/* * This file is part of libswresample * * libswresample 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. * * libswresample 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 libswresample; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */ #if defined(TEMPLATE_DITHER_DBL) # define RENAME(N) N ## _double # define DELEM double # define CLIP(v) while(0) #elif defined(TEMPLATE_DITHER_FLT) # define RENAME(N) N ## _float # define DELEM float # define CLIP(v) while(0) #elif defined(TEMPLATE_DITHER_S32) # define RENAME(N) N ## _int32 # define DELEM int32_t # define CLIP(v) v = FFMAX(FFMIN(v, INT32_MAX), INT32_MIN) #elif defined(TEMPLATE_DITHER_S16) # define RENAME(N) N ## _int16 # define DELEM int16_t # define CLIP(v) v = FFMAX(FFMIN(v, INT16_MAX), INT16_MIN) #else ERROR #endif void RENAME(swri_noise_shaping)(SwrContext *s, AudioData *dsts, const AudioData *srcs, const AudioData *noises, int count){ int pos = s->dither.ns_pos; int i, j, ch; int taps = s->dither.ns_taps; float S = s->dither.ns_scale; float S_1 = s->dither.ns_scale_1; av_assert2((taps&3) != 2); av_assert2((taps&3) != 3 || s->dither.ns_coeffs[taps] == 0); for (ch=0; ch<srcs->ch_count; ch++) { const float *noise = ((const float *)noises->ch[ch]) + s->dither.noise_pos; const DELEM *src = (const DELEM*)srcs->ch[ch]; DELEM *dst = (DELEM*)dsts->ch[ch]; float *ns_errors = s->dither.ns_errors[ch]; const float *ns_coeffs = s->dither.ns_coeffs; pos = s->dither.ns_pos; for (i=0; i<count; i++) { double d1, d = src[i]*S_1; for(j=0; j<taps-2; j+=4) { d -= ns_coeffs[j ] * ns_errors[pos + j ] +ns_coeffs[j + 1] * ns_errors[pos + j + 1] +ns_coeffs[j + 2] * ns_errors[pos + j + 2] +ns_coeffs[j + 3] * ns_errors[pos + j + 3]; } if(j < taps) d -= ns_coeffs[j] * ns_errors[pos + j]; pos = pos ? pos - 1 : taps - 1; d1 = rint(d + noise[i]); ns_errors[pos + taps] = ns_errors[pos] = d1 - d; d1 *= S; CLIP(d1); dst[i] = d1; } } s->dither.ns_pos = pos; } #undef RENAME #undef DELEM #undef CLIP