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sandeephrnayak
05-23-2007, 04:45 AM
According to spec doc "omx_dl_v1_0_1.pdf" there are 3 API's
OMXResult omxACMP3_HuffmanDecode_S32()
OMXResult omxACMP3_HuffmanDecodeSfb_S32()
OMXResult omxACMP3_HuffmanDecodeSfbMbp_S32()

But there is no detailed description about these API's, I mean how these API's are different from each other as far as their body's concerned. Any pointer on this is appreciated.

Regards,
Sandeep H.R

hfrancis
01-15-2008, 10:32 AM
Hi Sandeep,

I'm not an audio expert, so looking at the specification it appears the second and third of these functions have "Sfb" in the name which indicates that they use scale factor bands (so it probably scales the results somehow).

And these two "Sfb" functions have an extra parameter "pSfbTableLong" which describes the scale factor bands (see the description of this parameter).

The third function is called "SfbMbp" which appears to have a mixture of Long and Short blocks, and has two extra parameters ("pSfbTableShort", and "pMbpTable"). See the parameters' descriptions on how these work.

The Long and Short block scalefactor band tables are described in sections 3.1.2.3 and 3.1.2.4 of the latest specification (v1.0.2 due to be published on the Khronos website in the next week or two).

Regards, Hedley