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carlemac2009
Beginner
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Use of G.726 Codec for G.726 Annex A

Hi All,

I'm attempting to use the G.726 Codec in a context where it needs to produce the Annex A output. I understand only slightly the distinction between theNON Annex A and Annex A format - it has something to do with linear coding where the only the 14 most significant bits are used in Annex A.

Could someone please advise on the best use of the G.726 codec for this purpose? I don't see any command-line options to pass the codec which wouldsignal that I need G.726 Annex A output.

TIA,

Carl E. McMillin
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Vyacheslav_Baranniko
New Contributor II
67 Views

Quoting - carlemac2009
Hi All,

I'm attempting to use the G.726 Codec in a context where it needs to produce the Annex A output. I understand only slightly the distinction between theNON Annex A and Annex A format - it has something to do with linear coding where the only the 14 most significant bits are used in Annex A.

Could someone please advise on the best use of the G.726 codec for this purpose? I don't see any command-line options to pass the codec which wouldsignal that I need G.726 Annex A output.

TIA,

Carl E. McMillin

USC(see theIPP Samples/speech-codecs)among many others speech codecs supports alsoG726 w/withoutAnnex A. Please,takein account that USC G726 Encode functiondeamplifiesinputsignal at 12dB by shifting each 16bit sampletwo bits rightfeeding then into ippsEncode_G726_16s8u function.Thus, USC G726 Decode function restores only deamplified signal. You migth need to amplify it at 12 dB back to get decompressed copy of input signal.You might want touse IPP G726 functionality directly (G726functions group: ippsEncodeInit_G726_16s, ippsEncode_G726_16s8u, ippsDecodeInit_G726_16s, ippsDecode_G726_8u16s).
Vyacheslav
IPP, speech codecs
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