xref: /third_party/ffmpeg/libavcodec/metasound.c (revision cabdff1a)
1/*
2 * Voxware MetaSound decoder
3 * Copyright (c) 2013 Konstantin Shishkov
4 * based on TwinVQ decoder
5 * Copyright (c) 2009 Vitor Sessak
6 *
7 * This file is part of FFmpeg.
8 *
9 * FFmpeg is free software; you can redistribute it and/or
10 * modify it under the terms of the GNU Lesser General Public
11 * License as published by the Free Software Foundation; either
12 * version 2.1 of the License, or (at your option) any later version.
13 *
14 * FFmpeg is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
17 * Lesser General Public License for more details.
18 *
19 * You should have received a copy of the GNU Lesser General Public
20 * License along with FFmpeg; if not, write to the Free Software
21 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
22 */
23
24#include <inttypes.h>
25#include <math.h>
26#include <stdint.h>
27
28#include "libavutil/channel_layout.h"
29#include "libavutil/float_dsp.h"
30
31#define BITSTREAM_READER_LE
32#include "avcodec.h"
33#include "codec_internal.h"
34#include "fft.h"
35#include "get_bits.h"
36#include "lsp.h"
37#include "sinewin.h"
38
39#include "twinvq.h"
40#include "metasound_data.h"
41
42static void add_peak(float period, int width, const float *shape,
43                     float ppc_gain, float *speech, int len)
44{
45    int i, j, center;
46    const float *shape_end = shape + len;
47
48    // First peak centered around zero
49    for (i = 0; i < width / 2; i++)
50        speech[i] += ppc_gain * *shape++;
51
52    for (i = 1; i < ROUNDED_DIV(len, width); i++) {
53        center = (int)(i * period + 0.5);
54        for (j = -width / 2; j < (width + 1) / 2; j++)
55            speech[j + center] += ppc_gain * *shape++;
56    }
57
58    // For the last block, be careful not to go beyond the end of the buffer
59    center = (int)(i * period + 0.5);
60    for (j = -width / 2; j < (width + 1) / 2 && shape < shape_end; j++)
61        speech[j + center] += ppc_gain * *shape++;
62}
63
64static void decode_ppc(TwinVQContext *tctx, int period_coef, int g_coef,
65                       const float *shape, float *speech)
66{
67    const TwinVQModeTab *mtab = tctx->mtab;
68    int channels     = tctx->avctx->ch_layout.nb_channels;
69    int isampf       = tctx->avctx->sample_rate / 1000;
70    int ibps         = tctx->avctx->bit_rate / (1000 * channels);
71    int width;
72
73    float ratio = (float)mtab->size / isampf;
74    float min_period, max_period, period_range, period;
75    float some_mult;
76
77    float pgain_base, pgain_step, ppc_gain;
78
79    if (channels == 1) {
80        min_period = log2(ratio * 0.2);
81        max_period = min_period + log2(6);
82    } else {
83        min_period = (int)(ratio * 0.2 * 400     + 0.5) / 400.0;
84        max_period = (int)(ratio * 0.2 * 400 * 6 + 0.5) / 400.0;
85    }
86    period_range = max_period - min_period;
87    period       = min_period + period_coef * period_range /
88                   ((1 << mtab->ppc_period_bit) - 1);
89    if (channels == 1)
90        period = powf(2.0, period);
91    else
92        period = (int)(period * 400 + 0.5) / 400.0;
93
94    switch (isampf) {
95    case  8: some_mult = 2.0; break;
96    case 11: some_mult = 3.0; break;
97    case 16: some_mult = 3.0; break;
98    case 22: some_mult = ibps == 32 ? 2.0 : 4.0; break;
99    case 44: some_mult = 8.0; break;
100    default: some_mult = 4.0;
101    }
102
103    width = (int)(some_mult / (mtab->size / period) * mtab->ppc_shape_len);
104    if (isampf == 22 && ibps == 32)
105        width = (int)((2.0 / period + 1) * width + 0.5);
106
107    pgain_base = channels == 2 ? 25000.0 : 20000.0;
108    pgain_step = pgain_base / ((1 << mtab->pgain_bit) - 1);
109    ppc_gain   = 1.0 / 8192 *
110                 twinvq_mulawinv(pgain_step * g_coef + pgain_step / 2,
111                                 pgain_base, TWINVQ_PGAIN_MU);
112
113    add_peak(period, width, shape, ppc_gain, speech, mtab->ppc_shape_len);
114}
115
116static void dec_bark_env(TwinVQContext *tctx, const uint8_t *in, int use_hist,
117                         int ch, float *out, float gain,
118                         enum TwinVQFrameType ftype)
119{
120    const TwinVQModeTab *mtab = tctx->mtab;
121    int i, j;
122    float *hist     = tctx->bark_hist[ftype][ch];
123    float val       = ((const float []) { 0.4, 0.35, 0.28 })[ftype];
124    int bark_n_coef = mtab->fmode[ftype].bark_n_coef;
125    int fw_cb_len   = mtab->fmode[ftype].bark_env_size / bark_n_coef;
126    int idx         = 0;
127    int channels    = tctx->avctx->ch_layout.nb_channels;
128
129    if (channels == 1)
130        val = 0.5;
131    for (i = 0; i < fw_cb_len; i++)
132        for (j = 0; j < bark_n_coef; j++, idx++) {
133            float tmp2 = mtab->fmode[ftype].bark_cb[fw_cb_len * in[j] + i] *
134                         (1.0 / 2048);
135            float st;
136
137            if (channels == 1)
138                st = use_hist ?
139                    tmp2 + val * hist[idx] + 1.0 : tmp2 + 1.0;
140            else
141                st = use_hist ? (1.0 - val) * tmp2 + val * hist[idx] + 1.0
142                              : tmp2 + 1.0;
143
144            hist[idx] = tmp2;
145            if (st < 0.1)
146                st = 0.1;
147
148            twinvq_memset_float(out, st * gain,
149                                mtab->fmode[ftype].bark_tab[idx]);
150            out += mtab->fmode[ftype].bark_tab[idx];
151        }
152}
153
154static void read_cb_data(TwinVQContext *tctx, GetBitContext *gb,
155                         uint8_t *dst, enum TwinVQFrameType ftype)
156{
157    int i;
158
159    for (i = 0; i < tctx->n_div[ftype]; i++) {
160        int bs_second_part = (i >= tctx->bits_main_spec_change[ftype]);
161
162        *dst++ = get_bits(gb, tctx->bits_main_spec[0][ftype][bs_second_part]);
163        *dst++ = get_bits(gb, tctx->bits_main_spec[1][ftype][bs_second_part]);
164    }
165}
166
167static int metasound_read_bitstream(AVCodecContext *avctx, TwinVQContext *tctx,
168                                    const uint8_t *buf, int buf_size)
169{
170    TwinVQFrameData     *bits;
171    const TwinVQModeTab *mtab = tctx->mtab;
172    int channels              = tctx->avctx->ch_layout.nb_channels;
173    int sub;
174    GetBitContext gb;
175    int i, j, k, ret;
176
177    if ((ret = init_get_bits8(&gb, buf, buf_size)) < 0)
178        return ret;
179
180    for (tctx->cur_frame = 0; tctx->cur_frame < tctx->frames_per_packet;
181         tctx->cur_frame++) {
182        bits = tctx->bits + tctx->cur_frame;
183
184        bits->window_type = get_bits(&gb, TWINVQ_WINDOW_TYPE_BITS);
185
186        if (bits->window_type > 8) {
187            av_log(avctx, AV_LOG_ERROR, "Invalid window type, broken sample?\n");
188            return AVERROR_INVALIDDATA;
189        }
190
191        bits->ftype = ff_twinvq_wtype_to_ftype_table[tctx->bits[tctx->cur_frame].window_type];
192
193        sub = mtab->fmode[bits->ftype].sub;
194
195        if (bits->ftype != TWINVQ_FT_SHORT && !tctx->is_6kbps)
196            get_bits(&gb, 2);
197
198        read_cb_data(tctx, &gb, bits->main_coeffs, bits->ftype);
199
200        for (i = 0; i < channels; i++)
201            for (j = 0; j < sub; j++)
202                for (k = 0; k < mtab->fmode[bits->ftype].bark_n_coef; k++)
203                    bits->bark1[i][j][k] =
204                        get_bits(&gb, mtab->fmode[bits->ftype].bark_n_bit);
205
206        for (i = 0; i < channels; i++)
207            for (j = 0; j < sub; j++)
208                bits->bark_use_hist[i][j] = get_bits1(&gb);
209
210        if (bits->ftype == TWINVQ_FT_LONG) {
211            for (i = 0; i < channels; i++)
212                bits->gain_bits[i] = get_bits(&gb, TWINVQ_GAIN_BITS);
213        } else {
214            for (i = 0; i < channels; i++) {
215                bits->gain_bits[i] = get_bits(&gb, TWINVQ_GAIN_BITS);
216                for (j = 0; j < sub; j++)
217                    bits->sub_gain_bits[i * sub + j] =
218                        get_bits(&gb, TWINVQ_SUB_GAIN_BITS);
219            }
220        }
221
222        for (i = 0; i < channels; i++) {
223            bits->lpc_hist_idx[i] = get_bits(&gb, mtab->lsp_bit0);
224            bits->lpc_idx1[i]     = get_bits(&gb, mtab->lsp_bit1);
225
226            for (j = 0; j < mtab->lsp_split; j++)
227                bits->lpc_idx2[i][j] = get_bits(&gb, mtab->lsp_bit2);
228        }
229
230        if (bits->ftype == TWINVQ_FT_LONG) {
231            read_cb_data(tctx, &gb, bits->ppc_coeffs, 3);
232            for (i = 0; i < channels; i++) {
233                bits->p_coef[i] = get_bits(&gb, mtab->ppc_period_bit);
234                bits->g_coef[i] = get_bits(&gb, mtab->pgain_bit);
235            }
236        }
237
238        // subframes are aligned to nibbles
239        if (get_bits_count(&gb) & 3)
240            skip_bits(&gb, 4 - (get_bits_count(&gb) & 3));
241    }
242
243    return (get_bits_count(&gb) + 7) / 8;
244}
245
246typedef struct MetasoundProps {
247    uint32_t tag;
248    int      bit_rate;
249    int      channels;
250    int      sample_rate;
251} MetasoundProps;
252
253static const MetasoundProps codec_props[] = {
254    { MKTAG('V','X','0','3'),  6, 1,  8000 },
255    { MKTAG('V','X','0','4'), 12, 2,  8000 },
256
257    { MKTAG('V','O','X','i'),  8, 1,  8000 },
258    { MKTAG('V','O','X','j'), 10, 1, 11025 },
259    { MKTAG('V','O','X','k'), 16, 1, 16000 },
260    { MKTAG('V','O','X','L'), 24, 1, 22050 },
261    { MKTAG('V','O','X','q'), 32, 1, 44100 },
262    { MKTAG('V','O','X','r'), 40, 1, 44100 },
263    { MKTAG('V','O','X','s'), 48, 1, 44100 },
264    { MKTAG('V','O','X','t'), 16, 2,  8000 },
265    { MKTAG('V','O','X','u'), 20, 2, 11025 },
266    { MKTAG('V','O','X','v'), 32, 2, 16000 },
267    { MKTAG('V','O','X','w'), 48, 2, 22050 },
268    { MKTAG('V','O','X','x'), 64, 2, 44100 },
269    { MKTAG('V','O','X','y'), 80, 2, 44100 },
270    { MKTAG('V','O','X','z'), 96, 2, 44100 },
271
272    { 0, 0, 0, 0 }
273};
274
275static av_cold int metasound_decode_init(AVCodecContext *avctx)
276{
277    int isampf, ibps;
278    TwinVQContext *tctx = avctx->priv_data;
279    uint32_t tag;
280    const MetasoundProps *props = codec_props;
281    int channels;
282
283    if (!avctx->extradata || avctx->extradata_size < 16) {
284        av_log(avctx, AV_LOG_ERROR, "Missing or incomplete extradata\n");
285        return AVERROR_INVALIDDATA;
286    }
287
288    tag = AV_RL32(avctx->extradata + 12);
289
290    for (;;) {
291        if (!props->tag) {
292            av_log(avctx, AV_LOG_ERROR, "Could not find tag %08"PRIX32"\n", tag);
293            return AVERROR_INVALIDDATA;
294        }
295        if (props->tag == tag) {
296            avctx->sample_rate = props->sample_rate;
297            channels           = props->channels;
298            avctx->bit_rate    = props->bit_rate * 1000;
299            isampf             = avctx->sample_rate / 1000;
300            break;
301        }
302        props++;
303    }
304
305    if (channels <= 0 || channels > TWINVQ_CHANNELS_MAX) {
306        av_log(avctx, AV_LOG_ERROR, "Unsupported number of channels: %i\n",
307               channels);
308        return AVERROR_INVALIDDATA;
309    }
310    av_channel_layout_uninit(&avctx->ch_layout);
311    av_channel_layout_default(&avctx->ch_layout, channels);
312
313    ibps = avctx->bit_rate / (1000 * channels);
314
315    switch ((channels << 16) + (isampf << 8) + ibps) {
316    case (1 << 16) + ( 8 << 8) +  6:
317        tctx->mtab = &ff_metasound_mode0806;
318        break;
319    case (2 << 16) + ( 8 << 8) +  6:
320        tctx->mtab = &ff_metasound_mode0806s;
321        break;
322    case (1 << 16) + ( 8 << 8) +  8:
323        tctx->mtab = &ff_metasound_mode0808;
324        break;
325    case (2 << 16) + ( 8 << 8) +  8:
326        tctx->mtab = &ff_metasound_mode0808s;
327        break;
328    case (1 << 16) + (11 << 8) + 10:
329        tctx->mtab = &ff_metasound_mode1110;
330        break;
331    case (2 << 16) + (11 << 8) + 10:
332        tctx->mtab = &ff_metasound_mode1110s;
333        break;
334    case (1 << 16) + (16 << 8) + 16:
335        tctx->mtab = &ff_metasound_mode1616;
336        break;
337    case (2 << 16) + (16 << 8) + 16:
338        tctx->mtab = &ff_metasound_mode1616s;
339        break;
340    case (1 << 16) + (22 << 8) + 24:
341        tctx->mtab = &ff_metasound_mode2224;
342        break;
343    case (2 << 16) + (22 << 8) + 24:
344        tctx->mtab = &ff_metasound_mode2224s;
345        break;
346    case (1 << 16) + (44 << 8) + 32:
347    case (2 << 16) + (44 << 8) + 32:
348        tctx->mtab = &ff_metasound_mode4432;
349        break;
350    case (1 << 16) + (44 << 8) + 40:
351    case (2 << 16) + (44 << 8) + 40:
352        tctx->mtab = &ff_metasound_mode4440;
353        break;
354    case (1 << 16) + (44 << 8) + 48:
355    case (2 << 16) + (44 << 8) + 48:
356        tctx->mtab = &ff_metasound_mode4448;
357        break;
358    default:
359        av_log(avctx, AV_LOG_ERROR,
360               "This version does not support %d kHz - %d kbit/s/ch mode.\n",
361               isampf, ibps);
362        return AVERROR(ENOSYS);
363    }
364
365    tctx->codec          = TWINVQ_CODEC_METASOUND;
366    tctx->read_bitstream = metasound_read_bitstream;
367    tctx->dec_bark_env   = dec_bark_env;
368    tctx->decode_ppc     = decode_ppc;
369    tctx->frame_size     = avctx->bit_rate * tctx->mtab->size
370                                           / avctx->sample_rate;
371    tctx->is_6kbps       = ibps == 6;
372
373    return ff_twinvq_decode_init(avctx);
374}
375
376const FFCodec ff_metasound_decoder = {
377    .p.name         = "metasound",
378    .p.long_name    = NULL_IF_CONFIG_SMALL("Voxware MetaSound"),
379    .p.type         = AVMEDIA_TYPE_AUDIO,
380    .p.id           = AV_CODEC_ID_METASOUND,
381    .priv_data_size = sizeof(TwinVQContext),
382    .init           = metasound_decode_init,
383    .close          = ff_twinvq_decode_close,
384    FF_CODEC_DECODE_CB(ff_twinvq_decode_frame),
385    .p.capabilities = AV_CODEC_CAP_DR1 | AV_CODEC_CAP_CHANNEL_CONF,
386    .p.sample_fmts  = (const enum AVSampleFormat[]) { AV_SAMPLE_FMT_FLTP,
387                                                      AV_SAMPLE_FMT_NONE },
388    .caps_internal  = FF_CODEC_CAP_INIT_THREADSAFE | FF_CODEC_CAP_INIT_CLEANUP,
389};
390