The displayed info in AW > Tag > Format is probably accurate. It shows information directly from the file.
The "Compression" library field can be wrong or empty without causing any changes to the program behavior. It is only informational.
Here is my post from the 12.0.113 thread:
MP2 audio filesMC's internal MPEG 1 Layer 2/3 decoder can handle these perfectly fine including tagging, but the ".mp2" extension (MPEG 1 Layer 2 format) is not correctly associated with MC's decoder.
If I manually change the ".mp2" extension to ".mp3" before importing MC handles the file correctly.
BillT has encountered the same problem:
http://yabb.jriver.com/interact/index.php?topic=31610.msg217257#msg217257Format info from a test file (filename: MP2 Test File.mp3)
MPEG-1 Layer 2
384 Kbit CBR
44.1 Khz Stereo
Copyrighted: No
Original: No
Protected by CRC: No
Gapless: No
ID3v1 Tag: (128 bytes)
Name: MP2 Test File
Artist:
Album:
Year:
Comment:
Track #: 0
Genre: undefined (255)
ID3v2.3 Tag: (533 bytes)
TIT2 (Title): MP2 Test File
TBPM (BPM (beats per min..): 100
COMM (Comments):
COMM (Tool Name): Media Center
COMM (Tool Version): 12.0.113
COMM (Peak Level): 0,96481
COMM (Replay Gain): -2,7494800000000001
COMM (Intensity): 1
Actually, all MPEG extensions should be checked. I have already done some of the needed ground research for you:
Quote from: Alex B on Sat 28.01.2006, 01:34MC has currently these MPEG file associations (besides the MP3 and MP4 variants):
mpa, mpga, mp2, mpeg, mpg, m1v, mpv, mpe, m2v
I have Steinberg's Wavelab 5 (a pro audio editor). It has an MPEG-1 Layer 2 encoder.
The offered file extension options are: mp2, mpa, mpg, mus
I remember now that I have previously changed the Media Type of my MP2 audio files because MC imported them as video. Afterall, I think the best system would be this:
mpg, mpeg, m1v, m2v, mpe, mpv, m2p, mpv2, mp2v, mpeg2 => Video
mp2, mpa, mpga, mp2a => Audio (use the internal MPEG audio decoder)
mp1 => Audio (I don't have any files in Layer 1 format, so I don't know if these work)
"mus" is used by the well-known Finale notation software for its proprietary format and I have never seen a .mus MPEG audio file so I guess it is not needed.
EDIT: Added m2p, it is used by Canopus for MPEG2 videos.
EDIT2: Added more extensions. The oldest MPEG-1 layer 1 audio format uses mp1. Sometimes the mp2a (MPEG-1 layer 2 audio), mpv2, mp2v and mpeg2 (MPEG-2 video) extensions are used too.