[email protected] (Niels Möller) writes:

> E.g., it's likely that I get the channel order wrong when adding the
> residuals.

Speaking of channel order... The channel set subheader contains a field

  nChMask (Channel Mask for Set)

  This is present only if bOne2OneMapChannels2Speakers is true. When
  bChMaskEnabled is set, this field indicates which pre-defined channel
  positions apply. (See clause C.7 for details).

As far as I understand, this specifies which channels are in the channel
set, where I guess that the location of the least significant 1 bit
gives the type of the first channel, etc. In the test stream, the valus
is 0x1f. However, C.7 is the section on entropy coding which says
nothing about channel orders, so that reference is not helpful.

There is a table 7-10 (page 101) which could be related, but I don't
quite understand it. E.g., in that table, bit 1 (0x0002) represents the
*two* channels "Left/Right in front", and 0x1f would mean front center,
front left and right, rear left and right, lfe, and center rear, which
can't be right since that's exceeds the number of channels, which is 5.

So how should nChMask be interpreted?

Regards,
/Niels

-- 
Niels Möller. PGP-encrypted email is preferred. Keyid C0B98E26.
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