rockbox/lib/rbcodec
Michael Sevakis f5a5b94686 Implement universal in-PCM-driver software volume control.
Implements double-buffered volume, balance and prescaling control in
the main PCM driver when HAVE_SW_VOLUME_CONTROL is defined ensuring
that all PCM is volume controlled and level changes are low in latency.

Supports -73 to +6 dB using a 15-bit factor so that no large-integer
math is needed.

Low-level hardware drivers do not have to implement it themselves but
parameters can be changed (currently defined in pcm-internal.h) to work
best with a particular SoC or to provide different volume ranges.

Volume and prescale calls should be made in the codec driver. It should
appear as a normal hardware interface. PCM volume calls expect .1 dB
units.

Change-Id: Idf6316a64ef4fb8abcede10707e1e6c6d01d57db
Reviewed-on: http://gerrit.rockbox.org/423
Reviewed-by: Michael Sevakis <jethead71@rockbox.org>
Tested-by: Michael Sevakis <jethead71@rockbox.org>
2013-04-11 22:55:16 +02:00
..
codecs Move fixedpoint.h to be accessible in /firmware. 2013-04-10 13:28:35 -04:00
dsp Implement universal in-PCM-driver software volume control. 2013-04-11 22:55:16 +02:00
metadata VGM Codec: Improve time and fade behavior. Tweak minor misc. 2013-03-06 19:47:05 -05:00
test rbcodec: abstract tdspeed buffer allocation 2012-05-07 10:29:07 +02:00
platform.h Remove STATICIRAM hack 2012-05-08 22:46:12 +02:00
rbcodec.make Add rbcodecplatform.h and rbcodecconfig.h. 2012-05-03 14:49:35 +02:00
rbcodecconfig-example.h Rename HAVE_PITCHSCREEN to HAVE_PITCHCONTROL 2012-05-09 14:32:38 +02:00
rbcodecplatform-unix.h rbcodec: abstract tdspeed buffer allocation 2012-05-07 10:29:07 +02:00
SOURCES Rename HAVE_PITCHSCREEN to HAVE_PITCHCONTROL 2012-05-09 14:32:38 +02:00