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wesk05 · (This post was last modified: 2017-01-12, 20:06 by wesk05.)

When I realize I have made a mistake, I do not hesitate to admit it. So, I admit that I was wrong when I said that AVRs decode Dolby Digital/DTS audio sent as linear PCM by accident. I had raised this question before, but never followed up on it: http://forum.kodi.tv/showthread.php?tid=...id=2149413

@Soli’s comment that it has worked on AVRs since the LaserDisc era made me look into the standards from that time. Indeed, the pre-1997 IEC958 standard have references about this. It has also been described in Annex B of A/52 (1995). Reference to this has since been removed from A/52. There is still a short reference to this in IEC-61937-1 under sec. 6.3.3 Burst spacing (which I seem to have overlooked although I have gone through the standards several times).

In short, this works by looking for Dolby Digital/DTS sync codes (Pa and Pb which are now part of the burst-preamble of IEC 61937).
Dolby Digital sync code – 0xF872, 0x4E1F (32-bit)
DTS sync code – 0x7FFE8001 / 0x3F (32/38-bit)
You can reduce the false detection rate by including the four “0” subframes in the burst-spacing along with Pa and Pb to form an extended 96-bit sync code.

(2017-01-03, 00:56)Soli Wrote: It's not an accident AVRs decode bitstream content even though they stream is flagged as linear pcm.