ref: 8faf57a9681a9e9d86e52bc472c1d9e2ee286ab0
dir: /src/dither.c/
/* Effect: dither/noise-shape Copyright (c) 2008 robs@users.sourceforge.net
*
* This library is free software; you can redistribute it and/or modify it
* under the terms of the GNU Lesser General Public License as published by
* the Free Software Foundation; either version 2.1 of the License, or (at
* your option) any later version.
*
* This library is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser
* General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with this library; if not, write to the Free Software Foundation,
* Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#ifdef NDEBUG /* Enable assert always. */
#undef NDEBUG /* Must undef above assert.h or other that might include it. */
#endif
#include "sox_i.h"
#include "getopt.h"
#include <assert.h>
#define PREC effp->out_signal.precision
#define RAND_CONST 140359821
static int32_t rand_ = ~RAND_CONST;
#define RAND_ (rand_ = rand_ * RAND_CONST + 1)
typedef enum {Pdf_rectangular, Pdf_triangular, Pdf_gaussian} pdf_type_t;
static lsx_enum_item const pdf_types[] = {
LSX_ENUM_ITEM(Pdf_,rectangular)
LSX_ENUM_ITEM(Pdf_,triangular)
LSX_ENUM_ITEM(Pdf_,gaussian)
{0, 0}};
typedef enum {
Shape_none, Shape_lipshitz, Shape_f_weighted, Shape_modified_e_weighted,
Shape_improved_e_weighted, Shape_gesemann, Shape_shibata, Shape_low_shibata, Shape_high_shibata
} filter_name_t;
static lsx_enum_item const filter_names[] = {
LSX_ENUM_ITEM(Shape_,none)
LSX_ENUM_ITEM(Shape_,lipshitz)
{"f-weighted", Shape_f_weighted},
{"modified-e-weighted", Shape_modified_e_weighted},
{"improved-e-weighted", Shape_improved_e_weighted},
LSX_ENUM_ITEM(Shape_,gesemann)
LSX_ENUM_ITEM(Shape_,shibata)
{"low-shibata", Shape_low_shibata},
{"high-shibata", Shape_high_shibata},
{0, 0}};
typedef struct {
sox_rate_t rate;
enum {fir, iir} type ;
size_t len;
double const * coefs;
filter_name_t name;
} filter_t;
static double const lip44[] = {2.033, -2.165, 1.959, -1.590, .6149};
static double const fwe44[] = {2.412, -3.370, 3.937, -4.174, 3.353, -2.205, 1.281, -.569, .0847};
static double const mew44[] = {1.662, -1.263, .4827, -.2913, .1268, -.1124, .03252, -.01265, -.03524};
static double const iew44[] = {2.847, -4.685, 6.214, -7.184, 6.639, -5.032, 3.263, -1.632, .4191};
static double const ges44[] = {2.2061, -.4706, -.2534, -.6214, 1.0587, .0676, -.6054, -.2738};
static double const ges48[] = {2.2374, -.7339, -.1251, -.6033, .903, .0116, -.5853, -.2571};
static double const shi48[] = {
2.8720729351043701172, -5.0413231849670410156, 6.2442994117736816406, -5.8483986854553222656,
3.7067542076110839844, -1.0495119094848632812, -1.1830236911773681641, 2.1126792430877685547,
-1.9094531536102294922, 0.99913084506988525391, -0.17090806365013122559, -0.32615602016448974609,
0.39127644896507263184, -0.26876461505889892578, 0.097676105797290802002,-0.023473845794796943665,
}; /* 48k, N=16, amp=18 */
static double const shi44[] = {
2.6773197650909423828, -4.8308925628662109375, 6.570110321044921875, -7.4572014808654785156,
6.7263274192810058594, -4.8481650352478027344, 2.0412089824676513672, 0.7006359100341796875,
-2.9537565708160400391, 4.0800385475158691406, -4.1845216751098632812, 3.3311812877655029297,
-2.1179926395416259766, 0.879302978515625, -0.031759146600961685181,-0.42382788658142089844,
0.47882103919982910156, -0.35490813851356506348, 0.17496839165687561035, -0.060908168554306030273,
}; /* 44.1k, N=20, amp=27 */
static double const shi38[] = {
1.6335992813110351562, -2.2615492343902587891, 2.4077029228210449219, -2.6341717243194580078,
2.1440362930297851562, -1.8153258562088012695, 1.0816224813461303711, -0.70302653312683105469,
0.15991993248462677002, 0.041549518704414367676,-0.29416576027870178223, 0.2518316805362701416,
-0.27766478061676025391, 0.15785403549671173096, -0.10165894031524658203, 0.016833892092108726501,
}; /* 37.8k, N=16 */
static double const shi32[] = {
0.82901298999786376953, -0.98922657966613769531, 0.59825712442398071289, -1.0028809309005737305,
0.59938216209411621094, -0.79502451419830322266, 0.42723315954208374023, -0.54492527246475219727,
0.30792605876922607422, -0.36871799826622009277, 0.18792048096656799316, -0.2261127084493637085,
0.10573341697454452515, -0.11435490846633911133, 0.038800679147243499756,-0.040842197835445404053,
}; /* 32k, N=16 */
static double const shi22[] = {
0.065229974687099456787,-0.54981261491775512695, -0.40278548002243041992, -0.31783768534660339355,
-0.28201797604560852051, -0.16985194385051727295, -0.15433363616466522217, -0.12507140636444091797,
-0.08903945237398147583, -0.064410120248794555664,-0.047146003693342208862,-0.032805237919092178345,
-0.028495194390416145325,-0.011695005930960178375,-0.011831838637590408325,
}; /* 22.05k, N=15 */
static double const shl48[] = {
2.3925774097442626953, -3.4350297451019287109, 3.1853709220886230469, -1.8117271661758422852,
-0.20124770700931549072, 1.4759907722473144531, -1.7210904359817504883, 0.97746700048446655273,
-0.13790138065814971924, -0.38185903429985046387, 0.27421241998672485352, 0.066584214568138122559,
-0.35223302245140075684, 0.37672343850135803223, -0.23964276909828186035, 0.068674825131893157959,
}; /* 48k, N=16, amp=10 */
static double const shl44[] = {
2.0833916664123535156, -3.0418450832366943359, 3.2047898769378662109, -2.7571926116943359375,
1.4978630542755126953, -0.3427594602108001709, -0.71733748912811279297, 1.0737057924270629883,
-1.0225815773010253906, 0.56649994850158691406, -0.20968692004680633545, -0.065378531813621520996,
0.10322438180446624756, -0.067442022264003753662,-0.00495197344571352005,
}; /* 44.1k, N=15, amp=9 */
static double const shh44[] = {
3.0259189605712890625, -6.0268716812133789062, 9.195003509521484375, -11.824929237365722656,
12.767142295837402344, -11.917946815490722656, 9.1739168167114257812, -5.3712320327758789062,
1.1393624544143676758, 2.4484779834747314453, -4.9719839096069335938, 6.0392003059387207031,
-5.9359521865844726562, 4.903278350830078125, -3.5527443885803222656, 2.1909697055816650391,
-1.1672389507293701172, 0.4903914332389831543, -0.16519790887832641602, 0.023217858746647834778,
}; /* 44.1k, N=20 */
static const filter_t filters[] = {
{44100, fir, 5, lip44, Shape_lipshitz},
{46000, fir, 9, fwe44, Shape_f_weighted},
{46000, fir, 9, mew44, Shape_modified_e_weighted},
{46000, fir, 9, iew44, Shape_improved_e_weighted},
{48000, iir, 4, ges48, Shape_gesemann},
{44100, iir, 4, ges44, Shape_gesemann},
{48000, fir, 16, shi48, Shape_shibata},
{44100, fir, 20, shi44, Shape_shibata},
{37800, fir, 16, shi38, Shape_shibata},
{32000, fir, 16, shi32, Shape_shibata},
{22050, fir, 15, shi22, Shape_shibata},
{48000, fir, 16, shl48, Shape_low_shibata},
{44100, fir, 15, shl44, Shape_low_shibata},
{44100, fir, 20, shh44, Shape_high_shibata},
{ 0, fir, 0, NULL, Shape_none},
};
#define MAX_N 30
typedef struct {
pdf_type_t pdf;
filter_name_t filter_name;
double am0, am1, depth;
double previous_errors[MAX_N * 2];
double previous_outputs[MAX_N * 2];
size_t pos;
double const * coefs;
int (*flow)(sox_effect_t *, const sox_sample_t *, sox_sample_t *, size_t *, size_t *);
} priv_t;
#define CONVOLVE _ _ _ _
#define NAME flow_iir_4
#define N 4
#include "dither_iir.h"
#define CONVOLVE _ _ _ _ _
#define NAME flow_fir_5
#define N 5
#include "dither_fir.h"
#define CONVOLVE _ _ _ _ _ _ _ _ _
#define NAME flow_fir_9
#define N 9
#include "dither_fir.h"
#define CONVOLVE _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
#define NAME flow_fir_15
#define N 15
#include "dither_fir.h"
#define CONVOLVE _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
#define NAME flow_fir_16
#define N 16
#include "dither_fir.h"
#define CONVOLVE _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
#define NAME flow_fir_20
#define N 20
#include "dither_fir.h"
static int flow_no_shape(sox_effect_t * effp, const sox_sample_t * ibuf,
sox_sample_t * obuf, size_t * isamp, size_t * osamp)
{
priv_t * p = (priv_t *)effp->priv;
size_t len = *isamp = *osamp = min(*isamp, *osamp);
int dummy = 0;
while (len--) {
double d = *ibuf++ + p->am0 * RAND_ + p->am1 * RAND_;
*obuf++ = SOX_ROUND_CLIP_COUNT(d, dummy);
}
return SOX_SUCCESS;
}
static int getopts(sox_effect_t * effp, int argc, char * * argv)
{
priv_t * p = (priv_t *)effp->priv;
int c;
p->pdf = Pdf_triangular;
while ((c = getopt(argc, argv, "+rtsf:")) != -1) switch (c) {
case 'r': p->pdf = Pdf_rectangular; break;
case 't': p->pdf = Pdf_triangular ; break;
case 's': p->filter_name = Shape_shibata; break;
case 'f':
p->filter_name = lsx_enum_option(c, filter_names);
if (p->filter_name == INT_MAX)
return SOX_EOF;
break;
default: lsx_fail("invalid option `-%c'", optopt); return lsx_usage(effp);
}
argc -= optind, argv += optind;
p->depth = 1;
do {NUMERIC_PARAMETER(depth, .5, 1)} while (0);
return argc? lsx_usage(effp) : SOX_SUCCESS;
}
static int start(sox_effect_t * effp)
{
priv_t * p = (priv_t *)effp->priv;
if (PREC >= 24)
return SOX_EFF_NULL; /* Dithering not needed at this resolution */
if (!p->filter_name)
p->flow = flow_no_shape;
else {
filter_t const * f;
for (f = filters; f->len && (f->name != p->filter_name || fabs(effp->in_signal.rate - f->rate) / f->rate > .05); ++f);
if (!f->len) {
lsx_fail("no `%s' filter is available for rate %g", lsx_find_enum_value(p->filter_name, filter_names)->text, effp->in_signal.rate);
return SOX_EOF;
}
assert(f->len <= MAX_N);
if (f->type == fir) switch(f->len) {
case 5: p->flow = flow_fir_5 ; break;
case 9: p->flow = flow_fir_9 ; break;
case 15: p->flow = flow_fir_15; break;
case 16: p->flow = flow_fir_16; break;
case 20: p->flow = flow_fir_20; break;
default: assert(sox_false);
} else switch(f->len) {
case 4: p->flow = flow_iir_4 ; break;
default: assert(sox_false);
}
p->coefs = f->coefs;
}
p->am1 = p->depth / (1 << PREC);
p->am0 = (p->pdf == Pdf_triangular) * p->am1;
lsx_debug("pdf=%s filter=%s depth=%g", lsx_find_enum_value(p->pdf, pdf_types)->text, lsx_find_enum_value(p->filter_name, filter_names)->text, p->depth);
return SOX_SUCCESS;
}
static int flow(sox_effect_t * effp, const sox_sample_t * ibuf,
sox_sample_t * obuf, size_t * isamp, size_t * osamp)
{
priv_t * p = (priv_t *)effp->priv;
return p->flow(effp, ibuf, obuf, isamp, osamp);
}
sox_effect_handler_t const * sox_dither_effect_fn(void)
{
static sox_effect_handler_t handler = {
"dither", "[-r|-t] [-s|-f filter] [depth]"
"\n -r Rectangular PDF"
"\n -t Triangular PDF (default)"
"\n -s Shape noise (with shibata filter)"
"\n -f name Set shaping filter to one of: lipshitz, f-weighted,"
"\n modified-e-weighted, improved-e-weighted, gesemann,"
"\n shibata, low-shibata, high-shibata."
"\n depth Noise depth; 0.5 to 1; default 1",
SOX_EFF_GETOPT | SOX_EFF_PREC, getopts, start, flow, 0, 0, 0, sizeof(priv_t)
};
return &handler;
}