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