path: root/libavcodec/alsdec.c (plain)
blob: d95e30d10d3f2f260b710446a5fa1bbcc13139b4

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 "bytestream.h"
35	#include "bgmc.h"
36	#include "bswapdsp.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	} 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
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	*/
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_config(&m4ac, avctx->extradata,
307	avctx->extradata_size * 8, 1);
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	ctx->cur_frame_length = sconf->frame_length;
353
354	// read channel config
355	if (sconf->chan_config)
356	sconf->chan_config_info = get_bits(&gb, 16);
357	// TODO: use this to set avctx->channel_layout
358
359
360	// read channel sorting
361	if (sconf->chan_sort && avctx->channels > 1) {
362	int chan_pos_bits = av_ceil_log2(avctx->channels);
363	int bits_needed = avctx->channels * chan_pos_bits + 7;
364	if (get_bits_left(&gb) < bits_needed)
365	return AVERROR_INVALIDDATA;
366
367	if (!(sconf->chan_pos = av_malloc_array(avctx->channels, sizeof(*sconf->chan_pos))))
368	return AVERROR(ENOMEM);
369
370	ctx->cs_switch = 1;
371
372	for (i = 0; i < avctx->channels; i++) {
373	sconf->chan_pos[i] = -1;
374	}
375
376	for (i = 0; i < avctx->channels; i++) {
377	int idx;
378
379	idx = get_bits(&gb, chan_pos_bits);
380	if (idx >= avctx->channels || sconf->chan_pos[idx] != -1) {
381	av_log(avctx, AV_LOG_WARNING, "Invalid channel reordering.\n");
382	ctx->cs_switch = 0;
383	break;
384	}
385	sconf->chan_pos[idx] = i;
386	}
387
388	align_get_bits(&gb);
389	}
390
391
392	// read fixed header and trailer sizes,
393	// if size = 0xFFFFFFFF then there is no data field!
394	if (get_bits_left(&gb) < 64)
395	return AVERROR_INVALIDDATA;
396
397	header_size = get_bits_long(&gb, 32);
398	trailer_size = get_bits_long(&gb, 32);
399	if (header_size == 0xFFFFFFFF)
400	header_size = 0;
401	if (trailer_size == 0xFFFFFFFF)
402	trailer_size = 0;
403
404	ht_size = ((int64_t)(header_size) + (int64_t)(trailer_size)) << 3;
405
406
407	// skip the header and trailer data
408	if (get_bits_left(&gb) < ht_size)
409	return AVERROR_INVALIDDATA;
410
411	if (ht_size > INT32_MAX)
412	return AVERROR_PATCHWELCOME;
413
414	skip_bits_long(&gb, ht_size);
415
416
417	// initialize CRC calculation
418	if (sconf->crc_enabled) {
419	if (get_bits_left(&gb) < 32)
420	return AVERROR_INVALIDDATA;
421
422	if (avctx->err_recognition & (AV_EF_CRCCHECK|AV_EF_CAREFUL)) {
423	ctx->crc_table = av_crc_get_table(AV_CRC_32_IEEE_LE);
424	ctx->crc = 0xFFFFFFFF;
425	ctx->crc_org = ~get_bits_long(&gb, 32);
426	} else
427	skip_bits_long(&gb, 32);
428	}
429
430
431	// no need to read the rest of ALSSpecificConfig (ra_unit_size & aux data)
432
433	dprint_specific_config(ctx);
434
435	return 0;
436	}
437
438
439	/** Check the ALSSpecificConfig for unsupported features.
440	*/
441	static int check_specific_config(ALSDecContext *ctx)
442	{
443	ALSSpecificConfig *sconf = &ctx->sconf;
444	int error = 0;
445
446	// report unsupported feature and set error value
447	#define MISSING_ERR(cond, str, errval) \
448	{ \
449	if (cond) { \
450	avpriv_report_missing_feature(ctx->avctx, \
451	str); \
452	error = errval; \
453	} \
454	}
455
456	MISSING_ERR(sconf->rlslms, "Adaptive RLS-LMS prediction", AVERROR_PATCHWELCOME);
457
458	return error;
459	}
460
461
462	/** Parse the bs_info field to extract the block partitioning used in
463	* block switching mode, refer to ISO/IEC 14496-3, section 11.6.2.
464	*/
465	static void parse_bs_info(const uint32_t bs_info, unsigned int n,
466	unsigned int div, unsigned int **div_blocks,
467	unsigned int *num_blocks)
468	{
469	if (n < 31 && ((bs_info << n) & 0x40000000)) {
470	// if the level is valid and the investigated bit n is set
471	// then recursively check both children at bits (2n+1) and (2n+2)
472	n *= 2;
473	div += 1;
474	parse_bs_info(bs_info, n + 1, div, div_blocks, num_blocks);
475	parse_bs_info(bs_info, n + 2, div, div_blocks, num_blocks);
476	} else {
477	// else the bit is not set or the last level has been reached
478	// (bit implicitly not set)
479	**div_blocks = div;
480	(*div_blocks)++;
481	(*num_blocks)++;
482	}
483	}
484
485
486	/** Read and decode a Rice codeword.
487	*/
488	static int32_t decode_rice(GetBitContext *gb, unsigned int k)
489	{
490	int max = get_bits_left(gb) - k;
491	int q = get_unary(gb, 0, max);
492	int r = k ? get_bits1(gb) : !(q & 1);
493
494	if (k > 1) {
495	q <<= (k - 1);
496	q += get_bits_long(gb, k - 1);
497	} else if (!k) {
498	q >>= 1;
499	}
500	return r ? q : ~q;
501	}
502
503
504	/** Convert PARCOR coefficient k to direct filter coefficient.
505	*/
506	static void parcor_to_lpc(unsigned int k, const int32_t *par, int32_t *cof)
507	{
508	int i, j;
509
510	for (i = 0, j = k - 1; i < j; i++, j--) {
511	int tmp1 = ((MUL64(par[k], cof[j]) + (1 << 19)) >> 20);
512	cof[j] += ((MUL64(par[k], cof[i]) + (1 << 19)) >> 20);
513	cof[i] += tmp1;
514	}
515	if (i == j)
516	cof[i] += ((MUL64(par[k], cof[j]) + (1 << 19)) >> 20);
517
518	cof[k] = par[k];
519	}
520
521
522	/** Read block switching field if necessary and set actual block sizes.
523	* Also assure that the block sizes of the last frame correspond to the
524	* actual number of samples.
525	*/
526	static void get_block_sizes(ALSDecContext *ctx, unsigned int *div_blocks,
527	uint32_t *bs_info)
528	{
529	ALSSpecificConfig *sconf = &ctx->sconf;
530	GetBitContext *gb = &ctx->gb;
531	unsigned int *ptr_div_blocks = div_blocks;
532	unsigned int b;
533
534	if (sconf->block_switching) {
535	unsigned int bs_info_len = 1 << (sconf->block_switching + 2);
536	*bs_info = get_bits_long(gb, bs_info_len);
537	*bs_info <<= (32 - bs_info_len);
538	}
539
540	ctx->num_blocks = 0;
541	parse_bs_info(*bs_info, 0, 0, &ptr_div_blocks, &ctx->num_blocks);
542
543	// The last frame may have an overdetermined block structure given in
544	// the bitstream. In that case the defined block structure would need
545	// more samples than available to be consistent.
546	// The block structure is actually used but the block sizes are adapted
547	// to fit the actual number of available samples.
548	// Example: 5 samples, 2nd level block sizes: 2 2 2 2.
549	// This results in the actual block sizes: 2 2 1 0.
550	// This is not specified in 14496-3 but actually done by the reference
551	// codec RM22 revision 2.
552	// This appears to happen in case of an odd number of samples in the last
553	// frame which is actually not allowed by the block length switching part
554	// of 14496-3.
555	// The ALS conformance files feature an odd number of samples in the last
556	// frame.
557
558	for (b = 0; b < ctx->num_blocks; b++)
559	div_blocks[b] = ctx->sconf.frame_length >> div_blocks[b];
560
561	if (ctx->cur_frame_length != ctx->sconf.frame_length) {
562	unsigned int remaining = ctx->cur_frame_length;
563
564	for (b = 0; b < ctx->num_blocks; b++) {
565	if (remaining <= div_blocks[b]) {
566	div_blocks[b] = remaining;
567	ctx->num_blocks = b + 1;
568	break;
569	}
570
571	remaining -= div_blocks[b];
572	}
573	}
574	}
575
576
577	/** Read the block data for a constant block
578	*/
579	static int read_const_block_data(ALSDecContext *ctx, ALSBlockData *bd)
580	{
581	ALSSpecificConfig *sconf = &ctx->sconf;
582	AVCodecContext *avctx = ctx->avctx;
583	GetBitContext *gb = &ctx->gb;
584
585	if (bd->block_length <= 0)
586	return AVERROR_INVALIDDATA;
587
588	*bd->raw_samples = 0;
589	*bd->const_block = get_bits1(gb); // 1 = constant value, 0 = zero block (silence)
590	bd->js_blocks = get_bits1(gb);
591
592	// skip 5 reserved bits
593	skip_bits(gb, 5);
594
595	if (*bd->const_block) {
596	unsigned int const_val_bits = sconf->floating ? 24 : avctx->bits_per_raw_sample;
597	*bd->raw_samples = get_sbits_long(gb, const_val_bits);
598	}
599
600	// ensure constant block decoding by reusing this field
601	*bd->const_block = 1;
602
603	return 0;
604	}
605
606
607	/** Decode the block data for a constant block
608	*/
609	static void decode_const_block_data(ALSDecContext *ctx, ALSBlockData *bd)
610	{
611	int smp = bd->block_length - 1;
612	int32_t val = *bd->raw_samples;
613	int32_t *dst = bd->raw_samples + 1;
614
615	// write raw samples into buffer
616	for (; smp; smp--)
617	*dst++ = val;
618	}
619
620
621	/** Read the block data for a non-constant block
622	*/
623	static int read_var_block_data(ALSDecContext *ctx, ALSBlockData *bd)
624	{
625	ALSSpecificConfig *sconf = &ctx->sconf;
626	AVCodecContext *avctx = ctx->avctx;
627	GetBitContext *gb = &ctx->gb;
628	unsigned int k;
629	unsigned int s[8];
630	unsigned int sx[8];
631	unsigned int sub_blocks, log2_sub_blocks, sb_length;
632	unsigned int start = 0;
633	unsigned int opt_order;
634	int sb;
635	int32_t *quant_cof = bd->quant_cof;
636	int32_t *current_res;
637
638
639	// ensure variable block decoding by reusing this field
640	*bd->const_block = 0;
641
642	*bd->opt_order = 1;
643	bd->js_blocks = get_bits1(gb);
644
645	opt_order = *bd->opt_order;
646
647	// determine the number of subblocks for entropy decoding
648	if (!sconf->bgmc && !sconf->sb_part) {
649	log2_sub_blocks = 0;
650	} else {
651	if (sconf->bgmc && sconf->sb_part)
652	log2_sub_blocks = get_bits(gb, 2);
653	else
654	log2_sub_blocks = 2 * get_bits1(gb);
655	}
656
657	sub_blocks = 1 << log2_sub_blocks;
658
659	// do not continue in case of a damaged stream since
660	// block_length must be evenly divisible by sub_blocks
661	if (bd->block_length & (sub_blocks - 1)) {
662	av_log(avctx, AV_LOG_WARNING,
663	"Block length is not evenly divisible by the number of subblocks.\n");
664	return AVERROR_INVALIDDATA;
665	}
666
667	sb_length = bd->block_length >> log2_sub_blocks;
668
669	if (sconf->bgmc) {
670	s[0] = get_bits(gb, 8 + (sconf->resolution > 1));
671	for (k = 1; k < sub_blocks; k++)
672	s[k] = s[k - 1] + decode_rice(gb, 2);
673
674	for (k = 0; k < sub_blocks; k++) {
675	sx[k] = s[k] & 0x0F;
676	s [k] >>= 4;
677	}
678	} else {
679	s[0] = get_bits(gb, 4 + (sconf->resolution > 1));
680	for (k = 1; k < sub_blocks; k++)
681	s[k] = s[k - 1] + decode_rice(gb, 0);
682	}
683	for (k = 1; k < sub_blocks; k++)
684	if (s[k] > 32) {
685	av_log(avctx, AV_LOG_ERROR, "k invalid for rice code.\n");
686	return AVERROR_INVALIDDATA;
687	}
688
689	if (get_bits1(gb))
690	*bd->shift_lsbs = get_bits(gb, 4) + 1;
691
692	*bd->store_prev_samples = (bd->js_blocks && bd->raw_other) || *bd->shift_lsbs;
693
694
695	if (!sconf->rlslms) {
696	if (sconf->adapt_order && sconf->max_order) {
697	int opt_order_length = av_ceil_log2(av_clip((bd->block_length >> 3) - 1,
698	2, sconf->max_order + 1));
699	*bd->opt_order = get_bits(gb, opt_order_length);
700	if (*bd->opt_order > sconf->max_order) {
701	*bd->opt_order = sconf->max_order;
702	av_log(avctx, AV_LOG_ERROR, "Predictor order too large.\n");
703	return AVERROR_INVALIDDATA;
704	}
705	} else {
706	*bd->opt_order = sconf->max_order;
707	}
708	if (*bd->opt_order > bd->block_length) {
709	*bd->opt_order = bd->block_length;
710	av_log(avctx, AV_LOG_ERROR, "Predictor order too large.\n");
711	return AVERROR_INVALIDDATA;
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] << 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) << 3;
777	bd->ltp_gain[1] = decode_rice(gb, 2) << 3;
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) << 3;
789	bd->ltp_gain[4] = decode_rice(gb, 1) << 3;
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	if (opt_order)
799	bd->raw_samples[0] = decode_rice(gb, avctx->bits_per_raw_sample - 4);
800	if (opt_order > 1)
801	bd->raw_samples[1] = decode_rice(gb, FFMIN(s[0] + 3, ctx->s_max));
802	if (opt_order > 2)
803	bd->raw_samples[2] = decode_rice(gb, FFMIN(s[0] + 1, ctx->s_max));
804
805	start = FFMIN(opt_order, 3);
806	}
807
808	// read all residuals
809	if (sconf->bgmc) {
810	int delta[8];
811	unsigned int k [8];
812	unsigned int b = av_clip((av_ceil_log2(bd->block_length) - 3) >> 1, 0, 5);
813
814	// read most significant bits
815	unsigned int high;
816	unsigned int low;
817	unsigned int value;
818
819	ff_bgmc_decode_init(gb, &high, &low, &value);
820
821	current_res = bd->raw_samples + start;
822
823	for (sb = 0; sb < sub_blocks; sb++) {
824	unsigned int sb_len = sb_length - (sb ? 0 : start);
825
826	k [sb] = s[sb] > b ? s[sb] - b : 0;
827	delta[sb] = 5 - s[sb] + k[sb];
828
829	ff_bgmc_decode(gb, sb_len, current_res,
830	delta[sb], sx[sb], &high, &low, &value, ctx->bgmc_lut, ctx->bgmc_lut_status);
831
832	current_res += sb_len;
833	}
834
835	ff_bgmc_decode_end(gb);
836
837
838	// read least significant bits and tails
839	current_res = bd->raw_samples + start;
840
841	for (sb = 0; sb < sub_blocks; sb++, start = 0) {
842	unsigned int cur_tail_code = tail_code[sx[sb]][delta[sb]];
843	unsigned int cur_k = k[sb];
844	unsigned int cur_s = s[sb];
845
846	for (; start < sb_length; start++) {
847	int32_t res = *current_res;
848
849	if (res == cur_tail_code) {
850	unsigned int max_msb = (2 + (sx[sb] > 2) + (sx[sb] > 10))
851	<< (5 - delta[sb]);
852
853	res = decode_rice(gb, cur_s);
854
855	if (res >= 0) {
856	res += (max_msb ) << cur_k;
857	} else {
858	res -= (max_msb - 1) << cur_k;
859	}
860	} else {
861	if (res > cur_tail_code)
862	res--;
863
864	if (res & 1)
865	res = -res;
866
867	res >>= 1;
868
869	if (cur_k) {
870	res <<= cur_k;
871	res |= get_bits_long(gb, cur_k);
872	}
873	}
874
875	*current_res++ = res;
876	}
877	}
878	} else {
879	current_res = bd->raw_samples + start;
880
881	for (sb = 0; sb < sub_blocks; sb++, start = 0)
882	for (; start < sb_length; start++)
883	*current_res++ = decode_rice(gb, s[sb]);
884	}
885
886	return 0;
887	}
888
889
890	/** Decode the block data for a non-constant block
891	*/
892	static int decode_var_block_data(ALSDecContext *ctx, ALSBlockData *bd)
893	{
894	ALSSpecificConfig *sconf = &ctx->sconf;
895	unsigned int block_length = bd->block_length;
896	unsigned int smp = 0;
897	unsigned int k;
898	int opt_order = *bd->opt_order;
899	int sb;
900	int64_t y;
901	int32_t *quant_cof = bd->quant_cof;
902	int32_t *lpc_cof = bd->lpc_cof;
903	int32_t *raw_samples = bd->raw_samples;
904	int32_t *raw_samples_end = bd->raw_samples + bd->block_length;
905	int32_t *lpc_cof_reversed = ctx->lpc_cof_reversed_buffer;
906
907	// reverse long-term prediction
908	if (*bd->use_ltp) {
909	int ltp_smp;
910
911	for (ltp_smp = FFMAX(*bd->ltp_lag - 2, 0); ltp_smp < block_length; ltp_smp++) {
912	int center = ltp_smp - *bd->ltp_lag;
913	int begin = FFMAX(0, center - 2);
914	int end = center + 3;
915	int tab = 5 - (end - begin);
916	int base;
917
918	y = 1 << 6;
919
920	for (base = begin; base < end; base++, tab++)
921	y += MUL64(bd->ltp_gain[tab], raw_samples[base]);
922
923	raw_samples[ltp_smp] += y >> 7;
924	}
925	}
926
927	// reconstruct all samples from residuals
928	if (bd->ra_block) {
929	for (smp = 0; smp < opt_order; smp++) {
930	y = 1 << 19;
931
932	for (sb = 0; sb < smp; sb++)
933	y += MUL64(lpc_cof[sb], raw_samples[-(sb + 1)]);
934
935	*raw_samples++ -= y >> 20;
936	parcor_to_lpc(smp, quant_cof, lpc_cof);
937	}
938	} else {
939	for (k = 0; k < opt_order; k++)
940	parcor_to_lpc(k, quant_cof, lpc_cof);
941
942	// store previous samples in case that they have to be altered
943	if (*bd->store_prev_samples)
944	memcpy(bd->prev_raw_samples, raw_samples - sconf->max_order,
945	sizeof(*bd->prev_raw_samples) * sconf->max_order);
946
947	// reconstruct difference signal for prediction (joint-stereo)
948	if (bd->js_blocks && bd->raw_other) {
949	int32_t *left, *right;
950
951	if (bd->raw_other > raw_samples) { // D = R - L
952	left = raw_samples;
953	right = bd->raw_other;
954	} else { // D = R - L
955	left = bd->raw_other;
956	right = raw_samples;
957	}
958
959	for (sb = -1; sb >= -sconf->max_order; sb--)
960	raw_samples[sb] = right[sb] - left[sb];
961	}
962
963	// reconstruct shifted signal
964	if (*bd->shift_lsbs)
965	for (sb = -1; sb >= -sconf->max_order; sb--)
966	raw_samples[sb] >>= *bd->shift_lsbs;
967	}
968
969	// reverse linear prediction coefficients for efficiency
970	lpc_cof = lpc_cof + opt_order;
971
972	for (sb = 0; sb < opt_order; sb++)
973	lpc_cof_reversed[sb] = lpc_cof[-(sb + 1)];
974
975	// reconstruct raw samples
976	raw_samples = bd->raw_samples + smp;
977	lpc_cof = lpc_cof_reversed + opt_order;
978
979	for (; raw_samples < raw_samples_end; raw_samples++) {
980	y = 1 << 19;
981
982	for (sb = -opt_order; sb < 0; sb++)
983	y += MUL64(lpc_cof[sb], raw_samples[sb]);
984
985	*raw_samples -= y >> 20;
986	}
987
988	raw_samples = bd->raw_samples;
989
990	// restore previous samples in case that they have been altered
991	if (*bd->store_prev_samples)
992	memcpy(raw_samples - sconf->max_order, bd->prev_raw_samples,
993	sizeof(*raw_samples) * sconf->max_order);
994
995	return 0;
996	}
997
998
999	/** Read the block data.
1000	*/
1001	static int read_block(ALSDecContext *ctx, ALSBlockData *bd)
1002	{
1003	int ret;
1004	GetBitContext *gb = &ctx->gb;
1005	ALSSpecificConfig *sconf = &ctx->sconf;
1006
1007	*bd->shift_lsbs = 0;
1008	// read block type flag and read the samples accordingly
1009	if (get_bits1(gb)) {
1010	ret = read_var_block_data(ctx, bd);
1011	} else {
1012	ret = read_const_block_data(ctx, bd);
1013	}
1014
1015	if (!sconf->mc_coding || ctx->js_switch)
1016	align_get_bits(gb);
1017
1018	return ret;
1019	}
1020
1021
1022	/** Decode the block data.
1023	*/
1024	static int decode_block(ALSDecContext *ctx, ALSBlockData *bd)
1025	{
1026	unsigned int smp;
1027	int ret = 0;
1028
1029	// read block type flag and read the samples accordingly
1030	if (*bd->const_block)
1031	decode_const_block_data(ctx, bd);
1032	else
1033	ret = decode_var_block_data(ctx, bd); // always return 0
1034
1035	if (ret < 0)
1036	return ret;
1037
1038	// TODO: read RLSLMS extension data
1039
1040	if (*bd->shift_lsbs)
1041	for (smp = 0; smp < bd->block_length; smp++)
1042	bd->raw_samples[smp] <<= *bd->shift_lsbs;
1043
1044	return 0;
1045	}
1046
1047
1048	/** Read and decode block data successively.
1049	*/
1050	static int read_decode_block(ALSDecContext *ctx, ALSBlockData *bd)
1051	{
1052	int ret;
1053
1054	if ((ret = read_block(ctx, bd)) < 0)
1055	return ret;
1056
1057	return decode_block(ctx, bd);
1058	}
1059
1060
1061	/** Compute the number of samples left to decode for the current frame and
1062	* sets these samples to zero.
1063	*/
1064	static void zero_remaining(unsigned int b, unsigned int b_max,
1065	const unsigned int *div_blocks, int32_t *buf)
1066	{
1067	unsigned int count = 0;
1068
1069	while (b < b_max)
1070	count += div_blocks[b++];
1071
1072	if (count)
1073	memset(buf, 0, sizeof(*buf) * count);
1074	}
1075
1076
1077	/** Decode blocks independently.
1078	*/
1079	static int decode_blocks_ind(ALSDecContext *ctx, unsigned int ra_frame,
1080	unsigned int c, const unsigned int *div_blocks,
1081	unsigned int *js_blocks)
1082	{
1083	int ret;
1084	unsigned int b;
1085	ALSBlockData bd = { 0 };
1086
1087	bd.ra_block = ra_frame;
1088	bd.const_block = ctx->const_block;
1089	bd.shift_lsbs = ctx->shift_lsbs;
1090	bd.opt_order = ctx->opt_order;
1091	bd.store_prev_samples = ctx->store_prev_samples;
1092	bd.use_ltp = ctx->use_ltp;
1093	bd.ltp_lag = ctx->ltp_lag;
1094	bd.ltp_gain = ctx->ltp_gain[0];
1095	bd.quant_cof = ctx->quant_cof[0];
1096	bd.lpc_cof = ctx->lpc_cof[0];
1097	bd.prev_raw_samples = ctx->prev_raw_samples;
1098	bd.raw_samples = ctx->raw_samples[c];
1099
1100
1101	for (b = 0; b < ctx->num_blocks; b++) {
1102	bd.block_length = div_blocks[b];
1103
1104	if ((ret = read_decode_block(ctx, &bd)) < 0) {
1105	// damaged block, write zero for the rest of the frame
1106	zero_remaining(b, ctx->num_blocks, div_blocks, bd.raw_samples);
1107	return ret;
1108	}
1109	bd.raw_samples += div_blocks[b];
1110	bd.ra_block = 0;
1111	}
1112
1113	return 0;
1114	}
1115
1116
1117	/** Decode blocks dependently.
1118	*/
1119	static int decode_blocks(ALSDecContext *ctx, unsigned int ra_frame,
1120	unsigned int c, const unsigned int *div_blocks,
1121	unsigned int *js_blocks)
1122	{
1123	ALSSpecificConfig *sconf = &ctx->sconf;
1124	unsigned int offset = 0;
1125	unsigned int b;
1126	int ret;
1127	ALSBlockData bd[2] = { { 0 } };
1128
1129	bd[0].ra_block = ra_frame;
1130	bd[0].const_block = ctx->const_block;
1131	bd[0].shift_lsbs = ctx->shift_lsbs;
1132	bd[0].opt_order = ctx->opt_order;
1133	bd[0].store_prev_samples = ctx->store_prev_samples;
1134	bd[0].use_ltp = ctx->use_ltp;
1135	bd[0].ltp_lag = ctx->ltp_lag;
1136	bd[0].ltp_gain = ctx->ltp_gain[0];
1137	bd[0].quant_cof = ctx->quant_cof[0];
1138	bd[0].lpc_cof = ctx->lpc_cof[0];
1139	bd[0].prev_raw_samples = ctx->prev_raw_samples;
1140	bd[0].js_blocks = *js_blocks;
1141
1142	bd[1].ra_block = ra_frame;
1143	bd[1].const_block = ctx->const_block;
1144	bd[1].shift_lsbs = ctx->shift_lsbs;
1145	bd[1].opt_order = ctx->opt_order;
1146	bd[1].store_prev_samples = ctx->store_prev_samples;
1147	bd[1].use_ltp = ctx->use_ltp;
1148	bd[1].ltp_lag = ctx->ltp_lag;
1149	bd[1].ltp_gain = ctx->ltp_gain[0];
1150	bd[1].quant_cof = ctx->quant_cof[0];
1151	bd[1].lpc_cof = ctx->lpc_cof[0];
1152	bd[1].prev_raw_samples = ctx->prev_raw_samples;
1153	bd[1].js_blocks = *(js_blocks + 1);
1154
1155	// decode all blocks
1156	for (b = 0; b < ctx->num_blocks; b++) {
1157	unsigned int s;
1158
1159	bd[0].block_length = div_blocks[b];
1160	bd[1].block_length = div_blocks[b];
1161
1162	bd[0].raw_samples = ctx->raw_samples[c ] + offset;
1163	bd[1].raw_samples = ctx->raw_samples[c + 1] + offset;
1164
1165	bd[0].raw_other = bd[1].raw_samples;
1166	bd[1].raw_other = bd[0].raw_samples;
1167
1168	if ((ret = read_decode_block(ctx, &bd[0])) < 0 ||
1169	(ret = read_decode_block(ctx, &bd[1])) < 0)
1170	goto fail;
1171
1172	// reconstruct joint-stereo blocks
1173	if (bd[0].js_blocks) {
1174	if (bd[1].js_blocks)
1175	av_log(ctx->avctx, AV_LOG_WARNING, "Invalid channel pair.\n");
1176
1177	for (s = 0; s < div_blocks[b]; s++)
1178	bd[0].raw_samples[s] = bd[1].raw_samples[s] - bd[0].raw_samples[s];
1179	} else if (bd[1].js_blocks) {
1180	for (s = 0; s < div_blocks[b]; s++)
1181	bd[1].raw_samples[s] = bd[1].raw_samples[s] + bd[0].raw_samples[s];
1182	}
1183
1184	offset += div_blocks[b];
1185	bd[0].ra_block = 0;
1186	bd[1].ra_block = 0;
1187	}
1188
1189	// store carryover raw samples,
1190	// the others channel raw samples are stored by the calling function.
1191	memmove(ctx->raw_samples[c] - sconf->max_order,
1192	ctx->raw_samples[c] - sconf->max_order + sconf->frame_length,
1193	sizeof(*ctx->raw_samples[c]) * sconf->max_order);
1194
1195	return 0;
1196	fail:
1197	// damaged block, write zero for the rest of the frame
1198	zero_remaining(b, ctx->num_blocks, div_blocks, bd[0].raw_samples);
1199	zero_remaining(b, ctx->num_blocks, div_blocks, bd[1].raw_samples);
1200	return ret;
1201	}
1202
1203	static inline int als_weighting(GetBitContext *gb, int k, int off)
1204	{
1205	int idx = av_clip(decode_rice(gb, k) + off,
1206	0, FF_ARRAY_ELEMS(mcc_weightings) - 1);
1207	return mcc_weightings[idx];
1208	}
1209
1210	/** Read the channel data.
1211	*/
1212	static int read_channel_data(ALSDecContext *ctx, ALSChannelData *cd, int c)
1213	{
1214	GetBitContext *gb = &ctx->gb;
1215	ALSChannelData *current = cd;
1216	unsigned int channels = ctx->avctx->channels;
1217	int entries = 0;
1218
1219	while (entries < channels && !(current->stop_flag = get_bits1(gb))) {
1220	current->master_channel = get_bits_long(gb, av_ceil_log2(channels));
1221
1222	if (current->master_channel >= channels) {
1223	av_log(ctx->avctx, AV_LOG_ERROR, "Invalid master channel.\n");
1224	return AVERROR_INVALIDDATA;
1225	}
1226
1227	if (current->master_channel != c) {
1228	current->time_diff_flag = get_bits1(gb);
1229	current->weighting[0] = als_weighting(gb, 1, 16);
1230	current->weighting[1] = als_weighting(gb, 2, 14);
1231	current->weighting[2] = als_weighting(gb, 1, 16);
1232
1233	if (current->time_diff_flag) {
1234	current->weighting[3] = als_weighting(gb, 1, 16);
1235	current->weighting[4] = als_weighting(gb, 1, 16);
1236	current->weighting[5] = als_weighting(gb, 1, 16);
1237
1238	current->time_diff_sign = get_bits1(gb);
1239	current->time_diff_index = get_bits(gb, ctx->ltp_lag_length - 3) + 3;
1240	}
1241	}
1242
1243	current++;
1244	entries++;
1245	}
1246
1247	if (entries == channels) {
1248	av_log(ctx->avctx, AV_LOG_ERROR, "Damaged channel data.\n");
1249	return AVERROR_INVALIDDATA;
1250	}
1251
1252	align_get_bits(gb);
1253	return 0;
1254	}
1255
1256
1257	/** Recursively reverts the inter-channel correlation for a block.
1258	*/
1259	static int revert_channel_correlation(ALSDecContext *ctx, ALSBlockData *bd,
1260	ALSChannelData **cd, int *reverted,
1261	unsigned int offset, int c)
1262	{
1263	ALSChannelData *ch = cd[c];
1264	unsigned int dep = 0;
1265	unsigned int channels = ctx->avctx->channels;
1266	unsigned int channel_size = ctx->sconf.frame_length + ctx->sconf.max_order;
1267
1268	if (reverted[c])
1269	return 0;
1270
1271	reverted[c] = 1;
1272
1273	while (dep < channels && !ch[dep].stop_flag) {
1274	revert_channel_correlation(ctx, bd, cd, reverted, offset,
1275	ch[dep].master_channel);
1276
1277	dep++;
1278	}
1279
1280	if (dep == channels) {
1281	av_log(ctx->avctx, AV_LOG_WARNING, "Invalid channel correlation.\n");
1282	return AVERROR_INVALIDDATA;
1283	}
1284
1285	bd->const_block = ctx->const_block + c;
1286	bd->shift_lsbs = ctx->shift_lsbs + c;
1287	bd->opt_order = ctx->opt_order + c;
1288	bd->store_prev_samples = ctx->store_prev_samples + c;
1289	bd->use_ltp = ctx->use_ltp + c;
1290	bd->ltp_lag = ctx->ltp_lag + c;
1291	bd->ltp_gain = ctx->ltp_gain[c];
1292	bd->lpc_cof = ctx->lpc_cof[c];
1293	bd->quant_cof = ctx->quant_cof[c];
1294	bd->raw_samples = ctx->raw_samples[c] + offset;
1295
1296	for (dep = 0; !ch[dep].stop_flag; dep++) {
1297	ptrdiff_t smp;
1298	ptrdiff_t begin = 1;
1299	ptrdiff_t end = bd->block_length - 1;
1300	int64_t y;
1301	int32_t *master = ctx->raw_samples[ch[dep].master_channel] + offset;
1302
1303	if (ch[dep].master_channel == c)
1304	continue;
1305
1306	if (ch[dep].time_diff_flag) {
1307	int t = ch[dep].time_diff_index;
1308
1309	if (ch[dep].time_diff_sign) {
1310	t = -t;
1311	if (begin < t) {
1312	av_log(ctx->avctx, AV_LOG_ERROR, "begin %"PTRDIFF_SPECIFIER" smaller than time diff index %d.\n", begin, t);
1313	return AVERROR_INVALIDDATA;
1314	}
1315	begin -= t;
1316	} else {
1317	if (end < t) {
1318	av_log(ctx->avctx, AV_LOG_ERROR, "end %"PTRDIFF_SPECIFIER" smaller than time diff index %d.\n", end, t);
1319	return AVERROR_INVALIDDATA;
1320	}
1321	end -= t;
1322	}
1323
1324	if (FFMIN(begin - 1, begin - 1 + t) < ctx->raw_buffer - master ||
1325	FFMAX(end + 1, end + 1 + t) > ctx->raw_buffer + channels * channel_size - master) {
1326	av_log(ctx->avctx, AV_LOG_ERROR,
1327	"sample pointer range [%p, %p] not contained in raw_buffer [%p, %p].\n",
1328	master + FFMIN(begin - 1, begin - 1 + t), master + FFMAX(end + 1, end + 1 + t),
1329	ctx->raw_buffer, ctx->raw_buffer + channels * channel_size);
1330	return AVERROR_INVALIDDATA;
1331	}
1332
1333	for (smp = begin; smp < end; smp++) {
1334	y = (1 << 6) +
1335	MUL64(ch[dep].weighting[0], master[smp - 1 ]) +
1336	MUL64(ch[dep].weighting[1], master[smp ]) +
1337	MUL64(ch[dep].weighting[2], master[smp + 1 ]) +
1338	MUL64(ch[dep].weighting[3], master[smp - 1 + t]) +
1339	MUL64(ch[dep].weighting[4], master[smp + t]) +
1340	MUL64(ch[dep].weighting[5], master[smp + 1 + t]);
1341
1342	bd->raw_samples[smp] += y >> 7;
1343	}
1344	} else {
1345
1346	if (begin - 1 < ctx->raw_buffer - master ||
1347	end + 1 > ctx->raw_buffer + channels * channel_size - master) {
1348	av_log(ctx->avctx, AV_LOG_ERROR,
1349	"sample pointer range [%p, %p] not contained in raw_buffer [%p, %p].\n",
1350	master + begin - 1, master + end + 1,
1351	ctx->raw_buffer, ctx->raw_buffer + channels * channel_size);
1352	return AVERROR_INVALIDDATA;
1353	}
1354
1355	for (smp = begin; smp < end; smp++) {
1356	y = (1 << 6) +
1357	MUL64(ch[dep].weighting[0], master[smp - 1]) +
1358	MUL64(ch[dep].weighting[1], master[smp ]) +
1359	MUL64(ch[dep].weighting[2], master[smp + 1]);
1360
1361	bd->raw_samples[smp] += y >> 7;
1362	}
1363	}
1364	}
1365
1366	return 0;
1367	}
1368
1369
1370	/** multiply two softfloats and handle the rounding off
1371	*/
1372	static SoftFloat_IEEE754 multiply(SoftFloat_IEEE754 a, SoftFloat_IEEE754 b) {
1373	uint64_t mantissa_temp;
1374	uint64_t mask_64;
1375	int cutoff_bit_count;
1376	unsigned char last_2_bits;
1377	unsigned int mantissa;
1378	int32_t sign;
1379	uint32_t return_val = 0;
1380	int bit_count = 48;
1381
1382	sign = a.sign ^ b.sign;
1383
1384	// Multiply mantissa bits in a 64-bit register
1385	mantissa_temp = (uint64_t)a.mant * (uint64_t)b.mant;
1386	mask_64 = (uint64_t)0x1 << 47;
1387
1388	// Count the valid bit count
1389	while (!(mantissa_temp & mask_64) && mask_64) {
1390	bit_count--;
1391	mask_64 >>= 1;
1392	}
1393
1394	// Round off
1395	cutoff_bit_count = bit_count - 24;
1396	if (cutoff_bit_count > 0) {
1397	last_2_bits = (unsigned char)(((unsigned int)mantissa_temp >> (cutoff_bit_count - 1)) & 0x3 );
1398	if ((last_2_bits == 0x3) || ((last_2_bits == 0x1) && ((unsigned int)mantissa_temp & ((0x1UL << (cutoff_bit_count - 1)) - 1)))) {
1399	// Need to round up
1400	mantissa_temp += (uint64_t)0x1 << cutoff_bit_count;
1401	}
1402	}
1403
1404	mantissa = (unsigned int)(mantissa_temp >> cutoff_bit_count);
1405
1406	// Need one more shift?
1407	if (mantissa & 0x01000000ul) {
1408	bit_count++;
1409	mantissa >>= 1;
1410	}
1411
1412	if (!sign) {
1413	return_val = 0x80000000U;
1414	}
1415
1416	return_val |= (a.exp + b.exp + bit_count - 47) << 23;
1417	return_val |= mantissa;
1418	return av_bits2sf_ieee754(return_val);
1419	}
1420
1421
1422	/** Read and decode the floating point sample data
1423	*/
1424	static int read_diff_float_data(ALSDecContext *ctx, unsigned int ra_frame) {
1425	AVCodecContext *avctx = ctx->avctx;
1426	GetBitContext *gb = &ctx->gb;
1427	SoftFloat_IEEE754 *acf = ctx->acf;
1428	int *shift_value = ctx->shift_value;
1429	int *last_shift_value = ctx->last_shift_value;
1430	int *last_acf_mantissa = ctx->last_acf_mantissa;
1431	int **raw_mantissa = ctx->raw_mantissa;
1432	int *nbits = ctx->nbits;
1433	unsigned char *larray = ctx->larray;
1434	int frame_length = ctx->cur_frame_length;
1435	SoftFloat_IEEE754 scale = av_int2sf_ieee754(0x1u, 23);
1436	unsigned int partA_flag;
1437	unsigned int highest_byte;
1438	unsigned int shift_amp;
1439	uint32_t tmp_32;
1440	int use_acf;
1441	int nchars;
1442	int i;
1443	int c;
1444	long k;
1445	long nbits_aligned;
1446	unsigned long acc;
1447	unsigned long j;
1448	uint32_t sign;
1449	uint32_t e;
1450	uint32_t mantissa;
1451
1452	skip_bits_long(gb, 32); //num_bytes_diff_float
1453	use_acf = get_bits1(gb);
1454
1455	if (ra_frame) {
1456	memset(last_acf_mantissa, 0, avctx->channels * sizeof(*last_acf_mantissa));
1457	memset(last_shift_value, 0, avctx->channels * sizeof(*last_shift_value) );
1458	ff_mlz_flush_dict(ctx->mlz);
1459	}
1460
1461	for (c = 0; c < avctx->channels; ++c) {
1462	if (use_acf) {
1463	//acf_flag
1464	if (get_bits1(gb)) {
1465	tmp_32 = get_bits(gb, 23);
1466	last_acf_mantissa[c] = tmp_32;
1467	} else {
1468	tmp_32 = last_acf_mantissa[c];
1469	}
1470	acf[c] = av_bits2sf_ieee754(tmp_32);
1471	} else {
1472	acf[c] = FLOAT_1;
1473	}
1474
1475	highest_byte = get_bits(gb, 2);
1476	partA_flag = get_bits1(gb);
1477	shift_amp = get_bits1(gb);
1478
1479	if (shift_amp) {
1480	shift_value[c] = get_bits(gb, 8);
1481	last_shift_value[c] = shift_value[c];
1482	} else {
1483	shift_value[c] = last_shift_value[c];
1484	}
1485
1486	if (partA_flag) {
1487	if (!get_bits1(gb)) { //uncompressed
1488	for (i = 0; i < frame_length; ++i) {
1489	if (ctx->raw_samples[c][i] == 0) {
1490	ctx->raw_mantissa[c][i] = get_bits_long(gb, 32);
1491	}
1492	}
1493	} else { //compressed
1494	nchars = 0;
1495	for (i = 0; i < frame_length; ++i) {
1496	if (ctx->raw_samples[c][i] == 0) {
1497	nchars += 4;
1498	}
1499	}
1500
1501	tmp_32 = ff_mlz_decompression(ctx->mlz, gb, nchars, larray);
1502	if(tmp_32 != nchars) {
1503	av_log(ctx->avctx, AV_LOG_ERROR, "Error in MLZ decompression (%"PRId32", %d).\n", tmp_32, nchars);
1504	return AVERROR_INVALIDDATA;
1505	}
1506
1507	for (i = 0; i < frame_length; ++i) {
1508	ctx->raw_mantissa[c][i] = AV_RB32(larray);
1509	}
1510	}
1511	}
1512
1513	//decode part B
1514	if (highest_byte) {
1515	for (i = 0; i < frame_length; ++i) {
1516	if (ctx->raw_samples[c][i] != 0) {
1517	//The following logic is taken from Tabel 14.45 and 14.46 from the ISO spec
1518	if (av_cmp_sf_ieee754(acf[c], FLOAT_1)) {
1519	nbits[i] = 23 - av_log2(abs(ctx->raw_samples[c][i]));
1520	} else {
1521	nbits[i] = 23;
1522	}
1523	nbits[i] = FFMIN(nbits[i], highest_byte*8);
1524	}
1525	}
1526
1527	if (!get_bits1(gb)) { //uncompressed
1528	for (i = 0; i < frame_length; ++i) {
1529	if (ctx->raw_samples[c][i] != 0) {
1530	raw_mantissa[c][i] = get_bitsz(gb, nbits[i]);
1531	}
1532	}
1533	} else { //compressed
1534	nchars = 0;
1535	for (i = 0; i < frame_length; ++i) {
1536	if (ctx->raw_samples[c][i]) {
1537	nchars += (int) nbits[i] / 8;
1538	if (nbits[i] & 7) {
1539	++nchars;
1540	}
1541	}
1542	}
1543
1544	tmp_32 = ff_mlz_decompression(ctx->mlz, gb, nchars, larray);
1545	if(tmp_32 != nchars) {
1546	av_log(ctx->avctx, AV_LOG_ERROR, "Error in MLZ decompression (%"PRId32", %d).\n", tmp_32, nchars);
1547	return AVERROR_INVALIDDATA;
1548	}
1549
1550	j = 0;
1551	for (i = 0; i < frame_length; ++i) {
1552	if (ctx->raw_samples[c][i]) {
1553	if (nbits[i] & 7) {
1554	nbits_aligned = 8 * ((unsigned int)(nbits[i] / 8) + 1);
1555	} else {
1556	nbits_aligned = nbits[i];
1557	}
1558	acc = 0;
1559	for (k = 0; k < nbits_aligned/8; ++k) {
1560	acc = (acc << 8) + larray[j++];
1561	}
1562	acc >>= (nbits_aligned - nbits[i]);
1563	raw_mantissa[c][i] = acc;
1564	}
1565	}
1566	}
1567	}
1568
1569	for (i = 0; i < frame_length; ++i) {
1570	SoftFloat_IEEE754 pcm_sf = av_int2sf_ieee754(ctx->raw_samples[c][i], 0);
1571	pcm_sf = av_div_sf_ieee754(pcm_sf, scale);
1572
1573	if (ctx->raw_samples[c][i] != 0) {
1574	if (!av_cmp_sf_ieee754(acf[c], FLOAT_1)) {
1575	pcm_sf = multiply(acf[c], pcm_sf);
1576	}
1577
1578	sign = pcm_sf.sign;
1579	e = pcm_sf.exp;
1580	mantissa = (pcm_sf.mant | 0x800000) + raw_mantissa[c][i];
1581
1582	while(mantissa >= 0x1000000) {
1583	e++;
1584	mantissa >>= 1;
1585	}
1586
1587	if (mantissa) e += (shift_value[c] - 127);
1588	mantissa &= 0x007fffffUL;
1589
1590	tmp_32 = (sign << 31) | ((e + EXP_BIAS) << 23) | (mantissa);
1591	ctx->raw_samples[c][i] = tmp_32;
1592	} else {
1593	ctx->raw_samples[c][i] = raw_mantissa[c][i] & 0x007fffffUL;
1594	}
1595	}
1596	align_get_bits(gb);
1597	}
1598	return 0;
1599	}
1600
1601
1602	/** Read the frame data.
1603	*/
1604	static int read_frame_data(ALSDecContext *ctx, unsigned int ra_frame)
1605	{
1606	ALSSpecificConfig *sconf = &ctx->sconf;
1607	AVCodecContext *avctx = ctx->avctx;
1608	GetBitContext *gb = &ctx->gb;
1609	unsigned int div_blocks[32]; ///< block sizes.
1610	unsigned int c;
1611	unsigned int js_blocks[2];
1612	uint32_t bs_info = 0;
1613	int ret;
1614
1615	// skip the size of the ra unit if present in the frame
1616	if (sconf->ra_flag == RA_FLAG_FRAMES && ra_frame)
1617	skip_bits_long(gb, 32);
1618
1619	if (sconf->mc_coding && sconf->joint_stereo) {
1620	ctx->js_switch = get_bits1(gb);
1621	align_get_bits(gb);
1622	}
1623
1624	if (!sconf->mc_coding || ctx->js_switch) {
1625	int independent_bs = !sconf->joint_stereo;
1626
1627	for (c = 0; c < avctx->channels; c++) {
1628	js_blocks[0] = 0;
1629	js_blocks[1] = 0;
1630
1631	get_block_sizes(ctx, div_blocks, &bs_info);
1632
1633	// if joint_stereo and block_switching is set, independent decoding
1634	// is signaled via the first bit of bs_info
1635	if (sconf->joint_stereo && sconf->block_switching)
1636	if (bs_info >> 31)
1637	independent_bs = 2;
1638
1639	// if this is the last channel, it has to be decoded independently
1640	if (c == avctx->channels - 1)
1641	independent_bs = 1;
1642
1643	if (independent_bs) {
1644	ret = decode_blocks_ind(ctx, ra_frame, c,
1645	div_blocks, js_blocks);
1646	if (ret < 0)
1647	return ret;
1648	independent_bs--;
1649	} else {
1650	ret = decode_blocks(ctx, ra_frame, c, div_blocks, js_blocks);
1651	if (ret < 0)
1652	return ret;
1653
1654	c++;
1655	}
1656
1657	// store carryover raw samples
1658	memmove(ctx->raw_samples[c] - sconf->max_order,
1659	ctx->raw_samples[c] - sconf->max_order + sconf->frame_length,
1660	sizeof(*ctx->raw_samples[c]) * sconf->max_order);
1661	}
1662	} else { // multi-channel coding
1663	ALSBlockData bd = { 0 };
1664	int b, ret;
1665	int *reverted_channels = ctx->reverted_channels;
1666	unsigned int offset = 0;
1667
1668	for (c = 0; c < avctx->channels; c++)
1669	if (ctx->chan_data[c] < ctx->chan_data_buffer) {
1670	av_log(ctx->avctx, AV_LOG_ERROR, "Invalid channel data.\n");
1671	return AVERROR_INVALIDDATA;
1672	}
1673
1674	memset(reverted_channels, 0, sizeof(*reverted_channels) * avctx->channels);
1675
1676	bd.ra_block = ra_frame;
1677	bd.prev_raw_samples = ctx->prev_raw_samples;
1678
1679	get_block_sizes(ctx, div_blocks, &bs_info);
1680
1681	for (b = 0; b < ctx->num_blocks; b++) {
1682	bd.block_length = div_blocks[b];
1683	if (bd.block_length <= 0) {
1684	av_log(ctx->avctx, AV_LOG_WARNING,
1685	"Invalid block length %u in channel data!\n",
1686	bd.block_length);
1687	continue;
1688	}
1689
1690	for (c = 0; c < avctx->channels; c++) {
1691	bd.const_block = ctx->const_block + c;
1692	bd.shift_lsbs = ctx->shift_lsbs + c;
1693	bd.opt_order = ctx->opt_order + c;
1694	bd.store_prev_samples = ctx->store_prev_samples + c;
1695	bd.use_ltp = ctx->use_ltp + c;
1696	bd.ltp_lag = ctx->ltp_lag + c;
1697	bd.ltp_gain = ctx->ltp_gain[c];
1698	bd.lpc_cof = ctx->lpc_cof[c];
1699	bd.quant_cof = ctx->quant_cof[c];
1700	bd.raw_samples = ctx->raw_samples[c] + offset;
1701	bd.raw_other = NULL;
1702
1703	if ((ret = read_block(ctx, &bd)) < 0)
1704	return ret;
1705	if ((ret = read_channel_data(ctx, ctx->chan_data[c], c)) < 0)
1706	return ret;
1707	}
1708
1709	for (c = 0; c < avctx->channels; c++) {
1710	ret = revert_channel_correlation(ctx, &bd, ctx->chan_data,
1711	reverted_channels, offset, c);
1712	if (ret < 0)
1713	return ret;
1714	}
1715	for (c = 0; c < avctx->channels; c++) {
1716	bd.const_block = ctx->const_block + c;
1717	bd.shift_lsbs = ctx->shift_lsbs + c;
1718	bd.opt_order = ctx->opt_order + c;
1719	bd.store_prev_samples = ctx->store_prev_samples + c;
1720	bd.use_ltp = ctx->use_ltp + c;
1721	bd.ltp_lag = ctx->ltp_lag + c;
1722	bd.ltp_gain = ctx->ltp_gain[c];
1723	bd.lpc_cof = ctx->lpc_cof[c];
1724	bd.quant_cof = ctx->quant_cof[c];
1725	bd.raw_samples = ctx->raw_samples[c] + offset;
1726
1727	if ((ret = decode_block(ctx, &bd)) < 0)
1728	return ret;
1729	}
1730
1731	memset(reverted_channels, 0, avctx->channels * sizeof(*reverted_channels));
1732	offset += div_blocks[b];
1733	bd.ra_block = 0;
1734	}
1735
1736	// store carryover raw samples
1737	for (c = 0; c < avctx->channels; c++)
1738	memmove(ctx->raw_samples[c] - sconf->max_order,
1739	ctx->raw_samples[c] - sconf->max_order + sconf->frame_length,
1740	sizeof(*ctx->raw_samples[c]) * sconf->max_order);
1741	}
1742
1743	if (sconf->floating) {
1744	read_diff_float_data(ctx, ra_frame);
1745	}
1746
1747	if (get_bits_left(gb) < 0) {
1748	av_log(ctx->avctx, AV_LOG_ERROR, "Overread %d\n", -get_bits_left(gb));
1749	return AVERROR_INVALIDDATA;
1750	}
1751
1752	return 0;
1753	}
1754
1755
1756	/** Decode an ALS frame.
1757	*/
1758	static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame_ptr,
1759	AVPacket *avpkt)
1760	{
1761	ALSDecContext *ctx = avctx->priv_data;
1762	AVFrame *frame = data;
1763	ALSSpecificConfig *sconf = &ctx->sconf;
1764	const uint8_t *buffer = avpkt->data;
1765	int buffer_size = avpkt->size;
1766	int invalid_frame, ret;
1767	unsigned int c, sample, ra_frame, bytes_read, shift;
1768
1769	if ((ret = init_get_bits8(&ctx->gb, buffer, buffer_size)) < 0)
1770	return ret;
1771
1772	// In the case that the distance between random access frames is set to zero
1773	// (sconf->ra_distance == 0) no frame is treated as a random access frame.
1774	// For the first frame, if prediction is used, all samples used from the
1775	// previous frame are assumed to be zero.
1776	ra_frame = sconf->ra_distance && !(ctx->frame_id % sconf->ra_distance);
1777
1778	// the last frame to decode might have a different length
1779	if (sconf->samples != 0xFFFFFFFF)
1780	ctx->cur_frame_length = FFMIN(sconf->samples - ctx->frame_id * (uint64_t) sconf->frame_length,
1781	sconf->frame_length);
1782	else
1783	ctx->cur_frame_length = sconf->frame_length;
1784
1785	// decode the frame data
1786	if ((invalid_frame = read_frame_data(ctx, ra_frame)) < 0)
1787	av_log(ctx->avctx, AV_LOG_WARNING,
1788	"Reading frame data failed. Skipping RA unit.\n");
1789
1790	ctx->frame_id++;
1791
1792	/* get output buffer */
1793	frame->nb_samples = ctx->cur_frame_length;
1794	if ((ret = ff_get_buffer(avctx, frame, 0)) < 0)
1795	return ret;
1796
1797	// transform decoded frame into output format
1798	#define INTERLEAVE_OUTPUT(bps) \
1799	{ \
1800	int##bps##_t *dest = (int##bps##_t*)frame->data[0]; \
1801	shift = bps - ctx->avctx->bits_per_raw_sample; \
1802	if (!ctx->cs_switch) { \
1803	for (sample = 0; sample < ctx->cur_frame_length; sample++) \
1804	for (c = 0; c < avctx->channels; c++) \
1805	*dest++ = ctx->raw_samples[c][sample] << shift; \
1806	} else { \
1807	for (sample = 0; sample < ctx->cur_frame_length; sample++) \
1808	for (c = 0; c < avctx->channels; c++) \
1809	*dest++ = ctx->raw_samples[sconf->chan_pos[c]][sample] << shift; \
1810	} \
1811	}
1812
1813	if (ctx->avctx->bits_per_raw_sample <= 16) {
1814	INTERLEAVE_OUTPUT(16)
1815	} else {
1816	INTERLEAVE_OUTPUT(32)
1817	}
1818
1819	// update CRC
1820	if (sconf->crc_enabled && (avctx->err_recognition & (AV_EF_CRCCHECK|AV_EF_CAREFUL))) {
1821	int swap = HAVE_BIGENDIAN != sconf->msb_first;
1822
1823	if (ctx->avctx->bits_per_raw_sample == 24) {
1824	int32_t *src = (int32_t *)frame->data[0];
1825
1826	for (sample = 0;
1827	sample < ctx->cur_frame_length * avctx->channels;
1828	sample++) {
1829	int32_t v;
1830
1831	if (swap)
1832	v = av_bswap32(src[sample]);
1833	else
1834	v = src[sample];
1835	if (!HAVE_BIGENDIAN)
1836	v >>= 8;
1837
1838	ctx->crc = av_crc(ctx->crc_table, ctx->crc, (uint8_t*)(&v), 3);
1839	}
1840	} else {
1841	uint8_t *crc_source;
1842
1843	if (swap) {
1844	if (ctx->avctx->bits_per_raw_sample <= 16) {
1845	int16_t *src = (int16_t*) frame->data[0];
1846	int16_t *dest = (int16_t*) ctx->crc_buffer;
1847	for (sample = 0;
1848	sample < ctx->cur_frame_length * avctx->channels;
1849	sample++)
1850	*dest++ = av_bswap16(src[sample]);
1851	} else {
1852	ctx->bdsp.bswap_buf((uint32_t *) ctx->crc_buffer,
1853	(uint32_t *) frame->data[0],
1854	ctx->cur_frame_length * avctx->channels);
1855	}
1856	crc_source = ctx->crc_buffer;
1857	} else {
1858	crc_source = frame->data[0];
1859	}
1860
1861	ctx->crc = av_crc(ctx->crc_table, ctx->crc, crc_source,
1862	ctx->cur_frame_length * avctx->channels *
1863	av_get_bytes_per_sample(avctx->sample_fmt));
1864	}
1865
1866
1867	// check CRC sums if this is the last frame
1868	if (ctx->cur_frame_length != sconf->frame_length &&
1869	ctx->crc_org != ctx->crc) {
1870	av_log(avctx, AV_LOG_ERROR, "CRC error.\n");
1871	if (avctx->err_recognition & AV_EF_EXPLODE)
1872	return AVERROR_INVALIDDATA;
1873	}
1874	}
1875
1876	*got_frame_ptr = 1;
1877
1878	bytes_read = invalid_frame ? buffer_size :
1879	(get_bits_count(&ctx->gb) + 7) >> 3;
1880
1881	return bytes_read;
1882	}
1883
1884
1885	/** Uninitialize the ALS decoder.
1886	*/
1887	static av_cold int decode_end(AVCodecContext *avctx)
1888	{
1889	ALSDecContext *ctx = avctx->priv_data;
1890	int i;
1891
1892	av_freep(&ctx->sconf.chan_pos);
1893
1894	ff_bgmc_end(&ctx->bgmc_lut, &ctx->bgmc_lut_status);
1895
1896	av_freep(&ctx->const_block);
1897	av_freep(&ctx->shift_lsbs);
1898	av_freep(&ctx->opt_order);
1899	av_freep(&ctx->store_prev_samples);
1900	av_freep(&ctx->use_ltp);
1901	av_freep(&ctx->ltp_lag);
1902	av_freep(&ctx->ltp_gain);
1903	av_freep(&ctx->ltp_gain_buffer);
1904	av_freep(&ctx->quant_cof);
1905	av_freep(&ctx->lpc_cof);
1906	av_freep(&ctx->quant_cof_buffer);
1907	av_freep(&ctx->lpc_cof_buffer);
1908	av_freep(&ctx->lpc_cof_reversed_buffer);
1909	av_freep(&ctx->prev_raw_samples);
1910	av_freep(&ctx->raw_samples);
1911	av_freep(&ctx->raw_buffer);
1912	av_freep(&ctx->chan_data);
1913	av_freep(&ctx->chan_data_buffer);
1914	av_freep(&ctx->reverted_channels);
1915	av_freep(&ctx->crc_buffer);
1916	if (ctx->mlz) {
1917	av_freep(&ctx->mlz->dict);
1918	av_freep(&ctx->mlz);
1919	}
1920	av_freep(&ctx->acf);
1921	av_freep(&ctx->last_acf_mantissa);
1922	av_freep(&ctx->shift_value);
1923	av_freep(&ctx->last_shift_value);
1924	if (ctx->raw_mantissa) {
1925	for (i = 0; i < avctx->channels; i++) {
1926	av_freep(&ctx->raw_mantissa[i]);
1927	}
1928	av_freep(&ctx->raw_mantissa);
1929	}
1930	av_freep(&ctx->larray);
1931	av_freep(&ctx->nbits);
1932
1933	return 0;
1934	}
1935
1936
1937	/** Initialize the ALS decoder.
1938	*/
1939	static av_cold int decode_init(AVCodecContext *avctx)
1940	{
1941	unsigned int c;
1942	unsigned int channel_size;
1943	int num_buffers, ret;
1944	ALSDecContext *ctx = avctx->priv_data;
1945	ALSSpecificConfig *sconf = &ctx->sconf;
1946	ctx->avctx = avctx;
1947
1948	if (!avctx->extradata) {
1949	av_log(avctx, AV_LOG_ERROR, "Missing required ALS extradata.\n");
1950	return AVERROR_INVALIDDATA;
1951	}
1952
1953	if ((ret = read_specific_config(ctx)) < 0) {
1954	av_log(avctx, AV_LOG_ERROR, "Reading ALSSpecificConfig failed.\n");
1955	goto fail;
1956	}
1957
1958	if ((ret = check_specific_config(ctx)) < 0) {
1959	goto fail;
1960	}
1961
1962	if (sconf->bgmc) {
1963	ret = ff_bgmc_init(avctx, &ctx->bgmc_lut, &ctx->bgmc_lut_status);
1964	if (ret < 0)
1965	goto fail;
1966	}
1967	if (sconf->floating) {
1968	avctx->sample_fmt = AV_SAMPLE_FMT_FLT;
1969	avctx->bits_per_raw_sample = 32;
1970	} else {
1971	avctx->sample_fmt = sconf->resolution > 1
1972	? AV_SAMPLE_FMT_S32 : AV_SAMPLE_FMT_S16;
1973	avctx->bits_per_raw_sample = (sconf->resolution + 1) * 8;
1974	if (avctx->bits_per_raw_sample > 32) {
1975	av_log(avctx, AV_LOG_ERROR, "Bits per raw sample %d larger than 32.\n",
1976	avctx->bits_per_raw_sample);
1977	ret = AVERROR_INVALIDDATA;
1978	goto fail;
1979	}
1980	}
1981
1982	// set maximum Rice parameter for progressive decoding based on resolution
1983	// This is not specified in 14496-3 but actually done by the reference
1984	// codec RM22 revision 2.
1985	ctx->s_max = sconf->resolution > 1 ? 31 : 15;
1986
1987	// set lag value for long-term prediction
1988	ctx->ltp_lag_length = 8 + (avctx->sample_rate >= 96000) +
1989	(avctx->sample_rate >= 192000);
1990
1991	// allocate quantized parcor coefficient buffer
1992	num_buffers = sconf->mc_coding ? avctx->channels : 1;
1993
1994	ctx->quant_cof = av_malloc_array(num_buffers, sizeof(*ctx->quant_cof));
1995	ctx->lpc_cof = av_malloc_array(num_buffers, sizeof(*ctx->lpc_cof));
1996	ctx->quant_cof_buffer = av_malloc_array(num_buffers * sconf->max_order,
1997	sizeof(*ctx->quant_cof_buffer));
1998	ctx->lpc_cof_buffer = av_malloc_array(num_buffers * sconf->max_order,
1999	sizeof(*ctx->lpc_cof_buffer));
2000	ctx->lpc_cof_reversed_buffer = av_malloc_array(sconf->max_order,
2001	sizeof(*ctx->lpc_cof_buffer));
2002
2003	if (!ctx->quant_cof || !ctx->lpc_cof ||
2004	!ctx->quant_cof_buffer || !ctx->lpc_cof_buffer ||
2005	!ctx->lpc_cof_reversed_buffer) {
2006	av_log(avctx, AV_LOG_ERROR, "Allocating buffer memory failed.\n");
2007	ret = AVERROR(ENOMEM);
2008	goto fail;
2009	}
2010
2011	// assign quantized parcor coefficient buffers
2012	for (c = 0; c < num_buffers; c++) {
2013	ctx->quant_cof[c] = ctx->quant_cof_buffer + c * sconf->max_order;
2014	ctx->lpc_cof[c] = ctx->lpc_cof_buffer + c * sconf->max_order;
2015	}
2016
2017	// allocate and assign lag and gain data buffer for ltp mode
2018	ctx->const_block = av_malloc_array(num_buffers, sizeof(*ctx->const_block));
2019	ctx->shift_lsbs = av_malloc_array(num_buffers, sizeof(*ctx->shift_lsbs));
2020	ctx->opt_order = av_malloc_array(num_buffers, sizeof(*ctx->opt_order));
2021	ctx->store_prev_samples = av_malloc_array(num_buffers, sizeof(*ctx->store_prev_samples));
2022	ctx->use_ltp = av_mallocz_array(num_buffers, sizeof(*ctx->use_ltp));
2023	ctx->ltp_lag = av_malloc_array(num_buffers, sizeof(*ctx->ltp_lag));
2024	ctx->ltp_gain = av_malloc_array(num_buffers, sizeof(*ctx->ltp_gain));
2025	ctx->ltp_gain_buffer = av_malloc_array(num_buffers * 5, sizeof(*ctx->ltp_gain_buffer));
2026
2027	if (!ctx->const_block || !ctx->shift_lsbs ||
2028	!ctx->opt_order || !ctx->store_prev_samples ||
2029	!ctx->use_ltp || !ctx->ltp_lag ||
2030	!ctx->ltp_gain || !ctx->ltp_gain_buffer) {
2031	av_log(avctx, AV_LOG_ERROR, "Allocating buffer memory failed.\n");
2032	ret = AVERROR(ENOMEM);
2033	goto fail;
2034	}
2035
2036	for (c = 0; c < num_buffers; c++)
2037	ctx->ltp_gain[c] = ctx->ltp_gain_buffer + c * 5;
2038
2039	// allocate and assign channel data buffer for mcc mode
2040	if (sconf->mc_coding) {
2041	ctx->chan_data_buffer = av_mallocz_array(num_buffers * num_buffers,
2042	sizeof(*ctx->chan_data_buffer));
2043	ctx->chan_data = av_mallocz_array(num_buffers,
2044	sizeof(*ctx->chan_data));
2045	ctx->reverted_channels = av_malloc_array(num_buffers,
2046	sizeof(*ctx->reverted_channels));
2047
2048	if (!ctx->chan_data_buffer || !ctx->chan_data || !ctx->reverted_channels) {
2049	av_log(avctx, AV_LOG_ERROR, "Allocating buffer memory failed.\n");
2050	ret = AVERROR(ENOMEM);
2051	goto fail;
2052	}
2053
2054	for (c = 0; c < num_buffers; c++)
2055	ctx->chan_data[c] = ctx->chan_data_buffer + c * num_buffers;
2056	} else {
2057	ctx->chan_data = NULL;
2058	ctx->chan_data_buffer = NULL;
2059	ctx->reverted_channels = NULL;
2060	}
2061
2062	channel_size = sconf->frame_length + sconf->max_order;
2063
2064	ctx->prev_raw_samples = av_malloc_array(sconf->max_order, sizeof(*ctx->prev_raw_samples));
2065	ctx->raw_buffer = av_mallocz_array(avctx->channels * channel_size, sizeof(*ctx->raw_buffer));
2066	ctx->raw_samples = av_malloc_array(avctx->channels, sizeof(*ctx->raw_samples));
2067
2068	if (sconf->floating) {
2069	ctx->acf = av_malloc_array(avctx->channels, sizeof(*ctx->acf));
2070	ctx->shift_value = av_malloc_array(avctx->channels, sizeof(*ctx->shift_value));
2071	ctx->last_shift_value = av_malloc_array(avctx->channels, sizeof(*ctx->last_shift_value));
2072	ctx->last_acf_mantissa = av_malloc_array(avctx->channels, sizeof(*ctx->last_acf_mantissa));
2073	ctx->raw_mantissa = av_mallocz_array(avctx->channels, sizeof(*ctx->raw_mantissa));
2074
2075	ctx->larray = av_malloc_array(ctx->cur_frame_length * 4, sizeof(*ctx->larray));
2076	ctx->nbits = av_malloc_array(ctx->cur_frame_length, sizeof(*ctx->nbits));
2077	ctx->mlz = av_mallocz(sizeof(*ctx->mlz));
2078
2079	if (!ctx->mlz || !ctx->acf || !ctx->shift_value || !ctx->last_shift_value
2080	|| !ctx->last_acf_mantissa || !ctx->raw_mantissa) {
2081	av_log(avctx, AV_LOG_ERROR, "Allocating buffer memory failed.\n");
2082	ret = AVERROR(ENOMEM);
2083	goto fail;
2084	}
2085
2086	ff_mlz_init_dict(avctx, ctx->mlz);
2087	ff_mlz_flush_dict(ctx->mlz);
2088
2089	for (c = 0; c < avctx->channels; ++c) {
2090	ctx->raw_mantissa[c] = av_mallocz_array(ctx->cur_frame_length, sizeof(**ctx->raw_mantissa));
2091	}
2092	}
2093
2094	// allocate previous raw sample buffer
2095	if (!ctx->prev_raw_samples || !ctx->raw_buffer|| !ctx->raw_samples) {
2096	av_log(avctx, AV_LOG_ERROR, "Allocating buffer memory failed.\n");
2097	ret = AVERROR(ENOMEM);
2098	goto fail;
2099	}
2100
2101	// assign raw samples buffers
2102	ctx->raw_samples[0] = ctx->raw_buffer + sconf->max_order;
2103	for (c = 1; c < avctx->channels; c++)
2104	ctx->raw_samples[c] = ctx->raw_samples[c - 1] + channel_size;
2105
2106	// allocate crc buffer
2107	if (HAVE_BIGENDIAN != sconf->msb_first && sconf->crc_enabled &&
2108	(avctx->err_recognition & (AV_EF_CRCCHECK|AV_EF_CAREFUL))) {
2109	ctx->crc_buffer = av_malloc_array(ctx->cur_frame_length *
2110	avctx->channels *
2111	av_get_bytes_per_sample(avctx->sample_fmt),
2112	sizeof(*ctx->crc_buffer));
2113	if (!ctx->crc_buffer) {
2114	av_log(avctx, AV_LOG_ERROR, "Allocating buffer memory failed.\n");
2115	ret = AVERROR(ENOMEM);
2116	goto fail;
2117	}
2118	}
2119
2120	ff_bswapdsp_init(&ctx->bdsp);
2121
2122	return 0;
2123
2124	fail:
2125	decode_end(avctx);
2126	return ret;
2127	}
2128
2129
2130	/** Flush (reset) the frame ID after seeking.
2131	*/
2132	static av_cold void flush(AVCodecContext *avctx)
2133	{
2134	ALSDecContext *ctx = avctx->priv_data;
2135
2136	ctx->frame_id = 0;
2137	}
2138
2139
2140	AVCodec ff_als_decoder = {
2141	.name = "als",
2142	.long_name = NULL_IF_CONFIG_SMALL("MPEG-4 Audio Lossless Coding (ALS)"),
2143	.type = AVMEDIA_TYPE_AUDIO,
2144	.id = AV_CODEC_ID_MP4ALS,
2145	.priv_data_size = sizeof(ALSDecContext),
2146	.init = decode_init,
2147	.close = decode_end,
2148	.decode = decode_frame,
2149	.flush = flush,
2150	.capabilities = AV_CODEC_CAP_SUBFRAMES | AV_CODEC_CAP_DR1,
2151	};
2152