2 * DCA compatible decoder
3 * Copyright (C) 2004 Gildas Bazin
4 * Copyright (C) 2004 Benjamin Zores
5 * Copyright (C) 2006 Benjamin Larsson
6 * Copyright (C) 2007 Konstantin Shishkov
8 * This file is part of FFmpeg.
10 * FFmpeg is free software; you can redistribute it and/or
11 * modify it under the terms of the GNU Lesser General Public
12 * License as published by the Free Software Foundation; either
13 * version 2.1 of the License, or (at your option) any later version.
15 * FFmpeg is distributed in the hope that it will be useful,
16 * but WITHOUT ANY WARRANTY; without even the implied warranty of
17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
18 * Lesser General Public License for more details.
20 * You should have received a copy of the GNU Lesser General Public
21 * License along with FFmpeg; if not, write to the Free Software
22 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
29 #include "libavutil/channel_layout.h"
30 #include "libavutil/common.h"
31 #include "libavutil/float_dsp.h"
32 #include "libavutil/internal.h"
33 #include "libavutil/intreadwrite.h"
34 #include "libavutil/mathematics.h"
35 #include "libavutil/opt.h"
36 #include "libavutil/samplefmt.h"
44 #include "fmtconvert.h"
48 #include "synth_filter.h"
69 enum DCAXxchSpeakerMask {
70 DCA_XXCH_FRONT_CENTER = 0x0000001,
71 DCA_XXCH_FRONT_LEFT = 0x0000002,
72 DCA_XXCH_FRONT_RIGHT = 0x0000004,
73 DCA_XXCH_SIDE_REAR_LEFT = 0x0000008,
74 DCA_XXCH_SIDE_REAR_RIGHT = 0x0000010,
75 DCA_XXCH_LFE1 = 0x0000020,
76 DCA_XXCH_REAR_CENTER = 0x0000040,
77 DCA_XXCH_SURROUND_REAR_LEFT = 0x0000080,
78 DCA_XXCH_SURROUND_REAR_RIGHT = 0x0000100,
79 DCA_XXCH_SIDE_SURROUND_LEFT = 0x0000200,
80 DCA_XXCH_SIDE_SURROUND_RIGHT = 0x0000400,
81 DCA_XXCH_FRONT_CENTER_LEFT = 0x0000800,
82 DCA_XXCH_FRONT_CENTER_RIGHT = 0x0001000,
83 DCA_XXCH_FRONT_HIGH_LEFT = 0x0002000,
84 DCA_XXCH_FRONT_HIGH_CENTER = 0x0004000,
85 DCA_XXCH_FRONT_HIGH_RIGHT = 0x0008000,
86 DCA_XXCH_LFE2 = 0x0010000,
87 DCA_XXCH_SIDE_FRONT_LEFT = 0x0020000,
88 DCA_XXCH_SIDE_FRONT_RIGHT = 0x0040000,
89 DCA_XXCH_OVERHEAD = 0x0080000,
90 DCA_XXCH_SIDE_HIGH_LEFT = 0x0100000,
91 DCA_XXCH_SIDE_HIGH_RIGHT = 0x0200000,
92 DCA_XXCH_REAR_HIGH_CENTER = 0x0400000,
93 DCA_XXCH_REAR_HIGH_LEFT = 0x0800000,
94 DCA_XXCH_REAR_HIGH_RIGHT = 0x1000000,
95 DCA_XXCH_REAR_LOW_CENTER = 0x2000000,
96 DCA_XXCH_REAR_LOW_LEFT = 0x4000000,
97 DCA_XXCH_REAR_LOW_RIGHT = 0x8000000,
100 #define DCA_DOLBY 101 /* FIXME */
102 #define DCA_CHANNEL_BITS 6
103 #define DCA_CHANNEL_MASK 0x3F
107 #define HEADER_SIZE 14
109 #define DCA_NSYNCAUX 0x9A1105A0
111 static const uint32_t map_xxch_to_native[28] = {
121 AV_CH_SIDE_LEFT, /* side surround left -- dup sur side L */
122 AV_CH_SIDE_RIGHT, /* side surround right -- dup sur side R */
123 AV_CH_FRONT_LEFT_OF_CENTER,
124 AV_CH_FRONT_RIGHT_OF_CENTER,
125 AV_CH_TOP_FRONT_LEFT,
126 AV_CH_TOP_FRONT_CENTER,
127 AV_CH_TOP_FRONT_RIGHT,
128 AV_CH_LOW_FREQUENCY, /* lfe2 -- duplicate lfe1 position */
129 AV_CH_FRONT_LEFT_OF_CENTER, /* side front left -- dup front cntr L */
130 AV_CH_FRONT_RIGHT_OF_CENTER,/* side front right -- dup front cntr R */
131 AV_CH_TOP_CENTER, /* overhead */
132 AV_CH_TOP_FRONT_LEFT, /* side high left -- dup */
133 AV_CH_TOP_FRONT_RIGHT, /* side high right -- dup */
134 AV_CH_TOP_BACK_CENTER,
136 AV_CH_TOP_BACK_RIGHT,
137 AV_CH_BACK_CENTER, /* rear low center -- dup */
138 AV_CH_BACK_LEFT, /* rear low left -- dup */
139 AV_CH_BACK_RIGHT /* read low right -- dup */
142 /* -1 are reserved or unknown */
143 static const int dca_ext_audio_descr_mask[] = {
147 DCA_EXT_XCH | DCA_EXT_X96,
154 /* Tables for mapping dts channel configurations to libavcodec multichannel api.
155 * Some compromises have been made for special configurations. Most configurations
156 * are never used so complete accuracy is not needed.
158 * L = left, R = right, C = center, S = surround, F = front, R = rear, T = total, OV = overhead.
159 * S -> side, when both rear and back are configured move one of them to the side channel
161 * All 2 channel configurations -> AV_CH_LAYOUT_STEREO
163 static const uint64_t dca_core_channel_layout[] = {
164 AV_CH_FRONT_CENTER, ///< 1, A
165 AV_CH_LAYOUT_STEREO, ///< 2, A + B (dual mono)
166 AV_CH_LAYOUT_STEREO, ///< 2, L + R (stereo)
167 AV_CH_LAYOUT_STEREO, ///< 2, (L + R) + (L - R) (sum-difference)
168 AV_CH_LAYOUT_STEREO, ///< 2, LT + RT (left and right total)
169 AV_CH_LAYOUT_STEREO | AV_CH_FRONT_CENTER, ///< 3, C + L + R
170 AV_CH_LAYOUT_STEREO | AV_CH_BACK_CENTER, ///< 3, L + R + S
171 AV_CH_LAYOUT_STEREO | AV_CH_FRONT_CENTER | AV_CH_BACK_CENTER, ///< 4, C + L + R + S
172 AV_CH_LAYOUT_STEREO | AV_CH_SIDE_LEFT | AV_CH_SIDE_RIGHT, ///< 4, L + R + SL + SR
174 AV_CH_LAYOUT_STEREO | AV_CH_FRONT_CENTER | AV_CH_SIDE_LEFT |
175 AV_CH_SIDE_RIGHT, ///< 5, C + L + R + SL + SR
177 AV_CH_LAYOUT_STEREO | AV_CH_SIDE_LEFT | AV_CH_SIDE_RIGHT |
178 AV_CH_FRONT_LEFT_OF_CENTER | AV_CH_FRONT_RIGHT_OF_CENTER, ///< 6, CL + CR + L + R + SL + SR
180 AV_CH_LAYOUT_STEREO | AV_CH_BACK_LEFT | AV_CH_BACK_RIGHT |
181 AV_CH_FRONT_CENTER | AV_CH_BACK_CENTER, ///< 6, C + L + R + LR + RR + OV
183 AV_CH_FRONT_CENTER | AV_CH_FRONT_RIGHT_OF_CENTER |
184 AV_CH_FRONT_LEFT_OF_CENTER | AV_CH_BACK_CENTER |
185 AV_CH_BACK_LEFT | AV_CH_BACK_RIGHT, ///< 6, CF + CR + LF + RF + LR + RR
187 AV_CH_FRONT_LEFT_OF_CENTER | AV_CH_FRONT_CENTER |
188 AV_CH_FRONT_RIGHT_OF_CENTER | AV_CH_LAYOUT_STEREO |
189 AV_CH_SIDE_LEFT | AV_CH_SIDE_RIGHT, ///< 7, CL + C + CR + L + R + SL + SR
191 AV_CH_FRONT_LEFT_OF_CENTER | AV_CH_FRONT_RIGHT_OF_CENTER |
192 AV_CH_LAYOUT_STEREO | AV_CH_SIDE_LEFT | AV_CH_SIDE_RIGHT |
193 AV_CH_BACK_LEFT | AV_CH_BACK_RIGHT, ///< 8, CL + CR + L + R + SL1 + SL2 + SR1 + SR2
195 AV_CH_FRONT_LEFT_OF_CENTER | AV_CH_FRONT_CENTER |
196 AV_CH_FRONT_RIGHT_OF_CENTER | AV_CH_LAYOUT_STEREO |
197 AV_CH_SIDE_LEFT | AV_CH_BACK_CENTER | AV_CH_SIDE_RIGHT, ///< 8, CL + C + CR + L + R + SL + S + SR
200 /** Bit allocation */
201 typedef struct BitAlloc {
202 int offset; ///< code values offset
203 int maxbits[8]; ///< max bits in VLC
204 int wrap; ///< wrap for get_vlc2()
205 VLC vlc[8]; ///< actual codes
208 static BitAlloc dca_bitalloc_index; ///< indexes for samples VLC select
209 static BitAlloc dca_tmode; ///< transition mode VLCs
210 static BitAlloc dca_scalefactor; ///< scalefactor VLCs
211 static BitAlloc dca_smpl_bitalloc[11]; ///< samples VLCs
213 static av_always_inline int get_bitalloc(GetBitContext *gb, BitAlloc *ba,
216 return get_vlc2(gb, ba->vlc[idx].table, ba->vlc[idx].bits, ba->wrap) +
220 static float dca_dmix_code(unsigned code);
222 static av_cold void dca_init_vlcs(void)
224 static int vlcs_initialized = 0;
226 static VLC_TYPE dca_table[23622][2];
228 if (vlcs_initialized)
231 dca_bitalloc_index.offset = 1;
232 dca_bitalloc_index.wrap = 2;
233 for (i = 0; i < 5; i++) {
234 dca_bitalloc_index.vlc[i].table = &dca_table[ff_dca_vlc_offs[i]];
235 dca_bitalloc_index.vlc[i].table_allocated = ff_dca_vlc_offs[i + 1] - ff_dca_vlc_offs[i];
236 init_vlc(&dca_bitalloc_index.vlc[i], bitalloc_12_vlc_bits[i], 12,
237 bitalloc_12_bits[i], 1, 1,
238 bitalloc_12_codes[i], 2, 2, INIT_VLC_USE_NEW_STATIC);
240 dca_scalefactor.offset = -64;
241 dca_scalefactor.wrap = 2;
242 for (i = 0; i < 5; i++) {
243 dca_scalefactor.vlc[i].table = &dca_table[ff_dca_vlc_offs[i + 5]];
244 dca_scalefactor.vlc[i].table_allocated = ff_dca_vlc_offs[i + 6] - ff_dca_vlc_offs[i + 5];
245 init_vlc(&dca_scalefactor.vlc[i], SCALES_VLC_BITS, 129,
246 scales_bits[i], 1, 1,
247 scales_codes[i], 2, 2, INIT_VLC_USE_NEW_STATIC);
249 dca_tmode.offset = 0;
251 for (i = 0; i < 4; i++) {
252 dca_tmode.vlc[i].table = &dca_table[ff_dca_vlc_offs[i + 10]];
253 dca_tmode.vlc[i].table_allocated = ff_dca_vlc_offs[i + 11] - ff_dca_vlc_offs[i + 10];
254 init_vlc(&dca_tmode.vlc[i], tmode_vlc_bits[i], 4,
256 tmode_codes[i], 2, 2, INIT_VLC_USE_NEW_STATIC);
259 for (i = 0; i < 10; i++)
260 for (j = 0; j < 7; j++) {
261 if (!bitalloc_codes[i][j])
263 dca_smpl_bitalloc[i + 1].offset = bitalloc_offsets[i];
264 dca_smpl_bitalloc[i + 1].wrap = 1 + (j > 4);
265 dca_smpl_bitalloc[i + 1].vlc[j].table = &dca_table[ff_dca_vlc_offs[c]];
266 dca_smpl_bitalloc[i + 1].vlc[j].table_allocated = ff_dca_vlc_offs[c + 1] - ff_dca_vlc_offs[c];
268 init_vlc(&dca_smpl_bitalloc[i + 1].vlc[j], bitalloc_maxbits[i][j],
270 bitalloc_bits[i][j], 1, 1,
271 bitalloc_codes[i][j], 2, 2, INIT_VLC_USE_NEW_STATIC);
274 vlcs_initialized = 1;
277 static inline void get_array(GetBitContext *gb, int *dst, int len, int bits)
280 *dst++ = get_bits(gb, bits);
283 static inline int dca_xxch2index(DCAContext *s, int xxch_ch)
287 /* locate channel set containing the channel */
288 for (i = -1, base = 0, mask = (s->xxch_core_spkmask & ~DCA_XXCH_LFE1);
289 i <= s->xxch_chset && !(mask & xxch_ch); mask = s->xxch_spk_masks[++i])
290 base += av_popcount(mask);
292 return base + av_popcount(mask & (xxch_ch - 1));
295 static int dca_parse_audio_coding_header(DCAContext *s, int base_channel,
299 static const float adj_table[4] = { 1.0, 1.1250, 1.2500, 1.4375 };
300 static const int bitlen[11] = { 0, 1, 2, 2, 2, 2, 3, 3, 3, 3, 3 };
301 static const int thr[11] = { 0, 1, 3, 3, 3, 3, 7, 7, 7, 7, 7 };
302 int hdr_pos = 0, hdr_size = 0;
304 int this_chans, acc_mask;
305 int embedded_downmix;
309 /* xxch has arbitrary sized audio coding headers */
311 hdr_pos = get_bits_count(&s->gb);
312 hdr_size = get_bits(&s->gb, 7) + 1;
315 nchans = get_bits(&s->gb, 3) + 1;
316 s->total_channels = nchans + base_channel;
317 s->prim_channels = s->total_channels;
319 /* obtain speaker layout mask & downmix coefficients for XXCH */
321 acc_mask = s->xxch_core_spkmask;
323 this_chans = get_bits(&s->gb, s->xxch_nbits_spk_mask - 6) << 6;
324 s->xxch_spk_masks[s->xxch_chset] = this_chans;
325 s->xxch_chset_nch[s->xxch_chset] = nchans;
327 for (i = 0; i <= s->xxch_chset; i++)
328 acc_mask |= s->xxch_spk_masks[i];
330 /* check for downmixing information */
331 if (get_bits1(&s->gb)) {
332 embedded_downmix = get_bits1(&s->gb);
333 coeff = get_bits(&s->gb, 6);
335 if (coeff<1 || coeff>61) {
336 av_log(s->avctx, AV_LOG_ERROR, "6bit coeff %d is out of range\n", coeff);
337 return AVERROR_INVALIDDATA;
340 scale_factor = -1.0f / dca_dmix_code((coeff<<2)-3);
342 s->xxch_dmix_sf[s->xxch_chset] = scale_factor;
344 for (i = base_channel; i < s->prim_channels; i++) {
345 mask[i] = get_bits(&s->gb, s->xxch_nbits_spk_mask);
348 for (j = base_channel; j < s->prim_channels; j++) {
349 memset(s->xxch_dmix_coeff[j], 0, sizeof(s->xxch_dmix_coeff[0]));
350 s->xxch_dmix_embedded |= (embedded_downmix << j);
351 for (i = 0; i < s->xxch_nbits_spk_mask; i++) {
352 if (mask[j] & (1 << i)) {
353 if ((1 << i) == DCA_XXCH_LFE1) {
354 av_log(s->avctx, AV_LOG_WARNING,
355 "DCA-XXCH: dmix to LFE1 not supported.\n");
359 coeff = get_bits(&s->gb, 7);
360 ichan = dca_xxch2index(s, 1 << i);
361 if ((coeff&63)<1 || (coeff&63)>61) {
362 av_log(s->avctx, AV_LOG_ERROR, "7bit coeff %d is out of range\n", coeff);
363 return AVERROR_INVALIDDATA;
365 s->xxch_dmix_coeff[j][ichan] = dca_dmix_code((coeff<<2)-3);
372 if (s->prim_channels > DCA_PRIM_CHANNELS_MAX)
373 s->prim_channels = DCA_PRIM_CHANNELS_MAX;
375 for (i = base_channel; i < s->prim_channels; i++) {
376 s->subband_activity[i] = get_bits(&s->gb, 5) + 2;
377 if (s->subband_activity[i] > DCA_SUBBANDS)
378 s->subband_activity[i] = DCA_SUBBANDS;
380 for (i = base_channel; i < s->prim_channels; i++) {
381 s->vq_start_subband[i] = get_bits(&s->gb, 5) + 1;
382 if (s->vq_start_subband[i] > DCA_SUBBANDS)
383 s->vq_start_subband[i] = DCA_SUBBANDS;
385 get_array(&s->gb, s->joint_intensity + base_channel, s->prim_channels - base_channel, 3);
386 get_array(&s->gb, s->transient_huffman + base_channel, s->prim_channels - base_channel, 2);
387 get_array(&s->gb, s->scalefactor_huffman + base_channel, s->prim_channels - base_channel, 3);
388 get_array(&s->gb, s->bitalloc_huffman + base_channel, s->prim_channels - base_channel, 3);
390 /* Get codebooks quantization indexes */
392 memset(s->quant_index_huffman, 0, sizeof(s->quant_index_huffman));
393 for (j = 1; j < 11; j++)
394 for (i = base_channel; i < s->prim_channels; i++)
395 s->quant_index_huffman[i][j] = get_bits(&s->gb, bitlen[j]);
397 /* Get scale factor adjustment */
398 for (j = 0; j < 11; j++)
399 for (i = base_channel; i < s->prim_channels; i++)
400 s->scalefactor_adj[i][j] = 1;
402 for (j = 1; j < 11; j++)
403 for (i = base_channel; i < s->prim_channels; i++)
404 if (s->quant_index_huffman[i][j] < thr[j])
405 s->scalefactor_adj[i][j] = adj_table[get_bits(&s->gb, 2)];
408 if (s->crc_present) {
409 /* Audio header CRC check */
410 get_bits(&s->gb, 16);
413 /* Skip to the end of the header, also ignore CRC if present */
414 i = get_bits_count(&s->gb);
415 if (hdr_pos + 8 * hdr_size > i)
416 skip_bits_long(&s->gb, hdr_pos + 8 * hdr_size - i);
419 s->current_subframe = 0;
420 s->current_subsubframe = 0;
425 static int dca_parse_frame_header(DCAContext *s)
427 init_get_bits(&s->gb, s->dca_buffer, s->dca_buffer_size * 8);
430 skip_bits_long(&s->gb, 32);
433 s->frame_type = get_bits(&s->gb, 1);
434 s->samples_deficit = get_bits(&s->gb, 5) + 1;
435 s->crc_present = get_bits(&s->gb, 1);
436 s->sample_blocks = get_bits(&s->gb, 7) + 1;
437 s->frame_size = get_bits(&s->gb, 14) + 1;
438 if (s->frame_size < 95)
439 return AVERROR_INVALIDDATA;
440 s->amode = get_bits(&s->gb, 6);
441 s->sample_rate = avpriv_dca_sample_rates[get_bits(&s->gb, 4)];
443 return AVERROR_INVALIDDATA;
444 s->bit_rate_index = get_bits(&s->gb, 5);
445 s->bit_rate = ff_dca_bit_rates[s->bit_rate_index];
447 return AVERROR_INVALIDDATA;
449 skip_bits1(&s->gb); // always 0 (reserved, cf. ETSI TS 102 114 V1.4.1)
450 s->dynrange = get_bits(&s->gb, 1);
451 s->timestamp = get_bits(&s->gb, 1);
452 s->aux_data = get_bits(&s->gb, 1);
453 s->hdcd = get_bits(&s->gb, 1);
454 s->ext_descr = get_bits(&s->gb, 3);
455 s->ext_coding = get_bits(&s->gb, 1);
456 s->aspf = get_bits(&s->gb, 1);
457 s->lfe = get_bits(&s->gb, 2);
458 s->predictor_history = get_bits(&s->gb, 1);
462 av_log(s->avctx, AV_LOG_ERROR, "Invalid LFE value: %d\n", s->lfe);
463 return AVERROR_INVALIDDATA;
466 /* TODO: check CRC */
468 s->header_crc = get_bits(&s->gb, 16);
470 s->multirate_inter = get_bits(&s->gb, 1);
471 s->version = get_bits(&s->gb, 4);
472 s->copy_history = get_bits(&s->gb, 2);
473 s->source_pcm_res = get_bits(&s->gb, 3);
474 s->front_sum = get_bits(&s->gb, 1);
475 s->surround_sum = get_bits(&s->gb, 1);
476 s->dialog_norm = get_bits(&s->gb, 4);
478 /* FIXME: channels mixing levels */
479 s->output = s->amode;
481 s->output |= DCA_LFE;
483 /* Primary audio coding header */
484 s->subframes = get_bits(&s->gb, 4) + 1;
486 return dca_parse_audio_coding_header(s, 0, 0);
489 static inline int get_scale(GetBitContext *gb, int level, int value, int log2range)
492 /* huffman encoded */
493 value += get_bitalloc(gb, &dca_scalefactor, level);
494 value = av_clip(value, 0, (1 << log2range) - 1);
495 } else if (level < 8) {
496 if (level + 1 > log2range) {
497 skip_bits(gb, level + 1 - log2range);
498 value = get_bits(gb, log2range);
500 value = get_bits(gb, level + 1);
506 static int dca_subframe_header(DCAContext *s, int base_channel, int block_index)
508 /* Primary audio coding side information */
511 if (get_bits_left(&s->gb) < 0)
512 return AVERROR_INVALIDDATA;
515 s->subsubframes[s->current_subframe] = get_bits(&s->gb, 2) + 1;
516 s->partial_samples[s->current_subframe] = get_bits(&s->gb, 3);
519 for (j = base_channel; j < s->prim_channels; j++) {
520 for (k = 0; k < s->subband_activity[j]; k++)
521 s->prediction_mode[j][k] = get_bits(&s->gb, 1);
524 /* Get prediction codebook */
525 for (j = base_channel; j < s->prim_channels; j++) {
526 for (k = 0; k < s->subband_activity[j]; k++) {
527 if (s->prediction_mode[j][k] > 0) {
528 /* (Prediction coefficient VQ address) */
529 s->prediction_vq[j][k] = get_bits(&s->gb, 12);
534 /* Bit allocation index */
535 for (j = base_channel; j < s->prim_channels; j++) {
536 for (k = 0; k < s->vq_start_subband[j]; k++) {
537 if (s->bitalloc_huffman[j] == 6)
538 s->bitalloc[j][k] = get_bits(&s->gb, 5);
539 else if (s->bitalloc_huffman[j] == 5)
540 s->bitalloc[j][k] = get_bits(&s->gb, 4);
541 else if (s->bitalloc_huffman[j] == 7) {
542 av_log(s->avctx, AV_LOG_ERROR,
543 "Invalid bit allocation index\n");
544 return AVERROR_INVALIDDATA;
547 get_bitalloc(&s->gb, &dca_bitalloc_index, s->bitalloc_huffman[j]);
550 if (s->bitalloc[j][k] > 26) {
551 av_dlog(s->avctx, "bitalloc index [%i][%i] too big (%i)\n",
552 j, k, s->bitalloc[j][k]);
553 return AVERROR_INVALIDDATA;
558 /* Transition mode */
559 for (j = base_channel; j < s->prim_channels; j++) {
560 for (k = 0; k < s->subband_activity[j]; k++) {
561 s->transition_mode[j][k] = 0;
562 if (s->subsubframes[s->current_subframe] > 1 &&
563 k < s->vq_start_subband[j] && s->bitalloc[j][k] > 0) {
564 s->transition_mode[j][k] =
565 get_bitalloc(&s->gb, &dca_tmode, s->transient_huffman[j]);
570 if (get_bits_left(&s->gb) < 0)
571 return AVERROR_INVALIDDATA;
573 for (j = base_channel; j < s->prim_channels; j++) {
574 const uint32_t *scale_table;
575 int scale_sum, log_size;
577 memset(s->scale_factor[j], 0,
578 s->subband_activity[j] * sizeof(s->scale_factor[0][0][0]) * 2);
580 if (s->scalefactor_huffman[j] == 6) {
581 scale_table = ff_dca_scale_factor_quant7;
584 scale_table = ff_dca_scale_factor_quant6;
588 /* When huffman coded, only the difference is encoded */
591 for (k = 0; k < s->subband_activity[j]; k++) {
592 if (k >= s->vq_start_subband[j] || s->bitalloc[j][k] > 0) {
593 scale_sum = get_scale(&s->gb, s->scalefactor_huffman[j], scale_sum, log_size);
594 s->scale_factor[j][k][0] = scale_table[scale_sum];
597 if (k < s->vq_start_subband[j] && s->transition_mode[j][k]) {
598 /* Get second scale factor */
599 scale_sum = get_scale(&s->gb, s->scalefactor_huffman[j], scale_sum, log_size);
600 s->scale_factor[j][k][1] = scale_table[scale_sum];
605 /* Joint subband scale factor codebook select */
606 for (j = base_channel; j < s->prim_channels; j++) {
607 /* Transmitted only if joint subband coding enabled */
608 if (s->joint_intensity[j] > 0)
609 s->joint_huff[j] = get_bits(&s->gb, 3);
612 if (get_bits_left(&s->gb) < 0)
613 return AVERROR_INVALIDDATA;
615 /* Scale factors for joint subband coding */
616 for (j = base_channel; j < s->prim_channels; j++) {
619 /* Transmitted only if joint subband coding enabled */
620 if (s->joint_intensity[j] > 0) {
622 source_channel = s->joint_intensity[j] - 1;
624 /* When huffman coded, only the difference is encoded
625 * (is this valid as well for joint scales ???) */
627 for (k = s->subband_activity[j]; k < s->subband_activity[source_channel]; k++) {
628 scale = get_scale(&s->gb, s->joint_huff[j], 64 /* bias */, 7);
629 s->joint_scale_factor[j][k] = scale; /*joint_scale_table[scale]; */
632 if (!(s->debug_flag & 0x02)) {
633 av_log(s->avctx, AV_LOG_DEBUG,
634 "Joint stereo coding not supported\n");
635 s->debug_flag |= 0x02;
640 /* Dynamic range coefficient */
641 if (!base_channel && s->dynrange)
642 s->dynrange_coef = get_bits(&s->gb, 8);
644 /* Side information CRC check word */
645 if (s->crc_present) {
646 get_bits(&s->gb, 16);
650 * Primary audio data arrays
653 /* VQ encoded high frequency subbands */
654 for (j = base_channel; j < s->prim_channels; j++)
655 for (k = s->vq_start_subband[j]; k < s->subband_activity[j]; k++)
656 /* 1 vector -> 32 samples */
657 s->high_freq_vq[j][k] = get_bits(&s->gb, 10);
659 /* Low frequency effect data */
660 if (!base_channel && s->lfe) {
663 int lfe_samples = 2 * s->lfe * (4 + block_index);
664 int lfe_end_sample = 2 * s->lfe * (4 + block_index + s->subsubframes[s->current_subframe]);
667 for (j = lfe_samples; j < lfe_end_sample; j++) {
668 /* Signed 8 bits int */
669 s->lfe_data[j] = get_sbits(&s->gb, 8);
672 /* Scale factor index */
673 quant7 = get_bits(&s->gb, 8);
675 avpriv_request_sample(s->avctx, "LFEScaleIndex larger than 127");
676 return AVERROR_INVALIDDATA;
678 s->lfe_scale_factor = ff_dca_scale_factor_quant7[quant7];
680 /* Quantization step size * scale factor */
681 lfe_scale = 0.035 * s->lfe_scale_factor;
683 for (j = lfe_samples; j < lfe_end_sample; j++)
684 s->lfe_data[j] *= lfe_scale;
690 static void qmf_32_subbands(DCAContext *s, int chans,
691 float samples_in[32][8], float *samples_out,
694 const float *prCoeff;
696 int sb_act = s->subband_activity[chans];
698 scale *= sqrt(1 / 8.0);
701 if (!s->multirate_inter) /* Non-perfect reconstruction */
702 prCoeff = ff_dca_fir_32bands_nonperfect;
703 else /* Perfect reconstruction */
704 prCoeff = ff_dca_fir_32bands_perfect;
706 s->dcadsp.qmf_32_subbands(samples_in, sb_act, &s->synth, &s->imdct,
707 s->subband_fir_hist[chans],
708 &s->hist_index[chans],
709 s->subband_fir_noidea[chans], prCoeff,
710 samples_out, s->raXin, scale);
713 static void lfe_interpolation_fir(DCAContext *s, int decimation_select,
714 int num_deci_sample, float *samples_in,
717 /* samples_in: An array holding decimated samples.
718 * Samples in current subframe starts from samples_in[0],
719 * while samples_in[-1], samples_in[-2], ..., stores samples
720 * from last subframe as history.
722 * samples_out: An array holding interpolated samples
726 const float *prCoeff;
729 /* Select decimation filter */
730 if (decimation_select == 1) {
732 prCoeff = ff_dca_lfe_fir_128;
735 prCoeff = ff_dca_lfe_fir_64;
738 for (deciindex = 0; deciindex < num_deci_sample; deciindex++) {
739 s->dcadsp.lfe_fir[idx](samples_out, samples_in, prCoeff);
741 samples_out += 2 * 32 * (1 + idx);
745 /* downmixing routines */
746 #define MIX_REAR1(samples, s1, rs, coef) \
747 samples[0][i] += samples[s1][i] * coef[rs][0]; \
748 samples[1][i] += samples[s1][i] * coef[rs][1];
750 #define MIX_REAR2(samples, s1, s2, rs, coef) \
751 samples[0][i] += samples[s1][i] * coef[rs][0] + samples[s2][i] * coef[rs + 1][0]; \
752 samples[1][i] += samples[s1][i] * coef[rs][1] + samples[s2][i] * coef[rs + 1][1];
754 #define MIX_FRONT3(samples, coef) \
758 samples[0][i] = t * coef[0][0] + u * coef[1][0] + v * coef[2][0]; \
759 samples[1][i] = t * coef[0][1] + u * coef[1][1] + v * coef[2][1];
761 #define DOWNMIX_TO_STEREO(op1, op2) \
762 for (i = 0; i < 256; i++) { \
767 static void dca_downmix(float **samples, int srcfmt, int lfe_present,
768 float coef[DCA_PRIM_CHANNELS_MAX + 1][2],
769 const int8_t *channel_mapping)
771 int c, l, r, sl, sr, s;
778 av_log(NULL, AV_LOG_ERROR, "Not implemented!\n");
782 case DCA_STEREO_TOTAL:
783 case DCA_STEREO_SUMDIFF:
786 c = channel_mapping[0];
787 l = channel_mapping[1];
788 r = channel_mapping[2];
789 DOWNMIX_TO_STEREO(MIX_FRONT3(samples, coef), );
792 s = channel_mapping[2];
793 DOWNMIX_TO_STEREO(MIX_REAR1(samples, s, 2, coef), );
796 c = channel_mapping[0];
797 l = channel_mapping[1];
798 r = channel_mapping[2];
799 s = channel_mapping[3];
800 DOWNMIX_TO_STEREO(MIX_FRONT3(samples, coef),
801 MIX_REAR1(samples, s, 3, coef));
804 sl = channel_mapping[2];
805 sr = channel_mapping[3];
806 DOWNMIX_TO_STEREO(MIX_REAR2(samples, sl, sr, 2, coef), );
809 c = channel_mapping[0];
810 l = channel_mapping[1];
811 r = channel_mapping[2];
812 sl = channel_mapping[3];
813 sr = channel_mapping[4];
814 DOWNMIX_TO_STEREO(MIX_FRONT3(samples, coef),
815 MIX_REAR2(samples, sl, sr, 3, coef));
819 int lf_buf = ff_dca_lfe_index[srcfmt];
820 int lf_idx = ff_dca_channels[srcfmt];
821 for (i = 0; i < 256; i++) {
822 samples[0][i] += samples[lf_buf][i] * coef[lf_idx][0];
823 samples[1][i] += samples[lf_buf][i] * coef[lf_idx][1];
828 #ifndef decode_blockcodes
829 /* Very compact version of the block code decoder that does not use table
830 * look-up but is slightly slower */
831 static int decode_blockcode(int code, int levels, int32_t *values)
834 int offset = (levels - 1) >> 1;
836 for (i = 0; i < 4; i++) {
837 int div = FASTDIV(code, levels);
838 values[i] = code - offset - div * levels;
845 static int decode_blockcodes(int code1, int code2, int levels, int32_t *values)
847 return decode_blockcode(code1, levels, values) |
848 decode_blockcode(code2, levels, values + 4);
852 static const uint8_t abits_sizes[7] = { 7, 10, 12, 13, 15, 17, 19 };
853 static const uint8_t abits_levels[7] = { 3, 5, 7, 9, 13, 17, 25 };
855 static int dca_subsubframe(DCAContext *s, int base_channel, int block_index)
858 int subsubframe = s->current_subsubframe;
860 const float *quant_step_table;
863 float (*subband_samples)[DCA_SUBBANDS][8] = s->subband_samples[block_index];
864 LOCAL_ALIGNED_16(int32_t, block, [8 * DCA_SUBBANDS]);
870 /* Select quantization step size table */
871 if (s->bit_rate_index == 0x1f)
872 quant_step_table = ff_dca_lossless_quant_d;
874 quant_step_table = ff_dca_lossy_quant_d;
876 for (k = base_channel; k < s->prim_channels; k++) {
877 float rscale[DCA_SUBBANDS];
879 if (get_bits_left(&s->gb) < 0)
880 return AVERROR_INVALIDDATA;
882 for (l = 0; l < s->vq_start_subband[k]; l++) {
885 /* Select the mid-tread linear quantizer */
886 int abits = s->bitalloc[k][l];
888 float quant_step_size = quant_step_table[abits];
891 * Determine quantization index code book and its type
894 /* Select quantization index code book */
895 int sel = s->quant_index_huffman[k][abits];
898 * Extract bits from the bit stream
902 memset(block + 8 * l, 0, 8 * sizeof(block[0]));
904 /* Deal with transients */
905 int sfi = s->transition_mode[k][l] && subsubframe >= s->transition_mode[k][l];
906 rscale[l] = quant_step_size * s->scale_factor[k][l][sfi] *
907 s->scalefactor_adj[k][sel];
909 if (abits >= 11 || !dca_smpl_bitalloc[abits].vlc[sel].table) {
912 int block_code1, block_code2, size, levels, err;
914 size = abits_sizes[abits - 1];
915 levels = abits_levels[abits - 1];
917 block_code1 = get_bits(&s->gb, size);
918 block_code2 = get_bits(&s->gb, size);
919 err = decode_blockcodes(block_code1, block_code2,
920 levels, block + 8 * l);
922 av_log(s->avctx, AV_LOG_ERROR,
923 "ERROR: block code look-up failed\n");
924 return AVERROR_INVALIDDATA;
928 for (m = 0; m < 8; m++)
929 block[8 * l + m] = get_sbits(&s->gb, abits - 3);
933 for (m = 0; m < 8; m++)
934 block[8 * l + m] = get_bitalloc(&s->gb,
935 &dca_smpl_bitalloc[abits], sel);
940 s->fmt_conv.int32_to_float_fmul_array8(&s->fmt_conv, subband_samples[k][0],
941 block, rscale, 8 * s->vq_start_subband[k]);
943 for (l = 0; l < s->vq_start_subband[k]; l++) {
946 * Inverse ADPCM if in prediction mode
948 if (s->prediction_mode[k][l]) {
950 if (s->predictor_history)
951 subband_samples[k][l][0] += (ff_dca_adpcm_vb[s->prediction_vq[k][l]][0] *
952 s->subband_samples_hist[k][l][3] +
953 ff_dca_adpcm_vb[s->prediction_vq[k][l]][1] *
954 s->subband_samples_hist[k][l][2] +
955 ff_dca_adpcm_vb[s->prediction_vq[k][l]][2] *
956 s->subband_samples_hist[k][l][1] +
957 ff_dca_adpcm_vb[s->prediction_vq[k][l]][3] *
958 s->subband_samples_hist[k][l][0]) *
960 for (m = 1; m < 8; m++) {
961 float sum = ff_dca_adpcm_vb[s->prediction_vq[k][l]][0] *
962 subband_samples[k][l][m - 1];
963 for (n = 2; n <= 4; n++)
965 sum += ff_dca_adpcm_vb[s->prediction_vq[k][l]][n - 1] *
966 subband_samples[k][l][m - n];
967 else if (s->predictor_history)
968 sum += ff_dca_adpcm_vb[s->prediction_vq[k][l]][n - 1] *
969 s->subband_samples_hist[k][l][m - n + 4];
970 subband_samples[k][l][m] += sum * (1.0f / 8192);
976 * Decode VQ encoded high frequencies
978 if (s->subband_activity[k] > s->vq_start_subband[k]) {
979 if (!(s->debug_flag & 0x01)) {
980 av_log(s->avctx, AV_LOG_DEBUG,
981 "Stream with high frequencies VQ coding\n");
982 s->debug_flag |= 0x01;
984 s->dcadsp.decode_hf(subband_samples[k], s->high_freq_vq[k],
985 ff_dca_high_freq_vq, subsubframe * 8,
986 s->scale_factor[k], s->vq_start_subband[k],
987 s->subband_activity[k]);
991 /* Check for DSYNC after subsubframe */
992 if (s->aspf || subsubframe == s->subsubframes[s->current_subframe] - 1) {
993 if (get_bits(&s->gb, 16) != 0xFFFF) {
994 av_log(s->avctx, AV_LOG_ERROR, "Didn't get subframe DSYNC\n");
995 return AVERROR_INVALIDDATA;
999 /* Backup predictor history for adpcm */
1000 for (k = base_channel; k < s->prim_channels; k++)
1001 for (l = 0; l < s->vq_start_subband[k]; l++)
1002 AV_COPY128(s->subband_samples_hist[k][l], &subband_samples[k][l][4]);
1007 static int dca_filter_channels(DCAContext *s, int block_index)
1009 float (*subband_samples)[DCA_SUBBANDS][8] = s->subband_samples[block_index];
1012 /* 32 subbands QMF */
1013 for (k = 0; k < s->prim_channels; k++) {
1014 if (s->channel_order_tab[k] >= 0)
1015 qmf_32_subbands(s, k, subband_samples[k],
1016 s->samples_chanptr[s->channel_order_tab[k]],
1017 M_SQRT1_2 / 32768.0);
1020 /* Generate LFE samples for this subsubframe FIXME!!! */
1022 lfe_interpolation_fir(s, s->lfe, 2 * s->lfe,
1023 s->lfe_data + 2 * s->lfe * (block_index + 4),
1024 s->samples_chanptr[s->lfe_index]);
1025 /* Outputs 20bits pcm samples */
1028 /* Downmixing to Stereo */
1029 if (s->prim_channels + !!s->lfe > 2 &&
1030 s->avctx->request_channel_layout == AV_CH_LAYOUT_STEREO) {
1031 dca_downmix(s->samples_chanptr, s->amode, !!s->lfe, s->downmix_coef,
1032 s->channel_order_tab);
1038 static int dca_subframe_footer(DCAContext *s, int base_channel)
1040 int in, out, aux_data_count, aux_data_end, reserved;
1044 * Unpack optional information
1047 /* presumably optional information only appears in the core? */
1048 if (!base_channel) {
1050 skip_bits_long(&s->gb, 32);
1053 aux_data_count = get_bits(&s->gb, 6);
1056 skip_bits_long(&s->gb, (-get_bits_count(&s->gb)) & 31);
1058 aux_data_end = 8 * aux_data_count + get_bits_count(&s->gb);
1060 if ((nsyncaux = get_bits_long(&s->gb, 32)) != DCA_NSYNCAUX) {
1061 av_log(s->avctx, AV_LOG_ERROR, "nSYNCAUX mismatch %#"PRIx32"\n",
1063 return AVERROR_INVALIDDATA;
1066 if (get_bits1(&s->gb)) { // bAUXTimeStampFlag
1067 avpriv_request_sample(s->avctx,
1068 "Auxiliary Decode Time Stamp Flag");
1070 skip_bits(&s->gb, (-get_bits_count(&s->gb)) & 4);
1071 // 44 bits: nMSByte (8), nMarker (4), nLSByte (28), nMarker (4)
1072 skip_bits_long(&s->gb, 44);
1075 if ((s->core_downmix = get_bits1(&s->gb))) {
1076 int am = get_bits(&s->gb, 3);
1079 s->core_downmix_amode = DCA_MONO;
1082 s->core_downmix_amode = DCA_STEREO;
1085 s->core_downmix_amode = DCA_STEREO_TOTAL;
1088 s->core_downmix_amode = DCA_3F;
1091 s->core_downmix_amode = DCA_2F1R;
1094 s->core_downmix_amode = DCA_2F2R;
1097 s->core_downmix_amode = DCA_3F1R;
1100 av_log(s->avctx, AV_LOG_ERROR,
1101 "Invalid mode %d for embedded downmix coefficients\n",
1103 return AVERROR_INVALIDDATA;
1105 for (out = 0; out < ff_dca_channels[s->core_downmix_amode]; out++) {
1106 for (in = 0; in < s->prim_channels + !!s->lfe; in++) {
1107 uint16_t tmp = get_bits(&s->gb, 9);
1108 if ((tmp & 0xFF) > 241) {
1109 av_log(s->avctx, AV_LOG_ERROR,
1110 "Invalid downmix coefficient code %"PRIu16"\n",
1112 return AVERROR_INVALIDDATA;
1114 s->core_downmix_codes[in][out] = tmp;
1119 align_get_bits(&s->gb); // byte align
1120 skip_bits(&s->gb, 16); // nAUXCRC16
1122 // additional data (reserved, cf. ETSI TS 102 114 V1.4.1)
1123 if ((reserved = (aux_data_end - get_bits_count(&s->gb))) < 0) {
1124 av_log(s->avctx, AV_LOG_ERROR,
1125 "Overread auxiliary data by %d bits\n", -reserved);
1126 return AVERROR_INVALIDDATA;
1127 } else if (reserved) {
1128 avpriv_request_sample(s->avctx,
1129 "Core auxiliary data reserved content");
1130 skip_bits_long(&s->gb, reserved);
1134 if (s->crc_present && s->dynrange)
1135 get_bits(&s->gb, 16);
1142 * Decode a dca frame block
1144 * @param s pointer to the DCAContext
1147 static int dca_decode_block(DCAContext *s, int base_channel, int block_index)
1152 if (s->current_subframe >= s->subframes) {
1153 av_log(s->avctx, AV_LOG_DEBUG, "check failed: %i>%i",
1154 s->current_subframe, s->subframes);
1155 return AVERROR_INVALIDDATA;
1158 if (!s->current_subsubframe) {
1159 /* Read subframe header */
1160 if ((ret = dca_subframe_header(s, base_channel, block_index)))
1164 /* Read subsubframe */
1165 if ((ret = dca_subsubframe(s, base_channel, block_index)))
1169 s->current_subsubframe++;
1170 if (s->current_subsubframe >= s->subsubframes[s->current_subframe]) {
1171 s->current_subsubframe = 0;
1172 s->current_subframe++;
1174 if (s->current_subframe >= s->subframes) {
1175 /* Read subframe footer */
1176 if ((ret = dca_subframe_footer(s, base_channel)))
1183 int ff_dca_xbr_parse_frame(DCAContext *s)
1185 int scale_table_high[DCA_CHSET_CHANS_MAX][DCA_SUBBANDS][2];
1186 int active_bands[DCA_CHSETS_MAX][DCA_CHSET_CHANS_MAX];
1187 int abits_high[DCA_CHSET_CHANS_MAX][DCA_SUBBANDS];
1188 int anctemp[DCA_CHSET_CHANS_MAX];
1189 int chset_fsize[DCA_CHSETS_MAX];
1190 int n_xbr_ch[DCA_CHSETS_MAX];
1191 int hdr_size, num_chsets, xbr_tmode, hdr_pos;
1192 int i, j, k, l, chset, chan_base;
1194 av_log(s->avctx, AV_LOG_DEBUG, "DTS-XBR: decoding XBR extension\n");
1196 /* get bit position of sync header */
1197 hdr_pos = get_bits_count(&s->gb) - 32;
1199 hdr_size = get_bits(&s->gb, 6) + 1;
1200 num_chsets = get_bits(&s->gb, 2) + 1;
1202 for(i = 0; i < num_chsets; i++)
1203 chset_fsize[i] = get_bits(&s->gb, 14) + 1;
1205 xbr_tmode = get_bits1(&s->gb);
1207 for(i = 0; i < num_chsets; i++) {
1208 n_xbr_ch[i] = get_bits(&s->gb, 3) + 1;
1209 k = get_bits(&s->gb, 2) + 5;
1210 for(j = 0; j < n_xbr_ch[i]; j++)
1211 active_bands[i][j] = get_bits(&s->gb, k) + 1;
1214 /* skip to the end of the header */
1215 i = get_bits_count(&s->gb);
1216 if(hdr_pos + hdr_size * 8 > i)
1217 skip_bits_long(&s->gb, hdr_pos + hdr_size * 8 - i);
1219 /* loop over the channel data sets */
1220 /* only decode as many channels as we've decoded base data for */
1221 for(chset = 0, chan_base = 0;
1222 chset < num_chsets && chan_base + n_xbr_ch[chset] <= s->prim_channels;
1223 chan_base += n_xbr_ch[chset++]) {
1224 int start_posn = get_bits_count(&s->gb);
1225 int subsubframe = 0;
1228 /* loop over subframes */
1229 for (k = 0; k < (s->sample_blocks / 8); k++) {
1230 /* parse header if we're on first subsubframe of a block */
1231 if(subsubframe == 0) {
1232 /* Parse subframe header */
1233 for(i = 0; i < n_xbr_ch[chset]; i++) {
1234 anctemp[i] = get_bits(&s->gb, 2) + 2;
1237 for(i = 0; i < n_xbr_ch[chset]; i++) {
1238 get_array(&s->gb, abits_high[i], active_bands[chset][i], anctemp[i]);
1241 for(i = 0; i < n_xbr_ch[chset]; i++) {
1242 anctemp[i] = get_bits(&s->gb, 3);
1243 if(anctemp[i] < 1) {
1244 av_log(s->avctx, AV_LOG_ERROR, "DTS-XBR: SYNC ERROR\n");
1245 return AVERROR_INVALIDDATA;
1249 /* generate scale factors */
1250 for(i = 0; i < n_xbr_ch[chset]; i++) {
1251 const uint32_t *scale_table;
1254 if (s->scalefactor_huffman[chan_base+i] == 6) {
1255 scale_table = ff_dca_scale_factor_quant7;
1257 scale_table = ff_dca_scale_factor_quant6;
1262 for(j = 0; j < active_bands[chset][i]; j++) {
1263 if(abits_high[i][j] > 0) {
1264 scale_table_high[i][j][0] =
1265 scale_table[get_bits(&s->gb, nbits)];
1267 if(xbr_tmode && s->transition_mode[i][j]) {
1268 scale_table_high[i][j][1] =
1269 scale_table[get_bits(&s->gb, nbits)];
1276 /* decode audio array for this block */
1277 for(i = 0; i < n_xbr_ch[chset]; i++) {
1278 for(j = 0; j < active_bands[chset][i]; j++) {
1279 const int xbr_abits = abits_high[i][j];
1280 const float quant_step_size = ff_dca_lossless_quant_d[xbr_abits];
1281 const int sfi = xbr_tmode && s->transition_mode[i][j] && subsubframe >= s->transition_mode[i][j];
1282 const float rscale = quant_step_size * scale_table_high[i][j][sfi];
1283 float *subband_samples = s->subband_samples[k][chan_base+i][j];
1290 get_array(&s->gb, block, 8, xbr_abits - 3);
1292 int block_code1, block_code2, size, levels, err;
1294 size = abits_sizes[xbr_abits - 1];
1295 levels = abits_levels[xbr_abits - 1];
1297 block_code1 = get_bits(&s->gb, size);
1298 block_code2 = get_bits(&s->gb, size);
1299 err = decode_blockcodes(block_code1, block_code2,
1302 av_log(s->avctx, AV_LOG_ERROR,
1303 "ERROR: DTS-XBR: block code look-up failed\n");
1304 return AVERROR_INVALIDDATA;
1308 /* scale & sum into subband */
1309 for(l = 0; l < 8; l++)
1310 subband_samples[l] += (float)block[l] * rscale;
1314 /* check DSYNC marker */
1315 if(s->aspf || subsubframe == s->subsubframes[subframe] - 1) {
1316 if(get_bits(&s->gb, 16) != 0xffff) {
1317 av_log(s->avctx, AV_LOG_ERROR, "DTS-XBR: Didn't get subframe DSYNC\n");
1318 return AVERROR_INVALIDDATA;
1322 /* advance sub-sub-frame index */
1323 if(++subsubframe >= s->subsubframes[subframe]) {
1329 /* skip to next channel set */
1330 i = get_bits_count(&s->gb);
1331 if(start_posn + chset_fsize[chset] * 8 != i) {
1332 j = start_posn + chset_fsize[chset] * 8 - i;
1334 av_log(s->avctx, AV_LOG_ERROR, "DTS-XBR: end of channel set,"
1335 " skipping further than expected (%d bits)\n", j);
1336 skip_bits_long(&s->gb, j);
1344 /* parse initial header for XXCH and dump details */
1345 int ff_dca_xxch_decode_frame(DCAContext *s)
1347 int hdr_size, spkmsk_bits, num_chsets, core_spk, hdr_pos;
1348 int i, chset, base_channel, chstart, fsize[8];
1350 /* assume header word has already been parsed */
1351 hdr_pos = get_bits_count(&s->gb) - 32;
1352 hdr_size = get_bits(&s->gb, 6) + 1;
1353 /*chhdr_crc =*/ skip_bits1(&s->gb);
1354 spkmsk_bits = get_bits(&s->gb, 5) + 1;
1355 num_chsets = get_bits(&s->gb, 2) + 1;
1357 for (i = 0; i < num_chsets; i++)
1358 fsize[i] = get_bits(&s->gb, 14) + 1;
1360 core_spk = get_bits(&s->gb, spkmsk_bits);
1361 s->xxch_core_spkmask = core_spk;
1362 s->xxch_nbits_spk_mask = spkmsk_bits;
1363 s->xxch_dmix_embedded = 0;
1365 /* skip to the end of the header */
1366 i = get_bits_count(&s->gb);
1367 if (hdr_pos + hdr_size * 8 > i)
1368 skip_bits_long(&s->gb, hdr_pos + hdr_size * 8 - i);
1370 for (chset = 0; chset < num_chsets; chset++) {
1371 chstart = get_bits_count(&s->gb);
1372 base_channel = s->prim_channels;
1373 s->xxch_chset = chset;
1375 /* XXCH and Core headers differ, see 6.4.2 "XXCH Channel Set Header" vs.
1376 5.3.2 "Primary Audio Coding Header", DTS Spec 1.3.1 */
1377 dca_parse_audio_coding_header(s, base_channel, 1);
1379 /* decode channel data */
1380 for (i = 0; i < (s->sample_blocks / 8); i++) {
1381 if (dca_decode_block(s, base_channel, i)) {
1382 av_log(s->avctx, AV_LOG_ERROR,
1383 "Error decoding DTS-XXCH extension\n");
1388 /* skip to end of this section */
1389 i = get_bits_count(&s->gb);
1390 if (chstart + fsize[chset] * 8 > i)
1391 skip_bits_long(&s->gb, chstart + fsize[chset] * 8 - i);
1393 s->xxch_chset = num_chsets;
1398 static float dca_dmix_code(unsigned code)
1400 int sign = (code >> 8) - 1;
1402 return ((ff_dca_dmixtable[code] ^ sign) - sign) * (1.0 / (1 << 15));
1406 * Main frame decoding function
1407 * FIXME add arguments
1409 static int dca_decode_frame(AVCodecContext *avctx, void *data,
1410 int *got_frame_ptr, AVPacket *avpkt)
1412 AVFrame *frame = data;
1413 const uint8_t *buf = avpkt->data;
1414 int buf_size = avpkt->size;
1418 int num_core_channels = 0;
1420 float **samples_flt;
1423 DCAContext *s = avctx->priv_data;
1425 int channels, full_channels;
1437 s->dca_buffer_size = avpriv_dca_convert_bitstream(buf, buf_size, s->dca_buffer,
1438 DCA_MAX_FRAME_SIZE + DCA_MAX_EXSS_HEADER_SIZE);
1439 if (s->dca_buffer_size == AVERROR_INVALIDDATA) {
1440 av_log(avctx, AV_LOG_ERROR, "Not a valid DCA frame\n");
1441 return AVERROR_INVALIDDATA;
1444 if ((ret = dca_parse_frame_header(s)) < 0) {
1445 // seems like the frame is corrupt, try with the next one
1448 // set AVCodec values with parsed data
1449 avctx->sample_rate = s->sample_rate;
1450 avctx->bit_rate = s->bit_rate;
1452 s->profile = FF_PROFILE_DTS;
1454 for (i = 0; i < (s->sample_blocks / 8); i++) {
1455 if ((ret = dca_decode_block(s, 0, i))) {
1456 av_log(avctx, AV_LOG_ERROR, "error decoding block\n");
1461 /* record number of core channels incase less than max channels are requested */
1462 num_core_channels = s->prim_channels;
1464 if (s->prim_channels + !!s->lfe > 2 &&
1465 avctx->request_channel_layout == AV_CH_LAYOUT_STEREO) {
1466 /* Stereo downmix coefficients
1468 * The decoder can only downmix to 2-channel, so we need to ensure
1469 * embedded downmix coefficients are actually targeting 2-channel.
1471 if (s->core_downmix && (s->core_downmix_amode == DCA_STEREO ||
1472 s->core_downmix_amode == DCA_STEREO_TOTAL)) {
1473 for (i = 0; i < num_core_channels + !!s->lfe; i++) {
1474 /* Range checked earlier */
1475 s->downmix_coef[i][0] = dca_dmix_code(s->core_downmix_codes[i][0]);
1476 s->downmix_coef[i][1] = dca_dmix_code(s->core_downmix_codes[i][1]);
1478 s->output = s->core_downmix_amode;
1480 int am = s->amode & DCA_CHANNEL_MASK;
1481 if (am >= FF_ARRAY_ELEMS(ff_dca_default_coeffs)) {
1482 av_log(s->avctx, AV_LOG_ERROR,
1483 "Invalid channel mode %d\n", am);
1484 return AVERROR_INVALIDDATA;
1486 if (num_core_channels + !!s->lfe >
1487 FF_ARRAY_ELEMS(ff_dca_default_coeffs[0])) {
1488 avpriv_request_sample(s->avctx, "Downmixing %d channels",
1489 s->prim_channels + !!s->lfe);
1490 return AVERROR_PATCHWELCOME;
1492 for (i = 0; i < num_core_channels + !!s->lfe; i++) {
1493 s->downmix_coef[i][0] = ff_dca_default_coeffs[am][i][0];
1494 s->downmix_coef[i][1] = ff_dca_default_coeffs[am][i][1];
1497 av_dlog(s->avctx, "Stereo downmix coeffs:\n");
1498 for (i = 0; i < num_core_channels + !!s->lfe; i++) {
1499 av_dlog(s->avctx, "L, input channel %d = %f\n", i,
1500 s->downmix_coef[i][0]);
1501 av_dlog(s->avctx, "R, input channel %d = %f\n", i,
1502 s->downmix_coef[i][1]);
1504 av_dlog(s->avctx, "\n");
1508 s->core_ext_mask = dca_ext_audio_descr_mask[s->ext_descr];
1510 s->core_ext_mask = 0;
1512 core_ss_end = FFMIN(s->frame_size, s->dca_buffer_size) * 8;
1514 /* only scan for extensions if ext_descr was unknown or indicated a
1515 * supported XCh extension */
1516 if (s->core_ext_mask < 0 || s->core_ext_mask & (DCA_EXT_XCH | DCA_EXT_XXCH)) {
1517 /* if ext_descr was unknown, clear s->core_ext_mask so that the
1518 * extensions scan can fill it up */
1519 s->core_ext_mask = FFMAX(s->core_ext_mask, 0);
1521 /* extensions start at 32-bit boundaries into bitstream */
1522 skip_bits_long(&s->gb, (-get_bits_count(&s->gb)) & 31);
1524 while (core_ss_end - get_bits_count(&s->gb) >= 32) {
1525 uint32_t bits = get_bits_long(&s->gb, 32);
1529 int ext_amode, xch_fsize;
1531 s->xch_base_channel = s->prim_channels;
1533 /* validate sync word using XCHFSIZE field */
1534 xch_fsize = show_bits(&s->gb, 10);
1535 if ((s->frame_size != (get_bits_count(&s->gb) >> 3) - 4 + xch_fsize) &&
1536 (s->frame_size != (get_bits_count(&s->gb) >> 3) - 4 + xch_fsize + 1))
1539 /* skip length-to-end-of-frame field for the moment */
1540 skip_bits(&s->gb, 10);
1542 s->core_ext_mask |= DCA_EXT_XCH;
1544 /* extension amode(number of channels in extension) should be 1 */
1545 /* AFAIK XCh is not used for more channels */
1546 if ((ext_amode = get_bits(&s->gb, 4)) != 1) {
1547 av_log(avctx, AV_LOG_ERROR,
1548 "XCh extension amode %d not supported!\n",
1553 if (s->xch_base_channel < 2) {
1554 avpriv_request_sample(avctx, "XCh with fewer than 2 base channels");
1558 /* much like core primary audio coding header */
1559 dca_parse_audio_coding_header(s, s->xch_base_channel, 0);
1561 for (i = 0; i < (s->sample_blocks / 8); i++)
1562 if ((ret = dca_decode_block(s, s->xch_base_channel, i))) {
1563 av_log(avctx, AV_LOG_ERROR, "error decoding XCh extension\n");
1571 /* XXCh: extended channels */
1572 /* usually found either in core or HD part in DTS-HD HRA streams,
1573 * but not in DTS-ES which contains XCh extensions instead */
1574 s->core_ext_mask |= DCA_EXT_XXCH;
1575 ff_dca_xxch_decode_frame(s);
1579 int fsize96 = show_bits(&s->gb, 12) + 1;
1580 if (s->frame_size != (get_bits_count(&s->gb) >> 3) - 4 + fsize96)
1583 av_log(avctx, AV_LOG_DEBUG, "X96 extension found at %d bits\n",
1584 get_bits_count(&s->gb));
1585 skip_bits(&s->gb, 12);
1586 av_log(avctx, AV_LOG_DEBUG, "FSIZE96 = %d bytes\n", fsize96);
1587 av_log(avctx, AV_LOG_DEBUG, "REVNO = %d\n", get_bits(&s->gb, 4));
1589 s->core_ext_mask |= DCA_EXT_X96;
1594 skip_bits_long(&s->gb, (-get_bits_count(&s->gb)) & 31);
1597 /* no supported extensions, skip the rest of the core substream */
1598 skip_bits_long(&s->gb, core_ss_end - get_bits_count(&s->gb));
1601 if (s->core_ext_mask & DCA_EXT_X96)
1602 s->profile = FF_PROFILE_DTS_96_24;
1603 else if (s->core_ext_mask & (DCA_EXT_XCH | DCA_EXT_XXCH))
1604 s->profile = FF_PROFILE_DTS_ES;
1606 /* check for ExSS (HD part) */
1607 if (s->dca_buffer_size - s->frame_size > 32 &&
1608 get_bits_long(&s->gb, 32) == DCA_HD_MARKER)
1609 ff_dca_exss_parse_header(s);
1611 avctx->profile = s->profile;
1613 full_channels = channels = s->prim_channels + !!s->lfe;
1615 /* If we have XXCH then the channel layout is managed differently */
1616 /* note that XLL will also have another way to do things */
1617 if (!(s->core_ext_mask & DCA_EXT_XXCH)
1618 || (s->core_ext_mask & DCA_EXT_XXCH && avctx->request_channels > 0
1619 && avctx->request_channels
1620 < num_core_channels + !!s->lfe + s->xxch_chset_nch[0]))
1621 { /* xxx should also do MA extensions */
1622 if (s->amode < 16) {
1623 avctx->channel_layout = dca_core_channel_layout[s->amode];
1625 if (s->prim_channels + !!s->lfe > 2 &&
1626 avctx->request_channel_layout == AV_CH_LAYOUT_STEREO) {
1628 * Neither the core's auxiliary data nor our default tables contain
1629 * downmix coefficients for the additional channel coded in the XCh
1630 * extension, so when we're doing a Stereo downmix, don't decode it.
1635 #if FF_API_REQUEST_CHANNELS
1636 FF_DISABLE_DEPRECATION_WARNINGS
1637 if (s->xch_present && !s->xch_disable &&
1638 (!avctx->request_channels ||
1639 avctx->request_channels > num_core_channels + !!s->lfe)) {
1640 FF_ENABLE_DEPRECATION_WARNINGS
1642 if (s->xch_present && !s->xch_disable) {
1644 if (avctx->channel_layout & AV_CH_BACK_CENTER) {
1645 avpriv_request_sample(avctx, "XCh with Back center channel");
1646 return AVERROR_INVALIDDATA;
1648 avctx->channel_layout |= AV_CH_BACK_CENTER;
1650 avctx->channel_layout |= AV_CH_LOW_FREQUENCY;
1651 s->channel_order_tab = ff_dca_channel_reorder_lfe_xch[s->amode];
1653 s->channel_order_tab = ff_dca_channel_reorder_nolfe_xch[s->amode];
1655 if (s->channel_order_tab[s->xch_base_channel] < 0)
1656 return AVERROR_INVALIDDATA;
1658 channels = num_core_channels + !!s->lfe;
1659 s->xch_present = 0; /* disable further xch processing */
1661 avctx->channel_layout |= AV_CH_LOW_FREQUENCY;
1662 s->channel_order_tab = ff_dca_channel_reorder_lfe[s->amode];
1664 s->channel_order_tab = ff_dca_channel_reorder_nolfe[s->amode];
1667 if (channels > !!s->lfe &&
1668 s->channel_order_tab[channels - 1 - !!s->lfe] < 0)
1669 return AVERROR_INVALIDDATA;
1671 if (av_get_channel_layout_nb_channels(avctx->channel_layout) != channels) {
1672 av_log(avctx, AV_LOG_ERROR, "Number of channels %d mismatches layout %d\n", channels, av_get_channel_layout_nb_channels(avctx->channel_layout));
1673 return AVERROR_INVALIDDATA;
1676 if (num_core_channels + !!s->lfe > 2 &&
1677 avctx->request_channel_layout == AV_CH_LAYOUT_STEREO) {
1679 s->output = s->prim_channels == 2 ? s->amode : DCA_STEREO;
1680 avctx->channel_layout = AV_CH_LAYOUT_STEREO;
1682 else if (avctx->request_channel_layout & AV_CH_LAYOUT_NATIVE) {
1683 static const int8_t dca_channel_order_native[9] = { 0, 1, 2, 3, 4, 5, 6, 7, 8 };
1684 s->channel_order_tab = dca_channel_order_native;
1686 s->lfe_index = ff_dca_lfe_index[s->amode];
1688 av_log(avctx, AV_LOG_ERROR,
1689 "Non standard configuration %d !\n", s->amode);
1690 return AVERROR_INVALIDDATA;
1693 s->xxch_dmix_embedded = 0;
1695 /* we only get here if an XXCH channel set can be added to the mix */
1696 channel_mask = s->xxch_core_spkmask;
1698 if (avctx->request_channels > 0
1699 && avctx->request_channels < s->prim_channels) {
1700 channels = num_core_channels + !!s->lfe;
1701 for (i = 0; i < s->xxch_chset && channels + s->xxch_chset_nch[i]
1702 <= avctx->request_channels; i++) {
1703 channels += s->xxch_chset_nch[i];
1704 channel_mask |= s->xxch_spk_masks[i];
1707 channels = s->prim_channels + !!s->lfe;
1708 for (i = 0; i < s->xxch_chset; i++) {
1709 channel_mask |= s->xxch_spk_masks[i];
1713 /* Given the DTS spec'ed channel mask, generate an avcodec version */
1715 for (i = 0; i < s->xxch_nbits_spk_mask; ++i) {
1716 if (channel_mask & (1 << i)) {
1717 channel_layout |= map_xxch_to_native[i];
1721 /* make sure that we have managed to get equivalent dts/avcodec channel
1722 * masks in some sense -- unfortunately some channels could overlap */
1723 if (av_popcount(channel_mask) != av_popcount(channel_layout)) {
1724 av_log(avctx, AV_LOG_DEBUG,
1725 "DTS-XXCH: Inconsistent avcodec/dts channel layouts\n");
1726 return AVERROR_INVALIDDATA;
1729 avctx->channel_layout = channel_layout;
1731 if (!(avctx->request_channel_layout & AV_CH_LAYOUT_NATIVE)) {
1732 /* Estimate DTS --> avcodec ordering table */
1733 for (chset = -1, j = 0; chset < s->xxch_chset; ++chset) {
1734 mask = chset >= 0 ? s->xxch_spk_masks[chset]
1735 : s->xxch_core_spkmask;
1736 for (i = 0; i < s->xxch_nbits_spk_mask; i++) {
1737 if (mask & ~(DCA_XXCH_LFE1 | DCA_XXCH_LFE2) & (1 << i)) {
1738 lavc = map_xxch_to_native[i];
1739 posn = av_popcount(channel_layout & (lavc - 1));
1740 s->xxch_order_tab[j++] = posn;
1746 s->lfe_index = av_popcount(channel_layout & (AV_CH_LOW_FREQUENCY-1));
1747 } else { /* native ordering */
1748 for (i = 0; i < channels; i++)
1749 s->xxch_order_tab[i] = i;
1751 s->lfe_index = channels - 1;
1754 s->channel_order_tab = s->xxch_order_tab;
1757 if (avctx->channels != channels) {
1758 if (avctx->channels)
1759 av_log(avctx, AV_LOG_INFO, "Number of channels changed in DCA decoder (%d -> %d)\n", avctx->channels, channels);
1760 avctx->channels = channels;
1763 /* get output buffer */
1764 frame->nb_samples = 256 * (s->sample_blocks / 8);
1765 if ((ret = ff_get_buffer(avctx, frame, 0)) < 0)
1767 samples_flt = (float **) frame->extended_data;
1769 /* allocate buffer for extra channels if downmixing */
1770 if (avctx->channels < full_channels) {
1771 ret = av_samples_get_buffer_size(NULL, full_channels - channels,
1773 avctx->sample_fmt, 0);
1777 av_fast_malloc(&s->extra_channels_buffer,
1778 &s->extra_channels_buffer_size, ret);
1779 if (!s->extra_channels_buffer)
1780 return AVERROR(ENOMEM);
1782 ret = av_samples_fill_arrays((uint8_t **) s->extra_channels, NULL,
1783 s->extra_channels_buffer,
1784 full_channels - channels,
1785 frame->nb_samples, avctx->sample_fmt, 0);
1790 /* filter to get final output */
1791 for (i = 0; i < (s->sample_blocks / 8); i++) {
1794 for (ch = 0; ch < channels; ch++)
1795 s->samples_chanptr[ch] = samples_flt[ch] + i * 256;
1796 for (; ch < full_channels; ch++)
1797 s->samples_chanptr[ch] = s->extra_channels[ch - channels] + i * 256;
1799 dca_filter_channels(s, i);
1801 /* If this was marked as a DTS-ES stream we need to subtract back- */
1802 /* channel from SL & SR to remove matrixed back-channel signal */
1803 if ((s->source_pcm_res & 1) && s->xch_present) {
1804 float *back_chan = s->samples_chanptr[s->channel_order_tab[s->xch_base_channel]];
1805 float *lt_chan = s->samples_chanptr[s->channel_order_tab[s->xch_base_channel - 2]];
1806 float *rt_chan = s->samples_chanptr[s->channel_order_tab[s->xch_base_channel - 1]];
1807 s->fdsp->vector_fmac_scalar(lt_chan, back_chan, -M_SQRT1_2, 256);
1808 s->fdsp->vector_fmac_scalar(rt_chan, back_chan, -M_SQRT1_2, 256);
1811 /* If stream contains XXCH, we might need to undo an embedded downmix */
1812 if (s->xxch_dmix_embedded) {
1813 /* Loop over channel sets in turn */
1814 ch = num_core_channels;
1815 for (chset = 0; chset < s->xxch_chset; chset++) {
1816 endch = ch + s->xxch_chset_nch[chset];
1817 mask = s->xxch_dmix_embedded;
1820 for (j = ch; j < endch; j++) {
1821 if (mask & (1 << j)) { /* this channel has been mixed-out */
1822 src_chan = s->samples_chanptr[s->channel_order_tab[j]];
1823 for (k = 0; k < endch; k++) {
1824 achan = s->channel_order_tab[k];
1825 scale = s->xxch_dmix_coeff[j][k];
1827 dst_chan = s->samples_chanptr[achan];
1828 s->fdsp->vector_fmac_scalar(dst_chan, src_chan,
1835 /* if a downmix has been embedded then undo the pre-scaling */
1836 if ((mask & (1 << ch)) && s->xxch_dmix_sf[chset] != 1.0f) {
1837 scale = s->xxch_dmix_sf[chset];
1839 for (j = 0; j < ch; j++) {
1840 src_chan = s->samples_chanptr[s->channel_order_tab[j]];
1841 for (k = 0; k < 256; k++)
1842 src_chan[k] *= scale;
1845 /* LFE channel is always part of core, scale if it exists */
1847 src_chan = s->samples_chanptr[s->lfe_index];
1848 for (k = 0; k < 256; k++)
1849 src_chan[k] *= scale;
1859 /* update lfe history */
1860 lfe_samples = 2 * s->lfe * (s->sample_blocks / 8);
1861 for (i = 0; i < 2 * s->lfe * 4; i++)
1862 s->lfe_data[i] = s->lfe_data[i + lfe_samples];
1866 * DCA_STEREO_TOTAL (Lt/Rt) is equivalent to Dolby Surround */
1867 ret = ff_side_data_update_matrix_encoding(frame,
1868 (s->output & ~DCA_LFE) == DCA_STEREO_TOTAL ?
1869 AV_MATRIX_ENCODING_DOLBY : AV_MATRIX_ENCODING_NONE);
1879 * DCA initialization
1881 * @param avctx pointer to the AVCodecContext
1884 static av_cold int dca_decode_init(AVCodecContext *avctx)
1886 DCAContext *s = avctx->priv_data;
1891 s->fdsp = avpriv_float_dsp_alloc(avctx->flags & CODEC_FLAG_BITEXACT);
1893 return AVERROR(ENOMEM);
1895 ff_mdct_init(&s->imdct, 6, 1, 1.0);
1896 ff_synth_filter_init(&s->synth);
1897 ff_dcadsp_init(&s->dcadsp);
1898 ff_fmt_convert_init(&s->fmt_conv, avctx);
1900 avctx->sample_fmt = AV_SAMPLE_FMT_FLTP;
1902 /* allow downmixing to stereo */
1903 #if FF_API_REQUEST_CHANNELS
1904 FF_DISABLE_DEPRECATION_WARNINGS
1905 if (avctx->request_channels == 2)
1906 avctx->request_channel_layout = AV_CH_LAYOUT_STEREO;
1907 FF_ENABLE_DEPRECATION_WARNINGS
1909 if (avctx->channels > 2 &&
1910 avctx->request_channel_layout == AV_CH_LAYOUT_STEREO)
1911 avctx->channels = 2;
1916 static av_cold int dca_decode_end(AVCodecContext *avctx)
1918 DCAContext *s = avctx->priv_data;
1919 ff_mdct_end(&s->imdct);
1920 av_freep(&s->extra_channels_buffer);
1925 static const AVProfile profiles[] = {
1926 { FF_PROFILE_DTS, "DTS" },
1927 { FF_PROFILE_DTS_ES, "DTS-ES" },
1928 { FF_PROFILE_DTS_96_24, "DTS 96/24" },
1929 { FF_PROFILE_DTS_HD_HRA, "DTS-HD HRA" },
1930 { FF_PROFILE_DTS_HD_MA, "DTS-HD MA" },
1931 { FF_PROFILE_UNKNOWN },
1934 static const AVOption options[] = {
1935 { "disable_xch", "disable decoding of the XCh extension", offsetof(DCAContext, xch_disable), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, 1, AV_OPT_FLAG_DECODING_PARAM | AV_OPT_FLAG_AUDIO_PARAM },
1939 static const AVClass dca_decoder_class = {
1940 .class_name = "DCA decoder",
1941 .item_name = av_default_item_name,
1943 .version = LIBAVUTIL_VERSION_INT,
1944 .category = AV_CLASS_CATEGORY_DECODER,
1947 AVCodec ff_dca_decoder = {
1949 .long_name = NULL_IF_CONFIG_SMALL("DCA (DTS Coherent Acoustics)"),
1950 .type = AVMEDIA_TYPE_AUDIO,
1951 .id = AV_CODEC_ID_DTS,
1952 .priv_data_size = sizeof(DCAContext),
1953 .init = dca_decode_init,
1954 .decode = dca_decode_frame,
1955 .close = dca_decode_end,
1956 .capabilities = CODEC_CAP_CHANNEL_CONF | CODEC_CAP_DR1,
1957 .sample_fmts = (const enum AVSampleFormat[]) { AV_SAMPLE_FMT_FLTP,
1958 AV_SAMPLE_FMT_NONE },
1959 .profiles = NULL_IF_CONFIG_SMALL(profiles),
1960 .priv_class = &dca_decoder_class,