MPEGAud - MPEG Audio Encoder/Decoder
Version 1.0a8
by George Warner
04/27/95
warnergt@aloft.att.com

REQUIREMENTS:
Mac with 68020 or greater (and possibly FPU or PPC depending on version).

1. WHAT IT IS: MPEGAud is a Macintosh program which can encode and decode 
MPEG audio to/from AIFF files.

2. CURRENT FEATURES:
2a.  AppleEvents (including Drop Launch Support).  Simply drag your files to 
be processed on the MPEGAud icon.  They will be queued up and processed.  
This is a nice compensating feature for the lack of speed.  Queue up a bunch of  
files and let them process overnight.
Notes about the drop-launch support:
    2a1.  Supports both encoding and decoding.  Mix them up if you want.
    2a2.  Allows dragging file(s) onto the MPEGAud icon at any time.  If you are 
             already processing a batch of files, you can drag more onto the icon 
             and they will be added to the queue.
    2a3.  It will only decode files ending in ".MP2" or ".MPG" or files of types 
             'MPEG' or 'MPGA' (contact me if this list should include other file types).
             For the new output filename, it will truncate the ".MP2" or ".MPG" 
             extension (if it exists), and add the ".AIFF" extension and overwrite any 
             files in the folder with the new name.
    2a4.  It will only encode files ending with the extension ".AIFF" or files of 
             type 'AIFF' (contact me if this list should include other file types).  For 
             the new output filename, it will truncate the ".AIFF" extension (if it 
             exists), and add the ".MP2" extension and overwrite any files in the 
             folder with the new name.
2b.  Multi-Platform Support - Versions available for:
    2b1.  Power Macs.  Get the MPEGAud PPC version.
    2b2.  Macs with 68020 (or greater) and an FPU.  Get the MPEGAud FPU version.
    2b3.  Macs with 68020 (or greater) and no FPU.  Get the MPEGAud NoFPU version.
        Sorry, no 68000 version.
2c.  Decoded file information.  Hold down the Option key when selecting Decode 
from the File Menu.  More file information will be displayed alternately with the 
file name.
2d.  Secret feature under construction (don't tell anyone!).  Decode support for 
MPEG audio layer III.  Use at your own risk.  Send me your files and feedback.

2.  RELEASE INFORMATION: 
Release 1.0a8  04/28/95  Eighth alpha version.  Fixed problem reading 
resource data.  The most obvious symptom of this problem appeared when 
encoding with psychoacoustic model 1; the application would crash.

Release 1.0a7  02/13/95  Seventh alpha version.  Fixed compatibility 
problem with some data streams which had ancillary data that looked 
like a syncword.  Added AppleEvents.  Now you can just drag your input 
file onto the application icon.
Fixed memory allocation error in encoder.  Added ability to encode 
as well as decode by dragging input file onto application icon.  
Encoding parameters will be taken from the preferences file which 
was set during last manual encode (i.e. last encoding by selecting 
menu item).

Release 1.0a6	01/24/95  Sixth alpha version.  Switched to Metrowerks 
CodeWarrior (from Symantec Think C).
a. Now three flavors:
  MPEGAud PPC - Native PowerMac version.
  MPEGAud FPU - Version for 68020 (or greater) with FPU.
  MPEGAud NoFPU - Version for 68020 (or greater).
b. More accurately (i.e. correctly) tests for the presence of an FPU 
and for the presence of at least a 68020.
c. Current file name displayed.
d. More information available on files being decoded.
 
Release 1.0a5	01/15/95  Fifth alpha version.  Significant fixes.
a. Fixed memory initialization problems.  Problems occurred when 
more than one file was processed.
b. Some optimization.  Converted all floats to long doubles (which are supposed 
to be faster).  Using native floating point format.  Turned on optimizations.
c. More error checking.  Detects more bad ".MP2" files.  Also added code to 
correctly save already decoded audio when corrupt data is detected.
d. Fixed AIFF icons to be more "grabbable."
e. Now tests for necessary Mac parameters (e.g. FPU).
f. Made default extension on encoded files ".MP2".
g. Fixed thermometer to work correctly on second and subsequent files.
h. Disabled Layer II bitrate and mode combinations that are not allowed.

Release 1.0a4	01/11/95  Fourth alpha version.  Many new changes.  
New features:
a. Drop-Launch Support!  -  Take your files and drag them onto the MPEGAud icon.
Fixes since last release:
a. Overhauled memory management.
b. Fixed background processing.

Release 1.0a3	04/19/94  Third alpha version.  Fixed a significant bug which 
caused it to hang with a Type 4 error (divide by zero).  Data in table 
resources was not totally correct.  Cleaned up the user interface.
Release 1.0a2	04/17/94  Second alpha version.  Now allow it to decode 
types other than just 'MPEG' and 'MPGA'.
Release 1.0a1	04/16/94	First alpha version.  I wasn't going to make this 
generally available, but what the heck.


3.  PERFORMANCE: Yes, it's slow, but what do you want for nothing?  I already 
have plans for accelerating it with the DSP3210 in av Macs and I'm sure that 
there is plenty of room of optimization for regular Macs.  This will come 
in time.

4.  WHAT YOU CAN DO:  Send me your constructive criticisms and new ideas.  
I'm currently juggling a number of projects right now so finding time for 
this one is not easy.  The level of interest in this program will certainly 
affect its priority in my schedule.