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1 | /* |
2 | * AC-3 Audio Decoder | |
3 | * This code was developed as part of Google Summer of Code 2006. | |
4 | * E-AC-3 support was added as part of Google Summer of Code 2007. | |
5 | * | |
6 | * Copyright (c) 2006 Kartikey Mahendra BHATT (bhattkm at gmail dot com) | |
7 | * Copyright (c) 2007-2008 Bartlomiej Wolowiec <bartek.wolowiec@gmail.com> | |
8 | * Copyright (c) 2007 Justin Ruggles <justin.ruggles@gmail.com> | |
9 | * | |
10 | * This file is part of FFmpeg. | |
11 | * | |
12 | * FFmpeg is free software; you can redistribute it and/or | |
13 | * modify it under the terms of the GNU Lesser General Public | |
14 | * License as published by the Free Software Foundation; either | |
15 | * version 2.1 of the License, or (at your option) any later version. | |
16 | * | |
17 | * FFmpeg is distributed in the hope that it will be useful, | |
18 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
19 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
20 | * Lesser General Public License for more details. | |
21 | * | |
22 | * You should have received a copy of the GNU Lesser General Public | |
23 | * License along with FFmpeg; if not, write to the Free Software | |
24 | * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA | |
25 | */ | |
26 | ||
27 | #include <stdio.h> | |
28 | #include <stddef.h> | |
29 | #include <math.h> | |
30 | #include <string.h> | |
31 | ||
32 | #include "libavutil/channel_layout.h" | |
33 | #include "libavutil/crc.h" | |
34 | #include "libavutil/downmix_info.h" | |
35 | #include "libavutil/opt.h" | |
36 | #include "bswapdsp.h" | |
37 | #include "internal.h" | |
38 | #include "aac_ac3_parser.h" | |
39 | #include "ac3_parser.h" | |
40 | #include "ac3dec.h" | |
41 | #include "ac3dec_data.h" | |
42 | #include "kbdwin.h" | |
43 | ||
44 | /** | |
45 | * table for ungrouping 3 values in 7 bits. | |
46 | * used for exponents and bap=2 mantissas | |
47 | */ | |
48 | static uint8_t ungroup_3_in_7_bits_tab[128][3]; | |
49 | ||
50 | /** tables for ungrouping mantissas */ | |
51 | static int b1_mantissas[32][3]; | |
52 | static int b2_mantissas[128][3]; | |
53 | static int b3_mantissas[8]; | |
54 | static int b4_mantissas[128][2]; | |
55 | static int b5_mantissas[16]; | |
56 | ||
57 | /** | |
58 | * Quantization table: levels for symmetric. bits for asymmetric. | |
59 | * reference: Table 7.18 Mapping of bap to Quantizer | |
60 | */ | |
61 | static const uint8_t quantization_tab[16] = { | |
62 | 0, 3, 5, 7, 11, 15, | |
63 | 5, 6, 7, 8, 9, 10, 11, 12, 14, 16 | |
64 | }; | |
65 | ||
66 | /** dynamic range table. converts codes to scale factors. */ | |
67 | static float dynamic_range_tab[256]; | |
68 | static float heavy_dynamic_range_tab[256]; | |
69 | ||
70 | /** Adjustments in dB gain */ | |
71 | static const float gain_levels[9] = { | |
72 | LEVEL_PLUS_3DB, | |
73 | LEVEL_PLUS_1POINT5DB, | |
74 | LEVEL_ONE, | |
75 | LEVEL_MINUS_1POINT5DB, | |
76 | LEVEL_MINUS_3DB, | |
77 | LEVEL_MINUS_4POINT5DB, | |
78 | LEVEL_MINUS_6DB, | |
79 | LEVEL_ZERO, | |
80 | LEVEL_MINUS_9DB | |
81 | }; | |
82 | ||
83 | /** Adjustments in dB gain (LFE, +10 to -21 dB) */ | |
84 | static const float gain_levels_lfe[32] = { | |
85 | 3.162275, 2.818382, 2.511886, 2.238719, 1.995261, 1.778278, 1.584893, | |
86 | 1.412536, 1.258924, 1.122018, 1.000000, 0.891251, 0.794328, 0.707946, | |
87 | 0.630957, 0.562341, 0.501187, 0.446683, 0.398107, 0.354813, 0.316227, | |
88 | 0.281838, 0.251188, 0.223872, 0.199526, 0.177828, 0.158489, 0.141253, | |
89 | 0.125892, 0.112201, 0.100000, 0.089125 | |
90 | }; | |
91 | ||
92 | /** | |
93 | * Table for default stereo downmixing coefficients | |
94 | * reference: Section 7.8.2 Downmixing Into Two Channels | |
95 | */ | |
96 | static const uint8_t ac3_default_coeffs[8][5][2] = { | |
97 | { { 2, 7 }, { 7, 2 }, }, | |
98 | { { 4, 4 }, }, | |
99 | { { 2, 7 }, { 7, 2 }, }, | |
100 | { { 2, 7 }, { 5, 5 }, { 7, 2 }, }, | |
101 | { { 2, 7 }, { 7, 2 }, { 6, 6 }, }, | |
102 | { { 2, 7 }, { 5, 5 }, { 7, 2 }, { 8, 8 }, }, | |
103 | { { 2, 7 }, { 7, 2 }, { 6, 7 }, { 7, 6 }, }, | |
104 | { { 2, 7 }, { 5, 5 }, { 7, 2 }, { 6, 7 }, { 7, 6 }, }, | |
105 | }; | |
106 | ||
107 | /** | |
108 | * Symmetrical Dequantization | |
109 | * reference: Section 7.3.3 Expansion of Mantissas for Symmetrical Quantization | |
110 | * Tables 7.19 to 7.23 | |
111 | */ | |
112 | static inline int | |
113 | symmetric_dequant(int code, int levels) | |
114 | { | |
115 | return ((code - (levels >> 1)) << 24) / levels; | |
116 | } | |
117 | ||
118 | /* | |
119 | * Initialize tables at runtime. | |
120 | */ | |
121 | static av_cold void ac3_tables_init(void) | |
122 | { | |
123 | int i; | |
124 | ||
125 | /* generate table for ungrouping 3 values in 7 bits | |
126 | reference: Section 7.1.3 Exponent Decoding */ | |
127 | for (i = 0; i < 128; i++) { | |
128 | ungroup_3_in_7_bits_tab[i][0] = i / 25; | |
129 | ungroup_3_in_7_bits_tab[i][1] = (i % 25) / 5; | |
130 | ungroup_3_in_7_bits_tab[i][2] = (i % 25) % 5; | |
131 | } | |
132 | ||
133 | /* generate grouped mantissa tables | |
134 | reference: Section 7.3.5 Ungrouping of Mantissas */ | |
135 | for (i = 0; i < 32; i++) { | |
136 | /* bap=1 mantissas */ | |
137 | b1_mantissas[i][0] = symmetric_dequant(ff_ac3_ungroup_3_in_5_bits_tab[i][0], 3); | |
138 | b1_mantissas[i][1] = symmetric_dequant(ff_ac3_ungroup_3_in_5_bits_tab[i][1], 3); | |
139 | b1_mantissas[i][2] = symmetric_dequant(ff_ac3_ungroup_3_in_5_bits_tab[i][2], 3); | |
140 | } | |
141 | for (i = 0; i < 128; i++) { | |
142 | /* bap=2 mantissas */ | |
143 | b2_mantissas[i][0] = symmetric_dequant(ungroup_3_in_7_bits_tab[i][0], 5); | |
144 | b2_mantissas[i][1] = symmetric_dequant(ungroup_3_in_7_bits_tab[i][1], 5); | |
145 | b2_mantissas[i][2] = symmetric_dequant(ungroup_3_in_7_bits_tab[i][2], 5); | |
146 | ||
147 | /* bap=4 mantissas */ | |
148 | b4_mantissas[i][0] = symmetric_dequant(i / 11, 11); | |
149 | b4_mantissas[i][1] = symmetric_dequant(i % 11, 11); | |
150 | } | |
151 | /* generate ungrouped mantissa tables | |
152 | reference: Tables 7.21 and 7.23 */ | |
153 | for (i = 0; i < 7; i++) { | |
154 | /* bap=3 mantissas */ | |
155 | b3_mantissas[i] = symmetric_dequant(i, 7); | |
156 | } | |
157 | for (i = 0; i < 15; i++) { | |
158 | /* bap=5 mantissas */ | |
159 | b5_mantissas[i] = symmetric_dequant(i, 15); | |
160 | } | |
161 | ||
162 | /* generate dynamic range table | |
163 | reference: Section 7.7.1 Dynamic Range Control */ | |
164 | for (i = 0; i < 256; i++) { | |
165 | int v = (i >> 5) - ((i >> 7) << 3) - 5; | |
166 | dynamic_range_tab[i] = powf(2.0f, v) * ((i & 0x1F) | 0x20); | |
167 | } | |
168 | ||
169 | /* generate compr dynamic range table | |
170 | reference: Section 7.7.2 Heavy Compression */ | |
171 | for (i = 0; i < 256; i++) { | |
172 | int v = (i >> 4) - ((i >> 7) << 4) - 4; | |
173 | heavy_dynamic_range_tab[i] = powf(2.0f, v) * ((i & 0xF) | 0x10); | |
174 | } | |
175 | ||
176 | } | |
177 | ||
178 | /** | |
179 | * AVCodec initialization | |
180 | */ | |
181 | static av_cold int ac3_decode_init(AVCodecContext *avctx) | |
182 | { | |
183 | AC3DecodeContext *s = avctx->priv_data; | |
184 | int i; | |
185 | ||
186 | s->avctx = avctx; | |
187 | ||
188 | ff_ac3_common_init(); | |
189 | ac3_tables_init(); | |
190 | ff_mdct_init(&s->imdct_256, 8, 1, 1.0); | |
191 | ff_mdct_init(&s->imdct_512, 9, 1, 1.0); | |
192 | AC3_RENAME(ff_kbd_window_init)(s->window, 5.0, 256); | |
193 | ff_bswapdsp_init(&s->bdsp); | |
194 | ||
195 | #if (USE_FIXED) | |
196 | s->fdsp = avpriv_alloc_fixed_dsp(avctx->flags & CODEC_FLAG_BITEXACT); | |
197 | #else | |
f6fa7814 | 198 | s->fdsp = avpriv_float_dsp_alloc(avctx->flags & CODEC_FLAG_BITEXACT); |
2ba45a60 DM |
199 | #endif |
200 | ||
201 | ff_ac3dsp_init(&s->ac3dsp, avctx->flags & CODEC_FLAG_BITEXACT); | |
202 | ff_fmt_convert_init(&s->fmt_conv, avctx); | |
203 | av_lfg_init(&s->dith_state, 0); | |
204 | ||
205 | if (USE_FIXED) | |
206 | avctx->sample_fmt = AV_SAMPLE_FMT_S16P; | |
207 | else | |
208 | avctx->sample_fmt = AV_SAMPLE_FMT_FLTP; | |
209 | ||
210 | /* allow downmixing to stereo or mono */ | |
211 | #if FF_API_REQUEST_CHANNELS | |
212 | FF_DISABLE_DEPRECATION_WARNINGS | |
213 | if (avctx->request_channels == 1) | |
214 | avctx->request_channel_layout = AV_CH_LAYOUT_MONO; | |
215 | else if (avctx->request_channels == 2) | |
216 | avctx->request_channel_layout = AV_CH_LAYOUT_STEREO; | |
217 | FF_ENABLE_DEPRECATION_WARNINGS | |
218 | #endif | |
219 | if (avctx->channels > 1 && | |
220 | avctx->request_channel_layout == AV_CH_LAYOUT_MONO) | |
221 | avctx->channels = 1; | |
222 | else if (avctx->channels > 2 && | |
223 | avctx->request_channel_layout == AV_CH_LAYOUT_STEREO) | |
224 | avctx->channels = 2; | |
225 | s->downmixed = 1; | |
226 | ||
227 | for (i = 0; i < AC3_MAX_CHANNELS; i++) { | |
228 | s->xcfptr[i] = s->transform_coeffs[i]; | |
229 | s->dlyptr[i] = s->delay[i]; | |
230 | } | |
231 | ||
232 | return 0; | |
233 | } | |
234 | ||
235 | /** | |
236 | * Parse the 'sync info' and 'bit stream info' from the AC-3 bitstream. | |
237 | * GetBitContext within AC3DecodeContext must point to | |
238 | * the start of the synchronized AC-3 bitstream. | |
239 | */ | |
240 | static int ac3_parse_header(AC3DecodeContext *s) | |
241 | { | |
242 | GetBitContext *gbc = &s->gbc; | |
243 | int i; | |
244 | ||
245 | /* read the rest of the bsi. read twice for dual mono mode. */ | |
246 | i = !s->channel_mode; | |
247 | do { | |
248 | s->dialog_normalization[(!s->channel_mode)-i] = -get_bits(gbc, 5); | |
249 | if (s->dialog_normalization[(!s->channel_mode)-i] == 0) { | |
250 | s->dialog_normalization[(!s->channel_mode)-i] = -31; | |
251 | } | |
252 | if (s->target_level != 0) { | |
253 | s->level_gain[(!s->channel_mode)-i] = powf(2.0f, | |
254 | (float)(s->target_level - | |
255 | s->dialog_normalization[(!s->channel_mode)-i])/6.0f); | |
256 | } | |
257 | if (s->compression_exists[(!s->channel_mode)-i] = get_bits1(gbc)) { | |
258 | s->heavy_dynamic_range[(!s->channel_mode)-i] = | |
259 | AC3_HEAVY_RANGE(get_bits(gbc, 8)); | |
260 | } | |
261 | if (get_bits1(gbc)) | |
262 | skip_bits(gbc, 8); //skip language code | |
263 | if (get_bits1(gbc)) | |
264 | skip_bits(gbc, 7); //skip audio production information | |
265 | } while (i--); | |
266 | ||
267 | skip_bits(gbc, 2); //skip copyright bit and original bitstream bit | |
268 | ||
269 | /* skip the timecodes or parse the Alternate Bit Stream Syntax */ | |
270 | if (s->bitstream_id != 6) { | |
271 | if (get_bits1(gbc)) | |
272 | skip_bits(gbc, 14); //skip timecode1 | |
273 | if (get_bits1(gbc)) | |
274 | skip_bits(gbc, 14); //skip timecode2 | |
275 | } else { | |
276 | if (get_bits1(gbc)) { | |
277 | s->preferred_downmix = get_bits(gbc, 2); | |
278 | s->center_mix_level_ltrt = get_bits(gbc, 3); | |
279 | s->surround_mix_level_ltrt = av_clip(get_bits(gbc, 3), 3, 7); | |
280 | s->center_mix_level = get_bits(gbc, 3); | |
281 | s->surround_mix_level = av_clip(get_bits(gbc, 3), 3, 7); | |
282 | } | |
283 | if (get_bits1(gbc)) { | |
284 | s->dolby_surround_ex_mode = get_bits(gbc, 2); | |
285 | s->dolby_headphone_mode = get_bits(gbc, 2); | |
286 | skip_bits(gbc, 10); // skip adconvtyp (1), xbsi2 (8), encinfo (1) | |
287 | } | |
288 | } | |
289 | ||
290 | /* skip additional bitstream info */ | |
291 | if (get_bits1(gbc)) { | |
292 | i = get_bits(gbc, 6); | |
293 | do { | |
294 | skip_bits(gbc, 8); | |
295 | } while (i--); | |
296 | } | |
297 | ||
298 | return 0; | |
299 | } | |
300 | ||
301 | /** | |
302 | * Common function to parse AC-3 or E-AC-3 frame header | |
303 | */ | |
304 | static int parse_frame_header(AC3DecodeContext *s) | |
305 | { | |
306 | AC3HeaderInfo hdr, *phdr=&hdr; | |
307 | int err; | |
308 | ||
309 | err = avpriv_ac3_parse_header2(&s->gbc, &phdr); | |
310 | if (err) | |
311 | return err; | |
312 | ||
313 | /* get decoding parameters from header info */ | |
314 | s->bit_alloc_params.sr_code = hdr.sr_code; | |
315 | s->bitstream_id = hdr.bitstream_id; | |
316 | s->bitstream_mode = hdr.bitstream_mode; | |
317 | s->channel_mode = hdr.channel_mode; | |
318 | s->lfe_on = hdr.lfe_on; | |
319 | s->bit_alloc_params.sr_shift = hdr.sr_shift; | |
320 | s->sample_rate = hdr.sample_rate; | |
321 | s->bit_rate = hdr.bit_rate; | |
322 | s->channels = hdr.channels; | |
323 | s->fbw_channels = s->channels - s->lfe_on; | |
324 | s->lfe_ch = s->fbw_channels + 1; | |
325 | s->frame_size = hdr.frame_size; | |
326 | s->preferred_downmix = AC3_DMIXMOD_NOTINDICATED; | |
327 | s->center_mix_level = hdr.center_mix_level; | |
328 | s->center_mix_level_ltrt = 4; // -3.0dB | |
329 | s->surround_mix_level = hdr.surround_mix_level; | |
330 | s->surround_mix_level_ltrt = 4; // -3.0dB | |
331 | s->lfe_mix_level_exists = 0; | |
332 | s->num_blocks = hdr.num_blocks; | |
333 | s->frame_type = hdr.frame_type; | |
334 | s->substreamid = hdr.substreamid; | |
335 | s->dolby_surround_mode = hdr.dolby_surround_mode; | |
336 | s->dolby_surround_ex_mode = AC3_DSUREXMOD_NOTINDICATED; | |
337 | s->dolby_headphone_mode = AC3_DHEADPHONMOD_NOTINDICATED; | |
338 | ||
339 | if (s->lfe_on) { | |
340 | s->start_freq[s->lfe_ch] = 0; | |
341 | s->end_freq[s->lfe_ch] = 7; | |
342 | s->num_exp_groups[s->lfe_ch] = 2; | |
343 | s->channel_in_cpl[s->lfe_ch] = 0; | |
344 | } | |
345 | ||
346 | if (s->bitstream_id <= 10) { | |
347 | s->eac3 = 0; | |
348 | s->snr_offset_strategy = 2; | |
349 | s->block_switch_syntax = 1; | |
350 | s->dither_flag_syntax = 1; | |
351 | s->bit_allocation_syntax = 1; | |
352 | s->fast_gain_syntax = 0; | |
353 | s->first_cpl_leak = 0; | |
354 | s->dba_syntax = 1; | |
355 | s->skip_syntax = 1; | |
356 | memset(s->channel_uses_aht, 0, sizeof(s->channel_uses_aht)); | |
357 | return ac3_parse_header(s); | |
358 | } else if (CONFIG_EAC3_DECODER) { | |
359 | s->eac3 = 1; | |
360 | return ff_eac3_parse_header(s); | |
361 | } else { | |
362 | av_log(s->avctx, AV_LOG_ERROR, "E-AC-3 support not compiled in\n"); | |
363 | return AVERROR(ENOSYS); | |
364 | } | |
365 | } | |
366 | ||
367 | /** | |
368 | * Set stereo downmixing coefficients based on frame header info. | |
369 | * reference: Section 7.8.2 Downmixing Into Two Channels | |
370 | */ | |
371 | static void set_downmix_coeffs(AC3DecodeContext *s) | |
372 | { | |
373 | int i; | |
374 | float cmix = gain_levels[s-> center_mix_level]; | |
375 | float smix = gain_levels[s->surround_mix_level]; | |
376 | float norm0, norm1; | |
377 | float downmix_coeffs[AC3_MAX_CHANNELS][2]; | |
378 | ||
379 | for (i = 0; i < s->fbw_channels; i++) { | |
380 | downmix_coeffs[i][0] = gain_levels[ac3_default_coeffs[s->channel_mode][i][0]]; | |
381 | downmix_coeffs[i][1] = gain_levels[ac3_default_coeffs[s->channel_mode][i][1]]; | |
382 | } | |
383 | if (s->channel_mode > 1 && s->channel_mode & 1) { | |
384 | downmix_coeffs[1][0] = downmix_coeffs[1][1] = cmix; | |
385 | } | |
386 | if (s->channel_mode == AC3_CHMODE_2F1R || s->channel_mode == AC3_CHMODE_3F1R) { | |
387 | int nf = s->channel_mode - 2; | |
388 | downmix_coeffs[nf][0] = downmix_coeffs[nf][1] = smix * LEVEL_MINUS_3DB; | |
389 | } | |
390 | if (s->channel_mode == AC3_CHMODE_2F2R || s->channel_mode == AC3_CHMODE_3F2R) { | |
391 | int nf = s->channel_mode - 4; | |
392 | downmix_coeffs[nf][0] = downmix_coeffs[nf+1][1] = smix; | |
393 | } | |
394 | ||
395 | /* renormalize */ | |
396 | norm0 = norm1 = 0.0; | |
397 | for (i = 0; i < s->fbw_channels; i++) { | |
398 | norm0 += downmix_coeffs[i][0]; | |
399 | norm1 += downmix_coeffs[i][1]; | |
400 | } | |
401 | norm0 = 1.0f / norm0; | |
402 | norm1 = 1.0f / norm1; | |
403 | for (i = 0; i < s->fbw_channels; i++) { | |
404 | downmix_coeffs[i][0] *= norm0; | |
405 | downmix_coeffs[i][1] *= norm1; | |
406 | } | |
407 | ||
408 | if (s->output_mode == AC3_CHMODE_MONO) { | |
409 | for (i = 0; i < s->fbw_channels; i++) | |
410 | downmix_coeffs[i][0] = (downmix_coeffs[i][0] + | |
411 | downmix_coeffs[i][1]) * LEVEL_MINUS_3DB; | |
412 | } | |
413 | for (i = 0; i < s->fbw_channels; i++) { | |
414 | s->downmix_coeffs[i][0] = FIXR12(downmix_coeffs[i][0]); | |
415 | s->downmix_coeffs[i][1] = FIXR12(downmix_coeffs[i][1]); | |
416 | } | |
417 | } | |
418 | ||
419 | /** | |
420 | * Decode the grouped exponents according to exponent strategy. | |
421 | * reference: Section 7.1.3 Exponent Decoding | |
422 | */ | |
423 | static int decode_exponents(GetBitContext *gbc, int exp_strategy, int ngrps, | |
424 | uint8_t absexp, int8_t *dexps) | |
425 | { | |
426 | int i, j, grp, group_size; | |
427 | int dexp[256]; | |
428 | int expacc, prevexp; | |
429 | ||
430 | /* unpack groups */ | |
431 | group_size = exp_strategy + (exp_strategy == EXP_D45); | |
432 | for (grp = 0, i = 0; grp < ngrps; grp++) { | |
433 | expacc = get_bits(gbc, 7); | |
434 | dexp[i++] = ungroup_3_in_7_bits_tab[expacc][0]; | |
435 | dexp[i++] = ungroup_3_in_7_bits_tab[expacc][1]; | |
436 | dexp[i++] = ungroup_3_in_7_bits_tab[expacc][2]; | |
437 | } | |
438 | ||
439 | /* convert to absolute exps and expand groups */ | |
440 | prevexp = absexp; | |
441 | for (i = 0, j = 0; i < ngrps * 3; i++) { | |
442 | prevexp += dexp[i] - 2; | |
443 | if (prevexp > 24U) | |
444 | return -1; | |
445 | switch (group_size) { | |
446 | case 4: dexps[j++] = prevexp; | |
447 | dexps[j++] = prevexp; | |
448 | case 2: dexps[j++] = prevexp; | |
449 | case 1: dexps[j++] = prevexp; | |
450 | } | |
451 | } | |
452 | return 0; | |
453 | } | |
454 | ||
455 | /** | |
456 | * Generate transform coefficients for each coupled channel in the coupling | |
457 | * range using the coupling coefficients and coupling coordinates. | |
458 | * reference: Section 7.4.3 Coupling Coordinate Format | |
459 | */ | |
460 | static void calc_transform_coeffs_cpl(AC3DecodeContext *s) | |
461 | { | |
462 | int bin, band, ch; | |
463 | ||
464 | bin = s->start_freq[CPL_CH]; | |
465 | for (band = 0; band < s->num_cpl_bands; band++) { | |
466 | int band_start = bin; | |
467 | int band_end = bin + s->cpl_band_sizes[band]; | |
468 | for (ch = 1; ch <= s->fbw_channels; ch++) { | |
469 | if (s->channel_in_cpl[ch]) { | |
470 | int cpl_coord = s->cpl_coords[ch][band] << 5; | |
471 | for (bin = band_start; bin < band_end; bin++) { | |
472 | s->fixed_coeffs[ch][bin] = | |
473 | MULH(s->fixed_coeffs[CPL_CH][bin] << 4, cpl_coord); | |
474 | } | |
475 | if (ch == 2 && s->phase_flags[band]) { | |
476 | for (bin = band_start; bin < band_end; bin++) | |
477 | s->fixed_coeffs[2][bin] = -s->fixed_coeffs[2][bin]; | |
478 | } | |
479 | } | |
480 | } | |
481 | bin = band_end; | |
482 | } | |
483 | } | |
484 | ||
485 | /** | |
486 | * Grouped mantissas for 3-level 5-level and 11-level quantization | |
487 | */ | |
488 | typedef struct { | |
489 | int b1_mant[2]; | |
490 | int b2_mant[2]; | |
491 | int b4_mant; | |
492 | int b1; | |
493 | int b2; | |
494 | int b4; | |
495 | } mant_groups; | |
496 | ||
497 | /** | |
498 | * Decode the transform coefficients for a particular channel | |
499 | * reference: Section 7.3 Quantization and Decoding of Mantissas | |
500 | */ | |
501 | static void ac3_decode_transform_coeffs_ch(AC3DecodeContext *s, int ch_index, mant_groups *m) | |
502 | { | |
503 | int start_freq = s->start_freq[ch_index]; | |
504 | int end_freq = s->end_freq[ch_index]; | |
505 | uint8_t *baps = s->bap[ch_index]; | |
506 | int8_t *exps = s->dexps[ch_index]; | |
507 | int32_t *coeffs = s->fixed_coeffs[ch_index]; | |
508 | int dither = (ch_index == CPL_CH) || s->dither_flag[ch_index]; | |
509 | GetBitContext *gbc = &s->gbc; | |
510 | int freq; | |
511 | ||
512 | for (freq = start_freq; freq < end_freq; freq++) { | |
513 | int bap = baps[freq]; | |
514 | int mantissa; | |
515 | switch (bap) { | |
516 | case 0: | |
517 | /* random noise with approximate range of -0.707 to 0.707 */ | |
518 | if (dither) | |
519 | mantissa = (((av_lfg_get(&s->dith_state)>>8)*181)>>8) - 5931008; | |
520 | else | |
521 | mantissa = 0; | |
522 | break; | |
523 | case 1: | |
524 | if (m->b1) { | |
525 | m->b1--; | |
526 | mantissa = m->b1_mant[m->b1]; | |
527 | } else { | |
528 | int bits = get_bits(gbc, 5); | |
529 | mantissa = b1_mantissas[bits][0]; | |
530 | m->b1_mant[1] = b1_mantissas[bits][1]; | |
531 | m->b1_mant[0] = b1_mantissas[bits][2]; | |
532 | m->b1 = 2; | |
533 | } | |
534 | break; | |
535 | case 2: | |
536 | if (m->b2) { | |
537 | m->b2--; | |
538 | mantissa = m->b2_mant[m->b2]; | |
539 | } else { | |
540 | int bits = get_bits(gbc, 7); | |
541 | mantissa = b2_mantissas[bits][0]; | |
542 | m->b2_mant[1] = b2_mantissas[bits][1]; | |
543 | m->b2_mant[0] = b2_mantissas[bits][2]; | |
544 | m->b2 = 2; | |
545 | } | |
546 | break; | |
547 | case 3: | |
548 | mantissa = b3_mantissas[get_bits(gbc, 3)]; | |
549 | break; | |
550 | case 4: | |
551 | if (m->b4) { | |
552 | m->b4 = 0; | |
553 | mantissa = m->b4_mant; | |
554 | } else { | |
555 | int bits = get_bits(gbc, 7); | |
556 | mantissa = b4_mantissas[bits][0]; | |
557 | m->b4_mant = b4_mantissas[bits][1]; | |
558 | m->b4 = 1; | |
559 | } | |
560 | break; | |
561 | case 5: | |
562 | mantissa = b5_mantissas[get_bits(gbc, 4)]; | |
563 | break; | |
564 | default: /* 6 to 15 */ | |
565 | /* Shift mantissa and sign-extend it. */ | |
566 | if (bap > 15) { | |
567 | av_log(s->avctx, AV_LOG_ERROR, "bap %d is invalid in plain AC-3\n", bap); | |
568 | bap = 15; | |
569 | } | |
570 | mantissa = get_sbits(gbc, quantization_tab[bap]); | |
571 | mantissa <<= 24 - quantization_tab[bap]; | |
572 | break; | |
573 | } | |
574 | coeffs[freq] = mantissa >> exps[freq]; | |
575 | } | |
576 | } | |
577 | ||
578 | /** | |
579 | * Remove random dithering from coupling range coefficients with zero-bit | |
580 | * mantissas for coupled channels which do not use dithering. | |
581 | * reference: Section 7.3.4 Dither for Zero Bit Mantissas (bap=0) | |
582 | */ | |
583 | static void remove_dithering(AC3DecodeContext *s) { | |
584 | int ch, i; | |
585 | ||
586 | for (ch = 1; ch <= s->fbw_channels; ch++) { | |
587 | if (!s->dither_flag[ch] && s->channel_in_cpl[ch]) { | |
588 | for (i = s->start_freq[CPL_CH]; i < s->end_freq[CPL_CH]; i++) { | |
589 | if (!s->bap[CPL_CH][i]) | |
590 | s->fixed_coeffs[ch][i] = 0; | |
591 | } | |
592 | } | |
593 | } | |
594 | } | |
595 | ||
596 | static void decode_transform_coeffs_ch(AC3DecodeContext *s, int blk, int ch, | |
597 | mant_groups *m) | |
598 | { | |
599 | if (!s->channel_uses_aht[ch]) { | |
600 | ac3_decode_transform_coeffs_ch(s, ch, m); | |
601 | } else { | |
602 | /* if AHT is used, mantissas for all blocks are encoded in the first | |
603 | block of the frame. */ | |
604 | int bin; | |
605 | if (!blk && CONFIG_EAC3_DECODER) | |
606 | ff_eac3_decode_transform_coeffs_aht_ch(s, ch); | |
607 | for (bin = s->start_freq[ch]; bin < s->end_freq[ch]; bin++) { | |
608 | s->fixed_coeffs[ch][bin] = s->pre_mantissa[ch][bin][blk] >> s->dexps[ch][bin]; | |
609 | } | |
610 | } | |
611 | } | |
612 | ||
613 | /** | |
614 | * Decode the transform coefficients. | |
615 | */ | |
616 | static void decode_transform_coeffs(AC3DecodeContext *s, int blk) | |
617 | { | |
618 | int ch, end; | |
619 | int got_cplchan = 0; | |
620 | mant_groups m; | |
621 | ||
622 | m.b1 = m.b2 = m.b4 = 0; | |
623 | ||
624 | for (ch = 1; ch <= s->channels; ch++) { | |
625 | /* transform coefficients for full-bandwidth channel */ | |
626 | decode_transform_coeffs_ch(s, blk, ch, &m); | |
627 | /* transform coefficients for coupling channel come right after the | |
628 | coefficients for the first coupled channel*/ | |
629 | if (s->channel_in_cpl[ch]) { | |
630 | if (!got_cplchan) { | |
631 | decode_transform_coeffs_ch(s, blk, CPL_CH, &m); | |
632 | calc_transform_coeffs_cpl(s); | |
633 | got_cplchan = 1; | |
634 | } | |
635 | end = s->end_freq[CPL_CH]; | |
636 | } else { | |
637 | end = s->end_freq[ch]; | |
638 | } | |
639 | do | |
640 | s->fixed_coeffs[ch][end] = 0; | |
641 | while (++end < 256); | |
642 | } | |
643 | ||
644 | /* zero the dithered coefficients for appropriate channels */ | |
645 | remove_dithering(s); | |
646 | } | |
647 | ||
648 | /** | |
649 | * Stereo rematrixing. | |
650 | * reference: Section 7.5.4 Rematrixing : Decoding Technique | |
651 | */ | |
652 | static void do_rematrixing(AC3DecodeContext *s) | |
653 | { | |
654 | int bnd, i; | |
655 | int end, bndend; | |
656 | ||
657 | end = FFMIN(s->end_freq[1], s->end_freq[2]); | |
658 | ||
659 | for (bnd = 0; bnd < s->num_rematrixing_bands; bnd++) { | |
660 | if (s->rematrixing_flags[bnd]) { | |
661 | bndend = FFMIN(end, ff_ac3_rematrix_band_tab[bnd + 1]); | |
662 | for (i = ff_ac3_rematrix_band_tab[bnd]; i < bndend; i++) { | |
663 | int tmp0 = s->fixed_coeffs[1][i]; | |
664 | s->fixed_coeffs[1][i] += s->fixed_coeffs[2][i]; | |
665 | s->fixed_coeffs[2][i] = tmp0 - s->fixed_coeffs[2][i]; | |
666 | } | |
667 | } | |
668 | } | |
669 | } | |
670 | ||
671 | /** | |
672 | * Inverse MDCT Transform. | |
673 | * Convert frequency domain coefficients to time-domain audio samples. | |
674 | * reference: Section 7.9.4 Transformation Equations | |
675 | */ | |
676 | static inline void do_imdct(AC3DecodeContext *s, int channels) | |
677 | { | |
678 | int ch; | |
679 | ||
680 | for (ch = 1; ch <= channels; ch++) { | |
681 | if (s->block_switch[ch]) { | |
682 | int i; | |
683 | FFTSample *x = s->tmp_output + 128; | |
684 | for (i = 0; i < 128; i++) | |
685 | x[i] = s->transform_coeffs[ch][2 * i]; | |
686 | s->imdct_256.imdct_half(&s->imdct_256, s->tmp_output, x); | |
687 | #if USE_FIXED | |
688 | s->fdsp->vector_fmul_window_scaled(s->outptr[ch - 1], s->delay[ch - 1], | |
689 | s->tmp_output, s->window, 128, 8); | |
690 | #else | |
f6fa7814 | 691 | s->fdsp->vector_fmul_window(s->outptr[ch - 1], s->delay[ch - 1], |
2ba45a60 DM |
692 | s->tmp_output, s->window, 128); |
693 | #endif | |
694 | for (i = 0; i < 128; i++) | |
695 | x[i] = s->transform_coeffs[ch][2 * i + 1]; | |
696 | s->imdct_256.imdct_half(&s->imdct_256, s->delay[ch - 1], x); | |
697 | } else { | |
698 | s->imdct_512.imdct_half(&s->imdct_512, s->tmp_output, s->transform_coeffs[ch]); | |
699 | #if USE_FIXED | |
700 | s->fdsp->vector_fmul_window_scaled(s->outptr[ch - 1], s->delay[ch - 1], | |
701 | s->tmp_output, s->window, 128, 8); | |
702 | #else | |
f6fa7814 | 703 | s->fdsp->vector_fmul_window(s->outptr[ch - 1], s->delay[ch - 1], |
2ba45a60 DM |
704 | s->tmp_output, s->window, 128); |
705 | #endif | |
706 | memcpy(s->delay[ch - 1], s->tmp_output + 128, 128 * sizeof(FFTSample)); | |
707 | } | |
708 | } | |
709 | } | |
710 | ||
711 | /** | |
712 | * Upmix delay samples from stereo to original channel layout. | |
713 | */ | |
714 | static void ac3_upmix_delay(AC3DecodeContext *s) | |
715 | { | |
716 | int channel_data_size = sizeof(s->delay[0]); | |
717 | switch (s->channel_mode) { | |
718 | case AC3_CHMODE_DUALMONO: | |
719 | case AC3_CHMODE_STEREO: | |
720 | /* upmix mono to stereo */ | |
721 | memcpy(s->delay[1], s->delay[0], channel_data_size); | |
722 | break; | |
723 | case AC3_CHMODE_2F2R: | |
724 | memset(s->delay[3], 0, channel_data_size); | |
725 | case AC3_CHMODE_2F1R: | |
726 | memset(s->delay[2], 0, channel_data_size); | |
727 | break; | |
728 | case AC3_CHMODE_3F2R: | |
729 | memset(s->delay[4], 0, channel_data_size); | |
730 | case AC3_CHMODE_3F1R: | |
731 | memset(s->delay[3], 0, channel_data_size); | |
732 | case AC3_CHMODE_3F: | |
733 | memcpy(s->delay[2], s->delay[1], channel_data_size); | |
734 | memset(s->delay[1], 0, channel_data_size); | |
735 | break; | |
736 | } | |
737 | } | |
738 | ||
739 | /** | |
740 | * Decode band structure for coupling, spectral extension, or enhanced coupling. | |
741 | * The band structure defines how many subbands are in each band. For each | |
742 | * subband in the range, 1 means it is combined with the previous band, and 0 | |
743 | * means that it starts a new band. | |
744 | * | |
745 | * @param[in] gbc bit reader context | |
746 | * @param[in] blk block number | |
747 | * @param[in] eac3 flag to indicate E-AC-3 | |
748 | * @param[in] ecpl flag to indicate enhanced coupling | |
749 | * @param[in] start_subband subband number for start of range | |
750 | * @param[in] end_subband subband number for end of range | |
751 | * @param[in] default_band_struct default band structure table | |
752 | * @param[out] num_bands number of bands (optionally NULL) | |
753 | * @param[out] band_sizes array containing the number of bins in each band (optionally NULL) | |
754 | */ | |
755 | static void decode_band_structure(GetBitContext *gbc, int blk, int eac3, | |
756 | int ecpl, int start_subband, int end_subband, | |
757 | const uint8_t *default_band_struct, | |
758 | int *num_bands, uint8_t *band_sizes) | |
759 | { | |
760 | int subbnd, bnd, n_subbands, n_bands=0; | |
761 | uint8_t bnd_sz[22]; | |
762 | uint8_t coded_band_struct[22]; | |
763 | const uint8_t *band_struct; | |
764 | ||
765 | n_subbands = end_subband - start_subband; | |
766 | ||
767 | /* decode band structure from bitstream or use default */ | |
768 | if (!eac3 || get_bits1(gbc)) { | |
769 | for (subbnd = 0; subbnd < n_subbands - 1; subbnd++) { | |
770 | coded_band_struct[subbnd] = get_bits1(gbc); | |
771 | } | |
772 | band_struct = coded_band_struct; | |
773 | } else if (!blk) { | |
774 | band_struct = &default_band_struct[start_subband+1]; | |
775 | } else { | |
776 | /* no change in band structure */ | |
777 | return; | |
778 | } | |
779 | ||
780 | /* calculate number of bands and band sizes based on band structure. | |
781 | note that the first 4 subbands in enhanced coupling span only 6 bins | |
782 | instead of 12. */ | |
783 | if (num_bands || band_sizes ) { | |
784 | n_bands = n_subbands; | |
785 | bnd_sz[0] = ecpl ? 6 : 12; | |
786 | for (bnd = 0, subbnd = 1; subbnd < n_subbands; subbnd++) { | |
787 | int subbnd_size = (ecpl && subbnd < 4) ? 6 : 12; | |
788 | if (band_struct[subbnd - 1]) { | |
789 | n_bands--; | |
790 | bnd_sz[bnd] += subbnd_size; | |
791 | } else { | |
792 | bnd_sz[++bnd] = subbnd_size; | |
793 | } | |
794 | } | |
795 | } | |
796 | ||
797 | /* set optional output params */ | |
798 | if (num_bands) | |
799 | *num_bands = n_bands; | |
800 | if (band_sizes) | |
801 | memcpy(band_sizes, bnd_sz, n_bands); | |
802 | } | |
803 | ||
804 | /** | |
805 | * Decode a single audio block from the AC-3 bitstream. | |
806 | */ | |
807 | static int decode_audio_block(AC3DecodeContext *s, int blk) | |
808 | { | |
809 | int fbw_channels = s->fbw_channels; | |
810 | int channel_mode = s->channel_mode; | |
811 | int i, bnd, seg, ch; | |
812 | int different_transforms; | |
813 | int downmix_output; | |
814 | int cpl_in_use; | |
815 | GetBitContext *gbc = &s->gbc; | |
816 | uint8_t bit_alloc_stages[AC3_MAX_CHANNELS] = { 0 }; | |
817 | ||
818 | /* block switch flags */ | |
819 | different_transforms = 0; | |
820 | if (s->block_switch_syntax) { | |
821 | for (ch = 1; ch <= fbw_channels; ch++) { | |
822 | s->block_switch[ch] = get_bits1(gbc); | |
823 | if (ch > 1 && s->block_switch[ch] != s->block_switch[1]) | |
824 | different_transforms = 1; | |
825 | } | |
826 | } | |
827 | ||
828 | /* dithering flags */ | |
829 | if (s->dither_flag_syntax) { | |
830 | for (ch = 1; ch <= fbw_channels; ch++) { | |
831 | s->dither_flag[ch] = get_bits1(gbc); | |
832 | } | |
833 | } | |
834 | ||
835 | /* dynamic range */ | |
836 | i = !s->channel_mode; | |
837 | do { | |
838 | if (get_bits1(gbc)) { | |
839 | /* Allow asymmetric application of DRC when drc_scale > 1. | |
840 | Amplification of quiet sounds is enhanced */ | |
841 | int range_bits = get_bits(gbc, 8); | |
842 | INTFLOAT range = AC3_RANGE(range_bits); | |
843 | if (range_bits <= 127 || s->drc_scale <= 1.0) | |
844 | s->dynamic_range[i] = AC3_DYNAMIC_RANGE(range); | |
845 | else | |
846 | s->dynamic_range[i] = range; | |
847 | } else if (blk == 0) { | |
848 | s->dynamic_range[i] = AC3_DYNAMIC_RANGE1; | |
849 | } | |
850 | } while (i--); | |
851 | ||
852 | /* spectral extension strategy */ | |
853 | if (s->eac3 && (!blk || get_bits1(gbc))) { | |
854 | s->spx_in_use = get_bits1(gbc); | |
855 | if (s->spx_in_use) { | |
856 | int dst_start_freq, dst_end_freq, src_start_freq, | |
857 | start_subband, end_subband; | |
858 | ||
859 | /* determine which channels use spx */ | |
860 | if (s->channel_mode == AC3_CHMODE_MONO) { | |
861 | s->channel_uses_spx[1] = 1; | |
862 | } else { | |
863 | for (ch = 1; ch <= fbw_channels; ch++) | |
864 | s->channel_uses_spx[ch] = get_bits1(gbc); | |
865 | } | |
866 | ||
867 | /* get the frequency bins of the spx copy region and the spx start | |
868 | and end subbands */ | |
869 | dst_start_freq = get_bits(gbc, 2); | |
870 | start_subband = get_bits(gbc, 3) + 2; | |
871 | if (start_subband > 7) | |
872 | start_subband += start_subband - 7; | |
873 | end_subband = get_bits(gbc, 3) + 5; | |
874 | #if USE_FIXED | |
875 | s->spx_dst_end_freq = end_freq_inv_tab[end_subband]; | |
876 | #endif | |
877 | if (end_subband > 7) | |
878 | end_subband += end_subband - 7; | |
879 | dst_start_freq = dst_start_freq * 12 + 25; | |
880 | src_start_freq = start_subband * 12 + 25; | |
881 | dst_end_freq = end_subband * 12 + 25; | |
882 | ||
883 | /* check validity of spx ranges */ | |
884 | if (start_subband >= end_subband) { | |
885 | av_log(s->avctx, AV_LOG_ERROR, "invalid spectral extension " | |
886 | "range (%d >= %d)\n", start_subband, end_subband); | |
887 | return AVERROR_INVALIDDATA; | |
888 | } | |
889 | if (dst_start_freq >= src_start_freq) { | |
890 | av_log(s->avctx, AV_LOG_ERROR, "invalid spectral extension " | |
891 | "copy start bin (%d >= %d)\n", dst_start_freq, src_start_freq); | |
892 | return AVERROR_INVALIDDATA; | |
893 | } | |
894 | ||
895 | s->spx_dst_start_freq = dst_start_freq; | |
896 | s->spx_src_start_freq = src_start_freq; | |
897 | if (!USE_FIXED) | |
898 | s->spx_dst_end_freq = dst_end_freq; | |
899 | ||
900 | decode_band_structure(gbc, blk, s->eac3, 0, | |
901 | start_subband, end_subband, | |
902 | ff_eac3_default_spx_band_struct, | |
903 | &s->num_spx_bands, | |
904 | s->spx_band_sizes); | |
905 | } else { | |
906 | for (ch = 1; ch <= fbw_channels; ch++) { | |
907 | s->channel_uses_spx[ch] = 0; | |
908 | s->first_spx_coords[ch] = 1; | |
909 | } | |
910 | } | |
911 | } | |
912 | ||
913 | /* spectral extension coordinates */ | |
914 | if (s->spx_in_use) { | |
915 | for (ch = 1; ch <= fbw_channels; ch++) { | |
916 | if (s->channel_uses_spx[ch]) { | |
917 | if (s->first_spx_coords[ch] || get_bits1(gbc)) { | |
918 | INTFLOAT spx_blend; | |
919 | int bin, master_spx_coord; | |
920 | ||
921 | s->first_spx_coords[ch] = 0; | |
922 | spx_blend = AC3_SPX_BLEND(get_bits(gbc, 5)); | |
923 | master_spx_coord = get_bits(gbc, 2) * 3; | |
924 | ||
925 | bin = s->spx_src_start_freq; | |
926 | for (bnd = 0; bnd < s->num_spx_bands; bnd++) { | |
927 | int bandsize; | |
928 | int spx_coord_exp, spx_coord_mant; | |
929 | INTFLOAT nratio, sblend, nblend; | |
930 | #if USE_FIXED | |
931 | int64_t accu; | |
932 | /* calculate blending factors */ | |
933 | bandsize = s->spx_band_sizes[bnd]; | |
934 | accu = (int64_t)((bin << 23) + (bandsize << 22)) * s->spx_dst_end_freq; | |
935 | nratio = (int)(accu >> 32); | |
936 | nratio -= spx_blend << 18; | |
937 | ||
938 | if (nratio < 0) { | |
939 | nblend = 0; | |
940 | sblend = 0x800000; | |
941 | } else if (nratio > 0x7fffff) { | |
942 | nblend = 0x800000; | |
943 | sblend = 0; | |
944 | } else { | |
945 | nblend = fixed_sqrt(nratio, 23); | |
946 | accu = (int64_t)nblend * 1859775393; | |
947 | nblend = (int)((accu + (1<<29)) >> 30); | |
948 | sblend = fixed_sqrt(0x800000 - nratio, 23); | |
949 | } | |
950 | #else | |
951 | float spx_coord; | |
952 | ||
953 | /* calculate blending factors */ | |
954 | bandsize = s->spx_band_sizes[bnd]; | |
955 | nratio = ((float)((bin + (bandsize >> 1))) / s->spx_dst_end_freq) - spx_blend; | |
956 | nratio = av_clipf(nratio, 0.0f, 1.0f); | |
957 | nblend = sqrtf(3.0f * nratio); // noise is scaled by sqrt(3) | |
958 | // to give unity variance | |
959 | sblend = sqrtf(1.0f - nratio); | |
960 | #endif | |
961 | bin += bandsize; | |
962 | ||
963 | /* decode spx coordinates */ | |
964 | spx_coord_exp = get_bits(gbc, 4); | |
965 | spx_coord_mant = get_bits(gbc, 2); | |
966 | if (spx_coord_exp == 15) spx_coord_mant <<= 1; | |
967 | else spx_coord_mant += 4; | |
968 | spx_coord_mant <<= (25 - spx_coord_exp - master_spx_coord); | |
969 | ||
970 | /* multiply noise and signal blending factors by spx coordinate */ | |
971 | #if USE_FIXED | |
972 | accu = (int64_t)nblend * spx_coord_mant; | |
973 | s->spx_noise_blend[ch][bnd] = (int)((accu + (1<<22)) >> 23); | |
974 | accu = (int64_t)sblend * spx_coord_mant; | |
975 | s->spx_signal_blend[ch][bnd] = (int)((accu + (1<<22)) >> 23); | |
976 | #else | |
977 | spx_coord = spx_coord_mant * (1.0f / (1 << 23)); | |
978 | s->spx_noise_blend [ch][bnd] = nblend * spx_coord; | |
979 | s->spx_signal_blend[ch][bnd] = sblend * spx_coord; | |
980 | #endif | |
981 | } | |
982 | } | |
983 | } else { | |
984 | s->first_spx_coords[ch] = 1; | |
985 | } | |
986 | } | |
987 | } | |
988 | ||
989 | /* coupling strategy */ | |
990 | if (s->eac3 ? s->cpl_strategy_exists[blk] : get_bits1(gbc)) { | |
991 | memset(bit_alloc_stages, 3, AC3_MAX_CHANNELS); | |
992 | if (!s->eac3) | |
993 | s->cpl_in_use[blk] = get_bits1(gbc); | |
994 | if (s->cpl_in_use[blk]) { | |
995 | /* coupling in use */ | |
996 | int cpl_start_subband, cpl_end_subband; | |
997 | ||
998 | if (channel_mode < AC3_CHMODE_STEREO) { | |
999 | av_log(s->avctx, AV_LOG_ERROR, "coupling not allowed in mono or dual-mono\n"); | |
1000 | return AVERROR_INVALIDDATA; | |
1001 | } | |
1002 | ||
1003 | /* check for enhanced coupling */ | |
1004 | if (s->eac3 && get_bits1(gbc)) { | |
1005 | /* TODO: parse enhanced coupling strategy info */ | |
1006 | avpriv_request_sample(s->avctx, "Enhanced coupling"); | |
1007 | return AVERROR_PATCHWELCOME; | |
1008 | } | |
1009 | ||
1010 | /* determine which channels are coupled */ | |
1011 | if (s->eac3 && s->channel_mode == AC3_CHMODE_STEREO) { | |
1012 | s->channel_in_cpl[1] = 1; | |
1013 | s->channel_in_cpl[2] = 1; | |
1014 | } else { | |
1015 | for (ch = 1; ch <= fbw_channels; ch++) | |
1016 | s->channel_in_cpl[ch] = get_bits1(gbc); | |
1017 | } | |
1018 | ||
1019 | /* phase flags in use */ | |
1020 | if (channel_mode == AC3_CHMODE_STEREO) | |
1021 | s->phase_flags_in_use = get_bits1(gbc); | |
1022 | ||
1023 | /* coupling frequency range */ | |
1024 | cpl_start_subband = get_bits(gbc, 4); | |
1025 | cpl_end_subband = s->spx_in_use ? (s->spx_src_start_freq - 37) / 12 : | |
1026 | get_bits(gbc, 4) + 3; | |
1027 | if (cpl_start_subband >= cpl_end_subband) { | |
1028 | av_log(s->avctx, AV_LOG_ERROR, "invalid coupling range (%d >= %d)\n", | |
1029 | cpl_start_subband, cpl_end_subband); | |
1030 | return AVERROR_INVALIDDATA; | |
1031 | } | |
1032 | s->start_freq[CPL_CH] = cpl_start_subband * 12 + 37; | |
1033 | s->end_freq[CPL_CH] = cpl_end_subband * 12 + 37; | |
1034 | ||
1035 | decode_band_structure(gbc, blk, s->eac3, 0, cpl_start_subband, | |
1036 | cpl_end_subband, | |
1037 | ff_eac3_default_cpl_band_struct, | |
1038 | &s->num_cpl_bands, s->cpl_band_sizes); | |
1039 | } else { | |
1040 | /* coupling not in use */ | |
1041 | for (ch = 1; ch <= fbw_channels; ch++) { | |
1042 | s->channel_in_cpl[ch] = 0; | |
1043 | s->first_cpl_coords[ch] = 1; | |
1044 | } | |
1045 | s->first_cpl_leak = s->eac3; | |
1046 | s->phase_flags_in_use = 0; | |
1047 | } | |
1048 | } else if (!s->eac3) { | |
1049 | if (!blk) { | |
1050 | av_log(s->avctx, AV_LOG_ERROR, "new coupling strategy must " | |
1051 | "be present in block 0\n"); | |
1052 | return AVERROR_INVALIDDATA; | |
1053 | } else { | |
1054 | s->cpl_in_use[blk] = s->cpl_in_use[blk-1]; | |
1055 | } | |
1056 | } | |
1057 | cpl_in_use = s->cpl_in_use[blk]; | |
1058 | ||
1059 | /* coupling coordinates */ | |
1060 | if (cpl_in_use) { | |
1061 | int cpl_coords_exist = 0; | |
1062 | ||
1063 | for (ch = 1; ch <= fbw_channels; ch++) { | |
1064 | if (s->channel_in_cpl[ch]) { | |
1065 | if ((s->eac3 && s->first_cpl_coords[ch]) || get_bits1(gbc)) { | |
1066 | int master_cpl_coord, cpl_coord_exp, cpl_coord_mant; | |
1067 | s->first_cpl_coords[ch] = 0; | |
1068 | cpl_coords_exist = 1; | |
1069 | master_cpl_coord = 3 * get_bits(gbc, 2); | |
1070 | for (bnd = 0; bnd < s->num_cpl_bands; bnd++) { | |
1071 | cpl_coord_exp = get_bits(gbc, 4); | |
1072 | cpl_coord_mant = get_bits(gbc, 4); | |
1073 | if (cpl_coord_exp == 15) | |
1074 | s->cpl_coords[ch][bnd] = cpl_coord_mant << 22; | |
1075 | else | |
1076 | s->cpl_coords[ch][bnd] = (cpl_coord_mant + 16) << 21; | |
1077 | s->cpl_coords[ch][bnd] >>= (cpl_coord_exp + master_cpl_coord); | |
1078 | } | |
1079 | } else if (!blk) { | |
1080 | av_log(s->avctx, AV_LOG_ERROR, "new coupling coordinates must " | |
1081 | "be present in block 0\n"); | |
1082 | return AVERROR_INVALIDDATA; | |
1083 | } | |
1084 | } else { | |
1085 | /* channel not in coupling */ | |
1086 | s->first_cpl_coords[ch] = 1; | |
1087 | } | |
1088 | } | |
1089 | /* phase flags */ | |
1090 | if (channel_mode == AC3_CHMODE_STEREO && cpl_coords_exist) { | |
1091 | for (bnd = 0; bnd < s->num_cpl_bands; bnd++) { | |
1092 | s->phase_flags[bnd] = s->phase_flags_in_use? get_bits1(gbc) : 0; | |
1093 | } | |
1094 | } | |
1095 | } | |
1096 | ||
1097 | /* stereo rematrixing strategy and band structure */ | |
1098 | if (channel_mode == AC3_CHMODE_STEREO) { | |
1099 | if ((s->eac3 && !blk) || get_bits1(gbc)) { | |
1100 | s->num_rematrixing_bands = 4; | |
1101 | if (cpl_in_use && s->start_freq[CPL_CH] <= 61) { | |
1102 | s->num_rematrixing_bands -= 1 + (s->start_freq[CPL_CH] == 37); | |
1103 | } else if (s->spx_in_use && s->spx_src_start_freq <= 61) { | |
1104 | s->num_rematrixing_bands--; | |
1105 | } | |
1106 | for (bnd = 0; bnd < s->num_rematrixing_bands; bnd++) | |
1107 | s->rematrixing_flags[bnd] = get_bits1(gbc); | |
1108 | } else if (!blk) { | |
1109 | av_log(s->avctx, AV_LOG_WARNING, "Warning: " | |
1110 | "new rematrixing strategy not present in block 0\n"); | |
1111 | s->num_rematrixing_bands = 0; | |
1112 | } | |
1113 | } | |
1114 | ||
1115 | /* exponent strategies for each channel */ | |
1116 | for (ch = !cpl_in_use; ch <= s->channels; ch++) { | |
1117 | if (!s->eac3) | |
1118 | s->exp_strategy[blk][ch] = get_bits(gbc, 2 - (ch == s->lfe_ch)); | |
1119 | if (s->exp_strategy[blk][ch] != EXP_REUSE) | |
1120 | bit_alloc_stages[ch] = 3; | |
1121 | } | |
1122 | ||
1123 | /* channel bandwidth */ | |
1124 | for (ch = 1; ch <= fbw_channels; ch++) { | |
1125 | s->start_freq[ch] = 0; | |
1126 | if (s->exp_strategy[blk][ch] != EXP_REUSE) { | |
1127 | int group_size; | |
1128 | int prev = s->end_freq[ch]; | |
1129 | if (s->channel_in_cpl[ch]) | |
1130 | s->end_freq[ch] = s->start_freq[CPL_CH]; | |
1131 | else if (s->channel_uses_spx[ch]) | |
1132 | s->end_freq[ch] = s->spx_src_start_freq; | |
1133 | else { | |
1134 | int bandwidth_code = get_bits(gbc, 6); | |
1135 | if (bandwidth_code > 60) { | |
1136 | av_log(s->avctx, AV_LOG_ERROR, "bandwidth code = %d > 60\n", bandwidth_code); | |
1137 | return AVERROR_INVALIDDATA; | |
1138 | } | |
1139 | s->end_freq[ch] = bandwidth_code * 3 + 73; | |
1140 | } | |
1141 | group_size = 3 << (s->exp_strategy[blk][ch] - 1); | |
1142 | s->num_exp_groups[ch] = (s->end_freq[ch] + group_size-4) / group_size; | |
1143 | if (blk > 0 && s->end_freq[ch] != prev) | |
1144 | memset(bit_alloc_stages, 3, AC3_MAX_CHANNELS); | |
1145 | } | |
1146 | } | |
1147 | if (cpl_in_use && s->exp_strategy[blk][CPL_CH] != EXP_REUSE) { | |
1148 | s->num_exp_groups[CPL_CH] = (s->end_freq[CPL_CH] - s->start_freq[CPL_CH]) / | |
1149 | (3 << (s->exp_strategy[blk][CPL_CH] - 1)); | |
1150 | } | |
1151 | ||
1152 | /* decode exponents for each channel */ | |
1153 | for (ch = !cpl_in_use; ch <= s->channels; ch++) { | |
1154 | if (s->exp_strategy[blk][ch] != EXP_REUSE) { | |
1155 | s->dexps[ch][0] = get_bits(gbc, 4) << !ch; | |
1156 | if (decode_exponents(gbc, s->exp_strategy[blk][ch], | |
1157 | s->num_exp_groups[ch], s->dexps[ch][0], | |
1158 | &s->dexps[ch][s->start_freq[ch]+!!ch])) { | |
1159 | av_log(s->avctx, AV_LOG_ERROR, "exponent out-of-range\n"); | |
1160 | return AVERROR_INVALIDDATA; | |
1161 | } | |
1162 | if (ch != CPL_CH && ch != s->lfe_ch) | |
1163 | skip_bits(gbc, 2); /* skip gainrng */ | |
1164 | } | |
1165 | } | |
1166 | ||
1167 | /* bit allocation information */ | |
1168 | if (s->bit_allocation_syntax) { | |
1169 | if (get_bits1(gbc)) { | |
1170 | s->bit_alloc_params.slow_decay = ff_ac3_slow_decay_tab[get_bits(gbc, 2)] >> s->bit_alloc_params.sr_shift; | |
1171 | s->bit_alloc_params.fast_decay = ff_ac3_fast_decay_tab[get_bits(gbc, 2)] >> s->bit_alloc_params.sr_shift; | |
1172 | s->bit_alloc_params.slow_gain = ff_ac3_slow_gain_tab[get_bits(gbc, 2)]; | |
1173 | s->bit_alloc_params.db_per_bit = ff_ac3_db_per_bit_tab[get_bits(gbc, 2)]; | |
1174 | s->bit_alloc_params.floor = ff_ac3_floor_tab[get_bits(gbc, 3)]; | |
1175 | for (ch = !cpl_in_use; ch <= s->channels; ch++) | |
1176 | bit_alloc_stages[ch] = FFMAX(bit_alloc_stages[ch], 2); | |
1177 | } else if (!blk) { | |
1178 | av_log(s->avctx, AV_LOG_ERROR, "new bit allocation info must " | |
1179 | "be present in block 0\n"); | |
1180 | return AVERROR_INVALIDDATA; | |
1181 | } | |
1182 | } | |
1183 | ||
1184 | /* signal-to-noise ratio offsets and fast gains (signal-to-mask ratios) */ | |
1185 | if (!s->eac3 || !blk) { | |
1186 | if (s->snr_offset_strategy && get_bits1(gbc)) { | |
1187 | int snr = 0; | |
1188 | int csnr; | |
1189 | csnr = (get_bits(gbc, 6) - 15) << 4; | |
1190 | for (i = ch = !cpl_in_use; ch <= s->channels; ch++) { | |
1191 | /* snr offset */ | |
1192 | if (ch == i || s->snr_offset_strategy == 2) | |
1193 | snr = (csnr + get_bits(gbc, 4)) << 2; | |
1194 | /* run at least last bit allocation stage if snr offset changes */ | |
1195 | if (blk && s->snr_offset[ch] != snr) { | |
1196 | bit_alloc_stages[ch] = FFMAX(bit_alloc_stages[ch], 1); | |
1197 | } | |
1198 | s->snr_offset[ch] = snr; | |
1199 | ||
1200 | /* fast gain (normal AC-3 only) */ | |
1201 | if (!s->eac3) { | |
1202 | int prev = s->fast_gain[ch]; | |
1203 | s->fast_gain[ch] = ff_ac3_fast_gain_tab[get_bits(gbc, 3)]; | |
1204 | /* run last 2 bit allocation stages if fast gain changes */ | |
1205 | if (blk && prev != s->fast_gain[ch]) | |
1206 | bit_alloc_stages[ch] = FFMAX(bit_alloc_stages[ch], 2); | |
1207 | } | |
1208 | } | |
1209 | } else if (!s->eac3 && !blk) { | |
1210 | av_log(s->avctx, AV_LOG_ERROR, "new snr offsets must be present in block 0\n"); | |
1211 | return AVERROR_INVALIDDATA; | |
1212 | } | |
1213 | } | |
1214 | ||
1215 | /* fast gain (E-AC-3 only) */ | |
1216 | if (s->fast_gain_syntax && get_bits1(gbc)) { | |
1217 | for (ch = !cpl_in_use; ch <= s->channels; ch++) { | |
1218 | int prev = s->fast_gain[ch]; | |
1219 | s->fast_gain[ch] = ff_ac3_fast_gain_tab[get_bits(gbc, 3)]; | |
1220 | /* run last 2 bit allocation stages if fast gain changes */ | |
1221 | if (blk && prev != s->fast_gain[ch]) | |
1222 | bit_alloc_stages[ch] = FFMAX(bit_alloc_stages[ch], 2); | |
1223 | } | |
1224 | } else if (s->eac3 && !blk) { | |
1225 | for (ch = !cpl_in_use; ch <= s->channels; ch++) | |
1226 | s->fast_gain[ch] = ff_ac3_fast_gain_tab[4]; | |
1227 | } | |
1228 | ||
1229 | /* E-AC-3 to AC-3 converter SNR offset */ | |
1230 | if (s->frame_type == EAC3_FRAME_TYPE_INDEPENDENT && get_bits1(gbc)) { | |
1231 | skip_bits(gbc, 10); // skip converter snr offset | |
1232 | } | |
1233 | ||
1234 | /* coupling leak information */ | |
1235 | if (cpl_in_use) { | |
1236 | if (s->first_cpl_leak || get_bits1(gbc)) { | |
1237 | int fl = get_bits(gbc, 3); | |
1238 | int sl = get_bits(gbc, 3); | |
1239 | /* run last 2 bit allocation stages for coupling channel if | |
1240 | coupling leak changes */ | |
1241 | if (blk && (fl != s->bit_alloc_params.cpl_fast_leak || | |
1242 | sl != s->bit_alloc_params.cpl_slow_leak)) { | |
1243 | bit_alloc_stages[CPL_CH] = FFMAX(bit_alloc_stages[CPL_CH], 2); | |
1244 | } | |
1245 | s->bit_alloc_params.cpl_fast_leak = fl; | |
1246 | s->bit_alloc_params.cpl_slow_leak = sl; | |
1247 | } else if (!s->eac3 && !blk) { | |
1248 | av_log(s->avctx, AV_LOG_ERROR, "new coupling leak info must " | |
1249 | "be present in block 0\n"); | |
1250 | return AVERROR_INVALIDDATA; | |
1251 | } | |
1252 | s->first_cpl_leak = 0; | |
1253 | } | |
1254 | ||
1255 | /* delta bit allocation information */ | |
1256 | if (s->dba_syntax && get_bits1(gbc)) { | |
1257 | /* delta bit allocation exists (strategy) */ | |
1258 | for (ch = !cpl_in_use; ch <= fbw_channels; ch++) { | |
1259 | s->dba_mode[ch] = get_bits(gbc, 2); | |
1260 | if (s->dba_mode[ch] == DBA_RESERVED) { | |
1261 | av_log(s->avctx, AV_LOG_ERROR, "delta bit allocation strategy reserved\n"); | |
1262 | return AVERROR_INVALIDDATA; | |
1263 | } | |
1264 | bit_alloc_stages[ch] = FFMAX(bit_alloc_stages[ch], 2); | |
1265 | } | |
1266 | /* channel delta offset, len and bit allocation */ | |
1267 | for (ch = !cpl_in_use; ch <= fbw_channels; ch++) { | |
1268 | if (s->dba_mode[ch] == DBA_NEW) { | |
1269 | s->dba_nsegs[ch] = get_bits(gbc, 3) + 1; | |
1270 | for (seg = 0; seg < s->dba_nsegs[ch]; seg++) { | |
1271 | s->dba_offsets[ch][seg] = get_bits(gbc, 5); | |
1272 | s->dba_lengths[ch][seg] = get_bits(gbc, 4); | |
1273 | s->dba_values[ch][seg] = get_bits(gbc, 3); | |
1274 | } | |
1275 | /* run last 2 bit allocation stages if new dba values */ | |
1276 | bit_alloc_stages[ch] = FFMAX(bit_alloc_stages[ch], 2); | |
1277 | } | |
1278 | } | |
1279 | } else if (blk == 0) { | |
1280 | for (ch = 0; ch <= s->channels; ch++) { | |
1281 | s->dba_mode[ch] = DBA_NONE; | |
1282 | } | |
1283 | } | |
1284 | ||
1285 | /* Bit allocation */ | |
1286 | for (ch = !cpl_in_use; ch <= s->channels; ch++) { | |
1287 | if (bit_alloc_stages[ch] > 2) { | |
1288 | /* Exponent mapping into PSD and PSD integration */ | |
1289 | ff_ac3_bit_alloc_calc_psd(s->dexps[ch], | |
1290 | s->start_freq[ch], s->end_freq[ch], | |
1291 | s->psd[ch], s->band_psd[ch]); | |
1292 | } | |
1293 | if (bit_alloc_stages[ch] > 1) { | |
1294 | /* Compute excitation function, Compute masking curve, and | |
1295 | Apply delta bit allocation */ | |
1296 | if (ff_ac3_bit_alloc_calc_mask(&s->bit_alloc_params, s->band_psd[ch], | |
1297 | s->start_freq[ch], s->end_freq[ch], | |
1298 | s->fast_gain[ch], (ch == s->lfe_ch), | |
1299 | s->dba_mode[ch], s->dba_nsegs[ch], | |
1300 | s->dba_offsets[ch], s->dba_lengths[ch], | |
1301 | s->dba_values[ch], s->mask[ch])) { | |
1302 | av_log(s->avctx, AV_LOG_ERROR, "error in bit allocation\n"); | |
1303 | return AVERROR_INVALIDDATA; | |
1304 | } | |
1305 | } | |
1306 | if (bit_alloc_stages[ch] > 0) { | |
1307 | /* Compute bit allocation */ | |
1308 | const uint8_t *bap_tab = s->channel_uses_aht[ch] ? | |
1309 | ff_eac3_hebap_tab : ff_ac3_bap_tab; | |
1310 | s->ac3dsp.bit_alloc_calc_bap(s->mask[ch], s->psd[ch], | |
1311 | s->start_freq[ch], s->end_freq[ch], | |
1312 | s->snr_offset[ch], | |
1313 | s->bit_alloc_params.floor, | |
1314 | bap_tab, s->bap[ch]); | |
1315 | } | |
1316 | } | |
1317 | ||
1318 | /* unused dummy data */ | |
1319 | if (s->skip_syntax && get_bits1(gbc)) { | |
1320 | int skipl = get_bits(gbc, 9); | |
1321 | while (skipl--) | |
1322 | skip_bits(gbc, 8); | |
1323 | } | |
1324 | ||
1325 | /* unpack the transform coefficients | |
1326 | this also uncouples channels if coupling is in use. */ | |
1327 | decode_transform_coeffs(s, blk); | |
1328 | ||
1329 | /* TODO: generate enhanced coupling coordinates and uncouple */ | |
1330 | ||
1331 | /* recover coefficients if rematrixing is in use */ | |
1332 | if (s->channel_mode == AC3_CHMODE_STEREO) | |
1333 | do_rematrixing(s); | |
1334 | ||
1335 | /* apply scaling to coefficients (headroom, dynrng) */ | |
1336 | for (ch = 1; ch <= s->channels; ch++) { | |
1337 | int audio_channel = 0; | |
1338 | INTFLOAT gain; | |
1339 | if (s->channel_mode == AC3_CHMODE_DUALMONO) | |
1340 | audio_channel = 2-ch; | |
1341 | if (s->heavy_compression && s->compression_exists[audio_channel]) | |
1342 | gain = s->heavy_dynamic_range[audio_channel]; | |
1343 | else | |
1344 | gain = s->dynamic_range[audio_channel]; | |
1345 | ||
1346 | #if USE_FIXED | |
1347 | scale_coefs(s->transform_coeffs[ch], s->fixed_coeffs[ch], gain, 256); | |
1348 | #else | |
1349 | if (s->target_level != 0) | |
1350 | gain = gain * s->level_gain[audio_channel]; | |
1351 | gain *= 1.0 / 4194304.0f; | |
1352 | s->fmt_conv.int32_to_float_fmul_scalar(s->transform_coeffs[ch], | |
1353 | s->fixed_coeffs[ch], gain, 256); | |
1354 | #endif | |
1355 | } | |
1356 | ||
1357 | /* apply spectral extension to high frequency bins */ | |
1358 | if (s->spx_in_use && CONFIG_EAC3_DECODER) { | |
1359 | ff_eac3_apply_spectral_extension(s); | |
1360 | } | |
1361 | ||
1362 | /* downmix and MDCT. order depends on whether block switching is used for | |
1363 | any channel in this block. this is because coefficients for the long | |
1364 | and short transforms cannot be mixed. */ | |
1365 | downmix_output = s->channels != s->out_channels && | |
1366 | !((s->output_mode & AC3_OUTPUT_LFEON) && | |
1367 | s->fbw_channels == s->out_channels); | |
1368 | if (different_transforms) { | |
1369 | /* the delay samples have already been downmixed, so we upmix the delay | |
1370 | samples in order to reconstruct all channels before downmixing. */ | |
1371 | if (s->downmixed) { | |
1372 | s->downmixed = 0; | |
1373 | ac3_upmix_delay(s); | |
1374 | } | |
1375 | ||
1376 | do_imdct(s, s->channels); | |
1377 | ||
1378 | if (downmix_output) { | |
1379 | #if USE_FIXED | |
1380 | ac3_downmix_c_fixed16(s->outptr, s->downmix_coeffs, | |
1381 | s->out_channels, s->fbw_channels, 256); | |
1382 | #else | |
1383 | s->ac3dsp.downmix(s->outptr, s->downmix_coeffs, | |
1384 | s->out_channels, s->fbw_channels, 256); | |
1385 | #endif | |
1386 | } | |
1387 | } else { | |
1388 | if (downmix_output) { | |
1389 | s->ac3dsp.AC3_RENAME(downmix)(s->xcfptr + 1, s->downmix_coeffs, | |
1390 | s->out_channels, s->fbw_channels, 256); | |
1391 | } | |
1392 | ||
1393 | if (downmix_output && !s->downmixed) { | |
1394 | s->downmixed = 1; | |
1395 | s->ac3dsp.AC3_RENAME(downmix)(s->dlyptr, s->downmix_coeffs, | |
1396 | s->out_channels, s->fbw_channels, 128); | |
1397 | } | |
1398 | ||
1399 | do_imdct(s, s->out_channels); | |
1400 | } | |
1401 | ||
1402 | return 0; | |
1403 | } | |
1404 | ||
1405 | /** | |
1406 | * Decode a single AC-3 frame. | |
1407 | */ | |
1408 | static int ac3_decode_frame(AVCodecContext * avctx, void *data, | |
1409 | int *got_frame_ptr, AVPacket *avpkt) | |
1410 | { | |
1411 | AVFrame *frame = data; | |
1412 | const uint8_t *buf = avpkt->data; | |
1413 | int buf_size = avpkt->size; | |
1414 | AC3DecodeContext *s = avctx->priv_data; | |
1415 | int blk, ch, err, ret; | |
1416 | const uint8_t *channel_map; | |
1417 | const SHORTFLOAT *output[AC3_MAX_CHANNELS]; | |
1418 | enum AVMatrixEncoding matrix_encoding; | |
1419 | AVDownmixInfo *downmix_info; | |
1420 | ||
1421 | /* copy input buffer to decoder context to avoid reading past the end | |
1422 | of the buffer, which can be caused by a damaged input stream. */ | |
1423 | if (buf_size >= 2 && AV_RB16(buf) == 0x770B) { | |
1424 | // seems to be byte-swapped AC-3 | |
1425 | int cnt = FFMIN(buf_size, AC3_FRAME_BUFFER_SIZE) >> 1; | |
1426 | s->bdsp.bswap16_buf((uint16_t *) s->input_buffer, | |
1427 | (const uint16_t *) buf, cnt); | |
1428 | } else | |
1429 | memcpy(s->input_buffer, buf, FFMIN(buf_size, AC3_FRAME_BUFFER_SIZE)); | |
1430 | buf = s->input_buffer; | |
1431 | /* initialize the GetBitContext with the start of valid AC-3 Frame */ | |
1432 | init_get_bits(&s->gbc, buf, buf_size * 8); | |
1433 | ||
1434 | /* parse the syncinfo */ | |
1435 | err = parse_frame_header(s); | |
1436 | ||
1437 | if (err) { | |
1438 | switch (err) { | |
1439 | case AAC_AC3_PARSE_ERROR_SYNC: | |
1440 | av_log(avctx, AV_LOG_ERROR, "frame sync error\n"); | |
1441 | return AVERROR_INVALIDDATA; | |
1442 | case AAC_AC3_PARSE_ERROR_BSID: | |
1443 | av_log(avctx, AV_LOG_ERROR, "invalid bitstream id\n"); | |
1444 | break; | |
1445 | case AAC_AC3_PARSE_ERROR_SAMPLE_RATE: | |
1446 | av_log(avctx, AV_LOG_ERROR, "invalid sample rate\n"); | |
1447 | break; | |
1448 | case AAC_AC3_PARSE_ERROR_FRAME_SIZE: | |
1449 | av_log(avctx, AV_LOG_ERROR, "invalid frame size\n"); | |
1450 | break; | |
1451 | case AAC_AC3_PARSE_ERROR_FRAME_TYPE: | |
1452 | /* skip frame if CRC is ok. otherwise use error concealment. */ | |
1453 | /* TODO: add support for substreams and dependent frames */ | |
1454 | if (s->frame_type == EAC3_FRAME_TYPE_DEPENDENT || s->substreamid) { | |
1455 | av_log(avctx, AV_LOG_WARNING, "unsupported frame type : " | |
1456 | "skipping frame\n"); | |
1457 | *got_frame_ptr = 0; | |
1458 | return buf_size; | |
1459 | } else { | |
1460 | av_log(avctx, AV_LOG_ERROR, "invalid frame type\n"); | |
1461 | } | |
1462 | break; | |
1463 | case AAC_AC3_PARSE_ERROR_CRC: | |
1464 | case AAC_AC3_PARSE_ERROR_CHANNEL_CFG: | |
1465 | break; | |
1466 | default: // Normal AVERROR do not try to recover. | |
1467 | *got_frame_ptr = 0; | |
1468 | return err; | |
1469 | } | |
1470 | } else { | |
1471 | /* check that reported frame size fits in input buffer */ | |
1472 | if (s->frame_size > buf_size) { | |
1473 | av_log(avctx, AV_LOG_ERROR, "incomplete frame\n"); | |
1474 | err = AAC_AC3_PARSE_ERROR_FRAME_SIZE; | |
1475 | } else if (avctx->err_recognition & (AV_EF_CRCCHECK|AV_EF_CAREFUL)) { | |
1476 | /* check for crc mismatch */ | |
1477 | if (av_crc(av_crc_get_table(AV_CRC_16_ANSI), 0, &buf[2], | |
1478 | s->frame_size - 2)) { | |
1479 | av_log(avctx, AV_LOG_ERROR, "frame CRC mismatch\n"); | |
1480 | if (avctx->err_recognition & AV_EF_EXPLODE) | |
1481 | return AVERROR_INVALIDDATA; | |
1482 | err = AAC_AC3_PARSE_ERROR_CRC; | |
1483 | } | |
1484 | } | |
1485 | } | |
1486 | ||
1487 | /* if frame is ok, set audio parameters */ | |
1488 | if (!err) { | |
1489 | avctx->sample_rate = s->sample_rate; | |
1490 | avctx->bit_rate = s->bit_rate; | |
1491 | } | |
1492 | ||
1493 | /* channel config */ | |
1494 | if (!err || (s->channels && s->out_channels != s->channels)) { | |
1495 | s->out_channels = s->channels; | |
1496 | s->output_mode = s->channel_mode; | |
1497 | if (s->lfe_on) | |
1498 | s->output_mode |= AC3_OUTPUT_LFEON; | |
1499 | if (s->channels > 1 && | |
1500 | avctx->request_channel_layout == AV_CH_LAYOUT_MONO) { | |
1501 | s->out_channels = 1; | |
1502 | s->output_mode = AC3_CHMODE_MONO; | |
1503 | } else if (s->channels > 2 && | |
1504 | avctx->request_channel_layout == AV_CH_LAYOUT_STEREO) { | |
1505 | s->out_channels = 2; | |
1506 | s->output_mode = AC3_CHMODE_STEREO; | |
1507 | } | |
1508 | ||
1509 | s->loro_center_mix_level = gain_levels[s-> center_mix_level]; | |
1510 | s->loro_surround_mix_level = gain_levels[s->surround_mix_level]; | |
1511 | s->ltrt_center_mix_level = LEVEL_MINUS_3DB; | |
1512 | s->ltrt_surround_mix_level = LEVEL_MINUS_3DB; | |
1513 | /* set downmixing coefficients if needed */ | |
1514 | if (s->channels != s->out_channels && !((s->output_mode & AC3_OUTPUT_LFEON) && | |
1515 | s->fbw_channels == s->out_channels)) { | |
1516 | set_downmix_coeffs(s); | |
1517 | } | |
1518 | } else if (!s->channels) { | |
1519 | av_log(avctx, AV_LOG_ERROR, "unable to determine channel mode\n"); | |
1520 | return AVERROR_INVALIDDATA; | |
1521 | } | |
1522 | avctx->channels = s->out_channels; | |
1523 | avctx->channel_layout = avpriv_ac3_channel_layout_tab[s->output_mode & ~AC3_OUTPUT_LFEON]; | |
1524 | if (s->output_mode & AC3_OUTPUT_LFEON) | |
1525 | avctx->channel_layout |= AV_CH_LOW_FREQUENCY; | |
1526 | ||
1527 | /* set audio service type based on bitstream mode for AC-3 */ | |
1528 | avctx->audio_service_type = s->bitstream_mode; | |
1529 | if (s->bitstream_mode == 0x7 && s->channels > 1) | |
1530 | avctx->audio_service_type = AV_AUDIO_SERVICE_TYPE_KARAOKE; | |
1531 | ||
1532 | /* get output buffer */ | |
1533 | frame->nb_samples = s->num_blocks * AC3_BLOCK_SIZE; | |
1534 | if ((ret = ff_get_buffer(avctx, frame, 0)) < 0) | |
1535 | return ret; | |
1536 | ||
1537 | /* decode the audio blocks */ | |
1538 | channel_map = ff_ac3_dec_channel_map[s->output_mode & ~AC3_OUTPUT_LFEON][s->lfe_on]; | |
1539 | for (ch = 0; ch < AC3_MAX_CHANNELS; ch++) { | |
1540 | output[ch] = s->output[ch]; | |
1541 | s->outptr[ch] = s->output[ch]; | |
1542 | } | |
1543 | for (ch = 0; ch < s->channels; ch++) { | |
1544 | if (ch < s->out_channels) | |
1545 | s->outptr[channel_map[ch]] = (SHORTFLOAT *)frame->data[ch]; | |
1546 | } | |
1547 | for (blk = 0; blk < s->num_blocks; blk++) { | |
1548 | if (!err && decode_audio_block(s, blk)) { | |
1549 | av_log(avctx, AV_LOG_ERROR, "error decoding the audio block\n"); | |
1550 | err = 1; | |
1551 | } | |
1552 | if (err) | |
1553 | for (ch = 0; ch < s->out_channels; ch++) | |
1554 | memcpy(((SHORTFLOAT*)frame->data[ch]) + AC3_BLOCK_SIZE*blk, output[ch], AC3_BLOCK_SIZE*sizeof(SHORTFLOAT)); | |
1555 | for (ch = 0; ch < s->out_channels; ch++) | |
1556 | output[ch] = s->outptr[channel_map[ch]]; | |
1557 | for (ch = 0; ch < s->out_channels; ch++) { | |
1558 | if (!ch || channel_map[ch]) | |
1559 | s->outptr[channel_map[ch]] += AC3_BLOCK_SIZE; | |
1560 | } | |
1561 | } | |
1562 | ||
1563 | av_frame_set_decode_error_flags(frame, err ? FF_DECODE_ERROR_INVALID_BITSTREAM : 0); | |
1564 | ||
1565 | /* keep last block for error concealment in next frame */ | |
1566 | for (ch = 0; ch < s->out_channels; ch++) | |
1567 | memcpy(s->output[ch], output[ch], AC3_BLOCK_SIZE*sizeof(SHORTFLOAT)); | |
1568 | ||
1569 | /* | |
1570 | * AVMatrixEncoding | |
1571 | * | |
1572 | * Check whether the input layout is compatible, and make sure we're not | |
1573 | * downmixing (else the matrix encoding is no longer applicable). | |
1574 | */ | |
1575 | matrix_encoding = AV_MATRIX_ENCODING_NONE; | |
1576 | if (s->channel_mode == AC3_CHMODE_STEREO && | |
1577 | s->channel_mode == (s->output_mode & ~AC3_OUTPUT_LFEON)) { | |
1578 | if (s->dolby_surround_mode == AC3_DSURMOD_ON) | |
1579 | matrix_encoding = AV_MATRIX_ENCODING_DOLBY; | |
1580 | else if (s->dolby_headphone_mode == AC3_DHEADPHONMOD_ON) | |
1581 | matrix_encoding = AV_MATRIX_ENCODING_DOLBYHEADPHONE; | |
1582 | } else if (s->channel_mode >= AC3_CHMODE_2F2R && | |
1583 | s->channel_mode == (s->output_mode & ~AC3_OUTPUT_LFEON)) { | |
1584 | switch (s->dolby_surround_ex_mode) { | |
1585 | case AC3_DSUREXMOD_ON: // EX or PLIIx | |
1586 | matrix_encoding = AV_MATRIX_ENCODING_DOLBYEX; | |
1587 | break; | |
1588 | case AC3_DSUREXMOD_PLIIZ: | |
1589 | matrix_encoding = AV_MATRIX_ENCODING_DPLIIZ; | |
1590 | break; | |
1591 | default: // not indicated or off | |
1592 | break; | |
1593 | } | |
1594 | } | |
1595 | if ((ret = ff_side_data_update_matrix_encoding(frame, matrix_encoding)) < 0) | |
1596 | return ret; | |
1597 | ||
1598 | /* AVDownmixInfo */ | |
1599 | if ((downmix_info = av_downmix_info_update_side_data(frame))) { | |
1600 | switch (s->preferred_downmix) { | |
1601 | case AC3_DMIXMOD_LTRT: | |
1602 | downmix_info->preferred_downmix_type = AV_DOWNMIX_TYPE_LTRT; | |
1603 | break; | |
1604 | case AC3_DMIXMOD_LORO: | |
1605 | downmix_info->preferred_downmix_type = AV_DOWNMIX_TYPE_LORO; | |
1606 | break; | |
1607 | case AC3_DMIXMOD_DPLII: | |
1608 | downmix_info->preferred_downmix_type = AV_DOWNMIX_TYPE_DPLII; | |
1609 | break; | |
1610 | default: | |
1611 | downmix_info->preferred_downmix_type = AV_DOWNMIX_TYPE_UNKNOWN; | |
1612 | break; | |
1613 | } | |
1614 | downmix_info->center_mix_level = gain_levels[s-> center_mix_level]; | |
1615 | downmix_info->center_mix_level_ltrt = gain_levels[s-> center_mix_level_ltrt]; | |
1616 | downmix_info->surround_mix_level = gain_levels[s-> surround_mix_level]; | |
1617 | downmix_info->surround_mix_level_ltrt = gain_levels[s->surround_mix_level_ltrt]; | |
1618 | if (s->lfe_mix_level_exists) | |
1619 | downmix_info->lfe_mix_level = gain_levels_lfe[s->lfe_mix_level]; | |
1620 | else | |
1621 | downmix_info->lfe_mix_level = 0.0; // -inf dB | |
1622 | } else | |
1623 | return AVERROR(ENOMEM); | |
1624 | ||
1625 | *got_frame_ptr = 1; | |
1626 | ||
1627 | return FFMIN(buf_size, s->frame_size); | |
1628 | } | |
1629 | ||
1630 | /** | |
1631 | * Uninitialize the AC-3 decoder. | |
1632 | */ | |
1633 | static av_cold int ac3_decode_end(AVCodecContext *avctx) | |
1634 | { | |
1635 | AC3DecodeContext *s = avctx->priv_data; | |
1636 | ff_mdct_end(&s->imdct_512); | |
1637 | ff_mdct_end(&s->imdct_256); | |
2ba45a60 | 1638 | av_freep(&s->fdsp); |
2ba45a60 DM |
1639 | |
1640 | return 0; | |
1641 | } | |
1642 | ||
1643 | #define OFFSET(x) offsetof(AC3DecodeContext, x) | |
1644 | #define PAR (AV_OPT_FLAG_DECODING_PARAM | AV_OPT_FLAG_AUDIO_PARAM) |