Dear Sir/Madam: Recently, I take part in developing a mp3 decoder, and we come across a questios that is: How to test the mp3 LIBMAD decoder compliance with respect to the ISO/IEC 11172 international standard, which are stated in http://www.underbit.com/resources/mpeg/audio/compliance/.

To test the decoder compliance, our method are taken as follows: 1. we get a test case (layer 3 test bitstreams), which we got from the web ftp://ftp.fhg.de/pub/layer3/ at Fraunhofer Institut. The case consists of: compl.bit the test bitstream (10Hz-10kHz/-20dB sine sweep) mono, 48 kHz compl.hex reference output in 24bit ascii hex format (mono)

These two files are mp3 test bitstreams whice are designed to help verify that an mpeg decoder works properly.These conformance bitstreams are the official test bitstreams provided by the MPEG committee.

2. next we catch the audio output data by decoding the bitstream "compl.bit" with our player.

3. then compare this output with the reference output "compl.hex".

However we found the two output are totally different. I wonder if somebody are kindly enough to share us with what is your test method and test case to do the compliance test. Looking forward your response.

Best regards!

leon email:lizhan@amoi.com.cn