/* GStreamer
* Copyright (C) 2007 Sebastian Dröge <slomo@circular-chaos.org>
*
* gstaudioquantize.c: quantizes audio to the target format and optionally
* applies dithering and noise shaping.
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Library General Public
* License as published by the Free Software Foundation; either
* version 2 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
* Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public
* License along with this library; if not, write to the
* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
* Boston, MA 02111-1307, USA.
*/
/*
* FIXME: When doing dithering with int as intermediate format
* one gets audible harmonics while the noise floor is
* constant for double as intermediate format!
*/
/* TODO: - Maybe drop 5-pole noise shaping and use coefficients
* generated by dmaker
* http://shibatch.sf.net
*/
#include <gst/gst.h>
#include <string.h>
#include <math.h>
#include "audioconvert.h"
#include "gstaudioquantize.h"
#define MAKE_QUANTIZE_FUNC_NAME(name) \
gst_audio_quantize_quantize_##name
/* Quantize functions for gint32 as intermediate format */
#define MAKE_QUANTIZE_FUNC_I(name, DITHER_INIT_FUNC, ADD_DITHER_FUNC, \
ROUND_FUNC) \
static void \
MAKE_QUANTIZE_FUNC_NAME (name) (AudioConvertCtx *ctx, gint32 *src, \
gint32 *dst, gint count) \
{ \
gint scale = ctx->out_scale; \
gint channels = ctx->out.channels; \
gint chan_pos; \
\
if (scale > 0) { \
gint32 tmp; \
guint32 mask = 0xffffffff & (0xffffffff << scale); \
guint32 bias = 1U << (scale - 1); \
DITHER_INIT_FUNC() \
\
for (;count;count--) { \
for (chan_pos = 0; chan_pos < channels; chan_pos++) { \
tmp = *src++; \
ADD_DITHER_FUNC() \
ROUND_FUNC() \
*dst = tmp & mask; \
dst++; \
} \
} \
} else { \
for (;count;count--) { \
for (chan_pos = 0; chan_pos < channels; chan_pos++) { \
*dst = *src++; \
dst++; \
} \
} \
} \
}
/* Quantize functions for gdouble as intermediate format with
* int as target */
#define MAKE_QUANTIZE_FUNC_F(name, DITHER_INIT_FUNC, NS_INIT_FUNC, \
ADD_NS_FUNC, ADD_DITHER_FUNC, \
UPDATE_ERROR_FUNC) \
static void \
MAKE_QUANTIZE_FUNC_NAME (name) (AudioConvertCtx *ctx, gdouble *src, \
gdouble *dst, gint count) \
{ \
gint scale = ctx->out_scale; \
gint channels = ctx->out.channels; \
gint chan_pos; \
gdouble factor = (1U<<(32-scale-1)) - 1; \
\
if (scale > 0) { \
gdouble tmp; \
DITHER_INIT_FUNC() \
NS_INIT_FUNC() \
\
for (;count;count--) { \
for (chan_pos = 0; chan_pos < channels; chan_pos++) { \
tmp = *src++; \
ADD_NS_FUNC() \
ADD_DITHER_FUNC() \
tmp = floor(tmp * factor + 0.5); \
*dst = CLAMP (tmp, -factor - 1, factor); \
UPDATE_ERROR_FUNC() \
dst++; \
} \
} \
} else { \
for (;count;count--) { \
for (chan_pos = 0; chan_pos < channels; chan_pos++) { \
*dst = *src++ * 2147483647.0; \
dst++; \
} \
} \
} \
}
/* Rounding functions for int as intermediate format, only used when
* not using dithering. With dithering we include this offset in our
* dither noise instead. */
#define ROUND() \
if (tmp > 0 && G_MAXINT32 - tmp <= bias) \
tmp = G_MAXINT32; \
else \
tmp += bias;
#define NONE_FUNC()
/* Dithering definitions
* See http://en.wikipedia.org/wiki/Dithering or
* http://www.cadenzarecording.com/Dither.html for explainations.
*
* We already add the rounding offset to the dither noise here
* to have only one overflow check instead of two. */
#define INIT_DITHER_RPDF_I() \
gint32 rand; \
gint32 dither = (1<<(scale));
#define ADD_DITHER_RPDF_I() \
rand = g_rand_int_range (ctx->dither_random, bias - dither, \
bias + dither); \
if (rand > 0 && tmp > 0 && G_MAXINT32 - tmp <= rand) \
tmp = G_MAXINT32; \
else if (rand < 0 && tmp < 0 && G_MININT32 - tmp >= rand) \
tmp = G_MININT32; \
else \
tmp += rand;
#define INIT_DITHER_RPDF_F() \
gdouble dither = 1.0/(1U<<(32 - scale - 1));
#define ADD_DITHER_RPDF_F() \
tmp += g_rand_double_range (ctx->dither_random, - dither, \
dither);
#define INIT_DITHER_TPDF_I() \
gint32 rand; \
gint32 dither = (1<<(scale - 1)); \
bias = bias >> 1;
#define ADD_DITHER_TPDF_I() \
rand = g_rand_int_range (ctx->dither_random, bias - dither, \
bias + dither - 1) \
+ g_rand_int_range (ctx->dither_random, bias - dither, \
bias + dither - 1); \
if (rand > 0 && tmp > 0 && G_MAXINT32 - tmp <= rand) \
tmp = G_MAXINT32; \
else if (rand < 0 && tmp < 0 && G_MININT32 - tmp >= rand) \
tmp = G_MININT32; \
else \
tmp += rand;
#define INIT_DITHER_TPDF_F() \
gdouble dither = 1.0/(1U<<(32 - scale));
#define ADD_DITHER_TPDF_F() \
tmp += g_rand_double_range (ctx->dither_random, - dither, \
dither) \
+ g_rand_double_range (ctx->dither_random, - dither, \
dither);
#define INIT_DITHER_TPDF_HF_I() \
gint32 rand; \
gint32 dither = (1<<(scale-1)); \
gint32 *last_random = (gint32 *) ctx->last_random, tmp_rand; \
bias = bias >> 1;
#define ADD_DITHER_TPDF_HF_I() \
tmp_rand = g_rand_int_range (ctx->dither_random, bias - dither, \
bias + dither); \
rand = tmp_rand - last_random[chan_pos]; \
last_random[chan_pos] = tmp_rand; \
if (rand > 0 && tmp > 0 && G_MAXINT32 - tmp <= rand) \
tmp = G_MAXINT32; \
else if (rand < 0 && tmp < 0 && G_MININT32 - tmp >= rand) \
tmp = G_MININT32; \
else \
tmp += rand;
/* Like TPDF dither but the dither noise is oriented more to the
* higher frequencies */
#define INIT_DITHER_TPDF_HF_F() \
gdouble rand; \
gdouble dither = 1.0/(1U<<(32 - scale)); \
gdouble *last_random = (gdouble *) ctx->last_random, tmp_rand;
#define ADD_DITHER_TPDF_HF_F() \
tmp_rand = g_rand_double_range (ctx->dither_random, - dither, \
dither); \
rand = tmp_rand - last_random[chan_pos]; \
last_random[chan_pos] = tmp_rand; \
tmp += rand;
/* Noise shaping definitions.
* See http://en.wikipedia.org/wiki/Noise_shaping for explanations. */
/* Simple error feedback: Just accumulate the dithering and quantization
* error and remove it from each sample. */
#define INIT_NS_ERROR_FEEDBACK() \
gdouble orig; \
gdouble *errors = ctx->error_buf;
#define ADD_NS_ERROR_FEEDBACK() \
orig = tmp; \
tmp -= errors[chan_pos];
#define UPDATE_ERROR_ERROR_FEEDBACK() \
errors[chan_pos] += (*dst)/factor - orig;
/* Same as error feedback but also add 1/2 of the previous error value.
* This moves the noise a bit more into the higher frequencies. */
#define INIT_NS_SIMPLE() \
gdouble orig; \
gdouble *errors = ctx->error_buf, cur_error;
#define ADD_NS_SIMPLE() \
cur_error = errors[chan_pos*2] - 0.5 * errors[chan_pos*2 + 1]; \
tmp -= cur_error; \
orig = tmp;
#define UPDATE_ERROR_SIMPLE() \
errors[chan_pos*2 + 1] = errors[chan_pos*2]; \
errors[chan_pos*2] = (*dst)/factor - orig;
/* Noise shaping coefficients from[1], moves most power of the
* error noise into inaudible frequency ranges.
*
* [1]
* "Minimally Audible Noise Shaping", Stanley P. Lipshitz,
* John Vanderkooy, and Robert A. Wannamaker,
* J. Audio Eng. Soc., Vol. 39, No. 11, November 1991. */
static const gdouble ns_medium_coeffs[] = {
2.033, -2.165, 1.959, -1.590, 0.6149
};
#define INIT_NS_MEDIUM() \
gdouble orig; \
gdouble *errors = ctx->error_buf, cur_error; \
int j;
#define ADD_NS_MEDIUM() \
cur_error = 0.0; \
for (j = 0; j < 5; j++) \
cur_error += errors[chan_pos*5 + j] * ns_medium_coeffs[j]; \
tmp -= cur_error; \
orig = tmp;
#define UPDATE_ERROR_MEDIUM() \
for (j = 4; j > 0; j--) \
errors[chan_pos*5 + j] = errors[chan_pos*5 + j-1]; \
errors[chan_pos*5] = (*dst)/factor - orig;
/* Noise shaping coefficients by David Schleef, moves most power of the
* error noise into inaudible frequency ranges */
static const gdouble ns_high_coeffs[] = {
2.08484, -2.92975, 3.27918, -3.31399, 2.61339, -1.72008, 0.876066, -0.340122
};
#define INIT_NS_HIGH() \
gdouble orig; \
gdouble *errors = ctx->error_buf, cur_error; \
int j;
#define ADD_NS_HIGH() \
cur_error = 0.0; \
for (j = 0; j < 8; j++) \
cur_error += errors[chan_pos + j] * ns_high_coeffs[j]; \
tmp -= cur_error; \
orig = tmp;
#define UPDATE_ERROR_HIGH() \
for (j = 7; j > 0; j--) \
errors[chan_pos + j] = errors[chan_pos + j-1]; \
errors[chan_pos] = (*dst)/factor - orig;
MAKE_QUANTIZE_FUNC_I (signed_none_none, NONE_FUNC, NONE_FUNC, ROUND);
MAKE_QUANTIZE_FUNC_I (signed_rpdf_none, INIT_DITHER_RPDF_I, ADD_DITHER_RPDF_I,
NONE_FUNC);
MAKE_QUANTIZE_FUNC_I (signed_tpdf_none, INIT_DITHER_TPDF_I, ADD_DITHER_TPDF_I,
NONE_FUNC);
MAKE_QUANTIZE_FUNC_I (signed_tpdf_hf_none, INIT_DITHER_TPDF_HF_I,
ADD_DITHER_TPDF_HF_I, NONE_FUNC);
MAKE_QUANTIZE_FUNC_I (unsigned_none_none, NONE_FUNC, NONE_FUNC, ROUND);
MAKE_QUANTIZE_FUNC_I (unsigned_rpdf_none, INIT_DITHER_RPDF_I, ADD_DITHER_RPDF_I,
NONE_FUNC);
MAKE_QUANTIZE_FUNC_I (unsigned_tpdf_none, INIT_DITHER_TPDF_I, ADD_DITHER_TPDF_I,
NONE_FUNC);
MAKE_QUANTIZE_FUNC_I (unsigned_tpdf_hf_none, INIT_DITHER_TPDF_HF_I,
ADD_DITHER_TPDF_HF_I, NONE_FUNC);
MAKE_QUANTIZE_FUNC_F (float_none_error_feedback, NONE_FUNC,
INIT_NS_ERROR_FEEDBACK, ADD_NS_ERROR_FEEDBACK, NONE_FUNC,
UPDATE_ERROR_ERROR_FEEDBACK);
MAKE_QUANTIZE_FUNC_F (float_none_simple, NONE_FUNC, INIT_NS_SIMPLE,
ADD_NS_SIMPLE, NONE_FUNC, UPDATE_ERROR_SIMPLE);
MAKE_QUANTIZE_FUNC_F (float_none_medium, NONE_FUNC, INIT_NS_MEDIUM,
ADD_NS_MEDIUM, NONE_FUNC, UPDATE_ERROR_MEDIUM);
MAKE_QUANTIZE_FUNC_F (float_none_high, NONE_FUNC, INIT_NS_HIGH, ADD_NS_HIGH,
NONE_FUNC, UPDATE_ERROR_HIGH);
MAKE_QUANTIZE_FUNC_F (float_rpdf_error_feedback, INIT_DITHER_RPDF_F,
INIT_NS_ERROR_FEEDBACK, ADD_NS_ERROR_FEEDBACK, ADD_DITHER_RPDF_F,
UPDATE_ERROR_ERROR_FEEDBACK);
MAKE_QUANTIZE_FUNC_F (float_rpdf_simple, INIT_DITHER_RPDF_F, INIT_NS_SIMPLE,
ADD_NS_SIMPLE, ADD_DITHER_RPDF_F, UPDATE_ERROR_SIMPLE);
MAKE_QUANTIZE_FUNC_F (float_rpdf_medium, INIT_DITHER_RPDF_F, INIT_NS_MEDIUM,
ADD_NS_MEDIUM, ADD_DITHER_RPDF_F, UPDATE_ERROR_MEDIUM);
MAKE_QUANTIZE_FUNC_F (float_rpdf_high, INIT_DITHER_RPDF_F, INIT_NS_HIGH,
ADD_NS_HIGH, ADD_DITHER_RPDF_F, UPDATE_ERROR_HIGH);
MAKE_QUANTIZE_FUNC_F (float_tpdf_error_feedback, INIT_DITHER_TPDF_F,
INIT_NS_ERROR_FEEDBACK, ADD_NS_ERROR_FEEDBACK, ADD_DITHER_TPDF_F,
UPDATE_ERROR_ERROR_FEEDBACK);
MAKE_QUANTIZE_FUNC_F (float_tpdf_simple, INIT_DITHER_TPDF_F, INIT_NS_SIMPLE,
ADD_NS_SIMPLE, ADD_DITHER_TPDF_F, UPDATE_ERROR_SIMPLE);
MAKE_QUANTIZE_FUNC_F (float_tpdf_medium, INIT_DITHER_TPDF_F, INIT_NS_MEDIUM,
ADD_NS_MEDIUM, ADD_DITHER_TPDF_F, UPDATE_ERROR_MEDIUM);
MAKE_QUANTIZE_FUNC_F (float_tpdf_high, INIT_DITHER_TPDF_F, INIT_NS_HIGH,
ADD_NS_HIGH, ADD_DITHER_TPDF_F, UPDATE_ERROR_HIGH);
MAKE_QUANTIZE_FUNC_F (float_tpdf_hf_error_feedback, INIT_DITHER_TPDF_HF_F,
INIT_NS_ERROR_FEEDBACK, ADD_NS_ERROR_FEEDBACK, ADD_DITHER_TPDF_HF_F,
UPDATE_ERROR_ERROR_FEEDBACK);
MAKE_QUANTIZE_FUNC_F (float_tpdf_hf_simple, INIT_DITHER_TPDF_HF_F,
INIT_NS_SIMPLE, ADD_NS_SIMPLE, ADD_DITHER_TPDF_HF_F, UPDATE_ERROR_SIMPLE);
MAKE_QUANTIZE_FUNC_F (float_tpdf_hf_medium, INIT_DITHER_TPDF_HF_F,
INIT_NS_MEDIUM, ADD_NS_MEDIUM, ADD_DITHER_TPDF_HF_F, UPDATE_ERROR_MEDIUM);
MAKE_QUANTIZE_FUNC_F (float_tpdf_hf_high, INIT_DITHER_TPDF_HF_F, INIT_NS_HIGH,
ADD_NS_HIGH, ADD_DITHER_TPDF_HF_F, UPDATE_ERROR_HIGH);
static AudioConvertQuantize quantize_funcs[] = {
(AudioConvertQuantize) MAKE_QUANTIZE_FUNC_NAME (signed_none_none),
(AudioConvertQuantize) MAKE_QUANTIZE_FUNC_NAME (signed_rpdf_none),
(AudioConvertQuantize) MAKE_QUANTIZE_FUNC_NAME (signed_tpdf_none),
(AudioConvertQuantize) MAKE_QUANTIZE_FUNC_NAME (signed_tpdf_hf_none),
(AudioConvertQuantize) MAKE_QUANTIZE_FUNC_NAME (unsigned_none_none),
(AudioConvertQuantize) MAKE_QUANTIZE_FUNC_NAME (unsigned_rpdf_none),
(AudioConvertQuantize) MAKE_QUANTIZE_FUNC_NAME (unsigned_tpdf_none),
(AudioConvertQuantize) MAKE_QUANTIZE_FUNC_NAME (unsigned_tpdf_hf_none),
(AudioConvertQuantize) MAKE_QUANTIZE_FUNC_NAME (float_none_error_feedback),
(AudioConvertQuantize) MAKE_QUANTIZE_FUNC_NAME (float_none_simple),
(AudioConvertQuantize) MAKE_QUANTIZE_FUNC_NAME (float_none_medium),
(AudioConvertQuantize) MAKE_QUANTIZE_FUNC_NAME (float_none_high),
(AudioConvertQuantize) MAKE_QUANTIZE_FUNC_NAME (float_rpdf_error_feedback),
(AudioConvertQuantize) MAKE_QUANTIZE_FUNC_NAME (float_rpdf_simple),
(AudioConvertQuantize) MAKE_QUANTIZE_FUNC_NAME (float_rpdf_medium),
(AudioConvertQuantize) MAKE_QUANTIZE_FUNC_NAME (float_rpdf_high),
(AudioConvertQuantize) MAKE_QUANTIZE_FUNC_NAME (float_tpdf_error_feedback),
(AudioConvertQuantize) MAKE_QUANTIZE_FUNC_NAME (float_tpdf_simple),
(AudioConvertQuantize) MAKE_QUANTIZE_FUNC_NAME (float_tpdf_medium),
(AudioConvertQuantize) MAKE_QUANTIZE_FUNC_NAME (float_tpdf_high),
(AudioConvertQuantize) MAKE_QUANTIZE_FUNC_NAME (float_tpdf_hf_error_feedback),
(AudioConvertQuantize) MAKE_QUANTIZE_FUNC_NAME (float_tpdf_hf_simple),
(AudioConvertQuantize) MAKE_QUANTIZE_FUNC_NAME (float_tpdf_hf_medium),
(AudioConvertQuantize) MAKE_QUANTIZE_FUNC_NAME (float_tpdf_hf_high)
};
static void
gst_audio_quantize_setup_noise_shaping (AudioConvertCtx * ctx)
{
switch (ctx->ns) {
case NOISE_SHAPING_HIGH:{
ctx->error_buf = g_new0 (gdouble, ctx->out.channels * 8);
break;
}
case NOISE_SHAPING_MEDIUM:{
ctx->error_buf = g_new0 (gdouble, ctx->out.channels * 5);
break;
}
case NOISE_SHAPING_SIMPLE:{
ctx->error_buf = g_new0 (gdouble, ctx->out.channels * 2);
break;
}
case NOISE_SHAPING_ERROR_FEEDBACK:
ctx->error_buf = g_new0 (gdouble, ctx->out.channels);
break;
case NOISE_SHAPING_NONE:
default:
ctx->error_buf = NULL;
break;
}
return;
}
static void
gst_audio_quantize_free_noise_shaping (AudioConvertCtx * ctx)
{
switch (ctx->ns) {
case NOISE_SHAPING_HIGH:
case NOISE_SHAPING_MEDIUM:
case NOISE_SHAPING_SIMPLE:
case NOISE_SHAPING_ERROR_FEEDBACK:
case NOISE_SHAPING_NONE:
default:
break;
}
return;
g_free (ctx->error_buf);
ctx->error_buf = NULL;
return;
}
static void
gst_audio_quantize_setup_dither (AudioConvertCtx * ctx)
{
switch (ctx->dither) {
case DITHER_TPDF_HF:
if (ctx->out.is_int)
ctx->last_random = g_new0 (gint32, ctx->out.channels);
else
ctx->last_random = g_new0 (gdouble, ctx->out.channels);
ctx->dither_random = g_rand_new ();
break;
case DITHER_RPDF:
case DITHER_TPDF:
ctx->dither_random = g_rand_new ();
ctx->last_random = NULL;
break;
case DITHER_NONE:
default:
ctx->dither_random = NULL;
ctx->last_random = NULL;
break;
}
return;
}
static void
gst_audio_quantize_free_dither (AudioConvertCtx * ctx)
{
g_free (ctx->last_random);
if (ctx->dither_random)
g_rand_free (ctx->dither_random);
return;
}
static void
gst_audio_quantize_setup_quantize_func (AudioConvertCtx * ctx)
{
gint index = 0;
if (!ctx->out.is_int) {
ctx->quantize = NULL;
return;
}
if (ctx->ns == NOISE_SHAPING_NONE) {
index += ctx->dither;
index += (ctx->out.sign) ? 0 : 4;
} else {
index += 8 + (4 * ctx->dither);
index += ctx->ns - 1;
}
ctx->quantize = quantize_funcs[index];
}
#ifdef __SYMBIAN32__
EXPORT_C
#endif
gboolean
gst_audio_quantize_setup (AudioConvertCtx * ctx)
{
gst_audio_quantize_setup_dither (ctx);
gst_audio_quantize_setup_noise_shaping (ctx);
gst_audio_quantize_setup_quantize_func (ctx);
return TRUE;
}
#ifdef __SYMBIAN32__
EXPORT_C
#endif
void
gst_audio_quantize_free (AudioConvertCtx * ctx)
{
gst_audio_quantize_free_dither (ctx);
gst_audio_quantize_free_noise_shaping (ctx);
}