Ah, yes I had that issue as well... output was big endian... using COOL EDIT you can view little or big endian PCM. If that doesnt work... I had to write a routine to write out samples the other way around... using fwrite(). SHARC embedded processors have some quarks with regular C code.... it isnt exactly "portable" as one might think. Whatever your platform is, my adivce is to get a HEX viewer that allows you to see exactly what you are writing out to a file... and compare that output to what you should be getting (maybe make a windows implementation of minimad to compare to, as I did). Its a battle but it makes sense when you can see the data. Good luck.
Matt
-----Original Message----- From: mad-dev-bounces@lists.mars.org [mailto:mad-dev-bounces@lists.mars.org]On Behalf Of Nigel Sinfield Sent: 10-Nov-05 11:35 AM To: 'Joe Drew'; feiye Cc: mad-dev@lists.mars.org Subject: RE: [mad-dev] help:loud noise in the madplay
When I had this problem it turned out to be an 'endian' issue. mad output the samples one way, but the audio hardware required the other.
-----Original Message----- On Nov 8, 2005, at 1:12 AM, feiye wrote:
I have transplant madplay to embedded linux2.4.18. When I play the mp3,it has a loud noise in the music. Has anybody met this before? Can anybody help?
I remember problems very much like this when I was first creating mpg321, and IIRC the problem was a 'signed' issue. Perhaps 'char' is signed on your platform, and your output needs unsigned?
I do remember the fix not making sense to me. PCM samples can be negative, I think, but I believe that I had to change to using unsigned char explicitly.
Hope this helps,
Joe
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