1 /*
2 * MPEG-4 ALS decoder
3 * Copyright (c) 2009 Thilo Borgmann <thilo.borgmann _at_ mail.de>
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-4 ALS decoder
25 * @author Thilo Borgmann <thilo.borgmann _at_ mail.de>
26 */
27
28 #include <inttypes.h>
29
30 #include "avcodec.h"
31 #include "get_bits.h"
32 #include "unary.h"
33 #include "mpeg4audio.h"
34 #include "bgmc.h"
35 #include "bswapdsp.h"
36 #include "codec_internal.h"
37 #include "internal.h"
38 #include "mlz.h"
39 #include "libavutil/samplefmt.h"
40 #include "libavutil/crc.h"
41 #include "libavutil/softfloat_ieee754.h"
42 #include "libavutil/intfloat.h"
43 #include "libavutil/intreadwrite.h"
44
45 #include <stdint.h>
46
47 /** Rice parameters and corresponding index offsets for decoding the
48 * indices of scaled PARCOR values. The table chosen is set globally
49 * by the encoder and stored in ALSSpecificConfig.
50 */
51 static const int8_t parcor_rice_table[3][20][2] = {
52 { {-52, 4}, {-29, 5}, {-31, 4}, { 19, 4}, {-16, 4},
53 { 12, 3}, { -7, 3}, { 9, 3}, { -5, 3}, { 6, 3},
54 { -4, 3}, { 3, 3}, { -3, 2}, { 3, 2}, { -2, 2},
55 { 3, 2}, { -1, 2}, { 2, 2}, { -1, 2}, { 2, 2} },
56 { {-58, 3}, {-42, 4}, {-46, 4}, { 37, 5}, {-36, 4},
57 { 29, 4}, {-29, 4}, { 25, 4}, {-23, 4}, { 20, 4},
58 {-17, 4}, { 16, 4}, {-12, 4}, { 12, 3}, {-10, 4},
59 { 7, 3}, { -4, 4}, { 3, 3}, { -1, 3}, { 1, 3} },
60 { {-59, 3}, {-45, 5}, {-50, 4}, { 38, 4}, {-39, 4},
61 { 32, 4}, {-30, 4}, { 25, 3}, {-23, 3}, { 20, 3},
62 {-20, 3}, { 16, 3}, {-13, 3}, { 10, 3}, { -7, 3},
63 { 3, 3}, { 0, 3}, { -1, 3}, { 2, 3}, { -1, 2} }
64 };
65
66
67 /** Scaled PARCOR values used for the first two PARCOR coefficients.
68 * To be indexed by the Rice coded indices.
69 * Generated by: parcor_scaled_values[i] = 32 + ((i * (i+1)) << 7) - (1 << 20)
70 * Actual values are divided by 32 in order to be stored in 16 bits.
71 */
72 static const int16_t parcor_scaled_values[] = {
73 -1048544 / 32, -1048288 / 32, -1047776 / 32, -1047008 / 32,
74 -1045984 / 32, -1044704 / 32, -1043168 / 32, -1041376 / 32,
75 -1039328 / 32, -1037024 / 32, -1034464 / 32, -1031648 / 32,
76 -1028576 / 32, -1025248 / 32, -1021664 / 32, -1017824 / 32,
77 -1013728 / 32, -1009376 / 32, -1004768 / 32, -999904 / 32,
78 -994784 / 32, -989408 / 32, -983776 / 32, -977888 / 32,
79 -971744 / 32, -965344 / 32, -958688 / 32, -951776 / 32,
80 -944608 / 32, -937184 / 32, -929504 / 32, -921568 / 32,
81 -913376 / 32, -904928 / 32, -896224 / 32, -887264 / 32,
82 -878048 / 32, -868576 / 32, -858848 / 32, -848864 / 32,
83 -838624 / 32, -828128 / 32, -817376 / 32, -806368 / 32,
84 -795104 / 32, -783584 / 32, -771808 / 32, -759776 / 32,
85 -747488 / 32, -734944 / 32, -722144 / 32, -709088 / 32,
86 -695776 / 32, -682208 / 32, -668384 / 32, -654304 / 32,
87 -639968 / 32, -625376 / 32, -610528 / 32, -595424 / 32,
88 -580064 / 32, -564448 / 32, -548576 / 32, -532448 / 32,
89 -516064 / 32, -499424 / 32, -482528 / 32, -465376 / 32,
90 -447968 / 32, -430304 / 32, -412384 / 32, -394208 / 32,
91 -375776 / 32, -357088 / 32, -338144 / 32, -318944 / 32,
92 -299488 / 32, -279776 / 32, -259808 / 32, -239584 / 32,
93 -219104 / 32, -198368 / 32, -177376 / 32, -156128 / 32,
94 -134624 / 32, -112864 / 32, -90848 / 32, -68576 / 32,
95 -46048 / 32, -23264 / 32, -224 / 32, 23072 / 32,
96 46624 / 32, 70432 / 32, 94496 / 32, 118816 / 32,
97 143392 / 32, 168224 / 32, 193312 / 32, 218656 / 32,
98 244256 / 32, 270112 / 32, 296224 / 32, 322592 / 32,
99 349216 / 32, 376096 / 32, 403232 / 32, 430624 / 32,
100 458272 / 32, 486176 / 32, 514336 / 32, 542752 / 32,
101 571424 / 32, 600352 / 32, 629536 / 32, 658976 / 32,
102 688672 / 32, 718624 / 32, 748832 / 32, 779296 / 32,
103 810016 / 32, 840992 / 32, 872224 / 32, 903712 / 32,
104 935456 / 32, 967456 / 32, 999712 / 32, 1032224 / 32
105 };
106
107
108 /** Gain values of p(0) for long-term prediction.
109 * To be indexed by the Rice coded indices.
110 */
111 static const uint8_t ltp_gain_values [4][4] = {
112 { 0, 8, 16, 24},
113 {32, 40, 48, 56},
114 {64, 70, 76, 82},
115 {88, 92, 96, 100}
116 };
117
118
119 /** Inter-channel weighting factors for multi-channel correlation.
120 * To be indexed by the Rice coded indices.
121 */
122 static const int16_t mcc_weightings[] = {
123 204, 192, 179, 166, 153, 140, 128, 115,
124 102, 89, 76, 64, 51, 38, 25, 12,
125 0, -12, -25, -38, -51, -64, -76, -89,
126 -102, -115, -128, -140, -153, -166, -179, -192
127 };
128
129
130 /** Tail codes used in arithmetic coding using block Gilbert-Moore codes.
131 */
132 static const uint8_t tail_code[16][6] = {
133 { 74, 44, 25, 13, 7, 3},
134 { 68, 42, 24, 13, 7, 3},
135 { 58, 39, 23, 13, 7, 3},
136 {126, 70, 37, 19, 10, 5},
137 {132, 70, 37, 20, 10, 5},
138 {124, 70, 38, 20, 10, 5},
139 {120, 69, 37, 20, 11, 5},
140 {116, 67, 37, 20, 11, 5},
141 {108, 66, 36, 20, 10, 5},
142 {102, 62, 36, 20, 10, 5},
143 { 88, 58, 34, 19, 10, 5},
144 {162, 89, 49, 25, 13, 7},
145 {156, 87, 49, 26, 14, 7},
146 {150, 86, 47, 26, 14, 7},
147 {142, 84, 47, 26, 14, 7},
148 {131, 79, 46, 26, 14, 7}
149 };
150
151
152 enum RA_Flag {
153 RA_FLAG_NONE,
154 RA_FLAG_FRAMES,
155 RA_FLAG_HEADER
156 };
157
158
159 typedef struct ALSSpecificConfig {
160 uint32_t samples; ///< number of samples, 0xFFFFFFFF if unknown
161 int resolution; ///< 000 = 8-bit; 001 = 16-bit; 010 = 24-bit; 011 = 32-bit
162 int floating; ///< 1 = IEEE 32-bit floating-point, 0 = integer
163 int msb_first; ///< 1 = original CRC calculated on big-endian system, 0 = little-endian
164 int frame_length; ///< frame length for each frame (last frame may differ)
165 int ra_distance; ///< distance between RA frames (in frames, 0...255)
166 enum RA_Flag ra_flag; ///< indicates where the size of ra units is stored
167 int adapt_order; ///< adaptive order: 1 = on, 0 = off
168 int coef_table; ///< table index of Rice code parameters
169 int long_term_prediction; ///< long term prediction (LTP): 1 = on, 0 = off
170 int max_order; ///< maximum prediction order (0..1023)
171 int block_switching; ///< number of block switching levels
172 int bgmc; ///< "Block Gilbert-Moore Code": 1 = on, 0 = off (Rice coding only)
173 int sb_part; ///< sub-block partition
174 int joint_stereo; ///< joint stereo: 1 = on, 0 = off
175 int mc_coding; ///< extended inter-channel coding (multi channel coding): 1 = on, 0 = off
176 int chan_config; ///< indicates that a chan_config_info field is present
177 int chan_sort; ///< channel rearrangement: 1 = on, 0 = off
178 int rlslms; ///< use "Recursive Least Square-Least Mean Square" predictor: 1 = on, 0 = off
179 int chan_config_info; ///< mapping of channels to loudspeaker locations. Unused until setting channel configuration is implemented.
180 int *chan_pos; ///< original channel positions
181 int crc_enabled; ///< enable Cyclic Redundancy Checksum
182 } ALSSpecificConfig;
183
184
185 typedef struct ALSChannelData {
186 int stop_flag;
187 int master_channel;
188 int time_diff_flag;
189 int time_diff_sign;
190 int time_diff_index;
191 int weighting[6];
192 } ALSChannelData;
193
194
195 typedef struct ALSDecContext {
196 AVCodecContext *avctx;
197 ALSSpecificConfig sconf;
198 GetBitContext gb;
199 BswapDSPContext bdsp;
200 const AVCRC *crc_table;
201 uint32_t crc_org; ///< CRC value of the original input data
202 uint32_t crc; ///< CRC value calculated from decoded data
203 unsigned int cur_frame_length; ///< length of the current frame to decode
204 unsigned int frame_id; ///< the frame ID / number of the current frame
205 unsigned int js_switch; ///< if true, joint-stereo decoding is enforced
206 unsigned int cs_switch; ///< if true, channel rearrangement is done
207 unsigned int num_blocks; ///< number of blocks used in the current frame
208 unsigned int s_max; ///< maximum Rice parameter allowed in entropy coding
209 uint8_t *bgmc_lut; ///< pointer at lookup tables used for BGMC
210 int *bgmc_lut_status; ///< pointer at lookup table status flags used for BGMC
211 int ltp_lag_length; ///< number of bits used for ltp lag value
212 int *const_block; ///< contains const_block flags for all channels
213 unsigned int *shift_lsbs; ///< contains shift_lsbs flags for all channels
214 unsigned int *opt_order; ///< contains opt_order flags for all channels
215 int *store_prev_samples; ///< contains store_prev_samples flags for all channels
216 int *use_ltp; ///< contains use_ltp flags for all channels
217 int *ltp_lag; ///< contains ltp lag values for all channels
218 int **ltp_gain; ///< gain values for ltp 5-tap filter for a channel
219 int *ltp_gain_buffer; ///< contains all gain values for ltp 5-tap filter
220 int32_t **quant_cof; ///< quantized parcor coefficients for a channel
221 int32_t *quant_cof_buffer; ///< contains all quantized parcor coefficients
222 int32_t **lpc_cof; ///< coefficients of the direct form prediction filter for a channel
223 int32_t *lpc_cof_buffer; ///< contains all coefficients of the direct form prediction filter
224 int32_t *lpc_cof_reversed_buffer; ///< temporary buffer to set up a reversed versio of lpc_cof_buffer
225 ALSChannelData **chan_data; ///< channel data for multi-channel correlation
226 ALSChannelData *chan_data_buffer; ///< contains channel data for all channels
227 int *reverted_channels; ///< stores a flag for each reverted channel
228 int32_t *prev_raw_samples; ///< contains unshifted raw samples from the previous block
229 int32_t **raw_samples; ///< decoded raw samples for each channel
230 int32_t *raw_buffer; ///< contains all decoded raw samples including carryover samples
231 uint8_t *crc_buffer; ///< buffer of byte order corrected samples used for CRC check
232 MLZ* mlz; ///< masked lz decompression structure
233 SoftFloat_IEEE754 *acf; ///< contains common multiplier for all channels
234 int *last_acf_mantissa; ///< contains the last acf mantissa data of common multiplier for all channels
235 int *shift_value; ///< value by which the binary point is to be shifted for all channels
236 int *last_shift_value; ///< contains last shift value for all channels
237 int **raw_mantissa; ///< decoded mantissa bits of the difference signal
238 unsigned char *larray; ///< buffer to store the output of masked lz decompression
239 int *nbits; ///< contains the number of bits to read for masked lz decompression for all samples
240 int highest_decoded_channel;
241 } ALSDecContext;
242
243
244 typedef struct ALSBlockData {
245 unsigned int block_length; ///< number of samples within the block
246 unsigned int ra_block; ///< if true, this is a random access block
247 int *const_block; ///< if true, this is a constant value block
248 int js_blocks; ///< true if this block contains a difference signal
249 unsigned int *shift_lsbs; ///< shift of values for this block
250 unsigned int *opt_order; ///< prediction order of this block
251 int *store_prev_samples;///< if true, carryover samples have to be stored
252 int *use_ltp; ///< if true, long-term prediction is used
253 int *ltp_lag; ///< lag value for long-term prediction
254 int *ltp_gain; ///< gain values for ltp 5-tap filter
255 int32_t *quant_cof; ///< quantized parcor coefficients
256 int32_t *lpc_cof; ///< coefficients of the direct form prediction
257 int32_t *raw_samples; ///< decoded raw samples / residuals for this block
258 int32_t *prev_raw_samples; ///< contains unshifted raw samples from the previous block
259 int32_t *raw_other; ///< decoded raw samples of the other channel of a channel pair
260 } ALSBlockData;
261
262
dprint_specific_config(ALSDecContext * ctx)263 static av_cold void dprint_specific_config(ALSDecContext *ctx)
264 {
265 #ifdef DEBUG
266 AVCodecContext *avctx = ctx->avctx;
267 ALSSpecificConfig *sconf = &ctx->sconf;
268
269 ff_dlog(avctx, "resolution = %i\n", sconf->resolution);
270 ff_dlog(avctx, "floating = %i\n", sconf->floating);
271 ff_dlog(avctx, "frame_length = %i\n", sconf->frame_length);
272 ff_dlog(avctx, "ra_distance = %i\n", sconf->ra_distance);
273 ff_dlog(avctx, "ra_flag = %i\n", sconf->ra_flag);
274 ff_dlog(avctx, "adapt_order = %i\n", sconf->adapt_order);
275 ff_dlog(avctx, "coef_table = %i\n", sconf->coef_table);
276 ff_dlog(avctx, "long_term_prediction = %i\n", sconf->long_term_prediction);
277 ff_dlog(avctx, "max_order = %i\n", sconf->max_order);
278 ff_dlog(avctx, "block_switching = %i\n", sconf->block_switching);
279 ff_dlog(avctx, "bgmc = %i\n", sconf->bgmc);
280 ff_dlog(avctx, "sb_part = %i\n", sconf->sb_part);
281 ff_dlog(avctx, "joint_stereo = %i\n", sconf->joint_stereo);
282 ff_dlog(avctx, "mc_coding = %i\n", sconf->mc_coding);
283 ff_dlog(avctx, "chan_config = %i\n", sconf->chan_config);
284 ff_dlog(avctx, "chan_sort = %i\n", sconf->chan_sort);
285 ff_dlog(avctx, "RLSLMS = %i\n", sconf->rlslms);
286 ff_dlog(avctx, "chan_config_info = %i\n", sconf->chan_config_info);
287 #endif
288 }
289
290
291 /** Read an ALSSpecificConfig from a buffer into the output struct.
292 */
read_specific_config(ALSDecContext * ctx)293 static av_cold int read_specific_config(ALSDecContext *ctx)
294 {
295 GetBitContext gb;
296 uint64_t ht_size;
297 int i, config_offset;
298 MPEG4AudioConfig m4ac = {0};
299 ALSSpecificConfig *sconf = &ctx->sconf;
300 AVCodecContext *avctx = ctx->avctx;
301 uint32_t als_id, header_size, trailer_size;
302 int ret;
303
304 if ((ret = init_get_bits8(&gb, avctx->extradata, avctx->extradata_size)) < 0)
305 return ret;
306
307 config_offset = avpriv_mpeg4audio_get_config2(&m4ac, avctx->extradata,
308 avctx->extradata_size, 1, avctx);
309
310 if (config_offset < 0)
311 return AVERROR_INVALIDDATA;
312
313 skip_bits_long(&gb, config_offset);
314
315 if (get_bits_left(&gb) < (30 << 3))
316 return AVERROR_INVALIDDATA;
317
318 // read the fixed items
319 als_id = get_bits_long(&gb, 32);
320 avctx->sample_rate = m4ac.sample_rate;
321 skip_bits_long(&gb, 32); // sample rate already known
322 sconf->samples = get_bits_long(&gb, 32);
323
324 if (avctx->ch_layout.nb_channels != m4ac.channels) {
325 av_channel_layout_uninit(&avctx->ch_layout);
326 avctx->ch_layout.order = AV_CHANNEL_ORDER_UNSPEC;
327 avctx->ch_layout.nb_channels = m4ac.channels;
328 }
329
330 skip_bits(&gb, 16); // number of channels already known
331 skip_bits(&gb, 3); // skip file_type
332 sconf->resolution = get_bits(&gb, 3);
333 sconf->floating = get_bits1(&gb);
334 sconf->msb_first = get_bits1(&gb);
335 sconf->frame_length = get_bits(&gb, 16) + 1;
336 sconf->ra_distance = get_bits(&gb, 8);
337 sconf->ra_flag = get_bits(&gb, 2);
338 sconf->adapt_order = get_bits1(&gb);
339 sconf->coef_table = get_bits(&gb, 2);
340 sconf->long_term_prediction = get_bits1(&gb);
341 sconf->max_order = get_bits(&gb, 10);
342 sconf->block_switching = get_bits(&gb, 2);
343 sconf->bgmc = get_bits1(&gb);
344 sconf->sb_part = get_bits1(&gb);
345 sconf->joint_stereo = get_bits1(&gb);
346 sconf->mc_coding = get_bits1(&gb);
347 sconf->chan_config = get_bits1(&gb);
348 sconf->chan_sort = get_bits1(&gb);
349 sconf->crc_enabled = get_bits1(&gb);
350 sconf->rlslms = get_bits1(&gb);
351 skip_bits(&gb, 5); // skip 5 reserved bits
352 skip_bits1(&gb); // skip aux_data_enabled
353
354
355 // check for ALSSpecificConfig struct
356 if (als_id != MKBETAG('A','L','S','\0'))
357 return AVERROR_INVALIDDATA;
358
359 if (avctx->ch_layout.nb_channels > FF_SANE_NB_CHANNELS) {
360 avpriv_request_sample(avctx, "Huge number of channels");
361 return AVERROR_PATCHWELCOME;
362 }
363
364 if (avctx->ch_layout.nb_channels == 0)
365 return AVERROR_INVALIDDATA;
366
367 ctx->cur_frame_length = sconf->frame_length;
368
369 // read channel config
370 if (sconf->chan_config)
371 sconf->chan_config_info = get_bits(&gb, 16);
372 // TODO: use this to set avctx->channel_layout
373
374
375 // read channel sorting
376 if (sconf->chan_sort && avctx->ch_layout.nb_channels > 1) {
377 int chan_pos_bits = av_ceil_log2(avctx->ch_layout.nb_channels);
378 int bits_needed = avctx->ch_layout.nb_channels * chan_pos_bits + 7;
379 if (get_bits_left(&gb) < bits_needed)
380 return AVERROR_INVALIDDATA;
381
382 if (!(sconf->chan_pos = av_malloc_array(avctx->ch_layout.nb_channels, sizeof(*sconf->chan_pos))))
383 return AVERROR(ENOMEM);
384
385 ctx->cs_switch = 1;
386
387 for (i = 0; i < avctx->ch_layout.nb_channels; i++) {
388 sconf->chan_pos[i] = -1;
389 }
390
391 for (i = 0; i < avctx->ch_layout.nb_channels; i++) {
392 int idx;
393
394 idx = get_bits(&gb, chan_pos_bits);
395 if (idx >= avctx->ch_layout.nb_channels || sconf->chan_pos[idx] != -1) {
396 av_log(avctx, AV_LOG_WARNING, "Invalid channel reordering.\n");
397 ctx->cs_switch = 0;
398 break;
399 }
400 sconf->chan_pos[idx] = i;
401 }
402
403 align_get_bits(&gb);
404 }
405
406
407 // read fixed header and trailer sizes,
408 // if size = 0xFFFFFFFF then there is no data field!
409 if (get_bits_left(&gb) < 64)
410 return AVERROR_INVALIDDATA;
411
412 header_size = get_bits_long(&gb, 32);
413 trailer_size = get_bits_long(&gb, 32);
414 if (header_size == 0xFFFFFFFF)
415 header_size = 0;
416 if (trailer_size == 0xFFFFFFFF)
417 trailer_size = 0;
418
419 ht_size = ((int64_t)(header_size) + (int64_t)(trailer_size)) << 3;
420
421
422 // skip the header and trailer data
423 if (get_bits_left(&gb) < ht_size)
424 return AVERROR_INVALIDDATA;
425
426 if (ht_size > INT32_MAX)
427 return AVERROR_PATCHWELCOME;
428
429 skip_bits_long(&gb, ht_size);
430
431
432 // initialize CRC calculation
433 if (sconf->crc_enabled) {
434 if (get_bits_left(&gb) < 32)
435 return AVERROR_INVALIDDATA;
436
437 if (avctx->err_recognition & (AV_EF_CRCCHECK|AV_EF_CAREFUL)) {
438 ctx->crc_table = av_crc_get_table(AV_CRC_32_IEEE_LE);
439 ctx->crc = 0xFFFFFFFF;
440 ctx->crc_org = ~get_bits_long(&gb, 32);
441 } else
442 skip_bits_long(&gb, 32);
443 }
444
445
446 // no need to read the rest of ALSSpecificConfig (ra_unit_size & aux data)
447
448 dprint_specific_config(ctx);
449
450 return 0;
451 }
452
453
454 /** Check the ALSSpecificConfig for unsupported features.
455 */
check_specific_config(ALSDecContext * ctx)456 static int check_specific_config(ALSDecContext *ctx)
457 {
458 ALSSpecificConfig *sconf = &ctx->sconf;
459 int error = 0;
460
461 // report unsupported feature and set error value
462 #define MISSING_ERR(cond, str, errval) \
463 { \
464 if (cond) { \
465 avpriv_report_missing_feature(ctx->avctx, \
466 str); \
467 error = errval; \
468 } \
469 }
470
471 MISSING_ERR(sconf->rlslms, "Adaptive RLS-LMS prediction", AVERROR_PATCHWELCOME);
472
473 return error;
474 }
475
476
477 /** Parse the bs_info field to extract the block partitioning used in
478 * block switching mode, refer to ISO/IEC 14496-3, section 11.6.2.
479 */
parse_bs_info(const uint32_t bs_info,unsigned int n,unsigned int div,unsigned int ** div_blocks,unsigned int * num_blocks)480 static void parse_bs_info(const uint32_t bs_info, unsigned int n,
481 unsigned int div, unsigned int **div_blocks,
482 unsigned int *num_blocks)
483 {
484 if (n < 31 && ((bs_info << n) & 0x40000000)) {
485 // if the level is valid and the investigated bit n is set
486 // then recursively check both children at bits (2n+1) and (2n+2)
487 n *= 2;
488 div += 1;
489 parse_bs_info(bs_info, n + 1, div, div_blocks, num_blocks);
490 parse_bs_info(bs_info, n + 2, div, div_blocks, num_blocks);
491 } else {
492 // else the bit is not set or the last level has been reached
493 // (bit implicitly not set)
494 **div_blocks = div;
495 (*div_blocks)++;
496 (*num_blocks)++;
497 }
498 }
499
500
501 /** Read and decode a Rice codeword.
502 */
decode_rice(GetBitContext * gb,unsigned int k)503 static int32_t decode_rice(GetBitContext *gb, unsigned int k)
504 {
505 int max = get_bits_left(gb) - k;
506 unsigned q = get_unary(gb, 0, max);
507 int r = k ? get_bits1(gb) : !(q & 1);
508
509 if (k > 1) {
510 q <<= (k - 1);
511 q += get_bits_long(gb, k - 1);
512 } else if (!k) {
513 q >>= 1;
514 }
515 return r ? q : ~q;
516 }
517
518
519 /** Convert PARCOR coefficient k to direct filter coefficient.
520 */
parcor_to_lpc(unsigned int k,const int32_t * par,int32_t * cof)521 static void parcor_to_lpc(unsigned int k, const int32_t *par, int32_t *cof)
522 {
523 int i, j;
524
525 for (i = 0, j = k - 1; i < j; i++, j--) {
526 unsigned tmp1 = ((MUL64(par[k], cof[j]) + (1 << 19)) >> 20);
527 cof[j] += ((MUL64(par[k], cof[i]) + (1 << 19)) >> 20);
528 cof[i] += tmp1;
529 }
530 if (i == j)
531 cof[i] += ((MUL64(par[k], cof[j]) + (1 << 19)) >> 20);
532
533 cof[k] = par[k];
534 }
535
536
537 /** Read block switching field if necessary and set actual block sizes.
538 * Also assure that the block sizes of the last frame correspond to the
539 * actual number of samples.
540 */
get_block_sizes(ALSDecContext * ctx,unsigned int * div_blocks,uint32_t * bs_info)541 static void get_block_sizes(ALSDecContext *ctx, unsigned int *div_blocks,
542 uint32_t *bs_info)
543 {
544 ALSSpecificConfig *sconf = &ctx->sconf;
545 GetBitContext *gb = &ctx->gb;
546 unsigned int *ptr_div_blocks = div_blocks;
547 unsigned int b;
548
549 if (sconf->block_switching) {
550 unsigned int bs_info_len = 1 << (sconf->block_switching + 2);
551 *bs_info = get_bits_long(gb, bs_info_len);
552 *bs_info <<= (32 - bs_info_len);
553 }
554
555 ctx->num_blocks = 0;
556 parse_bs_info(*bs_info, 0, 0, &ptr_div_blocks, &ctx->num_blocks);
557
558 // The last frame may have an overdetermined block structure given in
559 // the bitstream. In that case the defined block structure would need
560 // more samples than available to be consistent.
561 // The block structure is actually used but the block sizes are adapted
562 // to fit the actual number of available samples.
563 // Example: 5 samples, 2nd level block sizes: 2 2 2 2.
564 // This results in the actual block sizes: 2 2 1 0.
565 // This is not specified in 14496-3 but actually done by the reference
566 // codec RM22 revision 2.
567 // This appears to happen in case of an odd number of samples in the last
568 // frame which is actually not allowed by the block length switching part
569 // of 14496-3.
570 // The ALS conformance files feature an odd number of samples in the last
571 // frame.
572
573 for (b = 0; b < ctx->num_blocks; b++)
574 div_blocks[b] = ctx->sconf.frame_length >> div_blocks[b];
575
576 if (ctx->cur_frame_length != ctx->sconf.frame_length) {
577 unsigned int remaining = ctx->cur_frame_length;
578
579 for (b = 0; b < ctx->num_blocks; b++) {
580 if (remaining <= div_blocks[b]) {
581 div_blocks[b] = remaining;
582 ctx->num_blocks = b + 1;
583 break;
584 }
585
586 remaining -= div_blocks[b];
587 }
588 }
589 }
590
591
592 /** Read the block data for a constant block
593 */
read_const_block_data(ALSDecContext * ctx,ALSBlockData * bd)594 static int read_const_block_data(ALSDecContext *ctx, ALSBlockData *bd)
595 {
596 ALSSpecificConfig *sconf = &ctx->sconf;
597 AVCodecContext *avctx = ctx->avctx;
598 GetBitContext *gb = &ctx->gb;
599
600 if (bd->block_length <= 0)
601 return AVERROR_INVALIDDATA;
602
603 *bd->raw_samples = 0;
604 *bd->const_block = get_bits1(gb); // 1 = constant value, 0 = zero block (silence)
605 bd->js_blocks = get_bits1(gb);
606
607 // skip 5 reserved bits
608 skip_bits(gb, 5);
609
610 if (*bd->const_block) {
611 unsigned int const_val_bits = sconf->floating ? 24 : avctx->bits_per_raw_sample;
612 *bd->raw_samples = get_sbits_long(gb, const_val_bits);
613 }
614
615 // ensure constant block decoding by reusing this field
616 *bd->const_block = 1;
617
618 return 0;
619 }
620
621
622 /** Decode the block data for a constant block
623 */
decode_const_block_data(ALSDecContext * ctx,ALSBlockData * bd)624 static void decode_const_block_data(ALSDecContext *ctx, ALSBlockData *bd)
625 {
626 int smp = bd->block_length - 1;
627 int32_t val = *bd->raw_samples;
628 int32_t *dst = bd->raw_samples + 1;
629
630 // write raw samples into buffer
631 for (; smp; smp--)
632 *dst++ = val;
633 }
634
635
636 /** Read the block data for a non-constant block
637 */
read_var_block_data(ALSDecContext * ctx,ALSBlockData * bd)638 static int read_var_block_data(ALSDecContext *ctx, ALSBlockData *bd)
639 {
640 ALSSpecificConfig *sconf = &ctx->sconf;
641 AVCodecContext *avctx = ctx->avctx;
642 GetBitContext *gb = &ctx->gb;
643 unsigned int k;
644 unsigned int s[8];
645 unsigned int sx[8];
646 unsigned int sub_blocks, log2_sub_blocks, sb_length;
647 unsigned int start = 0;
648 unsigned int opt_order;
649 int sb;
650 int32_t *quant_cof = bd->quant_cof;
651 int32_t *current_res;
652
653
654 // ensure variable block decoding by reusing this field
655 *bd->const_block = 0;
656
657 *bd->opt_order = 1;
658 bd->js_blocks = get_bits1(gb);
659
660 opt_order = *bd->opt_order;
661
662 // determine the number of subblocks for entropy decoding
663 if (!sconf->bgmc && !sconf->sb_part) {
664 log2_sub_blocks = 0;
665 } else {
666 if (sconf->bgmc && sconf->sb_part)
667 log2_sub_blocks = get_bits(gb, 2);
668 else
669 log2_sub_blocks = 2 * get_bits1(gb);
670 }
671
672 sub_blocks = 1 << log2_sub_blocks;
673
674 // do not continue in case of a damaged stream since
675 // block_length must be evenly divisible by sub_blocks
676 if (bd->block_length & (sub_blocks - 1) || bd->block_length <= 0) {
677 av_log(avctx, AV_LOG_WARNING,
678 "Block length is not evenly divisible by the number of subblocks.\n");
679 return AVERROR_INVALIDDATA;
680 }
681
682 sb_length = bd->block_length >> log2_sub_blocks;
683
684 if (sconf->bgmc) {
685 s[0] = get_bits(gb, 8 + (sconf->resolution > 1));
686 for (k = 1; k < sub_blocks; k++)
687 s[k] = s[k - 1] + decode_rice(gb, 2);
688
689 for (k = 0; k < sub_blocks; k++) {
690 sx[k] = s[k] & 0x0F;
691 s [k] >>= 4;
692 }
693 } else {
694 s[0] = get_bits(gb, 4 + (sconf->resolution > 1));
695 for (k = 1; k < sub_blocks; k++)
696 s[k] = s[k - 1] + decode_rice(gb, 0);
697 }
698 for (k = 1; k < sub_blocks; k++)
699 if (s[k] > 32) {
700 av_log(avctx, AV_LOG_ERROR, "k invalid for rice code.\n");
701 return AVERROR_INVALIDDATA;
702 }
703
704 if (get_bits1(gb))
705 *bd->shift_lsbs = get_bits(gb, 4) + 1;
706
707 *bd->store_prev_samples = (bd->js_blocks && bd->raw_other) || *bd->shift_lsbs;
708
709
710 if (!sconf->rlslms) {
711 if (sconf->adapt_order && sconf->max_order) {
712 int opt_order_length = av_ceil_log2(av_clip((bd->block_length >> 3) - 1,
713 2, sconf->max_order + 1));
714 *bd->opt_order = get_bits(gb, opt_order_length);
715 if (*bd->opt_order > sconf->max_order) {
716 *bd->opt_order = sconf->max_order;
717 av_log(avctx, AV_LOG_ERROR, "Predictor order too large.\n");
718 return AVERROR_INVALIDDATA;
719 }
720 } else {
721 *bd->opt_order = sconf->max_order;
722 }
723 opt_order = *bd->opt_order;
724
725 if (opt_order) {
726 int add_base;
727
728 if (sconf->coef_table == 3) {
729 add_base = 0x7F;
730
731 // read coefficient 0
732 quant_cof[0] = 32 * parcor_scaled_values[get_bits(gb, 7)];
733
734 // read coefficient 1
735 if (opt_order > 1)
736 quant_cof[1] = -32 * parcor_scaled_values[get_bits(gb, 7)];
737
738 // read coefficients 2 to opt_order
739 for (k = 2; k < opt_order; k++)
740 quant_cof[k] = get_bits(gb, 7);
741 } else {
742 int k_max;
743 add_base = 1;
744
745 // read coefficient 0 to 19
746 k_max = FFMIN(opt_order, 20);
747 for (k = 0; k < k_max; k++) {
748 int rice_param = parcor_rice_table[sconf->coef_table][k][1];
749 int offset = parcor_rice_table[sconf->coef_table][k][0];
750 quant_cof[k] = decode_rice(gb, rice_param) + offset;
751 if (quant_cof[k] < -64 || quant_cof[k] > 63) {
752 av_log(avctx, AV_LOG_ERROR,
753 "quant_cof %"PRId32" is out of range.\n",
754 quant_cof[k]);
755 return AVERROR_INVALIDDATA;
756 }
757 }
758
759 // read coefficients 20 to 126
760 k_max = FFMIN(opt_order, 127);
761 for (; k < k_max; k++)
762 quant_cof[k] = decode_rice(gb, 2) + (k & 1);
763
764 // read coefficients 127 to opt_order
765 for (; k < opt_order; k++)
766 quant_cof[k] = decode_rice(gb, 1);
767
768 quant_cof[0] = 32 * parcor_scaled_values[quant_cof[0] + 64];
769
770 if (opt_order > 1)
771 quant_cof[1] = -32 * parcor_scaled_values[quant_cof[1] + 64];
772 }
773
774 for (k = 2; k < opt_order; k++)
775 quant_cof[k] = (quant_cof[k] * (1U << 14)) + (add_base << 13);
776 }
777 }
778
779 // read LTP gain and lag values
780 if (sconf->long_term_prediction) {
781 *bd->use_ltp = get_bits1(gb);
782
783 if (*bd->use_ltp) {
784 int r, c;
785
786 bd->ltp_gain[0] = decode_rice(gb, 1) * 8;
787 bd->ltp_gain[1] = decode_rice(gb, 2) * 8;
788
789 r = get_unary(gb, 0, 4);
790 c = get_bits(gb, 2);
791 if (r >= 4) {
792 av_log(avctx, AV_LOG_ERROR, "r overflow\n");
793 return AVERROR_INVALIDDATA;
794 }
795
796 bd->ltp_gain[2] = ltp_gain_values[r][c];
797
798 bd->ltp_gain[3] = decode_rice(gb, 2) * 8;
799 bd->ltp_gain[4] = decode_rice(gb, 1) * 8;
800
801 *bd->ltp_lag = get_bits(gb, ctx->ltp_lag_length);
802 *bd->ltp_lag += FFMAX(4, opt_order + 1);
803 }
804 }
805
806 // read first value and residuals in case of a random access block
807 if (bd->ra_block) {
808 start = FFMIN(opt_order, 3);
809 av_assert0(sb_length <= sconf->frame_length);
810 if (sb_length <= start) {
811 // opt_order or sb_length may be corrupted, either way this is unsupported and not well defined in the specification
812 av_log(avctx, AV_LOG_ERROR, "Sub block length smaller or equal start\n");
813 return AVERROR_PATCHWELCOME;
814 }
815
816 if (opt_order)
817 bd->raw_samples[0] = decode_rice(gb, avctx->bits_per_raw_sample - 4);
818 if (opt_order > 1)
819 bd->raw_samples[1] = decode_rice(gb, FFMIN(s[0] + 3, ctx->s_max));
820 if (opt_order > 2)
821 bd->raw_samples[2] = decode_rice(gb, FFMIN(s[0] + 1, ctx->s_max));
822 }
823
824 // read all residuals
825 if (sconf->bgmc) {
826 int delta[8];
827 unsigned int k [8];
828 unsigned int b = av_clip((av_ceil_log2(bd->block_length) - 3) >> 1, 0, 5);
829
830 // read most significant bits
831 unsigned int high;
832 unsigned int low;
833 unsigned int value;
834
835 int ret = ff_bgmc_decode_init(gb, &high, &low, &value);
836 if (ret < 0)
837 return ret;
838
839 current_res = bd->raw_samples + start;
840
841 for (sb = 0; sb < sub_blocks; sb++) {
842 unsigned int sb_len = sb_length - (sb ? 0 : start);
843
844 k [sb] = s[sb] > b ? s[sb] - b : 0;
845 delta[sb] = 5 - s[sb] + k[sb];
846
847 if (k[sb] >= 32)
848 return AVERROR_INVALIDDATA;
849
850 ff_bgmc_decode(gb, sb_len, current_res,
851 delta[sb], sx[sb], &high, &low, &value, ctx->bgmc_lut, ctx->bgmc_lut_status);
852
853 current_res += sb_len;
854 }
855
856 ff_bgmc_decode_end(gb);
857
858
859 // read least significant bits and tails
860 current_res = bd->raw_samples + start;
861
862 for (sb = 0; sb < sub_blocks; sb++, start = 0) {
863 unsigned int cur_tail_code = tail_code[sx[sb]][delta[sb]];
864 unsigned int cur_k = k[sb];
865 unsigned int cur_s = s[sb];
866
867 for (; start < sb_length; start++) {
868 int32_t res = *current_res;
869
870 if (res == cur_tail_code) {
871 unsigned int max_msb = (2 + (sx[sb] > 2) + (sx[sb] > 10))
872 << (5 - delta[sb]);
873
874 res = decode_rice(gb, cur_s);
875
876 if (res >= 0) {
877 res += (max_msb ) << cur_k;
878 } else {
879 res -= (max_msb - 1) << cur_k;
880 }
881 } else {
882 if (res > cur_tail_code)
883 res--;
884
885 if (res & 1)
886 res = -res;
887
888 res >>= 1;
889
890 if (cur_k) {
891 res *= 1U << cur_k;
892 res |= get_bits_long(gb, cur_k);
893 }
894 }
895
896 *current_res++ = res;
897 }
898 }
899 } else {
900 current_res = bd->raw_samples + start;
901
902 for (sb = 0; sb < sub_blocks; sb++, start = 0)
903 for (; start < sb_length; start++)
904 *current_res++ = decode_rice(gb, s[sb]);
905 }
906
907 return 0;
908 }
909
910
911 /** Decode the block data for a non-constant block
912 */
decode_var_block_data(ALSDecContext * ctx,ALSBlockData * bd)913 static int decode_var_block_data(ALSDecContext *ctx, ALSBlockData *bd)
914 {
915 ALSSpecificConfig *sconf = &ctx->sconf;
916 unsigned int block_length = bd->block_length;
917 unsigned int smp = 0;
918 unsigned int k;
919 int opt_order = *bd->opt_order;
920 int sb;
921 int64_t y;
922 int32_t *quant_cof = bd->quant_cof;
923 int32_t *lpc_cof = bd->lpc_cof;
924 int32_t *raw_samples = bd->raw_samples;
925 int32_t *raw_samples_end = bd->raw_samples + bd->block_length;
926 int32_t *lpc_cof_reversed = ctx->lpc_cof_reversed_buffer;
927
928 // reverse long-term prediction
929 if (*bd->use_ltp) {
930 int ltp_smp;
931
932 for (ltp_smp = FFMAX(*bd->ltp_lag - 2, 0); ltp_smp < block_length; ltp_smp++) {
933 int center = ltp_smp - *bd->ltp_lag;
934 int begin = FFMAX(0, center - 2);
935 int end = center + 3;
936 int tab = 5 - (end - begin);
937 int base;
938
939 y = 1 << 6;
940
941 for (base = begin; base < end; base++, tab++)
942 y += (uint64_t)MUL64(bd->ltp_gain[tab], raw_samples[base]);
943
944 raw_samples[ltp_smp] += y >> 7;
945 }
946 }
947
948 // reconstruct all samples from residuals
949 if (bd->ra_block) {
950 for (smp = 0; smp < FFMIN(opt_order, block_length); smp++) {
951 y = 1 << 19;
952
953 for (sb = 0; sb < smp; sb++)
954 y += (uint64_t)MUL64(lpc_cof[sb], raw_samples[-(sb + 1)]);
955
956 *raw_samples++ -= y >> 20;
957 parcor_to_lpc(smp, quant_cof, lpc_cof);
958 }
959 } else {
960 for (k = 0; k < opt_order; k++)
961 parcor_to_lpc(k, quant_cof, lpc_cof);
962
963 // store previous samples in case that they have to be altered
964 if (*bd->store_prev_samples)
965 memcpy(bd->prev_raw_samples, raw_samples - sconf->max_order,
966 sizeof(*bd->prev_raw_samples) * sconf->max_order);
967
968 // reconstruct difference signal for prediction (joint-stereo)
969 if (bd->js_blocks && bd->raw_other) {
970 uint32_t *left, *right;
971
972 if (bd->raw_other > raw_samples) { // D = R - L
973 left = raw_samples;
974 right = bd->raw_other;
975 } else { // D = R - L
976 left = bd->raw_other;
977 right = raw_samples;
978 }
979
980 for (sb = -1; sb >= -sconf->max_order; sb--)
981 raw_samples[sb] = right[sb] - left[sb];
982 }
983
984 // reconstruct shifted signal
985 if (*bd->shift_lsbs)
986 for (sb = -1; sb >= -sconf->max_order; sb--)
987 raw_samples[sb] >>= *bd->shift_lsbs;
988 }
989
990 // reverse linear prediction coefficients for efficiency
991 lpc_cof = lpc_cof + opt_order;
992
993 for (sb = 0; sb < opt_order; sb++)
994 lpc_cof_reversed[sb] = lpc_cof[-(sb + 1)];
995
996 // reconstruct raw samples
997 raw_samples = bd->raw_samples + smp;
998 lpc_cof = lpc_cof_reversed + opt_order;
999
1000 for (; raw_samples < raw_samples_end; raw_samples++) {
1001 y = 1 << 19;
1002
1003 for (sb = -opt_order; sb < 0; sb++)
1004 y += (uint64_t)MUL64(lpc_cof[sb], raw_samples[sb]);
1005
1006 *raw_samples -= y >> 20;
1007 }
1008
1009 raw_samples = bd->raw_samples;
1010
1011 // restore previous samples in case that they have been altered
1012 if (*bd->store_prev_samples)
1013 memcpy(raw_samples - sconf->max_order, bd->prev_raw_samples,
1014 sizeof(*raw_samples) * sconf->max_order);
1015
1016 return 0;
1017 }
1018
1019
1020 /** Read the block data.
1021 */
read_block(ALSDecContext * ctx,ALSBlockData * bd)1022 static int read_block(ALSDecContext *ctx, ALSBlockData *bd)
1023 {
1024 int ret;
1025 GetBitContext *gb = &ctx->gb;
1026 ALSSpecificConfig *sconf = &ctx->sconf;
1027
1028 *bd->shift_lsbs = 0;
1029
1030 if (get_bits_left(gb) < 7)
1031 return AVERROR_INVALIDDATA;
1032
1033 // read block type flag and read the samples accordingly
1034 if (get_bits1(gb)) {
1035 ret = read_var_block_data(ctx, bd);
1036 } else {
1037 ret = read_const_block_data(ctx, bd);
1038 }
1039
1040 if (!sconf->mc_coding || ctx->js_switch)
1041 align_get_bits(gb);
1042
1043 return ret;
1044 }
1045
1046
1047 /** Decode the block data.
1048 */
decode_block(ALSDecContext * ctx,ALSBlockData * bd)1049 static int decode_block(ALSDecContext *ctx, ALSBlockData *bd)
1050 {
1051 unsigned int smp;
1052 int ret = 0;
1053
1054 // read block type flag and read the samples accordingly
1055 if (*bd->const_block)
1056 decode_const_block_data(ctx, bd);
1057 else
1058 ret = decode_var_block_data(ctx, bd); // always return 0
1059
1060 if (ret < 0)
1061 return ret;
1062
1063 // TODO: read RLSLMS extension data
1064
1065 if (*bd->shift_lsbs)
1066 for (smp = 0; smp < bd->block_length; smp++)
1067 bd->raw_samples[smp] = (unsigned)bd->raw_samples[smp] << *bd->shift_lsbs;
1068
1069 return 0;
1070 }
1071
1072
1073 /** Read and decode block data successively.
1074 */
read_decode_block(ALSDecContext * ctx,ALSBlockData * bd)1075 static int read_decode_block(ALSDecContext *ctx, ALSBlockData *bd)
1076 {
1077 int ret;
1078
1079 if ((ret = read_block(ctx, bd)) < 0)
1080 return ret;
1081
1082 return decode_block(ctx, bd);
1083 }
1084
1085
1086 /** Compute the number of samples left to decode for the current frame and
1087 * sets these samples to zero.
1088 */
zero_remaining(unsigned int b,unsigned int b_max,const unsigned int * div_blocks,int32_t * buf)1089 static void zero_remaining(unsigned int b, unsigned int b_max,
1090 const unsigned int *div_blocks, int32_t *buf)
1091 {
1092 unsigned int count = 0;
1093
1094 while (b < b_max)
1095 count += div_blocks[b++];
1096
1097 if (count)
1098 memset(buf, 0, sizeof(*buf) * count);
1099 }
1100
1101
1102 /** Decode blocks independently.
1103 */
decode_blocks_ind(ALSDecContext * ctx,unsigned int ra_frame,unsigned int c,const unsigned int * div_blocks,unsigned int * js_blocks)1104 static int decode_blocks_ind(ALSDecContext *ctx, unsigned int ra_frame,
1105 unsigned int c, const unsigned int *div_blocks,
1106 unsigned int *js_blocks)
1107 {
1108 int ret;
1109 unsigned int b;
1110 ALSBlockData bd = { 0 };
1111
1112 bd.ra_block = ra_frame;
1113 bd.const_block = ctx->const_block;
1114 bd.shift_lsbs = ctx->shift_lsbs;
1115 bd.opt_order = ctx->opt_order;
1116 bd.store_prev_samples = ctx->store_prev_samples;
1117 bd.use_ltp = ctx->use_ltp;
1118 bd.ltp_lag = ctx->ltp_lag;
1119 bd.ltp_gain = ctx->ltp_gain[0];
1120 bd.quant_cof = ctx->quant_cof[0];
1121 bd.lpc_cof = ctx->lpc_cof[0];
1122 bd.prev_raw_samples = ctx->prev_raw_samples;
1123 bd.raw_samples = ctx->raw_samples[c];
1124
1125
1126 for (b = 0; b < ctx->num_blocks; b++) {
1127 bd.block_length = div_blocks[b];
1128
1129 if ((ret = read_decode_block(ctx, &bd)) < 0) {
1130 // damaged block, write zero for the rest of the frame
1131 zero_remaining(b, ctx->num_blocks, div_blocks, bd.raw_samples);
1132 return ret;
1133 }
1134 bd.raw_samples += div_blocks[b];
1135 bd.ra_block = 0;
1136 }
1137
1138 return 0;
1139 }
1140
1141
1142 /** Decode blocks dependently.
1143 */
decode_blocks(ALSDecContext * ctx,unsigned int ra_frame,unsigned int c,const unsigned int * div_blocks,unsigned int * js_blocks)1144 static int decode_blocks(ALSDecContext *ctx, unsigned int ra_frame,
1145 unsigned int c, const unsigned int *div_blocks,
1146 unsigned int *js_blocks)
1147 {
1148 ALSSpecificConfig *sconf = &ctx->sconf;
1149 unsigned int offset = 0;
1150 unsigned int b;
1151 int ret;
1152 ALSBlockData bd[2] = { { 0 } };
1153
1154 bd[0].ra_block = ra_frame;
1155 bd[0].const_block = ctx->const_block;
1156 bd[0].shift_lsbs = ctx->shift_lsbs;
1157 bd[0].opt_order = ctx->opt_order;
1158 bd[0].store_prev_samples = ctx->store_prev_samples;
1159 bd[0].use_ltp = ctx->use_ltp;
1160 bd[0].ltp_lag = ctx->ltp_lag;
1161 bd[0].ltp_gain = ctx->ltp_gain[0];
1162 bd[0].quant_cof = ctx->quant_cof[0];
1163 bd[0].lpc_cof = ctx->lpc_cof[0];
1164 bd[0].prev_raw_samples = ctx->prev_raw_samples;
1165 bd[0].js_blocks = *js_blocks;
1166
1167 bd[1].ra_block = ra_frame;
1168 bd[1].const_block = ctx->const_block;
1169 bd[1].shift_lsbs = ctx->shift_lsbs;
1170 bd[1].opt_order = ctx->opt_order;
1171 bd[1].store_prev_samples = ctx->store_prev_samples;
1172 bd[1].use_ltp = ctx->use_ltp;
1173 bd[1].ltp_lag = ctx->ltp_lag;
1174 bd[1].ltp_gain = ctx->ltp_gain[0];
1175 bd[1].quant_cof = ctx->quant_cof[0];
1176 bd[1].lpc_cof = ctx->lpc_cof[0];
1177 bd[1].prev_raw_samples = ctx->prev_raw_samples;
1178 bd[1].js_blocks = *(js_blocks + 1);
1179
1180 // decode all blocks
1181 for (b = 0; b < ctx->num_blocks; b++) {
1182 unsigned int s;
1183
1184 bd[0].block_length = div_blocks[b];
1185 bd[1].block_length = div_blocks[b];
1186
1187 bd[0].raw_samples = ctx->raw_samples[c ] + offset;
1188 bd[1].raw_samples = ctx->raw_samples[c + 1] + offset;
1189
1190 bd[0].raw_other = bd[1].raw_samples;
1191 bd[1].raw_other = bd[0].raw_samples;
1192
1193 if ((ret = read_decode_block(ctx, &bd[0])) < 0 ||
1194 (ret = read_decode_block(ctx, &bd[1])) < 0)
1195 goto fail;
1196
1197 // reconstruct joint-stereo blocks
1198 if (bd[0].js_blocks) {
1199 if (bd[1].js_blocks)
1200 av_log(ctx->avctx, AV_LOG_WARNING, "Invalid channel pair.\n");
1201
1202 for (s = 0; s < div_blocks[b]; s++)
1203 bd[0].raw_samples[s] = bd[1].raw_samples[s] - (unsigned)bd[0].raw_samples[s];
1204 } else if (bd[1].js_blocks) {
1205 for (s = 0; s < div_blocks[b]; s++)
1206 bd[1].raw_samples[s] = bd[1].raw_samples[s] + (unsigned)bd[0].raw_samples[s];
1207 }
1208
1209 offset += div_blocks[b];
1210 bd[0].ra_block = 0;
1211 bd[1].ra_block = 0;
1212 }
1213
1214 // store carryover raw samples,
1215 // the others channel raw samples are stored by the calling function.
1216 memmove(ctx->raw_samples[c] - sconf->max_order,
1217 ctx->raw_samples[c] - sconf->max_order + sconf->frame_length,
1218 sizeof(*ctx->raw_samples[c]) * sconf->max_order);
1219
1220 return 0;
1221 fail:
1222 // damaged block, write zero for the rest of the frame
1223 zero_remaining(b, ctx->num_blocks, div_blocks, bd[0].raw_samples);
1224 zero_remaining(b, ctx->num_blocks, div_blocks, bd[1].raw_samples);
1225 return ret;
1226 }
1227
als_weighting(GetBitContext * gb,int k,int off)1228 static inline int als_weighting(GetBitContext *gb, int k, int off)
1229 {
1230 int idx = av_clip(decode_rice(gb, k) + off,
1231 0, FF_ARRAY_ELEMS(mcc_weightings) - 1);
1232 return mcc_weightings[idx];
1233 }
1234
1235 /** Read the channel data.
1236 */
read_channel_data(ALSDecContext * ctx,ALSChannelData * cd,int c)1237 static int read_channel_data(ALSDecContext *ctx, ALSChannelData *cd, int c)
1238 {
1239 GetBitContext *gb = &ctx->gb;
1240 ALSChannelData *current = cd;
1241 unsigned int channels = ctx->avctx->ch_layout.nb_channels;
1242 int entries = 0;
1243
1244 while (entries < channels && !(current->stop_flag = get_bits1(gb))) {
1245 current->master_channel = get_bits_long(gb, av_ceil_log2(channels));
1246
1247 if (current->master_channel >= channels) {
1248 av_log(ctx->avctx, AV_LOG_ERROR, "Invalid master channel.\n");
1249 return AVERROR_INVALIDDATA;
1250 }
1251
1252 if (current->master_channel != c) {
1253 current->time_diff_flag = get_bits1(gb);
1254 current->weighting[0] = als_weighting(gb, 1, 16);
1255 current->weighting[1] = als_weighting(gb, 2, 14);
1256 current->weighting[2] = als_weighting(gb, 1, 16);
1257
1258 if (current->time_diff_flag) {
1259 current->weighting[3] = als_weighting(gb, 1, 16);
1260 current->weighting[4] = als_weighting(gb, 1, 16);
1261 current->weighting[5] = als_weighting(gb, 1, 16);
1262
1263 current->time_diff_sign = get_bits1(gb);
1264 current->time_diff_index = get_bits(gb, ctx->ltp_lag_length - 3) + 3;
1265 }
1266 }
1267
1268 current++;
1269 entries++;
1270 }
1271
1272 if (entries == channels) {
1273 av_log(ctx->avctx, AV_LOG_ERROR, "Damaged channel data.\n");
1274 return AVERROR_INVALIDDATA;
1275 }
1276
1277 align_get_bits(gb);
1278 return 0;
1279 }
1280
1281
1282 /** Recursively reverts the inter-channel correlation for a block.
1283 */
revert_channel_correlation(ALSDecContext * ctx,ALSBlockData * bd,ALSChannelData ** cd,int * reverted,unsigned int offset,int c)1284 static int revert_channel_correlation(ALSDecContext *ctx, ALSBlockData *bd,
1285 ALSChannelData **cd, int *reverted,
1286 unsigned int offset, int c)
1287 {
1288 ALSChannelData *ch = cd[c];
1289 unsigned int dep = 0;
1290 unsigned int channels = ctx->avctx->ch_layout.nb_channels;
1291 unsigned int channel_size = ctx->sconf.frame_length + ctx->sconf.max_order;
1292
1293 if (reverted[c])
1294 return 0;
1295
1296 reverted[c] = 1;
1297
1298 while (dep < channels && !ch[dep].stop_flag) {
1299 revert_channel_correlation(ctx, bd, cd, reverted, offset,
1300 ch[dep].master_channel);
1301
1302 dep++;
1303 }
1304
1305 if (dep == channels) {
1306 av_log(ctx->avctx, AV_LOG_WARNING, "Invalid channel correlation.\n");
1307 return AVERROR_INVALIDDATA;
1308 }
1309
1310 bd->const_block = ctx->const_block + c;
1311 bd->shift_lsbs = ctx->shift_lsbs + c;
1312 bd->opt_order = ctx->opt_order + c;
1313 bd->store_prev_samples = ctx->store_prev_samples + c;
1314 bd->use_ltp = ctx->use_ltp + c;
1315 bd->ltp_lag = ctx->ltp_lag + c;
1316 bd->ltp_gain = ctx->ltp_gain[c];
1317 bd->lpc_cof = ctx->lpc_cof[c];
1318 bd->quant_cof = ctx->quant_cof[c];
1319 bd->raw_samples = ctx->raw_samples[c] + offset;
1320
1321 for (dep = 0; !ch[dep].stop_flag; dep++) {
1322 ptrdiff_t smp;
1323 ptrdiff_t begin = 1;
1324 ptrdiff_t end = bd->block_length - 1;
1325 int64_t y;
1326 int32_t *master = ctx->raw_samples[ch[dep].master_channel] + offset;
1327
1328 if (ch[dep].master_channel == c)
1329 continue;
1330
1331 if (ch[dep].time_diff_flag) {
1332 int t = ch[dep].time_diff_index;
1333
1334 if (ch[dep].time_diff_sign) {
1335 t = -t;
1336 if (begin < t) {
1337 av_log(ctx->avctx, AV_LOG_ERROR, "begin %"PTRDIFF_SPECIFIER" smaller than time diff index %d.\n", begin, t);
1338 return AVERROR_INVALIDDATA;
1339 }
1340 begin -= t;
1341 } else {
1342 if (end < t) {
1343 av_log(ctx->avctx, AV_LOG_ERROR, "end %"PTRDIFF_SPECIFIER" smaller than time diff index %d.\n", end, t);
1344 return AVERROR_INVALIDDATA;
1345 }
1346 end -= t;
1347 }
1348
1349 if (FFMIN(begin - 1, begin - 1 + t) < ctx->raw_buffer - master ||
1350 FFMAX(end + 1, end + 1 + t) > ctx->raw_buffer + channels * channel_size - master) {
1351 av_log(ctx->avctx, AV_LOG_ERROR,
1352 "sample pointer range [%p, %p] not contained in raw_buffer [%p, %p].\n",
1353 master + FFMIN(begin - 1, begin - 1 + t), master + FFMAX(end + 1, end + 1 + t),
1354 ctx->raw_buffer, ctx->raw_buffer + channels * channel_size);
1355 return AVERROR_INVALIDDATA;
1356 }
1357
1358 for (smp = begin; smp < end; smp++) {
1359 y = (1 << 6) +
1360 MUL64(ch[dep].weighting[0], master[smp - 1 ]) +
1361 MUL64(ch[dep].weighting[1], master[smp ]) +
1362 MUL64(ch[dep].weighting[2], master[smp + 1 ]) +
1363 MUL64(ch[dep].weighting[3], master[smp - 1 + t]) +
1364 MUL64(ch[dep].weighting[4], master[smp + t]) +
1365 MUL64(ch[dep].weighting[5], master[smp + 1 + t]);
1366
1367 bd->raw_samples[smp] += y >> 7;
1368 }
1369 } else {
1370
1371 if (begin - 1 < ctx->raw_buffer - master ||
1372 end + 1 > ctx->raw_buffer + channels * channel_size - master) {
1373 av_log(ctx->avctx, AV_LOG_ERROR,
1374 "sample pointer range [%p, %p] not contained in raw_buffer [%p, %p].\n",
1375 master + begin - 1, master + end + 1,
1376 ctx->raw_buffer, ctx->raw_buffer + channels * channel_size);
1377 return AVERROR_INVALIDDATA;
1378 }
1379
1380 for (smp = begin; smp < end; smp++) {
1381 y = (1 << 6) +
1382 MUL64(ch[dep].weighting[0], master[smp - 1]) +
1383 MUL64(ch[dep].weighting[1], master[smp ]) +
1384 MUL64(ch[dep].weighting[2], master[smp + 1]);
1385
1386 bd->raw_samples[smp] += y >> 7;
1387 }
1388 }
1389 }
1390
1391 return 0;
1392 }
1393
1394
1395 /** multiply two softfloats and handle the rounding off
1396 */
multiply(SoftFloat_IEEE754 a,SoftFloat_IEEE754 b)1397 static SoftFloat_IEEE754 multiply(SoftFloat_IEEE754 a, SoftFloat_IEEE754 b) {
1398 uint64_t mantissa_temp;
1399 uint64_t mask_64;
1400 int cutoff_bit_count;
1401 unsigned char last_2_bits;
1402 unsigned int mantissa;
1403 int32_t sign;
1404 uint32_t return_val = 0;
1405 int bit_count = 48;
1406
1407 sign = a.sign ^ b.sign;
1408
1409 // Multiply mantissa bits in a 64-bit register
1410 mantissa_temp = (uint64_t)a.mant * (uint64_t)b.mant;
1411 mask_64 = (uint64_t)0x1 << 47;
1412
1413 if (!mantissa_temp)
1414 return FLOAT_0;
1415
1416 // Count the valid bit count
1417 while (!(mantissa_temp & mask_64) && mask_64) {
1418 bit_count--;
1419 mask_64 >>= 1;
1420 }
1421
1422 // Round off
1423 cutoff_bit_count = bit_count - 24;
1424 if (cutoff_bit_count > 0) {
1425 last_2_bits = (unsigned char)(((unsigned int)mantissa_temp >> (cutoff_bit_count - 1)) & 0x3 );
1426 if ((last_2_bits == 0x3) || ((last_2_bits == 0x1) && ((unsigned int)mantissa_temp & ((0x1UL << (cutoff_bit_count - 1)) - 1)))) {
1427 // Need to round up
1428 mantissa_temp += (uint64_t)0x1 << cutoff_bit_count;
1429 }
1430 }
1431
1432 if (cutoff_bit_count >= 0) {
1433 mantissa = (unsigned int)(mantissa_temp >> cutoff_bit_count);
1434 } else {
1435 mantissa = (unsigned int)(mantissa_temp <<-cutoff_bit_count);
1436 }
1437
1438 // Need one more shift?
1439 if (mantissa & 0x01000000ul) {
1440 bit_count++;
1441 mantissa >>= 1;
1442 }
1443
1444 if (!sign) {
1445 return_val = 0x80000000U;
1446 }
1447
1448 return_val |= ((unsigned)av_clip(a.exp + b.exp + bit_count - 47, -126, 127) << 23) & 0x7F800000;
1449 return_val |= mantissa;
1450 return av_bits2sf_ieee754(return_val);
1451 }
1452
1453
1454 /** Read and decode the floating point sample data
1455 */
read_diff_float_data(ALSDecContext * ctx,unsigned int ra_frame)1456 static int read_diff_float_data(ALSDecContext *ctx, unsigned int ra_frame) {
1457 AVCodecContext *avctx = ctx->avctx;
1458 GetBitContext *gb = &ctx->gb;
1459 SoftFloat_IEEE754 *acf = ctx->acf;
1460 int *shift_value = ctx->shift_value;
1461 int *last_shift_value = ctx->last_shift_value;
1462 int *last_acf_mantissa = ctx->last_acf_mantissa;
1463 int **raw_mantissa = ctx->raw_mantissa;
1464 int *nbits = ctx->nbits;
1465 unsigned char *larray = ctx->larray;
1466 int frame_length = ctx->cur_frame_length;
1467 SoftFloat_IEEE754 scale = av_int2sf_ieee754(0x1u, 23);
1468 unsigned int partA_flag;
1469 unsigned int highest_byte;
1470 unsigned int shift_amp;
1471 uint32_t tmp_32;
1472 int use_acf;
1473 int nchars;
1474 int i;
1475 int c;
1476 long k;
1477 long nbits_aligned;
1478 unsigned long acc;
1479 unsigned long j;
1480 uint32_t sign;
1481 uint32_t e;
1482 uint32_t mantissa;
1483
1484 skip_bits_long(gb, 32); //num_bytes_diff_float
1485 use_acf = get_bits1(gb);
1486
1487 if (ra_frame) {
1488 memset(last_acf_mantissa, 0, avctx->ch_layout.nb_channels * sizeof(*last_acf_mantissa));
1489 memset(last_shift_value, 0, avctx->ch_layout.nb_channels * sizeof(*last_shift_value) );
1490 ff_mlz_flush_dict(ctx->mlz);
1491 }
1492
1493 if (avctx->ch_layout.nb_channels * 8 > get_bits_left(gb))
1494 return AVERROR_INVALIDDATA;
1495
1496 for (c = 0; c < avctx->ch_layout.nb_channels; ++c) {
1497 if (use_acf) {
1498 //acf_flag
1499 if (get_bits1(gb)) {
1500 tmp_32 = get_bits(gb, 23);
1501 last_acf_mantissa[c] = tmp_32;
1502 } else {
1503 tmp_32 = last_acf_mantissa[c];
1504 }
1505 acf[c] = av_bits2sf_ieee754(tmp_32);
1506 } else {
1507 acf[c] = FLOAT_1;
1508 }
1509
1510 highest_byte = get_bits(gb, 2);
1511 partA_flag = get_bits1(gb);
1512 shift_amp = get_bits1(gb);
1513
1514 if (shift_amp) {
1515 shift_value[c] = get_bits(gb, 8);
1516 last_shift_value[c] = shift_value[c];
1517 } else {
1518 shift_value[c] = last_shift_value[c];
1519 }
1520
1521 if (partA_flag) {
1522 if (!get_bits1(gb)) { //uncompressed
1523 for (i = 0; i < frame_length; ++i) {
1524 if (ctx->raw_samples[c][i] == 0) {
1525 ctx->raw_mantissa[c][i] = get_bits_long(gb, 32);
1526 }
1527 }
1528 } else { //compressed
1529 nchars = 0;
1530 for (i = 0; i < frame_length; ++i) {
1531 if (ctx->raw_samples[c][i] == 0) {
1532 nchars += 4;
1533 }
1534 }
1535
1536 tmp_32 = ff_mlz_decompression(ctx->mlz, gb, nchars, larray);
1537 if(tmp_32 != nchars) {
1538 av_log(ctx->avctx, AV_LOG_ERROR, "Error in MLZ decompression (%"PRId32", %d).\n", tmp_32, nchars);
1539 return AVERROR_INVALIDDATA;
1540 }
1541
1542 for (i = 0; i < frame_length; ++i) {
1543 ctx->raw_mantissa[c][i] = AV_RB32(larray);
1544 }
1545 }
1546 }
1547
1548 //decode part B
1549 if (highest_byte) {
1550 for (i = 0; i < frame_length; ++i) {
1551 if (ctx->raw_samples[c][i] != 0) {
1552 //The following logic is taken from Tabel 14.45 and 14.46 from the ISO spec
1553 if (av_cmp_sf_ieee754(acf[c], FLOAT_1)) {
1554 nbits[i] = 23 - av_log2(abs(ctx->raw_samples[c][i]));
1555 } else {
1556 nbits[i] = 23;
1557 }
1558 nbits[i] = FFMIN(nbits[i], highest_byte*8);
1559 }
1560 }
1561
1562 if (!get_bits1(gb)) { //uncompressed
1563 for (i = 0; i < frame_length; ++i) {
1564 if (ctx->raw_samples[c][i] != 0) {
1565 raw_mantissa[c][i] = get_bitsz(gb, nbits[i]);
1566 }
1567 }
1568 } else { //compressed
1569 nchars = 0;
1570 for (i = 0; i < frame_length; ++i) {
1571 if (ctx->raw_samples[c][i]) {
1572 nchars += (int) nbits[i] / 8;
1573 if (nbits[i] & 7) {
1574 ++nchars;
1575 }
1576 }
1577 }
1578
1579 tmp_32 = ff_mlz_decompression(ctx->mlz, gb, nchars, larray);
1580 if(tmp_32 != nchars) {
1581 av_log(ctx->avctx, AV_LOG_ERROR, "Error in MLZ decompression (%"PRId32", %d).\n", tmp_32, nchars);
1582 return AVERROR_INVALIDDATA;
1583 }
1584
1585 j = 0;
1586 for (i = 0; i < frame_length; ++i) {
1587 if (ctx->raw_samples[c][i]) {
1588 if (nbits[i] & 7) {
1589 nbits_aligned = 8 * ((unsigned int)(nbits[i] / 8) + 1);
1590 } else {
1591 nbits_aligned = nbits[i];
1592 }
1593 acc = 0;
1594 for (k = 0; k < nbits_aligned/8; ++k) {
1595 acc = (acc << 8) + larray[j++];
1596 }
1597 acc >>= (nbits_aligned - nbits[i]);
1598 raw_mantissa[c][i] = acc;
1599 }
1600 }
1601 }
1602 }
1603
1604 for (i = 0; i < frame_length; ++i) {
1605 SoftFloat_IEEE754 pcm_sf = av_int2sf_ieee754(ctx->raw_samples[c][i], 0);
1606 pcm_sf = av_div_sf_ieee754(pcm_sf, scale);
1607
1608 if (ctx->raw_samples[c][i] != 0) {
1609 if (!av_cmp_sf_ieee754(acf[c], FLOAT_1)) {
1610 pcm_sf = multiply(acf[c], pcm_sf);
1611 }
1612
1613 sign = pcm_sf.sign;
1614 e = pcm_sf.exp;
1615 mantissa = (pcm_sf.mant | 0x800000) + raw_mantissa[c][i];
1616
1617 while(mantissa >= 0x1000000) {
1618 e++;
1619 mantissa >>= 1;
1620 }
1621
1622 if (mantissa) e += (shift_value[c] - 127);
1623 mantissa &= 0x007fffffUL;
1624
1625 tmp_32 = (sign << 31) | ((e + EXP_BIAS) << 23) | (mantissa);
1626 ctx->raw_samples[c][i] = tmp_32;
1627 } else {
1628 ctx->raw_samples[c][i] = raw_mantissa[c][i] & 0x007fffffUL;
1629 }
1630 }
1631 align_get_bits(gb);
1632 }
1633 return 0;
1634 }
1635
1636
1637 /** Read the frame data.
1638 */
read_frame_data(ALSDecContext * ctx,unsigned int ra_frame)1639 static int read_frame_data(ALSDecContext *ctx, unsigned int ra_frame)
1640 {
1641 ALSSpecificConfig *sconf = &ctx->sconf;
1642 AVCodecContext *avctx = ctx->avctx;
1643 GetBitContext *gb = &ctx->gb;
1644 unsigned int div_blocks[32]; ///< block sizes.
1645 int c;
1646 unsigned int js_blocks[2];
1647 int channels = avctx->ch_layout.nb_channels;
1648 uint32_t bs_info = 0;
1649 int ret;
1650
1651 // skip the size of the ra unit if present in the frame
1652 if (sconf->ra_flag == RA_FLAG_FRAMES && ra_frame)
1653 skip_bits_long(gb, 32);
1654
1655 if (sconf->mc_coding && sconf->joint_stereo) {
1656 ctx->js_switch = get_bits1(gb);
1657 align_get_bits(gb);
1658 }
1659
1660 if (!sconf->mc_coding || ctx->js_switch) {
1661 int independent_bs = !sconf->joint_stereo;
1662 if (get_bits_left(gb) < 7*channels*ctx->num_blocks)
1663 return AVERROR_INVALIDDATA;
1664 for (c = 0; c < channels; c++) {
1665 js_blocks[0] = 0;
1666 js_blocks[1] = 0;
1667
1668 get_block_sizes(ctx, div_blocks, &bs_info);
1669
1670 // if joint_stereo and block_switching is set, independent decoding
1671 // is signaled via the first bit of bs_info
1672 if (sconf->joint_stereo && sconf->block_switching)
1673 if (bs_info >> 31)
1674 independent_bs = 2;
1675
1676 // if this is the last channel, it has to be decoded independently
1677 if (c == channels - 1 || (c & 1))
1678 independent_bs = 1;
1679
1680 if (independent_bs) {
1681 ret = decode_blocks_ind(ctx, ra_frame, c,
1682 div_blocks, js_blocks);
1683 if (ret < 0)
1684 return ret;
1685 independent_bs--;
1686 } else {
1687 ret = decode_blocks(ctx, ra_frame, c, div_blocks, js_blocks);
1688 if (ret < 0)
1689 return ret;
1690
1691 c++;
1692 }
1693
1694 // store carryover raw samples
1695 memmove(ctx->raw_samples[c] - sconf->max_order,
1696 ctx->raw_samples[c] - sconf->max_order + sconf->frame_length,
1697 sizeof(*ctx->raw_samples[c]) * sconf->max_order);
1698 ctx->highest_decoded_channel = c;
1699 }
1700 } else { // multi-channel coding
1701 ALSBlockData bd = { 0 };
1702 int b, ret;
1703 int *reverted_channels = ctx->reverted_channels;
1704 unsigned int offset = 0;
1705
1706 for (c = 0; c < channels; c++)
1707 if (ctx->chan_data[c] < ctx->chan_data_buffer) {
1708 av_log(ctx->avctx, AV_LOG_ERROR, "Invalid channel data.\n");
1709 return AVERROR_INVALIDDATA;
1710 }
1711
1712 memset(reverted_channels, 0, sizeof(*reverted_channels) * channels);
1713
1714 bd.ra_block = ra_frame;
1715 bd.prev_raw_samples = ctx->prev_raw_samples;
1716
1717 get_block_sizes(ctx, div_blocks, &bs_info);
1718
1719 for (b = 0; b < ctx->num_blocks; b++) {
1720 bd.block_length = div_blocks[b];
1721 if (bd.block_length <= 0) {
1722 av_log(ctx->avctx, AV_LOG_WARNING,
1723 "Invalid block length %u in channel data!\n",
1724 bd.block_length);
1725 continue;
1726 }
1727
1728 for (c = 0; c < channels; c++) {
1729 bd.const_block = ctx->const_block + c;
1730 bd.shift_lsbs = ctx->shift_lsbs + c;
1731 bd.opt_order = ctx->opt_order + c;
1732 bd.store_prev_samples = ctx->store_prev_samples + c;
1733 bd.use_ltp = ctx->use_ltp + c;
1734 bd.ltp_lag = ctx->ltp_lag + c;
1735 bd.ltp_gain = ctx->ltp_gain[c];
1736 bd.lpc_cof = ctx->lpc_cof[c];
1737 bd.quant_cof = ctx->quant_cof[c];
1738 bd.raw_samples = ctx->raw_samples[c] + offset;
1739 bd.raw_other = NULL;
1740
1741 if ((ret = read_block(ctx, &bd)) < 0)
1742 return ret;
1743 if ((ret = read_channel_data(ctx, ctx->chan_data[c], c)) < 0)
1744 return ret;
1745 }
1746
1747 for (c = 0; c < channels; c++) {
1748 ret = revert_channel_correlation(ctx, &bd, ctx->chan_data,
1749 reverted_channels, offset, c);
1750 if (ret < 0)
1751 return ret;
1752 }
1753 for (c = 0; c < channels; c++) {
1754 bd.const_block = ctx->const_block + c;
1755 bd.shift_lsbs = ctx->shift_lsbs + c;
1756 bd.opt_order = ctx->opt_order + c;
1757 bd.store_prev_samples = ctx->store_prev_samples + c;
1758 bd.use_ltp = ctx->use_ltp + c;
1759 bd.ltp_lag = ctx->ltp_lag + c;
1760 bd.ltp_gain = ctx->ltp_gain[c];
1761 bd.lpc_cof = ctx->lpc_cof[c];
1762 bd.quant_cof = ctx->quant_cof[c];
1763 bd.raw_samples = ctx->raw_samples[c] + offset;
1764
1765 if ((ret = decode_block(ctx, &bd)) < 0)
1766 return ret;
1767
1768 ctx->highest_decoded_channel = FFMAX(ctx->highest_decoded_channel, c);
1769 }
1770
1771 memset(reverted_channels, 0, channels * sizeof(*reverted_channels));
1772 offset += div_blocks[b];
1773 bd.ra_block = 0;
1774 }
1775
1776 // store carryover raw samples
1777 for (c = 0; c < channels; c++)
1778 memmove(ctx->raw_samples[c] - sconf->max_order,
1779 ctx->raw_samples[c] - sconf->max_order + sconf->frame_length,
1780 sizeof(*ctx->raw_samples[c]) * sconf->max_order);
1781 }
1782
1783 if (sconf->floating) {
1784 read_diff_float_data(ctx, ra_frame);
1785 }
1786
1787 if (get_bits_left(gb) < 0) {
1788 av_log(ctx->avctx, AV_LOG_ERROR, "Overread %d\n", -get_bits_left(gb));
1789 return AVERROR_INVALIDDATA;
1790 }
1791
1792 return 0;
1793 }
1794
1795
1796 /** Decode an ALS frame.
1797 */
decode_frame(AVCodecContext * avctx,AVFrame * frame,int * got_frame_ptr,AVPacket * avpkt)1798 static int decode_frame(AVCodecContext *avctx, AVFrame *frame,
1799 int *got_frame_ptr, AVPacket *avpkt)
1800 {
1801 ALSDecContext *ctx = avctx->priv_data;
1802 ALSSpecificConfig *sconf = &ctx->sconf;
1803 const uint8_t *buffer = avpkt->data;
1804 int buffer_size = avpkt->size;
1805 int invalid_frame, ret;
1806 int channels = avctx->ch_layout.nb_channels;
1807 unsigned int c, sample, ra_frame, bytes_read, shift;
1808
1809 if ((ret = init_get_bits8(&ctx->gb, buffer, buffer_size)) < 0)
1810 return ret;
1811
1812 // In the case that the distance between random access frames is set to zero
1813 // (sconf->ra_distance == 0) no frame is treated as a random access frame.
1814 // For the first frame, if prediction is used, all samples used from the
1815 // previous frame are assumed to be zero.
1816 ra_frame = sconf->ra_distance && !(ctx->frame_id % sconf->ra_distance);
1817
1818 // the last frame to decode might have a different length
1819 if (sconf->samples != 0xFFFFFFFF)
1820 ctx->cur_frame_length = FFMIN(sconf->samples - ctx->frame_id * (uint64_t) sconf->frame_length,
1821 sconf->frame_length);
1822 else
1823 ctx->cur_frame_length = sconf->frame_length;
1824
1825 ctx->highest_decoded_channel = -1;
1826 // decode the frame data
1827 if ((invalid_frame = read_frame_data(ctx, ra_frame)) < 0)
1828 av_log(ctx->avctx, AV_LOG_WARNING,
1829 "Reading frame data failed. Skipping RA unit.\n");
1830
1831 if (ctx->highest_decoded_channel == -1) {
1832 av_log(ctx->avctx, AV_LOG_WARNING,
1833 "No channel data decoded.\n");
1834 return AVERROR_INVALIDDATA;
1835 }
1836
1837 ctx->frame_id++;
1838
1839 /* get output buffer */
1840 frame->nb_samples = ctx->cur_frame_length;
1841 if ((ret = ff_get_buffer(avctx, frame, 0)) < 0)
1842 return ret;
1843
1844 // transform decoded frame into output format
1845 #define INTERLEAVE_OUTPUT(bps) \
1846 { \
1847 int##bps##_t *dest = (int##bps##_t*)frame->data[0]; \
1848 int32_t *raw_samples = ctx->raw_samples[0]; \
1849 int raw_step = channels > 1 ? ctx->raw_samples[1] - raw_samples : 1; \
1850 shift = bps - ctx->avctx->bits_per_raw_sample; \
1851 if (!ctx->cs_switch) { \
1852 for (sample = 0; sample < ctx->cur_frame_length; sample++) \
1853 for (c = 0; c < channels; c++) \
1854 *dest++ = raw_samples[c*raw_step + sample] * (1U << shift); \
1855 } else { \
1856 for (sample = 0; sample < ctx->cur_frame_length; sample++) \
1857 for (c = 0; c < channels; c++) \
1858 *dest++ = raw_samples[sconf->chan_pos[c]*raw_step + sample] * (1U << shift);\
1859 } \
1860 }
1861
1862 if (ctx->avctx->bits_per_raw_sample <= 16) {
1863 INTERLEAVE_OUTPUT(16)
1864 } else {
1865 INTERLEAVE_OUTPUT(32)
1866 }
1867
1868 // update CRC
1869 if (sconf->crc_enabled && (avctx->err_recognition & (AV_EF_CRCCHECK|AV_EF_CAREFUL))) {
1870 int swap = HAVE_BIGENDIAN != sconf->msb_first;
1871
1872 if (ctx->avctx->bits_per_raw_sample == 24) {
1873 int32_t *src = (int32_t *)frame->data[0];
1874
1875 for (sample = 0;
1876 sample < ctx->cur_frame_length * channels;
1877 sample++) {
1878 int32_t v;
1879
1880 if (swap)
1881 v = av_bswap32(src[sample]);
1882 else
1883 v = src[sample];
1884 if (!HAVE_BIGENDIAN)
1885 v >>= 8;
1886
1887 ctx->crc = av_crc(ctx->crc_table, ctx->crc, (uint8_t*)(&v), 3);
1888 }
1889 } else {
1890 uint8_t *crc_source;
1891
1892 if (swap) {
1893 if (ctx->avctx->bits_per_raw_sample <= 16) {
1894 int16_t *src = (int16_t*) frame->data[0];
1895 int16_t *dest = (int16_t*) ctx->crc_buffer;
1896 for (sample = 0;
1897 sample < ctx->cur_frame_length * channels;
1898 sample++)
1899 *dest++ = av_bswap16(src[sample]);
1900 } else {
1901 ctx->bdsp.bswap_buf((uint32_t *) ctx->crc_buffer,
1902 (uint32_t *) frame->data[0],
1903 ctx->cur_frame_length * channels);
1904 }
1905 crc_source = ctx->crc_buffer;
1906 } else {
1907 crc_source = frame->data[0];
1908 }
1909
1910 ctx->crc = av_crc(ctx->crc_table, ctx->crc, crc_source,
1911 ctx->cur_frame_length * channels *
1912 av_get_bytes_per_sample(avctx->sample_fmt));
1913 }
1914
1915
1916 // check CRC sums if this is the last frame
1917 if (ctx->cur_frame_length != sconf->frame_length &&
1918 ctx->crc_org != ctx->crc) {
1919 av_log(avctx, AV_LOG_ERROR, "CRC error.\n");
1920 if (avctx->err_recognition & AV_EF_EXPLODE)
1921 return AVERROR_INVALIDDATA;
1922 }
1923 }
1924
1925 *got_frame_ptr = 1;
1926
1927 bytes_read = invalid_frame ? buffer_size :
1928 (get_bits_count(&ctx->gb) + 7) >> 3;
1929
1930 return bytes_read;
1931 }
1932
1933
1934 /** Uninitialize the ALS decoder.
1935 */
decode_end(AVCodecContext * avctx)1936 static av_cold int decode_end(AVCodecContext *avctx)
1937 {
1938 ALSDecContext *ctx = avctx->priv_data;
1939 int i;
1940
1941 av_freep(&ctx->sconf.chan_pos);
1942
1943 ff_bgmc_end(&ctx->bgmc_lut, &ctx->bgmc_lut_status);
1944
1945 av_freep(&ctx->const_block);
1946 av_freep(&ctx->shift_lsbs);
1947 av_freep(&ctx->opt_order);
1948 av_freep(&ctx->store_prev_samples);
1949 av_freep(&ctx->use_ltp);
1950 av_freep(&ctx->ltp_lag);
1951 av_freep(&ctx->ltp_gain);
1952 av_freep(&ctx->ltp_gain_buffer);
1953 av_freep(&ctx->quant_cof);
1954 av_freep(&ctx->lpc_cof);
1955 av_freep(&ctx->quant_cof_buffer);
1956 av_freep(&ctx->lpc_cof_buffer);
1957 av_freep(&ctx->lpc_cof_reversed_buffer);
1958 av_freep(&ctx->prev_raw_samples);
1959 av_freep(&ctx->raw_samples);
1960 av_freep(&ctx->raw_buffer);
1961 av_freep(&ctx->chan_data);
1962 av_freep(&ctx->chan_data_buffer);
1963 av_freep(&ctx->reverted_channels);
1964 av_freep(&ctx->crc_buffer);
1965 if (ctx->mlz) {
1966 av_freep(&ctx->mlz->dict);
1967 av_freep(&ctx->mlz);
1968 }
1969 av_freep(&ctx->acf);
1970 av_freep(&ctx->last_acf_mantissa);
1971 av_freep(&ctx->shift_value);
1972 av_freep(&ctx->last_shift_value);
1973 if (ctx->raw_mantissa) {
1974 for (i = 0; i < avctx->ch_layout.nb_channels; i++) {
1975 av_freep(&ctx->raw_mantissa[i]);
1976 }
1977 av_freep(&ctx->raw_mantissa);
1978 }
1979 av_freep(&ctx->larray);
1980 av_freep(&ctx->nbits);
1981
1982 return 0;
1983 }
1984
1985
1986 /** Initialize the ALS decoder.
1987 */
decode_init(AVCodecContext * avctx)1988 static av_cold int decode_init(AVCodecContext *avctx)
1989 {
1990 unsigned int c;
1991 unsigned int channel_size;
1992 int num_buffers, ret;
1993 int channels;
1994 ALSDecContext *ctx = avctx->priv_data;
1995 ALSSpecificConfig *sconf = &ctx->sconf;
1996 ctx->avctx = avctx;
1997
1998 if (!avctx->extradata) {
1999 av_log(avctx, AV_LOG_ERROR, "Missing required ALS extradata.\n");
2000 return AVERROR_INVALIDDATA;
2001 }
2002
2003 if ((ret = read_specific_config(ctx)) < 0) {
2004 av_log(avctx, AV_LOG_ERROR, "Reading ALSSpecificConfig failed.\n");
2005 return ret;
2006 }
2007 channels = avctx->ch_layout.nb_channels;
2008
2009 if ((ret = check_specific_config(ctx)) < 0) {
2010 return ret;
2011 }
2012
2013 if (sconf->bgmc) {
2014 ret = ff_bgmc_init(avctx, &ctx->bgmc_lut, &ctx->bgmc_lut_status);
2015 if (ret < 0)
2016 return ret;
2017 }
2018 if (sconf->floating) {
2019 avctx->sample_fmt = AV_SAMPLE_FMT_FLT;
2020 avctx->bits_per_raw_sample = 32;
2021 } else {
2022 avctx->sample_fmt = sconf->resolution > 1
2023 ? AV_SAMPLE_FMT_S32 : AV_SAMPLE_FMT_S16;
2024 avctx->bits_per_raw_sample = (sconf->resolution + 1) * 8;
2025 if (avctx->bits_per_raw_sample > 32) {
2026 av_log(avctx, AV_LOG_ERROR, "Bits per raw sample %d larger than 32.\n",
2027 avctx->bits_per_raw_sample);
2028 return AVERROR_INVALIDDATA;
2029 }
2030 }
2031
2032 // set maximum Rice parameter for progressive decoding based on resolution
2033 // This is not specified in 14496-3 but actually done by the reference
2034 // codec RM22 revision 2.
2035 ctx->s_max = sconf->resolution > 1 ? 31 : 15;
2036
2037 // set lag value for long-term prediction
2038 ctx->ltp_lag_length = 8 + (avctx->sample_rate >= 96000) +
2039 (avctx->sample_rate >= 192000);
2040
2041 // allocate quantized parcor coefficient buffer
2042 num_buffers = sconf->mc_coding ? channels : 1;
2043 if (num_buffers * (uint64_t)num_buffers > INT_MAX) // protect chan_data_buffer allocation
2044 return AVERROR_INVALIDDATA;
2045
2046 ctx->quant_cof = av_malloc_array(num_buffers, sizeof(*ctx->quant_cof));
2047 ctx->lpc_cof = av_malloc_array(num_buffers, sizeof(*ctx->lpc_cof));
2048 ctx->quant_cof_buffer = av_malloc_array(num_buffers * sconf->max_order,
2049 sizeof(*ctx->quant_cof_buffer));
2050 ctx->lpc_cof_buffer = av_malloc_array(num_buffers * sconf->max_order,
2051 sizeof(*ctx->lpc_cof_buffer));
2052 ctx->lpc_cof_reversed_buffer = av_malloc_array(sconf->max_order,
2053 sizeof(*ctx->lpc_cof_buffer));
2054
2055 if (!ctx->quant_cof || !ctx->lpc_cof ||
2056 !ctx->quant_cof_buffer || !ctx->lpc_cof_buffer ||
2057 !ctx->lpc_cof_reversed_buffer) {
2058 av_log(avctx, AV_LOG_ERROR, "Allocating buffer memory failed.\n");
2059 return AVERROR(ENOMEM);
2060 }
2061
2062 // assign quantized parcor coefficient buffers
2063 for (c = 0; c < num_buffers; c++) {
2064 ctx->quant_cof[c] = ctx->quant_cof_buffer + c * sconf->max_order;
2065 ctx->lpc_cof[c] = ctx->lpc_cof_buffer + c * sconf->max_order;
2066 }
2067
2068 // allocate and assign lag and gain data buffer for ltp mode
2069 ctx->const_block = av_malloc_array(num_buffers, sizeof(*ctx->const_block));
2070 ctx->shift_lsbs = av_malloc_array(num_buffers, sizeof(*ctx->shift_lsbs));
2071 ctx->opt_order = av_malloc_array(num_buffers, sizeof(*ctx->opt_order));
2072 ctx->store_prev_samples = av_malloc_array(num_buffers, sizeof(*ctx->store_prev_samples));
2073 ctx->use_ltp = av_calloc(num_buffers, sizeof(*ctx->use_ltp));
2074 ctx->ltp_lag = av_malloc_array(num_buffers, sizeof(*ctx->ltp_lag));
2075 ctx->ltp_gain = av_malloc_array(num_buffers, sizeof(*ctx->ltp_gain));
2076 ctx->ltp_gain_buffer = av_malloc_array(num_buffers * 5, sizeof(*ctx->ltp_gain_buffer));
2077
2078 if (!ctx->const_block || !ctx->shift_lsbs ||
2079 !ctx->opt_order || !ctx->store_prev_samples ||
2080 !ctx->use_ltp || !ctx->ltp_lag ||
2081 !ctx->ltp_gain || !ctx->ltp_gain_buffer) {
2082 av_log(avctx, AV_LOG_ERROR, "Allocating buffer memory failed.\n");
2083 return AVERROR(ENOMEM);
2084 }
2085
2086 for (c = 0; c < num_buffers; c++)
2087 ctx->ltp_gain[c] = ctx->ltp_gain_buffer + c * 5;
2088
2089 // allocate and assign channel data buffer for mcc mode
2090 if (sconf->mc_coding) {
2091 ctx->chan_data_buffer = av_calloc(num_buffers * num_buffers,
2092 sizeof(*ctx->chan_data_buffer));
2093 ctx->chan_data = av_calloc(num_buffers, sizeof(*ctx->chan_data));
2094 ctx->reverted_channels = av_malloc_array(num_buffers,
2095 sizeof(*ctx->reverted_channels));
2096
2097 if (!ctx->chan_data_buffer || !ctx->chan_data || !ctx->reverted_channels) {
2098 av_log(avctx, AV_LOG_ERROR, "Allocating buffer memory failed.\n");
2099 return AVERROR(ENOMEM);
2100 }
2101
2102 for (c = 0; c < num_buffers; c++)
2103 ctx->chan_data[c] = ctx->chan_data_buffer + c * num_buffers;
2104 } else {
2105 ctx->chan_data = NULL;
2106 ctx->chan_data_buffer = NULL;
2107 ctx->reverted_channels = NULL;
2108 }
2109
2110 if (sconf->floating) {
2111 ctx->acf = av_malloc_array(channels, sizeof(*ctx->acf));
2112 ctx->shift_value = av_malloc_array(channels, sizeof(*ctx->shift_value));
2113 ctx->last_shift_value = av_malloc_array(channels, sizeof(*ctx->last_shift_value));
2114 ctx->last_acf_mantissa = av_malloc_array(channels, sizeof(*ctx->last_acf_mantissa));
2115 ctx->raw_mantissa = av_calloc(channels, sizeof(*ctx->raw_mantissa));
2116
2117 ctx->larray = av_malloc_array(ctx->cur_frame_length * 4, sizeof(*ctx->larray));
2118 ctx->nbits = av_malloc_array(ctx->cur_frame_length, sizeof(*ctx->nbits));
2119 ctx->mlz = av_mallocz(sizeof(*ctx->mlz));
2120
2121 if (!ctx->mlz || !ctx->acf || !ctx->shift_value || !ctx->last_shift_value
2122 || !ctx->last_acf_mantissa || !ctx->raw_mantissa) {
2123 av_log(avctx, AV_LOG_ERROR, "Allocating buffer memory failed.\n");
2124 return AVERROR(ENOMEM);
2125 }
2126
2127 ret = ff_mlz_init_dict(avctx, ctx->mlz);
2128 if (ret < 0)
2129 return ret;
2130 ff_mlz_flush_dict(ctx->mlz);
2131
2132 for (c = 0; c < channels; ++c) {
2133 ctx->raw_mantissa[c] = av_calloc(ctx->cur_frame_length, sizeof(**ctx->raw_mantissa));
2134 }
2135 }
2136
2137 channel_size = sconf->frame_length + sconf->max_order;
2138
2139 // allocate previous raw sample buffer
2140 ctx->prev_raw_samples = av_malloc_array(sconf->max_order, sizeof(*ctx->prev_raw_samples));
2141 ctx->raw_buffer = av_calloc(channels * channel_size, sizeof(*ctx->raw_buffer));
2142 ctx->raw_samples = av_malloc_array(channels, sizeof(*ctx->raw_samples));
2143 if (!ctx->prev_raw_samples || !ctx->raw_buffer|| !ctx->raw_samples) {
2144 av_log(avctx, AV_LOG_ERROR, "Allocating buffer memory failed.\n");
2145 return AVERROR(ENOMEM);
2146 }
2147
2148 // assign raw samples buffers
2149 ctx->raw_samples[0] = ctx->raw_buffer + sconf->max_order;
2150 for (c = 1; c < channels; c++)
2151 ctx->raw_samples[c] = ctx->raw_samples[c - 1] + channel_size;
2152
2153 // allocate crc buffer
2154 if (HAVE_BIGENDIAN != sconf->msb_first && sconf->crc_enabled &&
2155 (avctx->err_recognition & (AV_EF_CRCCHECK|AV_EF_CAREFUL))) {
2156 ctx->crc_buffer = av_malloc_array(ctx->cur_frame_length *
2157 channels *
2158 av_get_bytes_per_sample(avctx->sample_fmt),
2159 sizeof(*ctx->crc_buffer));
2160 if (!ctx->crc_buffer) {
2161 av_log(avctx, AV_LOG_ERROR, "Allocating buffer memory failed.\n");
2162 return AVERROR(ENOMEM);
2163 }
2164 }
2165
2166 ff_bswapdsp_init(&ctx->bdsp);
2167
2168 return 0;
2169 }
2170
2171
2172 /** Flush (reset) the frame ID after seeking.
2173 */
flush(AVCodecContext * avctx)2174 static av_cold void flush(AVCodecContext *avctx)
2175 {
2176 ALSDecContext *ctx = avctx->priv_data;
2177
2178 ctx->frame_id = 0;
2179 }
2180
2181
2182 const FFCodec ff_als_decoder = {
2183 .p.name = "als",
2184 .p.long_name = NULL_IF_CONFIG_SMALL("MPEG-4 Audio Lossless Coding (ALS)"),
2185 .p.type = AVMEDIA_TYPE_AUDIO,
2186 .p.id = AV_CODEC_ID_MP4ALS,
2187 .priv_data_size = sizeof(ALSDecContext),
2188 .init = decode_init,
2189 .close = decode_end,
2190 FF_CODEC_DECODE_CB(decode_frame),
2191 .flush = flush,
2192 .p.capabilities = AV_CODEC_CAP_SUBFRAMES | AV_CODEC_CAP_DR1 | AV_CODEC_CAP_CHANNEL_CONF,
2193 .caps_internal = FF_CODEC_CAP_INIT_THREADSAFE | FF_CODEC_CAP_INIT_CLEANUP,
2194 };
2195