.3 01-Jul-1996 Fixed a bug in the check routine
Corrected old bug that kill my prog
V1.4 28-Dec-1996 Correct bug in Config save ! (very old bug...)
Now supports MPEG-2 Layer1&2
Now Scopes Genies works !
Added Volume/Balance/Faster/Slower/Prev/Next
Use Christian Buchner 14-bit calibrated audio
V1.41 17-Feb-1997 Added Audio buffer time config (1/4 sec to 2 secs)
Added High priority config
V1.42 27-Feb-1997 Added Boost Volume option in config
V2.00 05-May-1997 Major release (Player is now in 'C')
Added MPEG layer III
Improved multitasking
Added AHI (V4)
No more 8 bit output
New Configuration
V2.10 16-May-1997 Improved Audio manager (and fixed 'skipping' bug)
Fixed bugs in memory allocation
Audio Filter is not changed by player any more
V2.20 18-May-1997 Fixed bug in Audio reset
Improved MPEG Decoding (20% faster on 060)
V2.30 24-May-1997 Fixed bug that crashed player when start playing.
New Audiomanager (uses soft interrupts)
V2.35 29-May-1997 Fixed play/pause function (bug in V2.30)
Gain of 6% for Layer III decoding (on '060)
V2.40 16-Jul-1997 Enhanced Status Window (time bar now !)
Use Async I/O
Gain of 5% for Layer III decoding (on '060)
Separate setting for Layers I&II and Layer III
V2.45 16-Aug-1997 Fixed a bug in Audiomanager (AHI mode)
Fixed some bugs in windows show/hide
Description
-----------
This is a player for DeliTracker program (thanks to Peter Kunath and
Frank Riffel for this marvellous soundplayer). You need at least a
68020 CPU to use it ! This player can decode and play standard
MPEG audio bitstreams, layers I, II & III.
Audio output can be made whit my internal paula driver (14 bits)
or with AHI device (you need at least V4 of AHI)
How to use it ?
First, get a version of DeliTracker (best: get the latest version).
Then, copy the corect player file 'MPEGAPlayer.xxx'
in the DeliPlayer directory.
***** WARNING *****
THE FPU VERSIONS ARE NOW FULL FPU CODED, THEY PROVIDE BETTER
SOUND QUALITY, BUT THEY ARE SLOWER THAN NON FPU ONES.
***** WARNING *****
Last, start DeliTracker and try to load an MPEG Audio file:
You don't hear anything:
-> there's a bug ?
You hear a some sound broken with blanks:
-> Your CPU is not enough faster for the current options.
You hear a countinous sound (10 sec):
-> Ok, you've got a good CPU, try to find long MPEG file now.
Options
-------
In the player option window of DeliTracker, select Config button.
Then you can configure the MPEG decoder for mono and stereo files
separately (why ? because decoding time of stereo files is approx.
2x decoding time of mono files). Config. options are:
The decoding options are separated for MPEG Layers I & II and
Layer III.
Mono & Stereo file
~~~~~~~~~~~~~~~~~~
Qual (Quality): High, Medium, Low
~~~~~~~~~~~~~~
-> defines the decoding quality, and also the decoding speed.
Slow CPU users, select Low quality ...
F.Max (Freq Max): 4000..48000
~~~~~~~~~~~~~~~~
-> defines the maximum output decoding frequency.
If the frequency of the file to decode is greater than the 'Freq Max'
specified, the decoder divide by 2 or by 4 in order to have a
decoding frequency just bellow 'Freq Max'
Slow CPU users, set this value to 12000 (div by 4) or 24000 (div by 2)
For Fast CPU, you can set this to 48000 in order to never divide
output frequencies.
Note: 'Freq Max' allows better setting than the 'Frequency' selector
of the older releases.
Force mono:
~~~~~~~~~~
For stereo files, it's possible to play them in mono (save a lot of CPU time)
when selecting 'Force Mono'
Miscellaneous
~~~~~~~~~~~~~
Scopes:
~~~~~~
When disabled, the player don't make calculation for the scopes, so it can
save some usefull power on Slow CPU !
Status:
~~~~~~
When enabled, the status window is automatically opened when an mpeg audio
file starts to play.
Priority:
~~~~~~~~
Allows to set the player's priority from 0 (normal) to 19 (high).
Set it to 19 if you don't want to have audio 'holes' when using others
applications that need a lot of CPU.
A value of 3 is a good value for a player.
Buffer Time:
~~~~~~~~~~~
Specified the amount of decoded audio samples to keep in memory.
3 secs is a good value.
Audio
~~~~~
Enable AHI:
~~~~~~~~~~
If not checked, use the internal PAULA driver (use 14 bit calibrated audio output)
If checked, use AHI driver, you can then choose an audiomode by clicking on
'Get AHI Mode' ...
Mixing:
~~~~~~
If not checked, the audio output frequency is the same as the decoder frequency.
If checked, the audio frequency is specified by the 'Mix. freq' field.
Vol. Boost:
~~~~~~~~~~
Allows to boost the audio volume (100% correspond to normal volume).
Ok, everything is clear ? try it now !
Copyrights
----------
DeliTracker is Copyright © by Delirium Softdesign
AHI is © by Martin Blom
Thanks
------
Peter Kunath and Frank Riffel for DeliTracker !
Martin Blom for the marvellous AHI system !
Christian Buchner for his 14-bit audio calibrated.
Thanks to my friend, AMIGA, the best computer ever made.
/ /
/ /
/ /
\ \ / /
\ \/ /
\/\/
Stéphane TAVENARD (ANGERS/France)
E-Mail: tavenard@xiii.univ-angers.fr (it's my brother Raphael mail)
IRC: Tatav
Snail: if you want to send me gifts :^)
Stéphane TAVENARD
La Bezanière
49070 Saint Jean de Linières
FRANCE
Nota from Raphaël: Because my E-mail account is very very short, please tell me before
using an attachment :(