xref: /third_party/ffmpeg/libavcodec/twinvqdec.c (revision cabdff1a)
1/*
2 * TwinVQ decoder
3 * Copyright (c) 2009 Vitor Sessak
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 <math.h>
23#include <stdint.h>
24
25#include "libavutil/channel_layout.h"
26#include "avcodec.h"
27#include "codec_internal.h"
28#include "get_bits.h"
29#include "twinvq.h"
30#include "metasound_data.h"
31#include "twinvq_data.h"
32
33static const TwinVQModeTab mode_08_08 = {
34    {
35        { 8, bark_tab_s08_64,  10, tab.fcb08s, 1, 5, tab.cb0808s0, tab.cb0808s1, 18 },
36        { 2, bark_tab_m08_256, 20, tab.fcb08m, 2, 5, tab.cb0808m0, tab.cb0808m1, 16 },
37        { 1, bark_tab_l08_512, 30, tab.fcb08l, 3, 6, tab.cb0808l0, tab.cb0808l1, 17 }
38    },
39    512, 12, ff_metasound_lsp8, 1, 5, 3, 3, tab.shape08, 8, 28, 20, 6, 40
40};
41
42static const TwinVQModeTab mode_11_08 = {
43    {
44        { 8, bark_tab_s11_64,  10, tab.fcb11s, 1, 5, tab.cb1108s0, tab.cb1108s1, 29 },
45        { 2, bark_tab_m11_256, 20, tab.fcb11m, 2, 5, tab.cb1108m0, tab.cb1108m1, 24 },
46        { 1, bark_tab_l11_512, 30, tab.fcb11l, 3, 6, tab.cb1108l0, tab.cb1108l1, 27 }
47    },
48    512, 16, ff_metasound_lsp11, 1, 6, 4, 3, tab.shape11, 9, 36, 30, 7, 90
49};
50
51static const TwinVQModeTab mode_11_10 = {
52    {
53        { 8, bark_tab_s11_64,  10, tab.fcb11s, 1, 5, tab.cb1110s0, tab.cb1110s1, 21 },
54        { 2, bark_tab_m11_256, 20, tab.fcb11m, 2, 5, tab.cb1110m0, tab.cb1110m1, 18 },
55        { 1, bark_tab_l11_512, 30, tab.fcb11l, 3, 6, tab.cb1110l0, tab.cb1110l1, 20 }
56    },
57    512, 16, ff_metasound_lsp11, 1, 6, 4, 3, tab.shape11, 9, 36, 30, 7, 90
58};
59
60static const TwinVQModeTab mode_16_16 = {
61    {
62        { 8, bark_tab_s16_128,  10, tab.fcb16s, 1, 5, tab.cb1616s0, tab.cb1616s1, 16 },
63        { 2, bark_tab_m16_512,  20, tab.fcb16m, 2, 5, tab.cb1616m0, tab.cb1616m1, 15 },
64        { 1, bark_tab_l16_1024, 30, tab.fcb16l, 3, 6, tab.cb1616l0, tab.cb1616l1, 16 }
65    },
66    1024, 16, ff_metasound_lsp16, 1, 6, 4, 3, tab.shape16, 9, 56, 60, 7, 180
67};
68
69static const TwinVQModeTab mode_22_20 = {
70    {
71        { 8, bark_tab_s22_128,  10, tab.fcb22s_1, 1, 6, tab.cb2220s0, tab.cb2220s1, 18 },
72        { 2, bark_tab_m22_512,  20, tab.fcb22m_1, 2, 6, tab.cb2220m0, tab.cb2220m1, 17 },
73        { 1, bark_tab_l22_1024, 32, tab.fcb22l_1, 4, 6, tab.cb2220l0, tab.cb2220l1, 18 }
74    },
75    1024, 16, ff_metasound_lsp22, 1, 6, 4, 3, tab.shape22_1, 9, 56, 36, 7, 144
76};
77
78static const TwinVQModeTab mode_22_24 = {
79    {
80        { 8, bark_tab_s22_128,  10, tab.fcb22s_1, 1, 6, tab.cb2224s0, tab.cb2224s1, 15 },
81        { 2, bark_tab_m22_512,  20, tab.fcb22m_1, 2, 6, tab.cb2224m0, tab.cb2224m1, 14 },
82        { 1, bark_tab_l22_1024, 32, tab.fcb22l_1, 4, 6, tab.cb2224l0, tab.cb2224l1, 15 }
83    },
84    1024, 16, ff_metasound_lsp22, 1, 6, 4, 3, tab.shape22_1, 9, 56, 36, 7, 144
85};
86
87static const TwinVQModeTab mode_22_32 = {
88    {
89        { 4, bark_tab_s22_128, 10, tab.fcb22s_2, 1, 6, tab.cb2232s0, tab.cb2232s1, 11 },
90        { 2, bark_tab_m22_256, 20, tab.fcb22m_2, 2, 6, tab.cb2232m0, tab.cb2232m1, 11 },
91        { 1, bark_tab_l22_512, 32, tab.fcb22l_2, 4, 6, tab.cb2232l0, tab.cb2232l1, 12 }
92    },
93    512, 16, tab.lsp22_2, 1, 6, 4, 4, tab.shape22_2, 9, 56, 36, 7, 72
94};
95
96static const TwinVQModeTab mode_44_40 = {
97    {
98        { 16, bark_tab_s44_128,  10, tab.fcb44s, 1, 6, tab.cb4440s0, tab.cb4440s1, 18 },
99        { 4,  bark_tab_m44_512,  20, tab.fcb44m, 2, 6, tab.cb4440m0, tab.cb4440m1, 17 },
100        { 1,  bark_tab_l44_2048, 40, tab.fcb44l, 4, 6, tab.cb4440l0, tab.cb4440l1, 17 }
101    },
102    2048, 20, ff_metasound_lsp44, 1, 6, 4, 4, tab.shape44, 9, 84, 54, 7, 432
103};
104
105static const TwinVQModeTab mode_44_48 = {
106    {
107        { 16, bark_tab_s44_128,  10, tab.fcb44s, 1, 6, tab.cb4448s0, tab.cb4448s1, 15 },
108        { 4,  bark_tab_m44_512,  20, tab.fcb44m, 2, 6, tab.cb4448m0, tab.cb4448m1, 14 },
109        { 1,  bark_tab_l44_2048, 40, tab.fcb44l, 4, 6, tab.cb4448l0, tab.cb4448l1, 14 }
110    },
111    2048, 20, ff_metasound_lsp44, 1, 6, 4, 4, tab.shape44, 9, 84, 54, 7, 432
112};
113
114/**
115 * Evaluate a * b / 400 rounded to the nearest integer. When, for example,
116 * a * b == 200 and the nearest integer is ill-defined, use a table to emulate
117 * the following broken float-based implementation used by the binary decoder:
118 *
119 * @code
120 * static int very_broken_op(int a, int b)
121 * {
122 *    static float test; // Ugh, force gcc to do the division first...
123 *
124 *    test = a / 400.0;
125 *    return b * test + 0.5;
126 * }
127 * @endcode
128 *
129 * @note if this function is replaced by just ROUNDED_DIV(a * b, 400.0), the
130 * stddev between the original file (before encoding with Yamaha encoder) and
131 * the decoded output increases, which leads one to believe that the encoder
132 * expects exactly this broken calculation.
133 */
134static int very_broken_op(int a, int b)
135{
136    int x = a * b + 200;
137    int size;
138    const uint8_t *rtab;
139
140    if (x % 400 || b % 5)
141        return x / 400;
142
143    x /= 400;
144
145    size = tabs[b / 5].size;
146    rtab = tabs[b / 5].tab;
147    return x - rtab[size * av_log2(2 * (x - 1) / size) + (x - 1) % size];
148}
149
150/**
151 * Sum to data a periodic peak of a given period, width and shape.
152 *
153 * @param period the period of the peak divided by 400.0
154 */
155static void add_peak(int period, int width, const float *shape,
156                     float ppc_gain, float *speech, int len)
157{
158    int i, j;
159
160    const float *shape_end = shape + len;
161    int center;
162
163    // First peak centered around zero
164    for (i = 0; i < width / 2; i++)
165        speech[i] += ppc_gain * *shape++;
166
167    for (i = 1; i < ROUNDED_DIV(len, width); i++) {
168        center = very_broken_op(period, i);
169        for (j = -width / 2; j < (width + 1) / 2; j++)
170            speech[j + center] += ppc_gain * *shape++;
171    }
172
173    // For the last block, be careful not to go beyond the end of the buffer
174    center = very_broken_op(period, i);
175    for (j = -width / 2; j < (width + 1) / 2 && shape < shape_end; j++)
176        speech[j + center] += ppc_gain * *shape++;
177}
178
179static void decode_ppc(TwinVQContext *tctx, int period_coef, int g_coef,
180                       const float *shape, float *speech)
181{
182    const TwinVQModeTab *mtab = tctx->mtab;
183    int isampf = tctx->avctx->sample_rate /  1000;
184    int ibps   = tctx->avctx->bit_rate    / (1000 * tctx->avctx->ch_layout.nb_channels);
185    int min_period   = ROUNDED_DIV(40 * 2 * mtab->size, isampf);
186    int max_period   = ROUNDED_DIV(40 * 2 * mtab->size * 6, isampf);
187    int period_range = max_period - min_period;
188    float pgain_step = 25000.0 / ((1 << mtab->pgain_bit) - 1);
189    float ppc_gain   = 1.0 / 8192 *
190                       twinvq_mulawinv(pgain_step * g_coef +
191                                           pgain_step / 2,
192                                       25000.0, TWINVQ_PGAIN_MU);
193
194    // This is actually the period multiplied by 400. It is just linearly coded
195    // between its maximum and minimum value.
196    int period = min_period +
197                 ROUNDED_DIV(period_coef * period_range,
198                             (1 << mtab->ppc_period_bit) - 1);
199    int width;
200
201    if (isampf == 22 && ibps == 32) {
202        // For some unknown reason, NTT decided to code this case differently...
203        width = ROUNDED_DIV((period + 800) * mtab->peak_per2wid,
204                            400 * mtab->size);
205    } else
206        width = period * mtab->peak_per2wid / (400 * mtab->size);
207
208    add_peak(period, width, shape, ppc_gain, speech, mtab->ppc_shape_len);
209}
210
211static void dec_bark_env(TwinVQContext *tctx, const uint8_t *in, int use_hist,
212                         int ch, float *out, float gain,
213                         enum TwinVQFrameType ftype)
214{
215    const TwinVQModeTab *mtab = tctx->mtab;
216    int i, j;
217    float *hist     = tctx->bark_hist[ftype][ch];
218    float val       = ((const float []) { 0.4, 0.35, 0.28 })[ftype];
219    int bark_n_coef = mtab->fmode[ftype].bark_n_coef;
220    int fw_cb_len   = mtab->fmode[ftype].bark_env_size / bark_n_coef;
221    int idx         = 0;
222
223    for (i = 0; i < fw_cb_len; i++)
224        for (j = 0; j < bark_n_coef; j++, idx++) {
225            float tmp2 = mtab->fmode[ftype].bark_cb[fw_cb_len * in[j] + i] *
226                         (1.0 / 4096);
227            float st   = use_hist ? (1.0 - val) * tmp2 + val * hist[idx] + 1.0
228                                  : tmp2 + 1.0;
229
230            hist[idx] = tmp2;
231            if (st < -1.0)
232                st = 1.0;
233
234            twinvq_memset_float(out, st * gain, mtab->fmode[ftype].bark_tab[idx]);
235            out += mtab->fmode[ftype].bark_tab[idx];
236        }
237}
238
239static void read_cb_data(TwinVQContext *tctx, GetBitContext *gb,
240                         uint8_t *dst, enum TwinVQFrameType ftype)
241{
242    int i;
243
244    for (i = 0; i < tctx->n_div[ftype]; i++) {
245        int bs_second_part = (i >= tctx->bits_main_spec_change[ftype]);
246
247        *dst++ = get_bits(gb, tctx->bits_main_spec[0][ftype][bs_second_part]);
248        *dst++ = get_bits(gb, tctx->bits_main_spec[1][ftype][bs_second_part]);
249    }
250}
251
252static int twinvq_read_bitstream(AVCodecContext *avctx, TwinVQContext *tctx,
253                                 const uint8_t *buf, int buf_size)
254{
255    TwinVQFrameData     *bits = &tctx->bits[0];
256    const TwinVQModeTab *mtab = tctx->mtab;
257    int channels              = tctx->avctx->ch_layout.nb_channels;
258    int sub;
259    GetBitContext gb;
260    int i, j, k, ret;
261
262    if ((ret = init_get_bits8(&gb, buf, buf_size)) < 0)
263        return ret;
264    skip_bits(&gb, get_bits(&gb, 8));
265
266    bits->window_type = get_bits(&gb, TWINVQ_WINDOW_TYPE_BITS);
267
268    if (bits->window_type > 8) {
269        av_log(avctx, AV_LOG_ERROR, "Invalid window type, broken sample?\n");
270        return AVERROR_INVALIDDATA;
271    }
272
273    bits->ftype = ff_twinvq_wtype_to_ftype_table[tctx->bits[0].window_type];
274
275    sub = mtab->fmode[bits->ftype].sub;
276
277    read_cb_data(tctx, &gb, bits->main_coeffs, bits->ftype);
278
279    for (i = 0; i < channels; i++)
280        for (j = 0; j < sub; j++)
281            for (k = 0; k < mtab->fmode[bits->ftype].bark_n_coef; k++)
282                bits->bark1[i][j][k] =
283                    get_bits(&gb, mtab->fmode[bits->ftype].bark_n_bit);
284
285    for (i = 0; i < channels; i++)
286        for (j = 0; j < sub; j++)
287            bits->bark_use_hist[i][j] = get_bits1(&gb);
288
289    if (bits->ftype == TWINVQ_FT_LONG) {
290        for (i = 0; i < channels; i++)
291            bits->gain_bits[i] = get_bits(&gb, TWINVQ_GAIN_BITS);
292    } else {
293        for (i = 0; i < channels; i++) {
294            bits->gain_bits[i] = get_bits(&gb, TWINVQ_GAIN_BITS);
295            for (j = 0; j < sub; j++)
296                bits->sub_gain_bits[i * sub + j] = get_bits(&gb,
297                                                       TWINVQ_SUB_GAIN_BITS);
298        }
299    }
300
301    for (i = 0; i < channels; i++) {
302        bits->lpc_hist_idx[i] = get_bits(&gb, mtab->lsp_bit0);
303        bits->lpc_idx1[i]     = get_bits(&gb, mtab->lsp_bit1);
304
305        for (j = 0; j < mtab->lsp_split; j++)
306            bits->lpc_idx2[i][j] = get_bits(&gb, mtab->lsp_bit2);
307    }
308
309    if (bits->ftype == TWINVQ_FT_LONG) {
310        read_cb_data(tctx, &gb, bits->ppc_coeffs, 3);
311        for (i = 0; i < channels; i++) {
312            bits->p_coef[i] = get_bits(&gb, mtab->ppc_period_bit);
313            bits->g_coef[i] = get_bits(&gb, mtab->pgain_bit);
314        }
315    }
316
317    return (get_bits_count(&gb) + 7) / 8;
318}
319
320static av_cold int twinvq_decode_init(AVCodecContext *avctx)
321{
322    int isampf, ibps, channels;
323    TwinVQContext *tctx = avctx->priv_data;
324
325    if (!avctx->extradata || avctx->extradata_size < 12) {
326        av_log(avctx, AV_LOG_ERROR, "Missing or incomplete extradata\n");
327        return AVERROR_INVALIDDATA;
328    }
329    channels        = AV_RB32(avctx->extradata)     + 1;
330    avctx->bit_rate = AV_RB32(avctx->extradata + 4) * 1000;
331    isampf          = AV_RB32(avctx->extradata + 8);
332
333    if (isampf < 8 || isampf > 44) {
334        av_log(avctx, AV_LOG_ERROR, "Unsupported sample rate\n");
335        return AVERROR_INVALIDDATA;
336    }
337    switch (isampf) {
338    case 44:
339        avctx->sample_rate = 44100;
340        break;
341    case 22:
342        avctx->sample_rate = 22050;
343        break;
344    case 11:
345        avctx->sample_rate = 11025;
346        break;
347    default:
348        avctx->sample_rate = isampf * 1000;
349        break;
350    }
351
352    if (channels <= 0 || channels > TWINVQ_CHANNELS_MAX) {
353        av_log(avctx, AV_LOG_ERROR, "Unsupported number of channels: %i\n",
354               channels);
355        return -1;
356    }
357    av_channel_layout_uninit(&avctx->ch_layout);
358    av_channel_layout_default(&avctx->ch_layout, channels);
359
360    ibps = avctx->bit_rate / (1000 * channels);
361    if (ibps < 8 || ibps > 48) {
362        av_log(avctx, AV_LOG_ERROR, "Bad bitrate per channel value %d\n", ibps);
363        return AVERROR_INVALIDDATA;
364    }
365
366    switch ((isampf << 8) + ibps) {
367    case (8 << 8) + 8:
368        tctx->mtab = &mode_08_08;
369        break;
370    case (11 << 8) + 8:
371        tctx->mtab = &mode_11_08;
372        break;
373    case (11 << 8) + 10:
374        tctx->mtab = &mode_11_10;
375        break;
376    case (16 << 8) + 16:
377        tctx->mtab = &mode_16_16;
378        break;
379    case (22 << 8) + 20:
380        tctx->mtab = &mode_22_20;
381        break;
382    case (22 << 8) + 24:
383        tctx->mtab = &mode_22_24;
384        break;
385    case (22 << 8) + 32:
386        tctx->mtab = &mode_22_32;
387        break;
388    case (44 << 8) + 40:
389        tctx->mtab = &mode_44_40;
390        break;
391    case (44 << 8) + 48:
392        tctx->mtab = &mode_44_48;
393        break;
394    default:
395        av_log(avctx, AV_LOG_ERROR,
396               "This version does not support %d kHz - %d kbit/s/ch mode.\n",
397               isampf, isampf);
398        return -1;
399    }
400
401    tctx->codec          = TWINVQ_CODEC_VQF;
402    tctx->read_bitstream = twinvq_read_bitstream;
403    tctx->dec_bark_env   = dec_bark_env;
404    tctx->decode_ppc     = decode_ppc;
405    tctx->frame_size     = avctx->bit_rate * tctx->mtab->size
406                                           / avctx->sample_rate + 8;
407    tctx->is_6kbps       = 0;
408    if (avctx->block_align && avctx->block_align * 8LL / tctx->frame_size > 1) {
409        av_log(avctx, AV_LOG_ERROR,
410               "VQF TwinVQ should have only one frame per packet\n");
411        return AVERROR_INVALIDDATA;
412    }
413
414    return ff_twinvq_decode_init(avctx);
415}
416
417const FFCodec ff_twinvq_decoder = {
418    .p.name         = "twinvq",
419    .p.long_name    = NULL_IF_CONFIG_SMALL("VQF TwinVQ"),
420    .p.type         = AVMEDIA_TYPE_AUDIO,
421    .p.id           = AV_CODEC_ID_TWINVQ,
422    .priv_data_size = sizeof(TwinVQContext),
423    .init           = twinvq_decode_init,
424    .close          = ff_twinvq_decode_close,
425    FF_CODEC_DECODE_CB(ff_twinvq_decode_frame),
426    .p.capabilities = AV_CODEC_CAP_DR1 | AV_CODEC_CAP_CHANNEL_CONF,
427    .p.sample_fmts  = (const enum AVSampleFormat[]) { AV_SAMPLE_FMT_FLTP,
428                                                      AV_SAMPLE_FMT_NONE },
429    .caps_internal  = FF_CODEC_CAP_INIT_THREADSAFE | FF_CODEC_CAP_INIT_CLEANUP,
430};
431