1/*
2 * Musepack SV8 decoder
3 * Copyright (c) 2007 Konstantin Shishkov
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/**
23 * @file
24 * MPEG Audio Layer 1/2 -like codec with frames of 1152 samples
25 * divided into 32 subbands.
26 */
27
28#include "libavutil/channel_layout.h"
29#include "libavutil/lfg.h"
30#include "avcodec.h"
31#include "get_bits.h"
32#include "internal.h"
33#include "mpegaudiodsp.h"
34
35#include "mpc.h"
36#include "mpc8data.h"
37#include "mpc8huff.h"
38
39static VLC band_vlc, scfi_vlc[2], dscf_vlc[2], res_vlc[2];
40static VLC q1_vlc, q2_vlc[2], q3_vlc[2], quant_vlc[4][2], q9up_vlc;
41
42static const int q3_offsets[2] = { MPC8_Q3_OFFSET, MPC8_Q4_OFFSET };
43static const int quant_offsets[6] = { MPC8_Q5_OFFSET, MPC8_Q6_OFFSET, MPC8_Q7_OFFSET, MPC8_Q8_OFFSET };
44
45static inline int mpc8_dec_base(GetBitContext *gb, int k, int n)
46{
47    int len = mpc8_cnk_len[k-1][n-1] - 1;
48    int code = len ? get_bits_long(gb, len) : 0;
49
50    if (code >= mpc8_cnk_lost[k-1][n-1])
51        code = ((code << 1) | get_bits1(gb)) - mpc8_cnk_lost[k-1][n-1];
52
53    return code;
54}
55
56static inline int mpc8_dec_enum(GetBitContext *gb, int k, int n)
57{
58    int bits = 0;
59    const uint32_t * C = mpc8_cnk[k-1];
60    int code = mpc8_dec_base(gb, k, n);
61
62    do {
63        n--;
64        if (code >= C[n]) {
65            bits |= 1 << n;
66            code -= C[n];
67            C -= 32;
68            k--;
69        }
70    } while(k > 0);
71
72    return bits;
73}
74
75static inline int mpc8_get_mod_golomb(GetBitContext *gb, int m)
76{
77    if(mpc8_cnk_len[0][m] < 1) return 0;
78    return mpc8_dec_base(gb, 1, m+1);
79}
80
81static int mpc8_get_mask(GetBitContext *gb, int size, int t)
82{
83    int mask = 0;
84
85    if(t && t != size)
86         mask = mpc8_dec_enum(gb, FFMIN(t, size - t), size);
87    if((t << 1) > size) mask = ~mask;
88
89    return mask;
90}
91
92static const uint16_t vlc_offsets[13] = {
93    0, 640, 1184, 1748, 2298, 2426, 2554, 3066, 3578, 4106, 4618, 5196, 5708
94};
95
96static av_cold int mpc8_decode_init(AVCodecContext * avctx)
97{
98    int i;
99    MPCContext *c = avctx->priv_data;
100    GetBitContext gb;
101    static int vlc_initialized = 0;
102    int channels;
103
104    static VLC_TYPE band_table[542][2];
105    static VLC_TYPE q1_table[520][2];
106    static VLC_TYPE q9up_table[524][2];
107    static VLC_TYPE scfi0_table[1 << MPC8_SCFI0_BITS][2];
108    static VLC_TYPE scfi1_table[1 << MPC8_SCFI1_BITS][2];
109    static VLC_TYPE dscf0_table[560][2];
110    static VLC_TYPE dscf1_table[598][2];
111    static VLC_TYPE q3_0_table[512][2];
112    static VLC_TYPE q3_1_table[516][2];
113    static VLC_TYPE codes_table[5708][2];
114
115    if(avctx->extradata_size < 2){
116        av_log(avctx, AV_LOG_ERROR, "Too small extradata size (%i)!\n", avctx->extradata_size);
117        return -1;
118    }
119    memset(c->oldDSCF, 0, sizeof(c->oldDSCF));
120    av_lfg_init(&c->rnd, 0xDEADBEEF);
121    ff_mpadsp_init(&c->mpadsp);
122
123    ff_mpc_init();
124
125    init_get_bits(&gb, avctx->extradata, 16);
126
127    skip_bits(&gb, 3);//sample rate
128    c->maxbands = get_bits(&gb, 5) + 1;
129    if (c->maxbands >= BANDS) {
130        av_log(avctx,AV_LOG_ERROR, "maxbands %d too high\n", c->maxbands);
131        return AVERROR_INVALIDDATA;
132    }
133    channels = get_bits(&gb, 4) + 1;
134    if (channels > 2) {
135        avpriv_request_sample(avctx, "Multichannel MPC SV8");
136        return AVERROR_PATCHWELCOME;
137    }
138    c->MSS = get_bits1(&gb);
139    c->frames = 1 << (get_bits(&gb, 3) * 2);
140
141    avctx->sample_fmt = AV_SAMPLE_FMT_S16P;
142    avctx->channel_layout = (channels==2) ? AV_CH_LAYOUT_STEREO : AV_CH_LAYOUT_MONO;
143    avctx->channels = channels;
144
145    if(vlc_initialized) return 0;
146    av_log(avctx, AV_LOG_DEBUG, "Initing VLC\n");
147
148    band_vlc.table = band_table;
149    band_vlc.table_allocated = 542;
150    init_vlc(&band_vlc, MPC8_BANDS_BITS, MPC8_BANDS_SIZE,
151             mpc8_bands_bits,  1, 1,
152             mpc8_bands_codes, 1, 1, INIT_VLC_USE_NEW_STATIC);
153
154    q1_vlc.table = q1_table;
155    q1_vlc.table_allocated = 520;
156    init_vlc(&q1_vlc, MPC8_Q1_BITS, MPC8_Q1_SIZE,
157             mpc8_q1_bits,  1, 1,
158             mpc8_q1_codes, 1, 1, INIT_VLC_USE_NEW_STATIC);
159    q9up_vlc.table = q9up_table;
160    q9up_vlc.table_allocated = 524;
161    init_vlc(&q9up_vlc, MPC8_Q9UP_BITS, MPC8_Q9UP_SIZE,
162             mpc8_q9up_bits,  1, 1,
163             mpc8_q9up_codes, 1, 1, INIT_VLC_USE_NEW_STATIC);
164
165    scfi_vlc[0].table = scfi0_table;
166    scfi_vlc[0].table_allocated = 1 << MPC8_SCFI0_BITS;
167    init_vlc(&scfi_vlc[0], MPC8_SCFI0_BITS, MPC8_SCFI0_SIZE,
168             mpc8_scfi0_bits,  1, 1,
169             mpc8_scfi0_codes, 1, 1, INIT_VLC_USE_NEW_STATIC);
170    scfi_vlc[1].table = scfi1_table;
171    scfi_vlc[1].table_allocated = 1 << MPC8_SCFI1_BITS;
172    init_vlc(&scfi_vlc[1], MPC8_SCFI1_BITS, MPC8_SCFI1_SIZE,
173             mpc8_scfi1_bits,  1, 1,
174             mpc8_scfi1_codes, 1, 1, INIT_VLC_USE_NEW_STATIC);
175
176    dscf_vlc[0].table = dscf0_table;
177    dscf_vlc[0].table_allocated = 560;
178    init_vlc(&dscf_vlc[0], MPC8_DSCF0_BITS, MPC8_DSCF0_SIZE,
179             mpc8_dscf0_bits,  1, 1,
180             mpc8_dscf0_codes, 1, 1, INIT_VLC_USE_NEW_STATIC);
181    dscf_vlc[1].table = dscf1_table;
182    dscf_vlc[1].table_allocated = 598;
183    init_vlc(&dscf_vlc[1], MPC8_DSCF1_BITS, MPC8_DSCF1_SIZE,
184             mpc8_dscf1_bits,  1, 1,
185             mpc8_dscf1_codes, 1, 1, INIT_VLC_USE_NEW_STATIC);
186
187    q3_vlc[0].table = q3_0_table;
188    q3_vlc[0].table_allocated = 512;
189    ff_init_vlc_sparse(&q3_vlc[0], MPC8_Q3_BITS, MPC8_Q3_SIZE,
190             mpc8_q3_bits,  1, 1,
191             mpc8_q3_codes, 1, 1,
192             mpc8_q3_syms,  1, 1, INIT_VLC_USE_NEW_STATIC);
193    q3_vlc[1].table = q3_1_table;
194    q3_vlc[1].table_allocated = 516;
195    ff_init_vlc_sparse(&q3_vlc[1], MPC8_Q4_BITS, MPC8_Q4_SIZE,
196             mpc8_q4_bits,  1, 1,
197             mpc8_q4_codes, 1, 1,
198             mpc8_q4_syms,  1, 1, INIT_VLC_USE_NEW_STATIC);
199
200    for(i = 0; i < 2; i++){
201        res_vlc[i].table = &codes_table[vlc_offsets[0+i]];
202        res_vlc[i].table_allocated = vlc_offsets[1+i] - vlc_offsets[0+i];
203        init_vlc(&res_vlc[i], MPC8_RES_BITS, MPC8_RES_SIZE,
204                 &mpc8_res_bits[i],  1, 1,
205                 &mpc8_res_codes[i], 1, 1, INIT_VLC_USE_NEW_STATIC);
206
207        q2_vlc[i].table = &codes_table[vlc_offsets[2+i]];
208        q2_vlc[i].table_allocated = vlc_offsets[3+i] - vlc_offsets[2+i];
209        init_vlc(&q2_vlc[i], MPC8_Q2_BITS, MPC8_Q2_SIZE,
210                 &mpc8_q2_bits[i],  1, 1,
211                 &mpc8_q2_codes[i], 1, 1, INIT_VLC_USE_NEW_STATIC);
212
213        quant_vlc[0][i].table = &codes_table[vlc_offsets[4+i]];
214        quant_vlc[0][i].table_allocated = vlc_offsets[5+i] - vlc_offsets[4+i];
215        init_vlc(&quant_vlc[0][i], MPC8_Q5_BITS, MPC8_Q5_SIZE,
216                 &mpc8_q5_bits[i],  1, 1,
217                 &mpc8_q5_codes[i], 1, 1, INIT_VLC_USE_NEW_STATIC);
218        quant_vlc[1][i].table = &codes_table[vlc_offsets[6+i]];
219        quant_vlc[1][i].table_allocated = vlc_offsets[7+i] - vlc_offsets[6+i];
220        init_vlc(&quant_vlc[1][i], MPC8_Q6_BITS, MPC8_Q6_SIZE,
221                 &mpc8_q6_bits[i],  1, 1,
222                 &mpc8_q6_codes[i], 1, 1, INIT_VLC_USE_NEW_STATIC);
223        quant_vlc[2][i].table = &codes_table[vlc_offsets[8+i]];
224        quant_vlc[2][i].table_allocated = vlc_offsets[9+i] - vlc_offsets[8+i];
225        init_vlc(&quant_vlc[2][i], MPC8_Q7_BITS, MPC8_Q7_SIZE,
226                 &mpc8_q7_bits[i],  1, 1,
227                 &mpc8_q7_codes[i], 1, 1, INIT_VLC_USE_NEW_STATIC);
228        quant_vlc[3][i].table = &codes_table[vlc_offsets[10+i]];
229        quant_vlc[3][i].table_allocated = vlc_offsets[11+i] - vlc_offsets[10+i];
230        init_vlc(&quant_vlc[3][i], MPC8_Q8_BITS, MPC8_Q8_SIZE,
231                 &mpc8_q8_bits[i],  1, 1,
232                 &mpc8_q8_codes[i], 1, 1, INIT_VLC_USE_NEW_STATIC);
233    }
234    vlc_initialized = 1;
235
236    return 0;
237}
238
239static int mpc8_decode_frame(AVCodecContext * avctx, void *data,
240                             int *got_frame_ptr, AVPacket *avpkt)
241{
242    AVFrame *frame     = data;
243    const uint8_t *buf = avpkt->data;
244    int buf_size = avpkt->size;
245    MPCContext *c = avctx->priv_data;
246    GetBitContext gb2, *gb = &gb2;
247    int i, j, k, ch, cnt, res, t;
248    Band *bands = c->bands;
249    int off;
250    int maxband, keyframe;
251    int last[2];
252
253    /* get output buffer */
254    frame->nb_samples = MPC_FRAME_SIZE;
255    if ((res = ff_get_buffer(avctx, frame, 0)) < 0)
256        return res;
257
258    keyframe = c->cur_frame == 0;
259
260    if(keyframe){
261        memset(c->Q, 0, sizeof(c->Q));
262        c->last_bits_used = 0;
263    }
264    init_get_bits(gb, buf, buf_size * 8);
265    skip_bits(gb, c->last_bits_used & 7);
266
267    if(keyframe)
268        maxband = mpc8_get_mod_golomb(gb, c->maxbands + 1);
269    else{
270        maxband = c->last_max_band + get_vlc2(gb, band_vlc.table, MPC8_BANDS_BITS, 2);
271        if(maxband > 32) maxband -= 33;
272    }
273
274    if(maxband > c->maxbands + 1) {
275        av_log(avctx, AV_LOG_ERROR, "maxband %d too large\n",maxband);
276        return AVERROR_INVALIDDATA;
277    }
278    c->last_max_band = maxband;
279
280    /* read subband indexes */
281    if(maxband){
282        last[0] = last[1] = 0;
283        for(i = maxband - 1; i >= 0; i--){
284            for(ch = 0; ch < 2; ch++){
285                last[ch] = get_vlc2(gb, res_vlc[last[ch] > 2].table, MPC8_RES_BITS, 2) + last[ch];
286                if(last[ch] > 15) last[ch] -= 17;
287                bands[i].res[ch] = last[ch];
288            }
289        }
290        if(c->MSS){
291            int mask;
292
293            cnt = 0;
294            for(i = 0; i < maxband; i++)
295                if(bands[i].res[0] || bands[i].res[1])
296                    cnt++;
297            t = mpc8_get_mod_golomb(gb, cnt);
298            mask = mpc8_get_mask(gb, cnt, t);
299            for(i = maxband - 1; i >= 0; i--)
300                if(bands[i].res[0] || bands[i].res[1]){
301                    bands[i].msf = mask & 1;
302                    mask >>= 1;
303                }
304        }
305    }
306    for(i = maxband; i < c->maxbands; i++)
307        bands[i].res[0] = bands[i].res[1] = 0;
308
309    if(keyframe){
310        for(i = 0; i < 32; i++)
311            c->oldDSCF[0][i] = c->oldDSCF[1][i] = 1;
312    }
313
314    for(i = 0; i < maxband; i++){
315        if(bands[i].res[0] || bands[i].res[1]){
316            cnt = !!bands[i].res[0] + !!bands[i].res[1] - 1;
317            if(cnt >= 0){
318                t = get_vlc2(gb, scfi_vlc[cnt].table, scfi_vlc[cnt].bits, 1);
319                if(bands[i].res[0]) bands[i].scfi[0] = t >> (2 * cnt);
320                if(bands[i].res[1]) bands[i].scfi[1] = t & 3;
321            }
322        }
323    }
324
325    for(i = 0; i < maxband; i++){
326        for(ch = 0; ch < 2; ch++){
327            if(!bands[i].res[ch]) continue;
328
329            if(c->oldDSCF[ch][i]){
330                bands[i].scf_idx[ch][0] = get_bits(gb, 7) - 6;
331                c->oldDSCF[ch][i] = 0;
332            }else{
333                t = get_vlc2(gb, dscf_vlc[1].table, MPC8_DSCF1_BITS, 2);
334                if(t == 64)
335                    t += get_bits(gb, 6);
336                bands[i].scf_idx[ch][0] = ((bands[i].scf_idx[ch][2] + t - 25) & 0x7F) - 6;
337            }
338            for(j = 0; j < 2; j++){
339                if((bands[i].scfi[ch] << j) & 2)
340                    bands[i].scf_idx[ch][j + 1] = bands[i].scf_idx[ch][j];
341                else{
342                    t = get_vlc2(gb, dscf_vlc[0].table, MPC8_DSCF0_BITS, 2);
343                    if(t == 31)
344                        t = 64 + get_bits(gb, 6);
345                    bands[i].scf_idx[ch][j + 1] = ((bands[i].scf_idx[ch][j] + t - 25) & 0x7F) - 6;
346                }
347            }
348        }
349    }
350
351    for(i = 0, off = 0; i < maxband; i++, off += SAMPLES_PER_BAND){
352        for(ch = 0; ch < 2; ch++){
353            res = bands[i].res[ch];
354            switch(res){
355            case -1:
356                for(j = 0; j < SAMPLES_PER_BAND; j++)
357                    c->Q[ch][off + j] = (av_lfg_get(&c->rnd) & 0x3FC) - 510;
358                break;
359            case 0:
360                break;
361            case 1:
362                for(j = 0; j < SAMPLES_PER_BAND; j += SAMPLES_PER_BAND / 2){
363                    cnt = get_vlc2(gb, q1_vlc.table, MPC8_Q1_BITS, 2);
364                    t = mpc8_get_mask(gb, 18, cnt);
365                    for(k = 0; k < SAMPLES_PER_BAND / 2; k++, t <<= 1)
366                        c->Q[ch][off + j + k] = (t & 0x20000) ? (get_bits1(gb) << 1) - 1 : 0;
367                }
368                break;
369            case 2:
370                cnt = 6;//2*mpc8_thres[res]
371                for(j = 0; j < SAMPLES_PER_BAND; j += 3){
372                    t = get_vlc2(gb, q2_vlc[cnt > 3].table, MPC8_Q2_BITS, 2);
373                    c->Q[ch][off + j + 0] = mpc8_idx50[t];
374                    c->Q[ch][off + j + 1] = mpc8_idx51[t];
375                    c->Q[ch][off + j + 2] = mpc8_idx52[t];
376                    cnt = (cnt >> 1) + mpc8_huffq2[t];
377                }
378                break;
379            case 3:
380            case 4:
381                for(j = 0; j < SAMPLES_PER_BAND; j += 2){
382                    t = get_vlc2(gb, q3_vlc[res - 3].table, MPC8_Q3_BITS, 2) + q3_offsets[res - 3];
383                    c->Q[ch][off + j + 1] = t >> 4;
384                    c->Q[ch][off + j + 0] = (t & 8) ? (t & 0xF) - 16 : (t & 0xF);
385                }
386                break;
387            case 5:
388            case 6:
389            case 7:
390            case 8:
391                cnt = 2 * mpc8_thres[res];
392                for(j = 0; j < SAMPLES_PER_BAND; j++){
393                    t = get_vlc2(gb, quant_vlc[res - 5][cnt > mpc8_thres[res]].table, quant_vlc[res - 5][cnt > mpc8_thres[res]].bits, 2) + quant_offsets[res - 5];
394                    c->Q[ch][off + j] = t;
395                    cnt = (cnt >> 1) + FFABS(c->Q[ch][off + j]);
396                }
397                break;
398            default:
399                for(j = 0; j < SAMPLES_PER_BAND; j++){
400                    c->Q[ch][off + j] = get_vlc2(gb, q9up_vlc.table, MPC8_Q9UP_BITS, 2);
401                    if(res != 9){
402                        c->Q[ch][off + j] <<= res - 9;
403                        c->Q[ch][off + j] |= get_bits(gb, res - 9);
404                    }
405                    c->Q[ch][off + j] -= (1 << (res - 2)) - 1;
406                }
407            }
408        }
409    }
410
411    ff_mpc_dequantize_and_synth(c, maxband - 1,
412                                (int16_t **)frame->extended_data,
413                                avctx->channels);
414
415    c->cur_frame++;
416
417    c->last_bits_used = get_bits_count(gb);
418    if(get_bits_left(gb) < 8) // we have only padding left
419        c->last_bits_used = buf_size << 3;
420    if(c->cur_frame >= c->frames)
421        c->cur_frame = 0;
422
423    *got_frame_ptr = 1;
424
425    return c->cur_frame ? c->last_bits_used >> 3 : buf_size;
426}
427
428static av_cold void mpc8_decode_flush(AVCodecContext *avctx)
429{
430    MPCContext *c = avctx->priv_data;
431    c->cur_frame = 0;
432}
433
434AVCodec ff_mpc8_decoder = {
435    .name           = "mpc8",
436    .long_name      = NULL_IF_CONFIG_SMALL("Musepack SV8"),
437    .type           = AVMEDIA_TYPE_AUDIO,
438    .id             = AV_CODEC_ID_MUSEPACK8,
439    .priv_data_size = sizeof(MPCContext),
440    .init           = mpc8_decode_init,
441    .decode         = mpc8_decode_frame,
442    .flush          = mpc8_decode_flush,
443    .capabilities   = CODEC_CAP_DR1,
444    .sample_fmts    = (const enum AVSampleFormat[]) { AV_SAMPLE_FMT_S16P,
445                                                      AV_SAMPLE_FMT_NONE },
446};
447