PDA

View Full Version : WARNING DMC generates nonstandard wav files



Unregistered
09-22-2003, 07:43 AM
Greetings, I could not find an email on your website, I am a developer working on audio editing software, which so far works great for all our customers except one, who claims to have generated his wav file with dBpowerAMP Music Converter.
Upon close inspection of the header with a hex editing application, I have found it to be non-standard. Here's why:
The wav file specification explicitly states that in the field Subchunk1Size at byte offset 0x10 the value must be 0x10 for PCM files, instead of 0x12, which is what your software erroneously writes.
The problem is that you are including by default an optional 2-byte field at the end of the header, "ExtraParamSize" which should not exist for PCM wav files.
Since you are clearly indicating in the AudioFormat field at offset 0x14 that the wav is indeed in PCM format by having it contain the value 1, I believe this to be a flaw in your software and both me and my client would be grateful if you would fix it.
Thank you for your time.

JL

Spoon
09-22-2003, 05:21 PM
Previous version write a WAVEFORMATEX header, although you call it non-standard your software should just read the WAVEFORMAT part.

I can forward you some code from the MSDN which will allow your program to correctly read all wave files, not just hard codec PCM (sort of reminds me of Amiga programmers who would look at certain things at certain addresses, new bios updates would break said bad programs).

BTW the latest beta writes WAVEFORMAT, and WAVEFORMATEX for Compessed ACM or WAVEFORMATEXTENSIBLE.