Lines Matching +full:pcm +full:- +full:interface +full:- +full:rate
2 .\" Copyright (c) 2009-2011 Joel Dahl <joel@FreeBSD.org>
31 .Nm pcm ,
35 PCM audio device infrastructure
39 .Bd -ragged -offset indent
49 and provides PCM audio record and playback once it attaches.
60 driver are: multichannel audio, per-application
62 duplex operation, bit perfect audio, rate conversion and low latency
74 .Bl -bullet -compact
118 .Xr snd_uaudio 4 (auto-loaded on device plug)
145 .Bl -tag -width ".Va snd_driver_load" -offset indent
166 .Va hint.pcm.0.line Ns = Ns Qq Li 0 .
177 re-routing of channels.
178 This provides a base interface for related multichannel
186 .Va dev.pcm.%d.[play|rec].vchanformat
198 Commonly used for ear-candy or frequency compensation due to the vast
201 .Va hint.pcm.%d.eq
210 interface but can only be manipulated while the device is inactive.
232 .Bl -tag -width indent
233 .It Va hint.pcm.%d.eq
239 .It Va hint.pcm.%d.vpc
253 .Va dev.pcm.*
255 .Bl -tag -width indent
261 .Bl -tag -width 2n
262 .It -1
276 .Bl -tag -width 2n
302 Maximum allowable sample rate.
304 Minimum allowable sample rate.
314 Sample rate converter quality.
317 .Bl -tag -width 2n
324 Technically the quality is poor however, due to the lack of anti-aliasing
342 Sample rate rounding threshold, to avoid large prime division at the
361 rate, especially during high workload.
387 .Bl -tag -width 2n
412 when applications tries to re-open the same device.
424 .It Va dev.pcm.%d.bitperfect
427 matrixing, rate converting and equalizing.
431 If VCHANs are enabled, the bitperfect mode will use the VCHAN format/rate as
432 the definitive format/rate target.
436 .It Va dev.pcm.%d.[play|rec].vchans
442 .It Va dev.pcm.%d.[play|rec].vchanformat
448 .Bl -tag -width 2n
472 .It Va dev.pcm.%d.[play|rec].vchanmode
473 VCHAN format/rate selection.
475 .Bl -tag -width 2n
477 Channel mixing is done using fixed format/rate.
485 Channel mixing is done using fixed format/rate, but advanced operations such
499 channels with different format/rate.
501 be scanned, and the channel with the best format/rate (usually the
507 .It Va dev.pcm.%d.[play|rec].vchanrate
508 Sample rate speed for VCHAN mixing.
509 All playback paths will be converted to this sample rate before the mixing
511 .It Va dev.pcm.%d.polling
541 .Bl -tag -width ".Pa /dev/sndstat" -compact
590 .Dl mixer -d pcm1
592 .Bl -diag
593 .It pcm%d:play:%d:dsp%d.p%d: play interrupt timeout, channel dead
634 .%T "Cookbook formulae for audio EQ biquad filter coefficients (Audio-EQ-Cookbook.txt), by Robert Bristow-Johnson"
635 .%U "https://www.musicdsp.org/en/latest/Filters/197-rbj-audio-eq-cookbook.html"
642 .%T "Polynomial Interpolators for High-Quality Resampling of Oversampled Audio, by Olli Niemitalo"
643 .%U "http://yehar.com/blog/wp-content/uploads/2009/08/deip.pdf"
655 .Nm pcm ,
666 .An -nosplit
669 .Nm pcm
674 .An Seigo Tanimura Aq Mt tanimura@r.dl.itc.u-tokyo.ac.jp