This is more spec-compliant because it does not rely
on dead-code elimination by the compiler. Especially
MSVC has problems with this, as can be seen in
https://ffmpeg.org/pipermail/ffmpeg-devel/2022-May/296373.html
or
https://ffmpeg.org/pipermail/ffmpeg-devel/2022-May/297022.html
This commit does not eliminate every instance where we rely
on dead code elimination: It only tackles branching to
the initialization of arch-specific dsp code, not e.g. all
uses of CONFIG_ and HAVE_ checks. But maybe it is already
enough to compile FFmpeg with MSVC with whole-programm-optimizations
enabled (if one does not disable too many components).
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
This is as far as 22.2 follows the same channel order as
WaveFormatExtensible's channel mask (and the AV_CH_* defines).
After LFE2 the side channels would follow, but that offset of
one stops us from utilizing them without further tweaks.
This change was verified by using swresample to downmix to 5.1,
and then feeding that to WASAPI.
Only this sub-set of channels actually follows the bit mask order
in the official 22.2 channel mapping. Additionally, the 5.1 channels
are there for backwards compatibility with the previous system.
This enables the utilization of 22.2 content until a proper down/up
matrix is added into swresample.
These bits are utilized by channel layouts such as 22.2. If those
are dropped, the returned channel layout is no longer a match
against the AV_CH_LAYOUT define when returned from this function.
Rematrixing supports up to 64 channels. However, there is only a limited number of channel layouts defined. Since the in/out channel count is currently obtained from the channel layout, for undefined layouts (e.g. for 9, 10, 11 channels etc.) the rematrixing fails.
This patch changes rematrix init methods to use in (used) and out channel count directly instead of computing it from channel layout.
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
Prefer direct in/out channel count values over channel layout, when
available. Fixes a pan filter bug (ticket #6790).
Signed-off-by: Tobias Rapp <t.rapp@noa-archive.com>
This fixes the sum of the integer coefficients ending up summing to a value
larger than the value representing unity.
This issue occurs with qN0.dts when converting to stereo
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
This avoids several issue like calculating sum/maxcoef
incorrectly due to adding up matrix entries that will
be overwritten, as well as out-of-range writes to
s->matrix if the maximum allowed number of channels is used.
Signed-off-by: Reimar Döffinger <Reimar.Doeffinger@gmx.de>
We only actually need to use a tiny part of it.
Unfortunately we seem to have no real test coverage on
the code, so this is a bit risky.
Signed-off-by: Reimar Döffinger <Reimar.Doeffinger@gmx.de>
Fixes Ticket2859
Note, testcases related to the downmix channels are welcome.
(id like to make sure this is working correctly now, as obviously it didnt
work before ...)
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
Andreas Rheinhardt
James Almer
Jan Ekström
Marcin Gorzel
Tobias Rapp
Carl Eugen Hoyos
Diego Biurrun
Carl Eugen Hoyos
Vodyannikov Aleksandr
Michael Niedermayer
wm4
Michael Niedermayer
Reimar Döffinger
Nicolas George
Clément Bœsch
Paul B Mahol
Stefano Sabatini