blob: 1f535de3dc59c228618749ec8c29f080270e9a47
| 1 | /* |
| 2 | * This file is part of libswresample |
| 3 | * |
| 4 | * libswresample is free software; you can redistribute it and/or |
| 5 | * modify it under the terms of the GNU Lesser General Public |
| 6 | * License as published by the Free Software Foundation; either |
| 7 | * version 2.1 of the License, or (at your option) any later version. |
| 8 | * |
| 9 | * libswresample is distributed in the hope that it will be useful, |
| 10 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 11 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 12 | * Lesser General Public License for more details. |
| 13 | * |
| 14 | * You should have received a copy of the GNU Lesser General Public |
| 15 | * License along with libswresample; if not, write to the Free Software |
| 16 | * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA |
| 17 | */ |
| 18 | |
| 19 | #if defined(TEMPLATE_DITHER_DBL) |
| 20 | # define RENAME(N) N ## _double |
| 21 | # define DELEM double |
| 22 | # define CLIP(v) while(0) |
| 23 | |
| 24 | #elif defined(TEMPLATE_DITHER_FLT) |
| 25 | # define RENAME(N) N ## _float |
| 26 | # define DELEM float |
| 27 | # define CLIP(v) while(0) |
| 28 | |
| 29 | #elif defined(TEMPLATE_DITHER_S32) |
| 30 | # define RENAME(N) N ## _int32 |
| 31 | # define DELEM int32_t |
| 32 | # define CLIP(v) v = FFMAX(FFMIN(v, INT32_MAX), INT32_MIN) |
| 33 | |
| 34 | #elif defined(TEMPLATE_DITHER_S16) |
| 35 | # define RENAME(N) N ## _int16 |
| 36 | # define DELEM int16_t |
| 37 | # define CLIP(v) v = FFMAX(FFMIN(v, INT16_MAX), INT16_MIN) |
| 38 | |
| 39 | #else |
| 40 | ERROR |
| 41 | #endif |
| 42 | |
| 43 | void RENAME(swri_noise_shaping)(SwrContext *s, AudioData *dsts, const AudioData *srcs, const AudioData *noises, int count){ |
| 44 | int pos = s->dither.ns_pos; |
| 45 | int i, j, ch; |
| 46 | int taps = s->dither.ns_taps; |
| 47 | float S = s->dither.ns_scale; |
| 48 | float S_1 = s->dither.ns_scale_1; |
| 49 | |
| 50 | av_assert2((taps&3) != 2); |
| 51 | av_assert2((taps&3) != 3 || s->dither.ns_coeffs[taps] == 0); |
| 52 | |
| 53 | for (ch=0; ch<srcs->ch_count; ch++) { |
| 54 | const float *noise = ((const float *)noises->ch[ch]) + s->dither.noise_pos; |
| 55 | const DELEM *src = (const DELEM*)srcs->ch[ch]; |
| 56 | DELEM *dst = (DELEM*)dsts->ch[ch]; |
| 57 | float *ns_errors = s->dither.ns_errors[ch]; |
| 58 | const float *ns_coeffs = s->dither.ns_coeffs; |
| 59 | pos = s->dither.ns_pos; |
| 60 | for (i=0; i<count; i++) { |
| 61 | double d1, d = src[i]*S_1; |
| 62 | for(j=0; j<taps-2; j+=4) { |
| 63 | d -= ns_coeffs[j ] * ns_errors[pos + j ] |
| 64 | +ns_coeffs[j + 1] * ns_errors[pos + j + 1] |
| 65 | +ns_coeffs[j + 2] * ns_errors[pos + j + 2] |
| 66 | +ns_coeffs[j + 3] * ns_errors[pos + j + 3]; |
| 67 | } |
| 68 | if(j < taps) |
| 69 | d -= ns_coeffs[j] * ns_errors[pos + j]; |
| 70 | pos = pos ? pos - 1 : taps - 1; |
| 71 | d1 = rint(d + noise[i]); |
| 72 | ns_errors[pos + taps] = ns_errors[pos] = d1 - d; |
| 73 | d1 *= S; |
| 74 | CLIP(d1); |
| 75 | dst[i] = d1; |
| 76 | } |
| 77 | } |
| 78 | |
| 79 | s->dither.ns_pos = pos; |
| 80 | } |
| 81 | |
| 82 | #undef RENAME |
| 83 | #undef DELEM |
| 84 | #undef CLIP |
| 85 |