/* GStreamer * Copyright (C) 2007 Sebastian Dröge * * 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., 51 Franklin St, Fifth Floor, * Boston, MA 02110-1301, 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 #include #include #include "audioconvert.h" #include "gstaudioquantize.h" #include "gstfastrandom.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.users.qwest.net/~volt42/cadenzarecording/DitherExplained.pdf 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)); /* Assuming dither == 2^n, * returns one of 2^(n+1) possible random values: * -dither <= retval < dither */ #define RANDOM_INT_DITHER(dither) \ (- dither + (gst_fast_random_int32 () & ((dither << 1) - 1))) #define ADD_DITHER_RPDF_I() \ rand = bias + RANDOM_INT_DITHER(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 += gst_fast_random_double_range (- dither, dither); #define INIT_DITHER_TPDF_I() \ gint32 rand; \ gint32 dither = (1<<(scale - 1)); #define ADD_DITHER_TPDF_I() \ rand = bias + RANDOM_INT_DITHER(dither) \ + RANDOM_INT_DITHER(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_TPDF_F() \ gdouble dither = 1.0/(1U<<(32 - scale)); #define ADD_DITHER_TPDF_F() \ tmp += gst_fast_random_double_range (- dither, dither) \ + gst_fast_random_double_range (- dither, dither); #define INIT_DITHER_TPDF_HF_I() \ gint32 rand; \ gint32 dither = (1<<(scale-1)); \ gint32 *last_random = (gint32 *) ctx->last_random, tmp_rand; #define ADD_DITHER_TPDF_HF_I() \ tmp_rand = RANDOM_INT_DITHER(dither); \ rand = bias + 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 = gst_fast_random_double_range (- 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 const 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; } 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 (GST_AUDIO_FORMAT_INFO_IS_INTEGER (ctx->out.finfo)) ctx->last_random = g_new0 (gint32, ctx->out.channels); else ctx->last_random = g_new0 (gdouble, ctx->out.channels); break; case DITHER_RPDF: case DITHER_TPDF: ctx->last_random = NULL; break; case DITHER_NONE: default: ctx->last_random = NULL; break; } return; } static void gst_audio_quantize_free_dither (AudioConvertCtx * ctx) { g_free (ctx->last_random); return; } static void gst_audio_quantize_setup_quantize_func (AudioConvertCtx * ctx) { gint index = 0; if (!GST_AUDIO_FORMAT_INFO_IS_INTEGER (ctx->out.finfo)) { ctx->quantize = NULL; return; } if (ctx->ns == NOISE_SHAPING_NONE) { index += ctx->dither; index += GST_AUDIO_FORMAT_INFO_IS_SIGNED (ctx->out.finfo) ? 0 : 4; } else { index += 8 + (4 * ctx->dither); index += ctx->ns - 1; } ctx->quantize = quantize_funcs[index]; } 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; } void gst_audio_quantize_free (AudioConvertCtx * ctx) { gst_audio_quantize_free_dither (ctx); gst_audio_quantize_free_noise_shaping (ctx); }