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Enable setting of global output samplerate on certain targets.

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Replaces the NATIVE_FREQUENCY constant with a configurable frequency.

The user may select 48000Hz if the hardware supports it. The default is
still 44100Hz and the minimum is 44100Hz. The setting is located in the
playback settings, under "Frequency".

"Frequency" was duplicated in english.lang for now to avoid having to
fix every .lang file for the moment and throwing everything out of sync
because of the new play_frequency feature in features.txt. The next
cleanup should combine it with the one included for recording and
generalize the ID label.

If the hardware doesn't support 48000Hz, no setting will be available.

On particular hardware where very high rates are practical and desireable,
the upper bound can be extended by patching.

The PCM mixer can be configured to play at the full hardware frequency
range. The DSP core can configure to the hardware minimum up to the
maximum playback setting (some buffers must be reserved according to
the maximum rate).

If only 44100Hz is supported or possible on a given target for playback,
using the DSP and mixer at other samperates is possible if the hardware
offers them.

Change-Id: I6023cf0c0baa8bc6292b6919b4dd3618a6a25622
Reviewed-on: http://gerrit.rockbox.org/479
Reviewed-by: Michael Sevakis <jethead71@rockbox.org>
Tested-by: Michael Sevakis <jethead71@rockbox.org>
This commit is contained in:
Michael Sevakis 2013-05-23 13:58:51 -04:00
parent 00faabef5e
commit d37bf24d90
44 changed files with 677 additions and 230 deletions
Download patch file Download diff file Expand all files Collapse all files

117
lib/rbcodec/dsp/crossfeed.c
View file

@ -24,6 +24,7 @@
#include "fixedpoint.h"
#include "fracmul.h"
#include "replaygain.h"
#include "dsp_misc.h"
#include "dsp_proc_entry.h"
#include "dsp_filter.h"
#include "crossfeed.h"
@ -44,32 +45,40 @@ void crossfeed_meier_process(struct dsp_proc_entry *this,
* to listen to on headphones with no crossfeed.
*/
#define DELAY_LEN(fs) ((300*(fs) / 1000000)*2) /* ~300 uS */
/* Crossfeed */
static struct crossfeed_state
{
int32_t gain; /* 00h: Direct path gain */
int32_t coefs[3]; /* 04h: Coefficients for the shelving filter */
union
{
struct /* 10h: Data for meier crossfeed */
struct /* Data for meier crossfeed */
{
int32_t vcl;
int32_t vcr;
int32_t vdiff;
int32_t coef1;
int32_t coef2;
int32_t reserved; /* 00h: Reserved: overlaps gain */
int32_t vcl; /* 04h: Left filter output */
int32_t vcr; /* 08h: Right filter output */
int32_t vdiff; /* 0ch: L-R difference signal */
int32_t coef1; /* 10h: Left/right filter coef */
int32_t coef2; /* 14h: Crossfeed filter coef */
};
struct /* 10h: Data for custom crossfeed */
struct /* Data for custom crossfeed */
{
int32_t gain; /* 00h: Direct path gain */
int32_t coefs[3]; /* 04h: Filter coefficients: b0, b1, a1 */
int32_t history[4]; /* 10h: Format is x[n - 1], y[n - 1] (L + R) */
int32_t delay[13*2];/* 20h: Delay line buffer (L + R interleaved) */
int32_t *index; /* 20h: Current pointer into the delay line */
int32_t *index_max; /* 24h: Current max pointer of delay line */
/* 28h: Delay line buffer (L + R interleaved) */
int32_t delay[DELAY_LEN(DSP_OUT_MAX_HZ)]; /* Target-dependent size */
};
};
int32_t *index; /* 88h: Current pointer into the delay line */
/* 8ch */
} crossfeed_state IBSS_ATTR;
static int crossfeed_type = CROSSFEED_TYPE_NONE;
/* Cached custom settings */
static long crossfeed_lf_gain;
static long crossfeed_hf_gain;
static long crossfeed_cutoff;
/* Discard the sample histories */
static void crossfeed_flush(struct dsp_proc_entry *this)
@ -82,12 +91,49 @@ static void crossfeed_flush(struct dsp_proc_entry *this)
}
else
{
memset(state->history, 0,
sizeof (state->history) + sizeof (state->delay));
memset(state->history, 0, sizeof (state->history));
memset(state->delay, 0, sizeof (state->delay));
state->index = state->delay;
}
}
static void crossfeed_meier_update_filter(struct crossfeed_state *state,
unsigned int fout)
{
/* 1 / (F.Rforward.C) */
state->coef1 = fp_div(2128, fout, 31);
/* 1 / (F.Rcross.C) */
state->coef2 = fp_div(1000, fout, 31);
}
static void crossfeed_custom_update_filter(struct crossfeed_state *state,
unsigned int fout)
{
long lf_gain = crossfeed_lf_gain;
long hf_gain = crossfeed_hf_gain;
long cutoff = crossfeed_cutoff;
int32_t *c = state->coefs;
long scaler = get_replaygain_int(lf_gain * 10) << 7;
cutoff = fp_div(cutoff, fout, 32);
hf_gain -= lf_gain;
/* Divide cutoff by sqrt(10^(hf_gain/20)) to place cutoff at the -3 dB
* point instead of shelf midpoint. This is for compatibility with the old
* crossfeed shelf filter and should be removed if crossfeed settings are
* ever made incompatible for any other good reason.
*/
cutoff = fp_div(cutoff, get_replaygain_int(hf_gain*5), 24);
filter_shelf_coefs(cutoff, hf_gain, false, c);
/* Scale coefs by LF gain and shift them to s0.31 format. We have no gains
* over 1 and can do this safely
*/
c[0] = FRACMUL_SHL(c[0], scaler, 4);
c[1] = FRACMUL_SHL(c[1], scaler, 4);
c[2] <<= 4;
}
/** DSP interface **/
@ -114,24 +160,13 @@ void dsp_set_crossfeed_direct_gain(int gain)
/* Both gains should be below 0 dB */
void dsp_set_crossfeed_cross_params(long lf_gain, long hf_gain, long cutoff)
{
int32_t *c = crossfeed_state.coefs;
long scaler = get_replaygain_int(lf_gain * 10) << 7;
crossfeed_lf_gain = lf_gain;
crossfeed_hf_gain = hf_gain;
crossfeed_cutoff = cutoff;
cutoff = 0xffffffff / NATIVE_FREQUENCY * cutoff;
hf_gain -= lf_gain;
/* Divide cutoff by sqrt(10^(hf_gain/20)) to place cutoff at the -3 dB
* point instead of shelf midpoint. This is for compatibility with the old
* crossfeed shelf filter and should be removed if crossfeed settings are
* ever made incompatible for any other good reason.
*/
cutoff = fp_div(cutoff, get_replaygain_int(hf_gain*5), 24);
filter_shelf_coefs(cutoff, hf_gain, false, c);
/* Scale coefs by LF gain and shift them to s0.31 format. We have no gains
* over 1 and can do this safely
*/
c[0] = FRACMUL_SHL(c[0], scaler, 4);
c[1] = FRACMUL_SHL(c[1], scaler, 4);
c[2] <<= 4;
struct dsp_config *dsp = dsp_get_config(CODEC_IDX_AUDIO);
crossfeed_custom_update_filter(&crossfeed_state,
dsp_get_output_frequency(dsp));
}
#if !defined(CPU_COLDFIRE) && !defined(CPU_ARM)
@ -147,6 +182,7 @@ void crossfeed_process(struct dsp_proc_entry *this, struct dsp_buffer **buf_p)
int32_t *coefs = &state->coefs[0];
int32_t gain = state->gain;
int32_t *di = state->index;
int32_t *di_max = state->index_max;
int count = buf->remcount;
@ -176,7 +212,7 @@ void crossfeed_process(struct dsp_proc_entry *this, struct dsp_buffer **buf_p)
buf->p32[1][i] = FRACMUL(right, gain) + hist_l[1];
/* Wrap delay line index if bigger than delay line size */
if (di >= delay + 13*2)
if (di >= di_max)
di = delay;
}
@ -234,17 +270,21 @@ static void update_process_fn(struct dsp_proc_entry *this,
struct dsp_config *dsp)
{
struct crossfeed_state *state = (struct crossfeed_state *)this->data;
dsp_proc_fn_type fn = crossfeed_process;
dsp_proc_fn_type fn;
unsigned int fout = dsp_get_output_frequency(dsp);
if (crossfeed_type != CROSSFEED_TYPE_CUSTOM)
{
/* Set up for Meier */
/* 1 / (F.Rforward.C) */
state->coef1 = (0x7fffffff / NATIVE_FREQUENCY) * 2128;
/* 1 / (F.Rcross.C) */
state->coef2 = (0x7fffffff / NATIVE_FREQUENCY) * 1000;
crossfeed_meier_update_filter(state, fout);
fn = crossfeed_meier_process;
}
else
{
state->index_max = state->delay + DELAY_LEN(fout);
crossfeed_custom_update_filter(state, fout);
fn = crossfeed_process;
}
if (this->process != fn)
{
@ -292,6 +332,7 @@ static intptr_t crossfeed_configure(struct dsp_proc_entry *this,
if (value == 0)
this->data = (intptr_t)&crossfeed_state;
case DSP_SET_OUT_FREQUENCY:
update_process_fn(this, dsp);
break;