1/*
2 * Copyright (C) 2011 Michael Niedermayer (michaelni@gmx.at)
3 * Copyright (c) 2012 Justin Ruggles <justin.ruggles@gmail.com>
4 *
5 * This file is part of FFmpeg.
6 *
7 * FFmpeg is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU Lesser General Public
9 * License as published by the Free Software Foundation; either
10 * version 2.1 of the License, or (at your option) any later version.
11 *
12 * FFmpeg is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
15 * Lesser General Public License for more details.
16 *
17 * You should have received a copy of the GNU Lesser General Public
18 * License along with FFmpeg; if not, write to the Free Software
19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20 */
21
22#include <stdint.h>
23
24#include "libavutil/common.h"
25#include "libavutil/libm.h"
26#include "libavutil/samplefmt.h"
27#include "avresample.h"
28#include "internal.h"
29#include "audio_data.h"
30#include "audio_mix.h"
31
32/* channel positions */
33#define FRONT_LEFT              0
34#define FRONT_RIGHT             1
35#define FRONT_CENTER            2
36#define LOW_FREQUENCY           3
37#define BACK_LEFT               4
38#define BACK_RIGHT              5
39#define FRONT_LEFT_OF_CENTER    6
40#define FRONT_RIGHT_OF_CENTER   7
41#define BACK_CENTER             8
42#define SIDE_LEFT               9
43#define SIDE_RIGHT             10
44#define TOP_CENTER             11
45#define TOP_FRONT_LEFT         12
46#define TOP_FRONT_CENTER       13
47#define TOP_FRONT_RIGHT        14
48#define TOP_BACK_LEFT          15
49#define TOP_BACK_CENTER        16
50#define TOP_BACK_RIGHT         17
51#define STEREO_LEFT            29
52#define STEREO_RIGHT           30
53#define WIDE_LEFT              31
54#define WIDE_RIGHT             32
55#define SURROUND_DIRECT_LEFT   33
56#define SURROUND_DIRECT_RIGHT  34
57#define LOW_FREQUENCY_2        35
58
59#define SQRT3_2      1.22474487139158904909  /* sqrt(3/2) */
60
61static av_always_inline int even(uint64_t layout)
62{
63    return (!layout || (layout & (layout - 1)));
64}
65
66static int sane_layout(uint64_t layout)
67{
68    /* check that there is at least 1 front speaker */
69    if (!(layout & AV_CH_LAYOUT_SURROUND))
70        return 0;
71
72    /* check for left/right symmetry */
73    if (!even(layout & (AV_CH_FRONT_LEFT           | AV_CH_FRONT_RIGHT))           ||
74        !even(layout & (AV_CH_SIDE_LEFT            | AV_CH_SIDE_RIGHT))            ||
75        !even(layout & (AV_CH_BACK_LEFT            | AV_CH_BACK_RIGHT))            ||
76        !even(layout & (AV_CH_FRONT_LEFT_OF_CENTER | AV_CH_FRONT_RIGHT_OF_CENTER)) ||
77        !even(layout & (AV_CH_TOP_FRONT_LEFT       | AV_CH_TOP_FRONT_RIGHT))       ||
78        !even(layout & (AV_CH_TOP_BACK_LEFT        | AV_CH_TOP_BACK_RIGHT))        ||
79        !even(layout & (AV_CH_STEREO_LEFT          | AV_CH_STEREO_RIGHT))          ||
80        !even(layout & (AV_CH_WIDE_LEFT            | AV_CH_WIDE_RIGHT))            ||
81        !even(layout & (AV_CH_SURROUND_DIRECT_LEFT | AV_CH_SURROUND_DIRECT_RIGHT)))
82        return 0;
83
84    return 1;
85}
86
87int avresample_build_matrix(uint64_t in_layout, uint64_t out_layout,
88                            double center_mix_level, double surround_mix_level,
89                            double lfe_mix_level, int normalize,
90                            double *matrix_out, int stride,
91                            enum AVMatrixEncoding matrix_encoding)
92{
93    int i, j, out_i, out_j;
94    double matrix[64][64] = {{0}};
95    int64_t unaccounted;
96    double maxcoef = 0;
97    int in_channels, out_channels;
98
99    if ((out_layout & AV_CH_LAYOUT_STEREO_DOWNMIX) == AV_CH_LAYOUT_STEREO_DOWNMIX) {
100        out_layout = AV_CH_LAYOUT_STEREO;
101    }
102
103    unaccounted = in_layout & ~out_layout;
104
105    in_channels  = av_get_channel_layout_nb_channels( in_layout);
106    out_channels = av_get_channel_layout_nb_channels(out_layout);
107
108    memset(matrix_out, 0, out_channels * stride * sizeof(*matrix_out));
109
110    /* check if layouts are supported */
111    if (!in_layout || in_channels > AVRESAMPLE_MAX_CHANNELS)
112        return AVERROR(EINVAL);
113    if (!out_layout || out_channels > AVRESAMPLE_MAX_CHANNELS)
114        return AVERROR(EINVAL);
115
116    /* check if layouts are unbalanced or abnormal */
117    if (!sane_layout(in_layout) || !sane_layout(out_layout))
118        return AVERROR_PATCHWELCOME;
119
120    /* route matching input/output channels */
121    for (i = 0; i < 64; i++) {
122        if (in_layout & out_layout & (1ULL << i))
123            matrix[i][i] = 1.0;
124    }
125
126    /* mix front center to front left/right */
127    if (unaccounted & AV_CH_FRONT_CENTER) {
128        if ((out_layout & AV_CH_LAYOUT_STEREO) == AV_CH_LAYOUT_STEREO) {
129            if ((in_layout & AV_CH_LAYOUT_STEREO) == AV_CH_LAYOUT_STEREO) {
130                matrix[FRONT_LEFT ][FRONT_CENTER] += center_mix_level;
131                matrix[FRONT_RIGHT][FRONT_CENTER] += center_mix_level;
132            } else {
133                matrix[FRONT_LEFT ][FRONT_CENTER] += M_SQRT1_2;
134                matrix[FRONT_RIGHT][FRONT_CENTER] += M_SQRT1_2;
135            }
136        } else
137            return AVERROR_PATCHWELCOME;
138    }
139    /* mix front left/right to center */
140    if (unaccounted & AV_CH_LAYOUT_STEREO) {
141        if (out_layout & AV_CH_FRONT_CENTER) {
142            matrix[FRONT_CENTER][FRONT_LEFT ] += M_SQRT1_2;
143            matrix[FRONT_CENTER][FRONT_RIGHT] += M_SQRT1_2;
144            /* mix left/right/center to center */
145            if (in_layout & AV_CH_FRONT_CENTER)
146                matrix[FRONT_CENTER][FRONT_CENTER] = center_mix_level * M_SQRT2;
147        } else
148            return AVERROR_PATCHWELCOME;
149    }
150    /* mix back center to back, side, or front */
151    if (unaccounted & AV_CH_BACK_CENTER) {
152        if (out_layout & AV_CH_BACK_LEFT) {
153            matrix[BACK_LEFT ][BACK_CENTER] += M_SQRT1_2;
154            matrix[BACK_RIGHT][BACK_CENTER] += M_SQRT1_2;
155        } else if (out_layout & AV_CH_SIDE_LEFT) {
156            matrix[SIDE_LEFT ][BACK_CENTER] += M_SQRT1_2;
157            matrix[SIDE_RIGHT][BACK_CENTER] += M_SQRT1_2;
158        } else if (out_layout & AV_CH_FRONT_LEFT) {
159            if (matrix_encoding == AV_MATRIX_ENCODING_DOLBY ||
160                matrix_encoding == AV_MATRIX_ENCODING_DPLII) {
161                if (unaccounted & (AV_CH_BACK_LEFT | AV_CH_SIDE_LEFT)) {
162                    matrix[FRONT_LEFT ][BACK_CENTER] -= surround_mix_level * M_SQRT1_2;
163                    matrix[FRONT_RIGHT][BACK_CENTER] += surround_mix_level * M_SQRT1_2;
164                } else {
165                    matrix[FRONT_LEFT ][BACK_CENTER] -= surround_mix_level;
166                    matrix[FRONT_RIGHT][BACK_CENTER] += surround_mix_level;
167                }
168            } else {
169                matrix[FRONT_LEFT ][BACK_CENTER] += surround_mix_level * M_SQRT1_2;
170                matrix[FRONT_RIGHT][BACK_CENTER] += surround_mix_level * M_SQRT1_2;
171            }
172        } else if (out_layout & AV_CH_FRONT_CENTER) {
173            matrix[FRONT_CENTER][BACK_CENTER] += surround_mix_level * M_SQRT1_2;
174        } else
175            return AVERROR_PATCHWELCOME;
176    }
177    /* mix back left/right to back center, side, or front */
178    if (unaccounted & AV_CH_BACK_LEFT) {
179        if (out_layout & AV_CH_BACK_CENTER) {
180            matrix[BACK_CENTER][BACK_LEFT ] += M_SQRT1_2;
181            matrix[BACK_CENTER][BACK_RIGHT] += M_SQRT1_2;
182        } else if (out_layout & AV_CH_SIDE_LEFT) {
183            /* if side channels do not exist in the input, just copy back
184               channels to side channels, otherwise mix back into side */
185            if (in_layout & AV_CH_SIDE_LEFT) {
186                matrix[SIDE_LEFT ][BACK_LEFT ] += M_SQRT1_2;
187                matrix[SIDE_RIGHT][BACK_RIGHT] += M_SQRT1_2;
188            } else {
189                matrix[SIDE_LEFT ][BACK_LEFT ] += 1.0;
190                matrix[SIDE_RIGHT][BACK_RIGHT] += 1.0;
191            }
192        } else if (out_layout & AV_CH_FRONT_LEFT) {
193            if (matrix_encoding == AV_MATRIX_ENCODING_DOLBY) {
194                matrix[FRONT_LEFT ][BACK_LEFT ] -= surround_mix_level * M_SQRT1_2;
195                matrix[FRONT_LEFT ][BACK_RIGHT] -= surround_mix_level * M_SQRT1_2;
196                matrix[FRONT_RIGHT][BACK_LEFT ] += surround_mix_level * M_SQRT1_2;
197                matrix[FRONT_RIGHT][BACK_RIGHT] += surround_mix_level * M_SQRT1_2;
198            } else if (matrix_encoding == AV_MATRIX_ENCODING_DPLII) {
199                matrix[FRONT_LEFT ][BACK_LEFT ] -= surround_mix_level * SQRT3_2;
200                matrix[FRONT_LEFT ][BACK_RIGHT] -= surround_mix_level * M_SQRT1_2;
201                matrix[FRONT_RIGHT][BACK_LEFT ] += surround_mix_level * M_SQRT1_2;
202                matrix[FRONT_RIGHT][BACK_RIGHT] += surround_mix_level * SQRT3_2;
203            } else {
204                matrix[FRONT_LEFT ][BACK_LEFT ] += surround_mix_level;
205                matrix[FRONT_RIGHT][BACK_RIGHT] += surround_mix_level;
206            }
207        } else if (out_layout & AV_CH_FRONT_CENTER) {
208            matrix[FRONT_CENTER][BACK_LEFT ] += surround_mix_level * M_SQRT1_2;
209            matrix[FRONT_CENTER][BACK_RIGHT] += surround_mix_level * M_SQRT1_2;
210        } else
211            return AVERROR_PATCHWELCOME;
212    }
213    /* mix side left/right into back or front */
214    if (unaccounted & AV_CH_SIDE_LEFT) {
215        if (out_layout & AV_CH_BACK_LEFT) {
216            /* if back channels do not exist in the input, just copy side
217               channels to back channels, otherwise mix side into back */
218            if (in_layout & AV_CH_BACK_LEFT) {
219                matrix[BACK_LEFT ][SIDE_LEFT ] += M_SQRT1_2;
220                matrix[BACK_RIGHT][SIDE_RIGHT] += M_SQRT1_2;
221            } else {
222                matrix[BACK_LEFT ][SIDE_LEFT ] += 1.0;
223                matrix[BACK_RIGHT][SIDE_RIGHT] += 1.0;
224            }
225        } else if (out_layout & AV_CH_BACK_CENTER) {
226            matrix[BACK_CENTER][SIDE_LEFT ] += M_SQRT1_2;
227            matrix[BACK_CENTER][SIDE_RIGHT] += M_SQRT1_2;
228        } else if (out_layout & AV_CH_FRONT_LEFT) {
229            if (matrix_encoding == AV_MATRIX_ENCODING_DOLBY) {
230                matrix[FRONT_LEFT ][SIDE_LEFT ] -= surround_mix_level * M_SQRT1_2;
231                matrix[FRONT_LEFT ][SIDE_RIGHT] -= surround_mix_level * M_SQRT1_2;
232                matrix[FRONT_RIGHT][SIDE_LEFT ] += surround_mix_level * M_SQRT1_2;
233                matrix[FRONT_RIGHT][SIDE_RIGHT] += surround_mix_level * M_SQRT1_2;
234            } else if (matrix_encoding == AV_MATRIX_ENCODING_DPLII) {
235                matrix[FRONT_LEFT ][SIDE_LEFT ] -= surround_mix_level * SQRT3_2;
236                matrix[FRONT_LEFT ][SIDE_RIGHT] -= surround_mix_level * M_SQRT1_2;
237                matrix[FRONT_RIGHT][SIDE_LEFT ] += surround_mix_level * M_SQRT1_2;
238                matrix[FRONT_RIGHT][SIDE_RIGHT] += surround_mix_level * SQRT3_2;
239            } else {
240                matrix[FRONT_LEFT ][SIDE_LEFT ] += surround_mix_level;
241                matrix[FRONT_RIGHT][SIDE_RIGHT] += surround_mix_level;
242            }
243        } else if (out_layout & AV_CH_FRONT_CENTER) {
244            matrix[FRONT_CENTER][SIDE_LEFT ] += surround_mix_level * M_SQRT1_2;
245            matrix[FRONT_CENTER][SIDE_RIGHT] += surround_mix_level * M_SQRT1_2;
246        } else
247            return AVERROR_PATCHWELCOME;
248    }
249    /* mix left-of-center/right-of-center into front left/right or center */
250    if (unaccounted & AV_CH_FRONT_LEFT_OF_CENTER) {
251        if (out_layout & AV_CH_FRONT_LEFT) {
252            matrix[FRONT_LEFT ][FRONT_LEFT_OF_CENTER ] += 1.0;
253            matrix[FRONT_RIGHT][FRONT_RIGHT_OF_CENTER] += 1.0;
254        } else if (out_layout & AV_CH_FRONT_CENTER) {
255            matrix[FRONT_CENTER][FRONT_LEFT_OF_CENTER ] += M_SQRT1_2;
256            matrix[FRONT_CENTER][FRONT_RIGHT_OF_CENTER] += M_SQRT1_2;
257        } else
258            return AVERROR_PATCHWELCOME;
259    }
260    /* mix LFE into front left/right or center */
261    if (unaccounted & AV_CH_LOW_FREQUENCY) {
262        if (out_layout & AV_CH_FRONT_CENTER) {
263            matrix[FRONT_CENTER][LOW_FREQUENCY] += lfe_mix_level;
264        } else if (out_layout & AV_CH_FRONT_LEFT) {
265            matrix[FRONT_LEFT ][LOW_FREQUENCY] += lfe_mix_level * M_SQRT1_2;
266            matrix[FRONT_RIGHT][LOW_FREQUENCY] += lfe_mix_level * M_SQRT1_2;
267        } else
268            return AVERROR_PATCHWELCOME;
269    }
270
271    /* transfer internal matrix to output matrix and calculate maximum
272       per-channel coefficient sum */
273    for (out_i = i = 0; out_i < out_channels && i < 64; i++) {
274        double sum = 0;
275        for (out_j = j = 0; out_j < in_channels && j < 64; j++) {
276            matrix_out[out_i * stride + out_j] = matrix[i][j];
277            sum += fabs(matrix[i][j]);
278            if (in_layout & (1ULL << j))
279                out_j++;
280        }
281        maxcoef = FFMAX(maxcoef, sum);
282        if (out_layout & (1ULL << i))
283            out_i++;
284    }
285
286    /* normalize */
287    if (normalize && maxcoef > 1.0) {
288        for (i = 0; i < out_channels; i++)
289            for (j = 0; j < in_channels; j++)
290                matrix_out[i * stride + j] /= maxcoef;
291    }
292
293    return 0;
294}
295