mpc8.c
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1 /*
2  * Musepack SV8 decoder
3  * Copyright (c) 2007 Konstantin Shishkov
4  *
5  * This file is part of Libav.
6  *
7  * Libav 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  * Libav 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 Libav; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
28 #include "libavutil/lfg.h"
29 #include "avcodec.h"
30 #include "get_bits.h"
31 #include "dsputil.h"
32 #include "mpegaudiodsp.h"
33 #include "libavutil/audioconvert.h"
34 
35 #include "mpc.h"
36 #include "mpc8data.h"
37 #include "mpc8huff.h"
38 
39 static VLC band_vlc, scfi_vlc[2], dscf_vlc[2], res_vlc[2];
40 static VLC q1_vlc, q2_vlc[2], q3_vlc[2], quant_vlc[4][2], q9up_vlc;
41 
42 static const int q3_offsets[2] = { MPC8_Q3_OFFSET, MPC8_Q4_OFFSET };
44 
45 static 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 
56 static 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 
75 static 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 
81 static 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 
92 static const uint16_t vlc_offsets[13] = {
93  0, 640, 1184, 1748, 2298, 2426, 2554, 3066, 3578, 4106, 4618, 5196, 5708
94 };
95 
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  dsputil_init(&c->dsp, avctx);
122  ff_mpadsp_init(&c->mpadsp);
123 
124  ff_mpc_init();
125 
126  init_get_bits(&gb, avctx->extradata, 16);
127 
128  skip_bits(&gb, 3);//sample rate
129  c->maxbands = get_bits(&gb, 5) + 1;
130  channels = get_bits(&gb, 4) + 1;
131  if (channels > 2) {
132  av_log_missing_feature(avctx, "Multichannel MPC SV8", 1);
133  return -1;
134  }
135  c->MSS = get_bits1(&gb);
136  c->frames = 1 << (get_bits(&gb, 3) * 2);
137 
138  avctx->sample_fmt = AV_SAMPLE_FMT_S16;
140 
141  if(vlc_initialized) return 0;
142  av_log(avctx, AV_LOG_DEBUG, "Initing VLC\n");
143 
144  band_vlc.table = band_table;
145  band_vlc.table_allocated = 542;
147  mpc8_bands_bits, 1, 1,
149 
150  q1_vlc.table = q1_table;
151  q1_vlc.table_allocated = 520;
153  mpc8_q1_bits, 1, 1,
155  q9up_vlc.table = q9up_table;
156  q9up_vlc.table_allocated = 524;
158  mpc8_q9up_bits, 1, 1,
160 
161  scfi_vlc[0].table = scfi0_table;
162  scfi_vlc[0].table_allocated = 1 << MPC8_SCFI0_BITS;
164  mpc8_scfi0_bits, 1, 1,
166  scfi_vlc[1].table = scfi1_table;
167  scfi_vlc[1].table_allocated = 1 << MPC8_SCFI1_BITS;
169  mpc8_scfi1_bits, 1, 1,
171 
172  dscf_vlc[0].table = dscf0_table;
173  dscf_vlc[0].table_allocated = 560;
175  mpc8_dscf0_bits, 1, 1,
177  dscf_vlc[1].table = dscf1_table;
178  dscf_vlc[1].table_allocated = 598;
180  mpc8_dscf1_bits, 1, 1,
182 
183  q3_vlc[0].table = q3_0_table;
184  q3_vlc[0].table_allocated = 512;
186  mpc8_q3_bits, 1, 1,
187  mpc8_q3_codes, 1, 1,
189  q3_vlc[1].table = q3_1_table;
190  q3_vlc[1].table_allocated = 516;
192  mpc8_q4_bits, 1, 1,
193  mpc8_q4_codes, 1, 1,
195 
196  for(i = 0; i < 2; i++){
197  res_vlc[i].table = &codes_table[vlc_offsets[0+i]];
198  res_vlc[i].table_allocated = vlc_offsets[1+i] - vlc_offsets[0+i];
199  init_vlc(&res_vlc[i], MPC8_RES_BITS, MPC8_RES_SIZE,
200  &mpc8_res_bits[i], 1, 1,
202 
203  q2_vlc[i].table = &codes_table[vlc_offsets[2+i]];
204  q2_vlc[i].table_allocated = vlc_offsets[3+i] - vlc_offsets[2+i];
205  init_vlc(&q2_vlc[i], MPC8_Q2_BITS, MPC8_Q2_SIZE,
206  &mpc8_q2_bits[i], 1, 1,
208 
209  quant_vlc[0][i].table = &codes_table[vlc_offsets[4+i]];
210  quant_vlc[0][i].table_allocated = vlc_offsets[5+i] - vlc_offsets[4+i];
211  init_vlc(&quant_vlc[0][i], MPC8_Q5_BITS, MPC8_Q5_SIZE,
212  &mpc8_q5_bits[i], 1, 1,
214  quant_vlc[1][i].table = &codes_table[vlc_offsets[6+i]];
215  quant_vlc[1][i].table_allocated = vlc_offsets[7+i] - vlc_offsets[6+i];
216  init_vlc(&quant_vlc[1][i], MPC8_Q6_BITS, MPC8_Q6_SIZE,
217  &mpc8_q6_bits[i], 1, 1,
219  quant_vlc[2][i].table = &codes_table[vlc_offsets[8+i]];
220  quant_vlc[2][i].table_allocated = vlc_offsets[9+i] - vlc_offsets[8+i];
221  init_vlc(&quant_vlc[2][i], MPC8_Q7_BITS, MPC8_Q7_SIZE,
222  &mpc8_q7_bits[i], 1, 1,
224  quant_vlc[3][i].table = &codes_table[vlc_offsets[10+i]];
225  quant_vlc[3][i].table_allocated = vlc_offsets[11+i] - vlc_offsets[10+i];
226  init_vlc(&quant_vlc[3][i], MPC8_Q8_BITS, MPC8_Q8_SIZE,
227  &mpc8_q8_bits[i], 1, 1,
229  }
230  vlc_initialized = 1;
231 
233  avctx->coded_frame = &c->frame;
234 
235  return 0;
236 }
237 
238 static int mpc8_decode_frame(AVCodecContext * avctx, void *data,
239  int *got_frame_ptr, AVPacket *avpkt)
240 {
241  const uint8_t *buf = avpkt->data;
242  int buf_size = avpkt->size;
243  MPCContext *c = avctx->priv_data;
244  GetBitContext gb2, *gb = &gb2;
245  int i, j, k, ch, cnt, res, t;
246  Band *bands = c->bands;
247  int off;
248  int maxband, keyframe;
249  int last[2];
250 
251  /* get output buffer */
253  if ((res = avctx->get_buffer(avctx, &c->frame)) < 0) {
254  av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
255  return res;
256  }
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  if(maxband > c->maxbands)
274  return AVERROR_INVALIDDATA;
275  c->last_max_band = maxband;
276 
277  /* read subband indexes */
278  if(maxband){
279  last[0] = last[1] = 0;
280  for(i = maxband - 1; i >= 0; i--){
281  for(ch = 0; ch < 2; ch++){
282  last[ch] = get_vlc2(gb, res_vlc[last[ch] > 2].table, MPC8_RES_BITS, 2) + last[ch];
283  if(last[ch] > 15) last[ch] -= 17;
284  bands[i].res[ch] = last[ch];
285  }
286  }
287  if(c->MSS){
288  int mask;
289 
290  cnt = 0;
291  for(i = 0; i < maxband; i++)
292  if(bands[i].res[0] || bands[i].res[1])
293  cnt++;
294  t = mpc8_get_mod_golomb(gb, cnt);
295  mask = mpc8_get_mask(gb, cnt, t);
296  for(i = maxband - 1; i >= 0; i--)
297  if(bands[i].res[0] || bands[i].res[1]){
298  bands[i].msf = mask & 1;
299  mask >>= 1;
300  }
301  }
302  }
303  for(i = maxband; i < c->maxbands; i++)
304  bands[i].res[0] = bands[i].res[1] = 0;
305 
306  if(keyframe){
307  for(i = 0; i < 32; i++)
308  c->oldDSCF[0][i] = c->oldDSCF[1][i] = 1;
309  }
310 
311  for(i = 0; i < maxband; i++){
312  if(bands[i].res[0] || bands[i].res[1]){
313  cnt = !!bands[i].res[0] + !!bands[i].res[1] - 1;
314  if(cnt >= 0){
315  t = get_vlc2(gb, scfi_vlc[cnt].table, scfi_vlc[cnt].bits, 1);
316  if(bands[i].res[0]) bands[i].scfi[0] = t >> (2 * cnt);
317  if(bands[i].res[1]) bands[i].scfi[1] = t & 3;
318  }
319  }
320  }
321 
322  for(i = 0; i < maxband; i++){
323  for(ch = 0; ch < 2; ch++){
324  if(!bands[i].res[ch]) continue;
325 
326  if(c->oldDSCF[ch][i]){
327  bands[i].scf_idx[ch][0] = get_bits(gb, 7) - 6;
328  c->oldDSCF[ch][i] = 0;
329  }else{
330  t = get_vlc2(gb, dscf_vlc[1].table, MPC8_DSCF1_BITS, 2);
331  if(t == 64)
332  t += get_bits(gb, 6);
333  bands[i].scf_idx[ch][0] = ((bands[i].scf_idx[ch][2] + t - 25) & 0x7F) - 6;
334  }
335  for(j = 0; j < 2; j++){
336  if((bands[i].scfi[ch] << j) & 2)
337  bands[i].scf_idx[ch][j + 1] = bands[i].scf_idx[ch][j];
338  else{
339  t = get_vlc2(gb, dscf_vlc[0].table, MPC8_DSCF0_BITS, 2);
340  if(t == 31)
341  t = 64 + get_bits(gb, 6);
342  bands[i].scf_idx[ch][j + 1] = ((bands[i].scf_idx[ch][j] + t - 25) & 0x7F) - 6;
343  }
344  }
345  }
346  }
347 
348  for(i = 0, off = 0; i < maxband; i++, off += SAMPLES_PER_BAND){
349  for(ch = 0; ch < 2; ch++){
350  res = bands[i].res[ch];
351  switch(res){
352  case -1:
353  for(j = 0; j < SAMPLES_PER_BAND; j++)
354  c->Q[ch][off + j] = (av_lfg_get(&c->rnd) & 0x3FC) - 510;
355  break;
356  case 0:
357  break;
358  case 1:
359  for(j = 0; j < SAMPLES_PER_BAND; j += SAMPLES_PER_BAND / 2){
360  cnt = get_vlc2(gb, q1_vlc.table, MPC8_Q1_BITS, 2);
361  t = mpc8_get_mask(gb, 18, cnt);
362  for(k = 0; k < SAMPLES_PER_BAND / 2; k++, t <<= 1)
363  c->Q[ch][off + j + k] = (t & 0x20000) ? (get_bits1(gb) << 1) - 1 : 0;
364  }
365  break;
366  case 2:
367  cnt = 6;//2*mpc8_thres[res]
368  for(j = 0; j < SAMPLES_PER_BAND; j += 3){
369  t = get_vlc2(gb, q2_vlc[cnt > 3].table, MPC8_Q2_BITS, 2);
370  c->Q[ch][off + j + 0] = mpc8_idx50[t];
371  c->Q[ch][off + j + 1] = mpc8_idx51[t];
372  c->Q[ch][off + j + 2] = mpc8_idx52[t];
373  cnt = (cnt >> 1) + mpc8_huffq2[t];
374  }
375  break;
376  case 3:
377  case 4:
378  for(j = 0; j < SAMPLES_PER_BAND; j += 2){
379  t = get_vlc2(gb, q3_vlc[res - 3].table, MPC8_Q3_BITS, 2) + q3_offsets[res - 3];
380  c->Q[ch][off + j + 1] = t >> 4;
381  c->Q[ch][off + j + 0] = (t & 8) ? (t & 0xF) - 16 : (t & 0xF);
382  }
383  break;
384  case 5:
385  case 6:
386  case 7:
387  case 8:
388  cnt = 2 * mpc8_thres[res];
389  for(j = 0; j < SAMPLES_PER_BAND; j++){
390  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];
391  c->Q[ch][off + j] = t;
392  cnt = (cnt >> 1) + FFABS(c->Q[ch][off + j]);
393  }
394  break;
395  default:
396  for(j = 0; j < SAMPLES_PER_BAND; j++){
397  c->Q[ch][off + j] = get_vlc2(gb, q9up_vlc.table, MPC8_Q9UP_BITS, 2);
398  if(res != 9){
399  c->Q[ch][off + j] <<= res - 9;
400  c->Q[ch][off + j] |= get_bits(gb, res - 9);
401  }
402  c->Q[ch][off + j] -= (1 << (res - 2)) - 1;
403  }
404  }
405  }
406  }
407 
408  ff_mpc_dequantize_and_synth(c, maxband, c->frame.data[0], avctx->channels);
409 
410  c->cur_frame++;
411 
413  if(c->cur_frame >= c->frames)
414  c->cur_frame = 0;
415 
416  *got_frame_ptr = 1;
417  *(AVFrame *)data = c->frame;
418 
419  return c->cur_frame ? c->last_bits_used >> 3 : buf_size;
420 }
421 
423  .name = "mpc8",
424  .type = AVMEDIA_TYPE_AUDIO,
425  .id = CODEC_ID_MUSEPACK8,
426  .priv_data_size = sizeof(MPCContext),
429  .capabilities = CODEC_CAP_DR1,
430  .long_name = NULL_IF_CONFIG_SMALL("Musepack SV8"),
431 };