Re: AudioFile doesn't Honor AIFF block-align offset
Re: AudioFile doesn't Honor AIFF block-align offset
- Subject: Re: AudioFile doesn't Honor AIFF block-align offset
- From: William Stewart <email@hidden>
- Date: Fri, 1 Jul 2005 18:16:51 -0700
That's not entirely unexpected behaviour - I'm presuming that you mean:
AudioFileReadBytes ( AudioFileID inAudioFile,
Boolean inUseCache,
SInt64 inStartingByte,
UInt32 *ioNumBytes,
void *outBuffer)
This is a basic routine where the purpose is to read raw bytes from
the data chunk of an audio file.
AudioFileReadPackets however should definitely only give you back
Audio Data, so we should check that call with the example files
you've posted
Thanks
Bill
On 01/07/2005, at 5:44 PM, Art Gillespie wrote:
Given an AIFF with the SSND chunk's offset field set to something
other than 0, AudioFileGetBytes returns the entire WaveFormData
field with all of the initial pad bytes. Depending on the offset,
the effects when played back run from undetectable to monitor-
destroying.
I've worked around this by reading in the offset myself and passing
it to AudioFileGetBytes' inStartingByte parameter (and subtracting
the offset from the value returned by
kAudioFilePropertyAudioDataByteCount).
I've posted two real-world files which demonstrate this (i.e., both
have SSND.offset > 0):
http://art.bitshiftaudio.com/download/34snare1.aif
http://art.bitshiftaudio.com/download/34snare2.aif
What I'm wondering if there's a property I should be using instead
to get the proper offset to pass to AudioFileGetBytes or if this is
an oversight in the AudioFile implementation.
Best,
Art
Glaresoft, Inc.
520.245.7839
_______________________________________________
Do not post admin requests to the list. They will be ignored.
Coreaudio-api mailing list (email@hidden)
Help/Unsubscribe/Update your Subscription:
This email sent to email@hidden
--
mailto:email@hidden
tel: +1 408 974 4056
________________________________________________________________________
__
"Much human ingenuity has gone into finding the ultimate Before.
The current state of knowledge can be summarized thus:
In the beginning, there was nothing, which exploded" - Terry Pratchett
________________________________________________________________________
__
_______________________________________________
Do not post admin requests to the list. They will be ignored.
Coreaudio-api mailing list (email@hidden)
Help/Unsubscribe/Update your Subscription:
This email sent to email@hidden