home *** CD-ROM | disk | FTP | other *** search
Text File | 1995-01-23 | 4.7 KB | 101 lines | [TEXT/ttxt] |
- MPEGAud - MPEG Audio Encoder/Decoder
- Version 1.0a6
- by George Warner
- 01/24/95
- warnergt@aloft.att.com
-
- REQUIREMENTS:
- Mac with 68020 or greater (and possibly FPU depending on version).
-
- 1. WHAT IT IS: MPEGAud is a Macintosh program which can encode and decode
- MPEG audio to/from AIFF files.
-
- 2. RELEASE INFORMATION:
- Release 1.0a6 01/24/95 Sixth alpha version. Switched to Metrowerks
- CodeWarrior (from Symantec Think C). Now able to create a native PPC
- version. Yes, CodeWarrior is as great as everyone says (I was skeptical).
- 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).
- What? You only have a 68000? Don't even bother me for a 68000 version.
- 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. Hold down option
- key when selecting "Decode." Input file information will be alternately
- displayed with the file name.
- e. Drop-Launch Support does not work with PPC version. This code is
- still under construction. It will become available when I get
- AppleEvents fully working.
-
- Release 1.0a5 01/15/95 Fifth alpha version. Significant fixes.
- a. Fixed memory initialization problems. This was a result of the major
- memory management overhaul in the last release. 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 (and you thought my
- code had all the problems!). 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 MPEG audio files and drag them onto the
- MPEGAud icon. MPEGAud will launch, decode them into AIFF files, and quit.
- Drag a dozen MPEG audio files on MPEGAud and let them decode on you Mac
- overnight. This is a nice compensating feature for the lack of speed.
- Notes about the drop-launch support:
- It only supports decoding (launch app normal way for encoding).
- 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 a new filename, it will truncate the ".MP2" or ".MPG" extension, add the ".AIFF"
- extension and overwrite any files in the folder with the new name.
-
- Fixes since last release:
- a. Overhauled memory management.
- b. Fixed background processing.
-
- New features that didn't quite make it:
- a. AppleEvents: Almost all of the code is there, but it doesn't work.
- b. MPEG audio layer 3 support. This is another case where much of the code is
- written but it just isn't quite there. This is not a rainy day project, but a
- rainy week project. I don't expect to get it working soon.
-
- Feature being phased out:
- a. Support for PCM audio. It really is easier supporting only one uncompressed
- data format, so AIFF will be the one. Email me with any arguments for maintaining
- PCM support.
-
- 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. Also, cleaned up the user interface a
- little and added a progress thermometer to the decode to complement
- the encode thermometer.
- 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. I know that there are some memory
- management issues but it seems pretty solid.
-
-
- 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. FUTURE CAPABILITIES: Although it is not yet working, MPEGAud already
- contains some code for supporting Apple Events.
-
- 5. 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.
-
-