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View Full Version : a problem about PCM sampling rate in spec 1.0.1



yxyybbs
08-21-2011, 08:18 PM
In Page 489 of spec 1.0.1,
I noticed that "pcm.samplesPerSec = SL_SAMPLINGRATE_44_1" and pcm.samplesPerSec was defined samples per second.
however, in Page 466, the spec said "These macros specify the commonly used sampling rates (in milliHertz) supported by most audio I/O devices."
:roll:

Erik
08-27-2011, 02:23 AM
This is one of those embarrassing things that happen even though you’ve spent hundreds of hours reading through the spec over and over looking for errors. :oops:

samplesPerSec should have been named samplesPerMilliSec. If you look at the definition of SLDataFormat_PCM in the OpenSL ES 1.1 specification, we made a clarification as to this error. Additionally we also deprecated the struct in favor of one that has the member correctly named.

In the meanwhile, I am working with the working group members to ensure that I give you a technically correct answer for proper usage in 1.0.1 according to the conformance tests and existing implementations.

Best,

Erik

Erik
09-07-2011, 01:51 PM
To further clarify this issue, I checked the conformance tests for 1.0.1 and talked to the implementers of the publicly available implementations. In all cases, the correct usage is to pass the value in milliHertz.

Best,

Erik

yxyybbs
09-08-2011, 07:38 AM
Thanks!

First time to ask a question here, and your reply is very helpful,

best wishes!