FFmpeg: libavcodec/ac3enc.c Source File

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ac3enc.c

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1 /*

2 * The simplest AC-3 encoder

6 *

7 * This file is part of FFmpeg.

8 *

9 * FFmpeg is free software; you can redistribute it and/or

10 * modify it under the terms of the GNU Lesser General Public

11 * License as published by the Free Software Foundation; either

12 * version 2.1 of the License, or (at your option) any later version.

13 *

14 * FFmpeg is distributed in the hope that it will be useful,

15 * but WITHOUT ANY WARRANTY; without even the implied warranty of

16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU

17 * Lesser General Public License for more details.

18 *

19 * You should have received a copy of the GNU Lesser General Public

20 * License along with FFmpeg; if not, write to the Free Software

21 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA

22 */

24 /**

25 * @file

26 * The simplest AC-3 encoder.

27 */

29 #include <stdint.h>

31 #include "libavutil/attributes.h"

32 #include "libavutil/avassert.h"

33 #include "libavutil/avstring.h"

34 #include "libavutil/channel_layout.h"

35 #include "libavutil/crc.h"

36 #include "libavutil/internal.h"

37 #include "libavutil/opt.h"

38 #include "avcodec.h"

39 #include "me_cmp.h"

40 #include "put_bits.h"

41 #include "audiodsp.h"

42 #include "ac3dsp.h"

43 #include "ac3.h"

44 #include "fft.h"

45 #include "ac3enc.h"

46 #include "eac3enc.h"

48 typedef struct AC3Mant {

49 int16_t *qmant1_ptr, *qmant2_ptr, *qmant4_ptr; ///< mantissa pointers for bap=1,2,4

50 int mant1_cnt, mant2_cnt, mant4_cnt; ///< mantissa counts for bap=1,2,4

51 } AC3Mant;

53 #define CMIXLEV_NUM_OPTIONS 3

54 static const float cmixlev_options[CMIXLEV_NUM_OPTIONS] = {

55 LEVEL_MINUS_3DB, LEVEL_MINUS_4POINT5DB, LEVEL_MINUS_6DB

56 };

58 #define SURMIXLEV_NUM_OPTIONS 3

59 static const float surmixlev_options[SURMIXLEV_NUM_OPTIONS] = {

60 LEVEL_MINUS_3DB, LEVEL_MINUS_6DB, LEVEL_ZERO

61 };

63 #define EXTMIXLEV_NUM_OPTIONS 8

64 static const float extmixlev_options[EXTMIXLEV_NUM_OPTIONS] = {

65 LEVEL_PLUS_3DB, LEVEL_PLUS_1POINT5DB, LEVEL_ONE, LEVEL_MINUS_4POINT5DB,

66 LEVEL_MINUS_3DB, LEVEL_MINUS_4POINT5DB, LEVEL_MINUS_6DB, LEVEL_ZERO

67 };

70 /**

71 * LUT for number of exponent groups.

72 * exponent_group_tab[coupling][exponent strategy-1][number of coefficients]

73 */

74 static uint8_t exponent_group_tab[2][3][256];

77 /**

78 * List of supported channel layouts.

79 */

80 const uint64_t ff_ac3_channel_layouts[19] = {

81 AV_CH_LAYOUT_MONO,

82 AV_CH_LAYOUT_STEREO,

83 AV_CH_LAYOUT_2_1,

84 AV_CH_LAYOUT_SURROUND,

85 AV_CH_LAYOUT_2_2,

86 AV_CH_LAYOUT_QUAD,

87 AV_CH_LAYOUT_4POINT0,

88 AV_CH_LAYOUT_5POINT0,

89 AV_CH_LAYOUT_5POINT0_BACK,

90 (AV_CH_LAYOUT_MONO | AV_CH_LOW_FREQUENCY),

91 (AV_CH_LAYOUT_STEREO | AV_CH_LOW_FREQUENCY),

92 (AV_CH_LAYOUT_2_1 | AV_CH_LOW_FREQUENCY),

93 (AV_CH_LAYOUT_SURROUND | AV_CH_LOW_FREQUENCY),

94 (AV_CH_LAYOUT_2_2 | AV_CH_LOW_FREQUENCY),

95 (AV_CH_LAYOUT_QUAD | AV_CH_LOW_FREQUENCY),

96 (AV_CH_LAYOUT_4POINT0 | AV_CH_LOW_FREQUENCY),

97 AV_CH_LAYOUT_5POINT1,

98 AV_CH_LAYOUT_5POINT1_BACK,

99 0

100 };

101

102

103 /**

104 * LUT to select the bandwidth code based on the bit rate, sample rate, and

105 * number of full-bandwidth channels.

106 * bandwidth_tab[fbw_channels-1][sample rate code][bit rate code]

107 */

108 static const uint8_t ac3_bandwidth_tab[5][3][19] = {

109 // 32 40 48 56 64 80 96 112 128 160 192 224 256 320 384 448 512 576 640

110

111 { { 0, 0, 0, 12, 16, 32, 48, 48, 48, 48, 48, 48, 48, 48, 48, 48, 48, 48, 48 },

112 { 0, 0, 0, 16, 20, 36, 56, 56, 56, 56, 56, 56, 56, 56, 56, 56, 56, 56, 56 },

113 { 0, 0, 0, 32, 40, 60, 60, 60, 60, 60, 60, 60, 60, 60, 60, 60, 60, 60, 60 } },

114

115 { { 0, 0, 0, 0, 0, 0, 0, 20, 24, 32, 48, 48, 48, 48, 48, 48, 48, 48, 48 },

116 { 0, 0, 0, 0, 0, 0, 4, 24, 28, 36, 56, 56, 56, 56, 56, 56, 56, 56, 56 },

117 { 0, 0, 0, 0, 0, 0, 20, 44, 52, 60, 60, 60, 60, 60, 60, 60, 60, 60, 60 } },

118

119 { { 0, 0, 0, 0, 0, 0, 0, 0, 0, 16, 24, 32, 40, 48, 48, 48, 48, 48, 48 },

120 { 0, 0, 0, 0, 0, 0, 0, 0, 4, 20, 28, 36, 44, 56, 56, 56, 56, 56, 56 },

121 { 0, 0, 0, 0, 0, 0, 0, 0, 20, 40, 48, 60, 60, 60, 60, 60, 60, 60, 60 } },

122

123 { { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 12, 24, 32, 48, 48, 48, 48, 48, 48 },

124 { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 16, 28, 36, 56, 56, 56, 56, 56, 56 },

125 { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 32, 48, 60, 60, 60, 60, 60, 60, 60 } },

126

127 { { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 8, 20, 32, 40, 48, 48, 48, 48 },

128 { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 12, 24, 36, 44, 56, 56, 56, 56 },

129 { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 28, 44, 60, 60, 60, 60, 60, 60 } }

130 };

131

132

133 /**

134 * LUT to select the coupling start band based on the bit rate, sample rate, and

135 * number of full-bandwidth channels. -1 = coupling off

136 * ac3_coupling_start_tab[channel_mode-2][sample rate code][bit rate code]

137 *

138 * TODO: more testing for optimal parameters.

139 * multi-channel tests at 44.1kHz and 32kHz.

140 */

141 static const int8_t ac3_coupling_start_tab[6][3][19] = {

142 // 32 40 48 56 64 80 96 112 128 160 192 224 256 320 384 448 512 576 640

143

144 // 2/0

145 { { 0, 0, 0, 0, 0, 0, 0, 1, 1, 7, 8, 11, 12, -1, -1, -1, -1, -1, -1 },

146 { 0, 0, 0, 0, 0, 0, 1, 3, 5, 7, 10, 12, 13, -1, -1, -1, -1, -1, -1 },

147 { 0, 0, 0, 0, 1, 2, 2, 9, 13, 15, -1, -1, -1, -1, -1, -1, -1, -1, -1 } },

148

149 // 3/0

150 { { 0, 0, 0, 0, 0, 0, 0, 0, 2, 2, 6, 9, 11, 12, 13, -1, -1, -1, -1 },

151 { 0, 0, 0, 0, 0, 0, 0, 0, 2, 2, 6, 9, 11, 12, 13, -1, -1, -1, -1 },

152 { -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1 } },

153

154 // 2/1 - untested

155 { { 0, 0, 0, 0, 0, 0, 0, 0, 2, 2, 6, 9, 11, 12, 13, -1, -1, -1, -1 },

156 { 0, 0, 0, 0, 0, 0, 0, 0, 2, 2, 6, 9, 11, 12, 13, -1, -1, -1, -1 },

157 { -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1 } },

158

159 // 3/1

160 { { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 3, 2, 10, 11, 11, 12, 12, 14, -1 },

161 { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 3, 2, 10, 11, 11, 12, 12, 14, -1 },

162 { -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1 } },

163

164 // 2/2 - untested

165 { { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 3, 2, 10, 11, 11, 12, 12, 14, -1 },

166 { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 3, 2, 10, 11, 11, 12, 12, 14, -1 },

167 { -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1 } },

168

169 // 3/2

170 { { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 6, 8, 11, 12, 12, -1, -1 },

171 { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 6, 8, 11, 12, 12, -1, -1 },

172 { -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1 } },

173 };

174

175

176 /**

177 * Adjust the frame size to make the average bit rate match the target bit rate.

178 * This is only needed for 11025, 22050, and 44100 sample rates or any E-AC-3.

179 *

180 * @param s AC-3 encoder private context

181 */

182 void ff_ac3_adjust_frame_size(AC3EncodeContext *s)

183 {

184 while (s->bits_written >= s->bit_rate && s->samples_written >= s->sample_rate) {

185 s->bits_written -= s->bit_rate;

186 s->samples_written -= s->sample_rate;

187 }

188 s->frame_size = s->frame_size_min +

189 2 * (s->bits_written * s->sample_rate < s->samples_written * s->bit_rate);

190 s->bits_written += s->frame_size * 8;

191 s->samples_written += AC3_BLOCK_SIZE * s->num_blocks;

192 }

193

194

195 /**

196 * Set the initial coupling strategy parameters prior to coupling analysis.

197 *

198 * @param s AC-3 encoder private context

199 */

200 void ff_ac3_compute_coupling_strategy(AC3EncodeContext *s)

201 {

202 int blk, ch;

203 int got_cpl_snr;

204 int num_cpl_blocks;

205

206 /* set coupling use flags for each block/channel */

207 /* TODO: turn coupling on/off and adjust start band based on bit usage */

208 for (blk = 0; blk < s->num_blocks; blk++) {

209 AC3Block *block = &s->blocks[blk];

210 for (ch = 1; ch <= s->fbw_channels; ch++)

211 block->channel_in_cpl[ch] = s->cpl_on;

212 }

213

214 /* enable coupling for each block if at least 2 channels have coupling

215 enabled for that block */

216 got_cpl_snr = 0;

217 num_cpl_blocks = 0;

218 for (blk = 0; blk < s->num_blocks; blk++) {

219 AC3Block *block = &s->blocks[blk];

220 block->num_cpl_channels = 0;

221 for (ch = 1; ch <= s->fbw_channels; ch++)

222 block->num_cpl_channels += block->channel_in_cpl[ch];

223 block->cpl_in_use = block->num_cpl_channels > 1;

224 num_cpl_blocks += block->cpl_in_use;

225 if (!block->cpl_in_use) {

226 block->num_cpl_channels = 0;

227 for (ch = 1; ch <= s->fbw_channels; ch++)

228 block->channel_in_cpl[ch] = 0;

229 }

230

231 block->new_cpl_strategy = !blk;

232 if (blk) {

233 for (ch = 1; ch <= s->fbw_channels; ch++) {

234 if (block->channel_in_cpl[ch] != s->blocks[blk-1].channel_in_cpl[ch]) {

235 block->new_cpl_strategy = 1;

236 break;

237 }

238 }

239 }

240 block->new_cpl_leak = block->new_cpl_strategy;

241

242 if (!blk || (block->cpl_in_use && !got_cpl_snr)) {

243 block->new_snr_offsets = 1;

244 if (block->cpl_in_use)

245 got_cpl_snr = 1;

246 } else {

247 block->new_snr_offsets = 0;

248 }

249 }

250 if (!num_cpl_blocks)

251 s->cpl_on = 0;

252

253 /* set bandwidth for each channel */

254 for (blk = 0; blk < s->num_blocks; blk++) {

255 AC3Block *block = &s->blocks[blk];

256 for (ch = 1; ch <= s->fbw_channels; ch++) {

257 if (block->channel_in_cpl[ch])

258 block->end_freq[ch] = s->start_freq[CPL_CH];

259 else

260 block->end_freq[ch] = s->bandwidth_code * 3 + 73;

261 }

262 }

263 }

264

265

266 /**

267 * Apply stereo rematrixing to coefficients based on rematrixing flags.

268 *

269 * @param s AC-3 encoder private context

270 */

271 void ff_ac3_apply_rematrixing(AC3EncodeContext *s)

272 {

273 int nb_coefs;

274 int blk, bnd, i;

275 int start, end;

276 uint8_t *flags = NULL;

277

278 if (!s->rematrixing_enabled)

279 return;

280

281 for (blk = 0; blk < s->num_blocks; blk++) {

282 AC3Block *block = &s->blocks[blk];

283 if (block->new_rematrixing_strategy)

284 flags = block->rematrixing_flags;

285 nb_coefs = FFMIN(block->end_freq[1], block->end_freq[2]);

286 for (bnd = 0; bnd < block->num_rematrixing_bands; bnd++) {

287 if (flags[bnd]) {

288 start = ff_ac3_rematrix_band_tab[bnd];

289 end = FFMIN(nb_coefs, ff_ac3_rematrix_band_tab[bnd+1]);

290 for (i = start; i < end; i++) {

291 int32_t lt = block->fixed_coef[1][i];

292 int32_t rt = block->fixed_coef[2][i];

293 block->fixed_coef[1][i] = (lt + rt) >> 1;

294 block->fixed_coef[2][i] = (lt - rt) >> 1;

295 }

296 }

297 }

298 }

299 }

300

301

302 /*

303 * Initialize exponent tables.

304 */

305 static av_cold void exponent_init(AC3EncodeContext *s)

306 {

307 int expstr, i, grpsize;

308

309 for (expstr = EXP_D15-1; expstr <= EXP_D45-1; expstr++) {

310 grpsize = 3 << expstr;

311 for (i = 12; i < 256; i++) {

312 exponent_group_tab[0][expstr][i] = (i + grpsize - 4) / grpsize;

313 exponent_group_tab[1][expstr][i] = (i ) / grpsize;

314 }

315 }

316 /* LFE */

317 exponent_group_tab[0][0][7] = 2;

318

319 if (CONFIG_EAC3_ENCODER && s->eac3)

320 ff_eac3_exponent_init();

321 }

322

323

324 /*

325 * Extract exponents from the MDCT coefficients.

326 */

327 static void extract_exponents(AC3EncodeContext *s)

328 {

329 int ch = !s->cpl_on;

330 int chan_size = AC3_MAX_COEFS * s->num_blocks * (s->channels - ch + 1);

331 AC3Block *block = &s->blocks[0];

332

333 s->ac3dsp.extract_exponents(block->exp[ch], block->fixed_coef[ch], chan_size);

334 }

335

336

337 /**

338 * Exponent Difference Threshold.

339 * New exponents are sent if their SAD exceed this number.

340 */

341 #define EXP_DIFF_THRESHOLD 500

342

343 /**

344 * Table used to select exponent strategy based on exponent reuse block interval.

345 */

346 static const uint8_t exp_strategy_reuse_tab[4][6] = {

347 { EXP_D15, EXP_D15, EXP_D15, EXP_D15, EXP_D15, EXP_D15 },

348 { EXP_D15, EXP_D15, EXP_D15, EXP_D15, EXP_D15, EXP_D15 },

349 { EXP_D25, EXP_D25, EXP_D15, EXP_D15, EXP_D15, EXP_D15 },

350 { EXP_D45, EXP_D25, EXP_D25, EXP_D15, EXP_D15, EXP_D15 }

351 };

352

353 /*

354 * Calculate exponent strategies for all channels.

355 * Array arrangement is reversed to simplify the per-channel calculation.

356 */

357 static void compute_exp_strategy(AC3EncodeContext *s)

358 {

359 int ch, blk, blk1;

360

361 for (ch = !s->cpl_on; ch <= s->fbw_channels; ch++) {

362 uint8_t *exp_strategy = s->exp_strategy[ch];

363 uint8_t *exp = s->blocks[0].exp[ch];

364 int exp_diff;

365

366 /* estimate if the exponent variation & decide if they should be

367 reused in the next frame */

368 exp_strategy[0] = EXP_NEW;

369 exp += AC3_MAX_COEFS;

370 for (blk = 1; blk < s->num_blocks; blk++, exp += AC3_MAX_COEFS) {

371 if (ch == CPL_CH) {

372 if (!s->blocks[blk-1].cpl_in_use) {

373 exp_strategy[blk] = EXP_NEW;

374 continue;

375 } else if (!s->blocks[blk].cpl_in_use) {

376 exp_strategy[blk] = EXP_REUSE;

377 continue;

378 }

379 } else if (s->blocks[blk].channel_in_cpl[ch] != s->blocks[blk-1].channel_in_cpl[ch]) {

380 exp_strategy[blk] = EXP_NEW;

381 continue;

382 }

383 exp_diff = s->mecc.sad[0](NULL, exp, exp - AC3_MAX_COEFS, 16, 16);

384 exp_strategy[blk] = EXP_REUSE;

385 if (ch == CPL_CH && exp_diff > (EXP_DIFF_THRESHOLD * (s->blocks[blk].end_freq[ch] - s->start_freq[ch]) / AC3_MAX_COEFS))

386 exp_strategy[blk] = EXP_NEW;

387 else if (ch > CPL_CH && exp_diff > EXP_DIFF_THRESHOLD)

388 exp_strategy[blk] = EXP_NEW;

389 }

390

391 /* now select the encoding strategy type : if exponents are often

392 recoded, we use a coarse encoding */

393 blk = 0;

394 while (blk < s->num_blocks) {

395 blk1 = blk + 1;

396 while (blk1 < s->num_blocks && exp_strategy[blk1] == EXP_REUSE)

397 blk1++;

398 exp_strategy[blk] = exp_strategy_reuse_tab[s->num_blks_code][blk1-blk-1];

399 blk = blk1;

400 }

401 }

402 if (s->lfe_on) {

403 ch = s->lfe_channel;

404 s->exp_strategy[ch][0] = EXP_D15;

405 for (blk = 1; blk < s->num_blocks; blk++)

406 s->exp_strategy[ch][blk] = EXP_REUSE;

407 }

408

409 /* for E-AC-3, determine frame exponent strategy */

410 if (CONFIG_EAC3_ENCODER && s->eac3)

411 ff_eac3_get_frame_exp_strategy(s);

412 }

413

414

415 /**

416 * Update the exponents so that they are the ones the decoder will decode.

417 *

418 * @param[in,out] exp array of exponents for 1 block in 1 channel

419 * @param nb_exps number of exponents in active bandwidth

420 * @param exp_strategy exponent strategy for the block

421 * @param cpl indicates if the block is in the coupling channel

422 */

423 static void encode_exponents_blk_ch(uint8_t *exp, int nb_exps, int exp_strategy,

424 int cpl)

425 {

426 int nb_groups, i, k;

427

428 nb_groups = exponent_group_tab[cpl][exp_strategy-1][nb_exps] * 3;

429

430 /* for each group, compute the minimum exponent */

431 switch(exp_strategy) {

432 case EXP_D25:

433 for (i = 1, k = 1-cpl; i <= nb_groups; i++) {

434 uint8_t exp_min = exp[k];

435 if (exp[k+1] < exp_min)

436 exp_min = exp[k+1];

437 exp[i-cpl] = exp_min;

438 k += 2;

439 }

440 break;

441 case EXP_D45:

442 for (i = 1, k = 1-cpl; i <= nb_groups; i++) {

443 uint8_t exp_min = exp[k];

444 if (exp[k+1] < exp_min)

445 exp_min = exp[k+1];

446 if (exp[k+2] < exp_min)

447 exp_min = exp[k+2];

448 if (exp[k+3] < exp_min)

449 exp_min = exp[k+3];

450 exp[i-cpl] = exp_min;

451 k += 4;

452 }

453 break;

454 }

455

456 /* constraint for DC exponent */

457 if (!cpl && exp[0] > 15)

458 exp[0] = 15;

459

460 /* decrease the delta between each groups to within 2 so that they can be

461 differentially encoded */

462 for (i = 1; i <= nb_groups; i++)

463 exp[i] = FFMIN(exp[i], exp[i-1] + 2);

464 i--;

465 while (--i >= 0)

466 exp[i] = FFMIN(exp[i], exp[i+1] + 2);

467

468 if (cpl)

469 exp[-1] = exp[0] & ~1;

470

471 /* now we have the exponent values the decoder will see */

472 switch (exp_strategy) {

473 case EXP_D25:

474 for (i = nb_groups, k = (nb_groups * 2)-cpl; i > 0; i--) {

475 uint8_t exp1 = exp[i-cpl];

476 exp[k--] = exp1;

477 exp[k--] = exp1;

478 }

479 break;

480 case EXP_D45:

481 for (i = nb_groups, k = (nb_groups * 4)-cpl; i > 0; i--) {

482 exp[k] = exp[k-1] = exp[k-2] = exp[k-3] = exp[i-cpl];

483 k -= 4;

484 }

485 break;

486 }

487 }

488

489

490 /*

491 * Encode exponents from original extracted form to what the decoder will see.

492 * This copies and groups exponents based on exponent strategy and reduces

493 * deltas between adjacent exponent groups so that they can be differentially

494 * encoded.

495 */

496 static void encode_exponents(AC3EncodeContext *s)

497 {

498 int blk, blk1, ch, cpl;

499 uint8_t *exp, *exp_strategy;

500 int nb_coefs, num_reuse_blocks;

501

502 for (ch = !s->cpl_on; ch <= s->channels; ch++) {

503 exp = s->blocks[0].exp[ch] + s->start_freq[ch];

504 exp_strategy = s->exp_strategy[ch];

505

506 cpl = (ch == CPL_CH);

507 blk = 0;

508 while (blk < s->num_blocks) {

509 AC3Block *block = &s->blocks[blk];

510 if (cpl && !block->cpl_in_use) {

511 exp += AC3_MAX_COEFS;

512 blk++;

513 continue;

514 }

515 nb_coefs = block->end_freq[ch] - s->start_freq[ch];

516 blk1 = blk + 1;

517

518 /* count the number of EXP_REUSE blocks after the current block

519 and set exponent reference block numbers */

520 s->exp_ref_block[ch][blk] = blk;

521 while (blk1 < s->num_blocks && exp_strategy[blk1] == EXP_REUSE) {

522 s->exp_ref_block[ch][blk1] = blk;

523 blk1++;

524 }

525 num_reuse_blocks = blk1 - blk - 1;

526

527 /* for the EXP_REUSE case we select the min of the exponents */

528 s->ac3dsp.ac3_exponent_min(exp-s->start_freq[ch], num_reuse_blocks,

529 AC3_MAX_COEFS);

530

531 encode_exponents_blk_ch(exp, nb_coefs, exp_strategy[blk], cpl);

532

533 exp += AC3_MAX_COEFS * (num_reuse_blocks + 1);

534 blk = blk1;

535 }

536 }

537

538 /* reference block numbers have been changed, so reset ref_bap_set */

539 s->ref_bap_set = 0;

540 }

541

542

543 /*

544 * Count exponent bits based on bandwidth, coupling, and exponent strategies.

545 */

546 static int count_exponent_bits(AC3EncodeContext *s)

547 {

548 int blk, ch;

549 int nb_groups, bit_count;

550

551 bit_count = 0;

552 for (blk = 0; blk < s->num_blocks; blk++) {

553 AC3Block *block = &s->blocks[blk];

554 for (ch = !block->cpl_in_use; ch <= s->channels; ch++) {

555 int exp_strategy = s->exp_strategy[ch][blk];

556 int cpl = (ch == CPL_CH);

557 int nb_coefs = block->end_freq[ch] - s->start_freq[ch];

558

559 if (exp_strategy == EXP_REUSE)

560 continue;

561

562 nb_groups = exponent_group_tab[cpl][exp_strategy-1][nb_coefs];

563 bit_count += 4 + (nb_groups * 7);

564 }

565 }

566

567 return bit_count;

568 }

569

570

571 /**

572 * Group exponents.

573 * 3 delta-encoded exponents are in each 7-bit group. The number of groups

574 * varies depending on exponent strategy and bandwidth.

575 *

576 * @param s AC-3 encoder private context

577 */

578 void ff_ac3_group_exponents(AC3EncodeContext *s)

579 {

580 int blk, ch, i, cpl;

581 int group_size, nb_groups;

582 uint8_t *p;

583 int delta0, delta1, delta2;

584 int exp0, exp1;

585

586 for (blk = 0; blk < s->num_blocks; blk++) {

587 AC3Block *block = &s->blocks[blk];

588 for (ch = !block->cpl_in_use; ch <= s->channels; ch++) {

589 int exp_strategy = s->exp_strategy[ch][blk];

590 if (exp_strategy == EXP_REUSE)

591 continue;

592 cpl = (ch == CPL_CH);

593 group_size = exp_strategy + (exp_strategy == EXP_D45);

594 nb_groups = exponent_group_tab[cpl][exp_strategy-1][block->end_freq[ch]-s->start_freq[ch]];

595 p = block->exp[ch] + s->start_freq[ch] - cpl;

596

597 /* DC exponent */

598 exp1 = *p++;

599 block->grouped_exp[ch][0] = exp1;

600

601 /* remaining exponents are delta encoded */

602 for (i = 1; i <= nb_groups; i++) {

603 /* merge three delta in one code */

604 exp0 = exp1;

605 exp1 = p[0];

606 p += group_size;

607 delta0 = exp1 - exp0 + 2;

608 av_assert2(delta0 >= 0 && delta0 <= 4);

609

610 exp0 = exp1;

611 exp1 = p[0];

612 p += group_size;

613 delta1 = exp1 - exp0 + 2;

614 av_assert2(delta1 >= 0 && delta1 <= 4);

615

616 exp0 = exp1;

617 exp1 = p[0];

618 p += group_size;

619 delta2 = exp1 - exp0 + 2;

620 av_assert2(delta2 >= 0 && delta2 <= 4);

621

622 block->grouped_exp[ch][i] = ((delta0 * 5 + delta1) * 5) + delta2;

623 }

624 }

625 }

626 }

627

628

629 /**

630 * Calculate final exponents from the supplied MDCT coefficients and exponent shift.

631 * Extract exponents from MDCT coefficients, calculate exponent strategies,

632 * and encode final exponents.

633 *

634 * @param s AC-3 encoder private context

635 */

636 void ff_ac3_process_exponents(AC3EncodeContext *s)

637 {

638 extract_exponents(s);

639

640 compute_exp_strategy(s);

641

642 encode_exponents(s);

643

644 emms_c();

645 }

646

647

648 /*

649 * Count frame bits that are based solely on fixed parameters.

650 * This only has to be run once when the encoder is initialized.

651 */

652 static void count_frame_bits_fixed(AC3EncodeContext *s)

653 {

654 static const int frame_bits_inc[8] = { 0, 0, 2, 2, 2, 4, 2, 4 };

655 int blk;

656 int frame_bits;

657

658 /* assumptions:

659 * no dynamic range codes

660 * bit allocation parameters do not change between blocks

661 * no delta bit allocation

662 * no skipped data

663 * no auxiliary data

664 * no E-AC-3 metadata

665 */

666

667 /* header */

668 frame_bits = 16; /* sync info */

669 if (s->eac3) {

670 /* bitstream info header */

671 frame_bits += 35;

672 frame_bits += 1 + 1;

673 if (s->num_blocks != 0x6)

674 frame_bits++;

675 frame_bits++;

676 /* audio frame header */

677 if (s->num_blocks == 6)

678 frame_bits += 2;

679 frame_bits += 10;

680 /* exponent strategy */

681 if (s->use_frame_exp_strategy)

682 frame_bits += 5 * s->fbw_channels;

683 else

684 frame_bits += s->num_blocks * 2 * s->fbw_channels;

685 if (s->lfe_on)

686 frame_bits += s->num_blocks;

687 /* converter exponent strategy */

688 if (s->num_blks_code != 0x3)

689 frame_bits++;

690 else

691 frame_bits += s->fbw_channels * 5;

692 /* snr offsets */

693 frame_bits += 10;

694 /* block start info */

695 if (s->num_blocks != 1)

696 frame_bits++;

697 } else {

698 frame_bits += 49;

699 frame_bits += frame_bits_inc[s->channel_mode];

700 }

701

702 /* audio blocks */

703 for (blk = 0; blk < s->num_blocks; blk++) {

704 if (!s->eac3) {

705 /* block switch flags */

706 frame_bits += s->fbw_channels;

707

708 /* dither flags */

709 frame_bits += s->fbw_channels;

710 }

711

712 /* dynamic range */

713 frame_bits++;

714

715 /* spectral extension */

716 if (s->eac3)

717 frame_bits++;

718

719 if (!s->eac3) {

720 /* exponent strategy */

721 frame_bits += 2 * s->fbw_channels;

722 if (s->lfe_on)

723 frame_bits++;

724

725 /* bit allocation params */

726 frame_bits++;

727 if (!blk)

728 frame_bits += 2 + 2 + 2 + 2 + 3;

729 }

730

731 /* converter snr offset */

732 if (s->eac3)

733 frame_bits++;

734

735 if (!s->eac3) {

736 /* delta bit allocation */

737 frame_bits++;

738

739 /* skipped data */

740 frame_bits++;

741 }

742 }

743

744 /* auxiliary data */

745 frame_bits++;

746

747 /* CRC */

748 frame_bits += 1 + 16;

749

750 s->frame_bits_fixed = frame_bits;

751 }

752

753

754 /*

755 * Initialize bit allocation.

756 * Set default parameter codes and calculate parameter values.

757 */

758 static av_cold void bit_alloc_init(AC3EncodeContext *s)

759 {

760 int ch;

761

762 /* init default parameters */

763 s->slow_decay_code = 2;

764 s->fast_decay_code = 1;

765 s->slow_gain_code = 1;

766 s->db_per_bit_code = s->eac3 ? 2 : 3;

767 s->floor_code = 7;

768 for (ch = 0; ch <= s->channels; ch++)

769 s->fast_gain_code[ch] = 4;

770

771 /* initial snr offset */

772 s->coarse_snr_offset = 40;

773

774 /* compute real values */

775 /* currently none of these values change during encoding, so we can just

776 set them once at initialization */

777 s->bit_alloc.slow_decay = ff_ac3_slow_decay_tab[s->slow_decay_code] >> s->bit_alloc.sr_shift;

778 s->bit_alloc.fast_decay = ff_ac3_fast_decay_tab[s->fast_decay_code] >> s->bit_alloc.sr_shift;

779 s->bit_alloc.slow_gain = ff_ac3_slow_gain_tab[s->slow_gain_code];

780 s->bit_alloc.db_per_bit = ff_ac3_db_per_bit_tab[s->db_per_bit_code];

781 s->bit_alloc.floor = ff_ac3_floor_tab[s->floor_code];

782 s->bit_alloc.cpl_fast_leak = 0;

783 s->bit_alloc.cpl_slow_leak = 0;

784

785 count_frame_bits_fixed(s);

786 }

787

788

789 /*

790 * Count the bits used to encode the frame, minus exponents and mantissas.

791 * Bits based on fixed parameters have already been counted, so now we just

792 * have to add the bits based on parameters that change during encoding.

793 */

794 static void count_frame_bits(AC3EncodeContext *s)

795 {

796 AC3EncOptions *opt = &s->options;

797 int blk, ch;

798 int frame_bits = 0;

799

800 /* header */

801 if (s->eac3) {

802 if (opt->eac3_mixing_metadata) {

803 if (s->channel_mode > AC3_CHMODE_STEREO)

804 frame_bits += 2;

805 if (s->has_center)

806 frame_bits += 6;

807 if (s->has_surround)

808 frame_bits += 6;

809 frame_bits += s->lfe_on;

810 frame_bits += 1 + 1 + 2;

811 if (s->channel_mode < AC3_CHMODE_STEREO)

812 frame_bits++;

813 frame_bits++;

814 }

815 if (opt->eac3_info_metadata) {

816 frame_bits += 3 + 1 + 1;

817 if (s->channel_mode == AC3_CHMODE_STEREO)

818 frame_bits += 2 + 2;

819 if (s->channel_mode >= AC3_CHMODE_2F2R)

820 frame_bits += 2;

821 frame_bits++;

822 if (opt->audio_production_info)

823 frame_bits += 5 + 2 + 1;

824 frame_bits++;

825 }

826 /* coupling */

827 if (s->channel_mode > AC3_CHMODE_MONO) {

828 frame_bits++;

829 for (blk = 1; blk < s->num_blocks; blk++) {

830 AC3Block *block = &s->blocks[blk];

831 frame_bits++;

832 if (block->new_cpl_strategy)

833 frame_bits++;

834 }

835 }

836 /* coupling exponent strategy */

837 if (s->cpl_on) {

838 if (s->use_frame_exp_strategy) {

839 frame_bits += 5 * s->cpl_on;

840 } else {

841 for (blk = 0; blk < s->num_blocks; blk++)

842 frame_bits += 2 * s->blocks[blk].cpl_in_use;

843 }

844 }

845 } else {

846 if (opt->audio_production_info)

847 frame_bits += 7;

848 if (s->bitstream_id == 6) {

849 if (opt->extended_bsi_1)

850 frame_bits += 14;

851 if (opt->extended_bsi_2)

852 frame_bits += 14;

853 }

854 }

855

856 /* audio blocks */

857 for (blk = 0; blk < s->num_blocks; blk++) {

858 AC3Block *block = &s->blocks[blk];

859

860 /* coupling strategy */

861 if (!s->eac3)

862 frame_bits++;

863 if (block->new_cpl_strategy) {

864 if (!s->eac3)

865 frame_bits++;

866 if (block->cpl_in_use) {

867 if (s->eac3)

868 frame_bits++;

869 if (!s->eac3 || s->channel_mode != AC3_CHMODE_STEREO)

870 frame_bits += s->fbw_channels;

871 if (s->channel_mode == AC3_CHMODE_STEREO)

872 frame_bits++;

873 frame_bits += 4 + 4;

874 if (s->eac3)

875 frame_bits++;

876 else

877 frame_bits += s->num_cpl_subbands - 1;

878 }

879 }

880

881 /* coupling coordinates */

882 if (block->cpl_in_use) {

883 for (ch = 1; ch <= s->fbw_channels; ch++) {

884 if (block->channel_in_cpl[ch]) {

885 if (!s->eac3 || block->new_cpl_coords[ch] != 2)

886 frame_bits++;

887 if (block->new_cpl_coords[ch]) {

888 frame_bits += 2;

889 frame_bits += (4 + 4) * s->num_cpl_bands;

890 }

891 }

892 }

893 }

894

895 /* stereo rematrixing */

896 if (s->channel_mode == AC3_CHMODE_STEREO) {

897 if (!s->eac3 || blk > 0)

898 frame_bits++;

899 if (s->blocks[blk].new_rematrixing_strategy)

900 frame_bits += block->num_rematrixing_bands;

901 }

902

903 /* bandwidth codes & gain range */

904 for (ch = 1; ch <= s->fbw_channels; ch++) {

905 if (s->exp_strategy[ch][blk] != EXP_REUSE) {

906 if (!block->channel_in_cpl[ch])

907 frame_bits += 6;

908 frame_bits += 2;

909 }

910 }

911

912 /* coupling exponent strategy */

913 if (!s->eac3 && block->cpl_in_use)

914 frame_bits += 2;

915

916 /* snr offsets and fast gain codes */

917 if (!s->eac3) {

918 frame_bits++;

919 if (block->new_snr_offsets)

920 frame_bits += 6 + (s->channels + block->cpl_in_use) * (4 + 3);

921 }

922

923 /* coupling leak info */

924 if (block->cpl_in_use) {

925 if (!s->eac3 || block->new_cpl_leak != 2)

926 frame_bits++;

927 if (block->new_cpl_leak)

928 frame_bits += 3 + 3;

929 }

930 }

931

932 s->frame_bits = s->frame_bits_fixed + frame_bits;

933 }

934

935

936 /*

937 * Calculate masking curve based on the final exponents.

938 * Also calculate the power spectral densities to use in future calculations.

939 */

940 static void bit_alloc_masking(AC3EncodeContext *s)

941 {

942 int blk, ch;

943

944 for (blk = 0; blk < s->num_blocks; blk++) {

945 AC3Block *block = &s->blocks[blk];

946 for (ch = !block->cpl_in_use; ch <= s->channels; ch++) {

947 /* We only need psd and mask for calculating bap.

948 Since we currently do not calculate bap when exponent

949 strategy is EXP_REUSE we do not need to calculate psd or mask. */

950 if (s->exp_strategy[ch][blk] != EXP_REUSE) {

951 ff_ac3_bit_alloc_calc_psd(block->exp[ch], s->start_freq[ch],

952 block->end_freq[ch], block->psd[ch],

953 block->band_psd[ch]);

954 ff_ac3_bit_alloc_calc_mask(&s->bit_alloc, block->band_psd[ch],

955 s->start_freq[ch], block->end_freq[ch],

956 ff_ac3_fast_gain_tab[s->fast_gain_code[ch]],

957 ch == s->lfe_channel,

958 DBA_NONE, 0, NULL, NULL, NULL,

959 block->mask[ch]);

960 }

961 }

962 }

963 }

964

965

966 /*

967 * Ensure that bap for each block and channel point to the current bap_buffer.

968 * They may have been switched during the bit allocation search.

969 */

970 static void reset_block_bap(AC3EncodeContext *s)

971 {

972 int blk, ch;

973 uint8_t *ref_bap;

974

975 if (s->ref_bap[0][0] == s->bap_buffer && s->ref_bap_set)

976 return;

977

978 ref_bap = s->bap_buffer;

979 for (ch = 0; ch <= s->channels; ch++) {

980 for (blk = 0; blk < s->num_blocks; blk++)

981 s->ref_bap[ch][blk] = ref_bap + AC3_MAX_COEFS * s->exp_ref_block[ch][blk];

982 ref_bap += AC3_MAX_COEFS * s->num_blocks;

983 }

984 s->ref_bap_set = 1;

985 }

986

987

988 /**

989 * Initialize mantissa counts.

990 * These are set so that they are padded to the next whole group size when bits

991 * are counted in compute_mantissa_size.

992 *

993 * @param[in,out] mant_cnt running counts for each bap value for each block

994 */

995 static void count_mantissa_bits_init(uint16_t mant_cnt[AC3_MAX_BLOCKS][16])

996 {

997 int blk;

998

999 for (blk = 0; blk < AC3_MAX_BLOCKS; blk++) {

1000 memset(mant_cnt[blk], 0, sizeof(mant_cnt[blk]));

1001 mant_cnt[blk][1] = mant_cnt[blk][2] = 2;

1002 mant_cnt[blk][4] = 1;

1003 }

1004 }

1005

1006

1007 /**

1008 * Update mantissa bit counts for all blocks in 1 channel in a given bandwidth

1009 * range.

1010 *

1011 * @param s AC-3 encoder private context

1012 * @param ch channel index

1013 * @param[in,out] mant_cnt running counts for each bap value for each block

1014 * @param start starting coefficient bin

1015 * @param end ending coefficient bin

1016 */

1017 static void count_mantissa_bits_update_ch(AC3EncodeContext *s, int ch,

1018 uint16_t mant_cnt[AC3_MAX_BLOCKS][16],

1019 int start, int end)

1020 {

1021 int blk;

1022

1023 for (blk = 0; blk < s->num_blocks; blk++) {

1024 AC3Block *block = &s->blocks[blk];

1025 if (ch == CPL_CH && !block->cpl_in_use)

1026 continue;

1027 s->ac3dsp.update_bap_counts(mant_cnt[blk],

1028 s->ref_bap[ch][blk] + start,

1029 FFMIN(end, block->end_freq[ch]) - start);

1030 }

1031 }

1032

1033

1034 /*

1035 * Count the number of mantissa bits in the frame based on the bap values.

1036 */

1037 static int count_mantissa_bits(AC3EncodeContext *s)

1038 {

1039 int ch, max_end_freq;

1040 LOCAL_ALIGNED_16(uint16_t, mant_cnt, [AC3_MAX_BLOCKS], [16]);

1041

1042 count_mantissa_bits_init(mant_cnt);

1043

1044 max_end_freq = s->bandwidth_code * 3 + 73;

1045 for (ch = !s->cpl_enabled; ch <= s->channels; ch++)

1046 count_mantissa_bits_update_ch(s, ch, mant_cnt, s->start_freq[ch],

1047 max_end_freq);

1048

1049 return s->ac3dsp.compute_mantissa_size(mant_cnt);

1050 }

1051

1052

1053 /**

1054 * Run the bit allocation with a given SNR offset.

1055 * This calculates the bit allocation pointers that will be used to determine

1056 * the quantization of each mantissa.

1057 *

1058 * @param s AC-3 encoder private context

1059 * @param snr_offset SNR offset, 0 to 1023

1060 * @return the number of bits needed for mantissas if the given SNR offset is

1061 * is used.

1062 */

1063 static int bit_alloc(AC3EncodeContext *s, int snr_offset)

1064 {

1065 int blk, ch;

1066

1067 snr_offset = (snr_offset - 240) << 2;

1068

1069 reset_block_bap(s);

1070 for (blk = 0; blk < s->num_blocks; blk++) {

1071 AC3Block *block = &s->blocks[blk];

1072

1073 for (ch = !block->cpl_in_use; ch <= s->channels; ch++) {

1074 /* Currently the only bit allocation parameters which vary across

1075 blocks within a frame are the exponent values. We can take

1076 advantage of that by reusing the bit allocation pointers

1077 whenever we reuse exponents. */

1078 if (s->exp_strategy[ch][blk] != EXP_REUSE) {

1079 s->ac3dsp.bit_alloc_calc_bap(block->mask[ch], block->psd[ch],

1080 s->start_freq[ch], block->end_freq[ch],

1081 snr_offset, s->bit_alloc.floor,

1082 ff_ac3_bap_tab, s->ref_bap[ch][blk]);

1083 }

1084 }

1085 }

1086 return count_mantissa_bits(s);

1087 }

1088

1089

1090 /*

1091 * Constant bitrate bit allocation search.

1092 * Find the largest SNR offset that will allow data to fit in the frame.

1093 */

1094 static int cbr_bit_allocation(AC3EncodeContext *s)

1095 {

1096 int ch;

1097 int bits_left;

1098 int snr_offset, snr_incr;

1099

1100 bits_left = 8 * s->frame_size - (s->frame_bits + s->exponent_bits);

1101 if (bits_left < 0)

1102 return AVERROR(EINVAL);

1103

1104 snr_offset = s->coarse_snr_offset << 4;

1105

1106 /* if previous frame SNR offset was 1023, check if current frame can also

1107 use SNR offset of 1023. if so, skip the search. */

1108 if ((snr_offset | s->fine_snr_offset[1]) == 1023) {

1109 if (bit_alloc(s, 1023) <= bits_left)

1110 return 0;

1111 }

1112

1113 while (snr_offset >= 0 &&

1114 bit_alloc(s, snr_offset) > bits_left) {

1115 snr_offset -= 64;

1116 }

1117 if (snr_offset < 0)

1118 return AVERROR(EINVAL);

1119

1120 FFSWAP(uint8_t *, s->bap_buffer, s->bap1_buffer);

1121 for (snr_incr = 64; snr_incr > 0; snr_incr >>= 2) {

1122 while (snr_offset + snr_incr <= 1023 &&

1123 bit_alloc(s, snr_offset + snr_incr) <= bits_left) {

1124 snr_offset += snr_incr;

1125 FFSWAP(uint8_t *, s->bap_buffer, s->bap1_buffer);

1126 }

1127 }

1128 FFSWAP(uint8_t *, s->bap_buffer, s->bap1_buffer);

1129 reset_block_bap(s);

1130

1131 s->coarse_snr_offset = snr_offset >> 4;

1132 for (ch = !s->cpl_on; ch <= s->channels; ch++)

1133 s->fine_snr_offset[ch] = snr_offset & 0xF;

1134

1135 return 0;

1136 }

1137

1138

1139 /*

1140 * Perform bit allocation search.

1141 * Finds the SNR offset value that maximizes quality and fits in the specified

1142 * frame size. Output is the SNR offset and a set of bit allocation pointers

1143 * used to quantize the mantissas.

1144 */

1145 int ff_ac3_compute_bit_allocation(AC3EncodeContext *s)

1146 {

1147 count_frame_bits(s);

1148

1149 s->exponent_bits = count_exponent_bits(s);

1150

1151 bit_alloc_masking(s);

1152

1153 return cbr_bit_allocation(s);

1154 }

1155

1156

1157 /**

1158 * Symmetric quantization on 'levels' levels.

1159 *

1160 * @param c unquantized coefficient

1161 * @param e exponent

1162 * @param levels number of quantization levels

1163 * @return quantized coefficient

1164 */

1165 static inline int sym_quant(int c, int e, int levels)

1166 {

1167 int v = (((levels * c) >> (24 - e)) + levels) >> 1;

1168 av_assert2(v >= 0 && v < levels);

1169 return v;

1170 }

1171

1172

1173 /**

1174 * Asymmetric quantization on 2^qbits levels.

1175 *

1176 * @param c unquantized coefficient

1177 * @param e exponent

1178 * @param qbits number of quantization bits

1179 * @return quantized coefficient

1180 */

1181 static inline int asym_quant(int c, int e, int qbits)

1182 {

1183 int m;

1184

1185 c = (((c << e) >> (24 - qbits)) + 1) >> 1;

1186 m = (1 << (qbits-1));

1187 if (c >= m)

1188 c = m - 1;

1189 av_assert2(c >= -m);

1190 return c;

1191 }

1192

1193

1194 /**

1195 * Quantize a set of mantissas for a single channel in a single block.

1196 *

1197 * @param s Mantissa count context

1198 * @param fixed_coef unquantized fixed-point coefficients

1199 * @param exp exponents

1200 * @param bap bit allocation pointer indices

1201 * @param[out] qmant quantized coefficients

1202 * @param start_freq starting coefficient bin

1203 * @param end_freq ending coefficient bin

1204 */

1205 static void quantize_mantissas_blk_ch(AC3Mant *s, int32_t *fixed_coef,

1206 uint8_t *exp, uint8_t *bap,

1207 int16_t *qmant, int start_freq,

1208 int end_freq)

1209 {

1210 int i;

1211

1212 for (i = start_freq; i < end_freq; i++) {

1213 int c = fixed_coef[i];

1214 int e = exp[i];

1215 int v = bap[i];

1216 if (v)

1217 switch (v) {

1218 case 1:

1219 v = sym_quant(c, e, 3);

1220 switch (s->mant1_cnt) {

1221 case 0:

1222 s->qmant1_ptr = &qmant[i];

1223 v = 9 * v;

1224 s->mant1_cnt = 1;

1225 break;

1226 case 1:

1227 *s->qmant1_ptr += 3 * v;

1228 s->mant1_cnt = 2;

1229 v = 128;

1230 break;

1231 default:

1232 *s->qmant1_ptr += v;

1233 s->mant1_cnt = 0;

1234 v = 128;

1235 break;

1236 }

1237 break;

1238 case 2:

1239 v = sym_quant(c, e, 5);

1240 switch (s->mant2_cnt) {

1241 case 0:

1242 s->qmant2_ptr = &qmant[i];

1243 v = 25 * v;

1244 s->mant2_cnt = 1;

1245 break;

1246 case 1:

1247 *s->qmant2_ptr += 5 * v;

1248 s->mant2_cnt = 2;

1249 v = 128;

1250 break;

1251 default:

1252 *s->qmant2_ptr += v;

1253 s->mant2_cnt = 0;

1254 v = 128;

1255 break;

1256 }

1257 break;

1258 case 3:

1259 v = sym_quant(c, e, 7);

1260 break;

1261 case 4:

1262 v = sym_quant(c, e, 11);

1263 switch (s->mant4_cnt) {

1264 case 0:

1265 s->qmant4_ptr = &qmant[i];

1266 v = 11 * v;

1267 s->mant4_cnt = 1;

1268 break;

1269 default:

1270 *s->qmant4_ptr += v;

1271 s->mant4_cnt = 0;

1272 v = 128;

1273 break;

1274 }

1275 break;

1276 case 5:

1277 v = sym_quant(c, e, 15);

1278 break;

1279 case 14:

1280 v = asym_quant(c, e, 14);

1281 break;

1282 case 15:

1283 v = asym_quant(c, e, 16);

1284 break;

1285 default:

1286 v = asym_quant(c, e, v - 1);

1287 break;

1288 }

1289 qmant[i] = v;

1290 }

1291 }

1292

1293

1294 /**

1295 * Quantize mantissas using coefficients, exponents, and bit allocation pointers.

1296 *

1297 * @param s AC-3 encoder private context

1298 */

1299 void ff_ac3_quantize_mantissas(AC3EncodeContext *s)

1300 {

1301 int blk, ch, ch0=0, got_cpl;

1302

1303 for (blk = 0; blk < s->num_blocks; blk++) {

1304 AC3Block *block = &s->blocks[blk];

1305 AC3Mant m = { 0 };

1306

1307 got_cpl = !block->cpl_in_use;

1308 for (ch = 1; ch <= s->channels; ch++) {

1309 if (!got_cpl && ch > 1 && block->channel_in_cpl[ch-1]) {

1310 ch0 = ch - 1;

1311 ch = CPL_CH;

1312 got_cpl = 1;

1313 }

1314 quantize_mantissas_blk_ch(&m, block->fixed_coef[ch],

1315 s->blocks[s->exp_ref_block[ch][blk]].exp[ch],

1316 s->ref_bap[ch][blk], block->qmant[ch],

1317 s->start_freq[ch], block->end_freq[ch]);

1318 if (ch == CPL_CH)

1319 ch = ch0;

1320 }

1321 }

1322 }

1323

1324

1325 /*

1326 * Write the AC-3 frame header to the output bitstream.

1327 */

1328 static void ac3_output_frame_header(AC3EncodeContext *s)

1329 {

1330 AC3EncOptions *opt = &s->options;

1331

1332 put_bits(&s->pb, 16, 0x0b77); /* frame header */

1333 put_bits(&s->pb, 16, 0); /* crc1: will be filled later */

1334 put_bits(&s->pb, 2, s->bit_alloc.sr_code);

1335 put_bits(&s->pb, 6, s->frame_size_code + (s->frame_size - s->frame_size_min) / 2);

1336 put_bits(&s->pb, 5, s->bitstream_id);

1337 put_bits(&s->pb, 3, s->bitstream_mode);

1338 put_bits(&s->pb, 3, s->channel_mode);

1339 if ((s->channel_mode & 0x01) && s->channel_mode != AC3_CHMODE_MONO)

1340 put_bits(&s->pb, 2, s->center_mix_level);

1341 if (s->channel_mode & 0x04)

1342 put_bits(&s->pb, 2, s->surround_mix_level);

1343 if (s->channel_mode == AC3_CHMODE_STEREO)

1344 put_bits(&s->pb, 2, opt->dolby_surround_mode);

1345 put_bits(&s->pb, 1, s->lfe_on); /* LFE */

1346 put_bits(&s->pb, 5, -opt->dialogue_level);

1347 put_bits(&s->pb, 1, 0); /* no compression control word */

1348 put_bits(&s->pb, 1, 0); /* no lang code */

1349 put_bits(&s->pb, 1, opt->audio_production_info);

1350 if (opt->audio_production_info) {

1351 put_bits(&s->pb, 5, opt->mixing_level - 80);

1352 put_bits(&s->pb, 2, opt->room_type);

1353 }

1354 put_bits(&s->pb, 1, opt->copyright);

1355 put_bits(&s->pb, 1, opt->original);

1356 if (s->bitstream_id == 6) {

1357 /* alternate bit stream syntax */

1358 put_bits(&s->pb, 1, opt->extended_bsi_1);

1359 if (opt->extended_bsi_1) {

1360 put_bits(&s->pb, 2, opt->preferred_stereo_downmix);

1361 put_bits(&s->pb, 3, s->ltrt_center_mix_level);

1362 put_bits(&s->pb, 3, s->ltrt_surround_mix_level);

1363 put_bits(&s->pb, 3, s->loro_center_mix_level);

1364 put_bits(&s->pb, 3, s->loro_surround_mix_level);

1365 }

1366 put_bits(&s->pb, 1, opt->extended_bsi_2);

1367 if (opt->extended_bsi_2) {

1368 put_bits(&s->pb, 2, opt->dolby_surround_ex_mode);

1369 put_bits(&s->pb, 2, opt->dolby_headphone_mode);

1370 put_bits(&s->pb, 1, opt->ad_converter_type);

1371 put_bits(&s->pb, 9, 0); /* xbsi2 and encinfo : reserved */

1372 }

1373 } else {

1374 put_bits(&s->pb, 1, 0); /* no time code 1 */

1375 put_bits(&s->pb, 1, 0); /* no time code 2 */

1376 }

1377 put_bits(&s->pb, 1, 0); /* no additional bit stream info */

1378 }

1379

1380

1381 /*

1382 * Write one audio block to the output bitstream.

1383 */

1384 static void output_audio_block(AC3EncodeContext *s, int blk)

1385 {

1386 int ch, i, baie, bnd, got_cpl, av_uninit(ch0);

1387 AC3Block *block = &s->blocks[blk];

1388

1389 /* block switching */

1390 if (!s->eac3) {

1391 for (ch = 0; ch < s->fbw_channels; ch++)

1392 put_bits(&s->pb, 1, 0);

1393 }

1394

1395 /* dither flags */

1396 if (!s->eac3) {

1397 for (ch = 0; ch < s->fbw_channels; ch++)

1398 put_bits(&s->pb, 1, 1);

1399 }

1400

1401 /* dynamic range codes */

1402 put_bits(&s->pb, 1, 0);

1403

1404 /* spectral extension */

1405 if (s->eac3)

1406 put_bits(&s->pb, 1, 0);

1407

1408 /* channel coupling */

1409 if (!s->eac3)

1410 put_bits(&s->pb, 1, block->new_cpl_strategy);

1411 if (block->new_cpl_strategy) {

1412 if (!s->eac3)

1413 put_bits(&s->pb, 1, block->cpl_in_use);

1414 if (block->cpl_in_use) {

1415 int start_sub, end_sub;

1416 if (s->eac3)

1417 put_bits(&s->pb, 1, 0); /* enhanced coupling */

1418 if (!s->eac3 || s->channel_mode != AC3_CHMODE_STEREO) {

1419 for (ch = 1; ch <= s->fbw_channels; ch++)

1420 put_bits(&s->pb, 1, block->channel_in_cpl[ch]);

1421 }

1422 if (s->channel_mode == AC3_CHMODE_STEREO)

1423 put_bits(&s->pb, 1, 0); /* phase flags in use */

1424 start_sub = (s->start_freq[CPL_CH] - 37) / 12;

1425 end_sub = (s->cpl_end_freq - 37) / 12;

1426 put_bits(&s->pb, 4, start_sub);

1427 put_bits(&s->pb, 4, end_sub - 3);

1428 /* coupling band structure */

1429 if (s->eac3) {

1430 put_bits(&s->pb, 1, 0); /* use default */

1431 } else {

1432 for (bnd = start_sub+1; bnd < end_sub; bnd++)

1433 put_bits(&s->pb, 1, ff_eac3_default_cpl_band_struct[bnd]);

1434 }

1435 }

1436 }

1437

1438 /* coupling coordinates */

1439 if (block->cpl_in_use) {

1440 for (ch = 1; ch <= s->fbw_channels; ch++) {

1441 if (block->channel_in_cpl[ch]) {

1442 if (!s->eac3 || block->new_cpl_coords[ch] != 2)

1443 put_bits(&s->pb, 1, block->new_cpl_coords[ch]);

1444 if (block->new_cpl_coords[ch]) {

1445 put_bits(&s->pb, 2, block->cpl_master_exp[ch]);

1446 for (bnd = 0; bnd < s->num_cpl_bands; bnd++) {

1447 put_bits(&s->pb, 4, block->cpl_coord_exp [ch][bnd]);

1448 put_bits(&s->pb, 4, block->cpl_coord_mant[ch][bnd]);

1449 }

1450 }

1451 }

1452 }

1453 }

1454

1455 /* stereo rematrixing */

1456 if (s->channel_mode == AC3_CHMODE_STEREO) {

1457 if (!s->eac3 || blk > 0)

1458 put_bits(&s->pb, 1, block->new_rematrixing_strategy);

1459 if (block->new_rematrixing_strategy) {

1460 /* rematrixing flags */

1461 for (bnd = 0; bnd < block->num_rematrixing_bands; bnd++)

1462 put_bits(&s->pb, 1, block->rematrixing_flags[bnd]);

1463 }

1464 }

1465

1466 /* exponent strategy */

1467 if (!s->eac3) {

1468 for (ch = !block->cpl_in_use; ch <= s->fbw_channels; ch++)

1469 put_bits(&s->pb, 2, s->exp_strategy[ch][blk]);

1470 if (s->lfe_on)

1471 put_bits(&s->pb, 1, s->exp_strategy[s->lfe_channel][blk]);

1472 }

1473

1474 /* bandwidth */

1475 for (ch = 1; ch <= s->fbw_channels; ch++) {

1476 if (s->exp_strategy[ch][blk] != EXP_REUSE && !block->channel_in_cpl[ch])

1477 put_bits(&s->pb, 6, s->bandwidth_code);

1478 }

1479

1480 /* exponents */

1481 for (ch = !block->cpl_in_use; ch <= s->channels; ch++) {

1482 int nb_groups;

1483 int cpl = (ch == CPL_CH);

1484

1485 if (s->exp_strategy[ch][blk] == EXP_REUSE)

1486 continue;

1487

1488 /* DC exponent */

1489 put_bits(&s->pb, 4, block->grouped_exp[ch][0] >> cpl);

1490

1491 /* exponent groups */

1492 nb_groups = exponent_group_tab[cpl][s->exp_strategy[ch][blk]-1][block->end_freq[ch]-s->start_freq[ch]];

1493 for (i = 1; i <= nb_groups; i++)

1494 put_bits(&s->pb, 7, block->grouped_exp[ch][i]);

1495

1496 /* gain range info */

1497 if (ch != s->lfe_channel && !cpl)

1498 put_bits(&s->pb, 2, 0);

1499 }

1500

1501 /* bit allocation info */

1502 if (!s->eac3) {

1503 baie = (blk == 0);

1504 put_bits(&s->pb, 1, baie);

1505 if (baie) {

1506 put_bits(&s->pb, 2, s->slow_decay_code);

1507 put_bits(&s->pb, 2, s->fast_decay_code);

1508 put_bits(&s->pb, 2, s->slow_gain_code);

1509 put_bits(&s->pb, 2, s->db_per_bit_code);

1510 put_bits(&s->pb, 3, s->floor_code);

1511 }

1512 }

1513

1514 /* snr offset */

1515 if (!s->eac3) {

1516 put_bits(&s->pb, 1, block->new_snr_offsets);

1517 if (block->new_snr_offsets) {

1518 put_bits(&s->pb, 6, s->coarse_snr_offset);

1519 for (ch = !block->cpl_in_use; ch <= s->channels; ch++) {

1520 put_bits(&s->pb, 4, s->fine_snr_offset[ch]);

1521 put_bits(&s->pb, 3, s->fast_gain_code[ch]);

1522 }

1523 }

1524 } else {

1525 put_bits(&s->pb, 1, 0); /* no converter snr offset */

1526 }

1527

1528 /* coupling leak */

1529 if (block->cpl_in_use) {

1530 if (!s->eac3 || block->new_cpl_leak != 2)

1531 put_bits(&s->pb, 1, block->new_cpl_leak);

1532 if (block->new_cpl_leak) {

1533 put_bits(&s->pb, 3, s->bit_alloc.cpl_fast_leak);

1534 put_bits(&s->pb, 3, s->bit_alloc.cpl_slow_leak);

1535 }

1536 }

1537

1538 if (!s->eac3) {

1539 put_bits(&s->pb, 1, 0); /* no delta bit allocation */

1540 put_bits(&s->pb, 1, 0); /* no data to skip */

1541 }

1542

1543 /* mantissas */

1544 got_cpl = !block->cpl_in_use;

1545 for (ch = 1; ch <= s->channels; ch++) {

1546 int b, q;

1547

1548 if (!got_cpl && ch > 1 && block->channel_in_cpl[ch-1]) {

1549 ch0 = ch - 1;

1550 ch = CPL_CH;

1551 got_cpl = 1;

1552 }

1553 for (i = s->start_freq[ch]; i < block->end_freq[ch]; i++) {

1554 q = block->qmant[ch][i];

1555 b = s->ref_bap[ch][blk][i];

1556 switch (b) {

1557 case 0: break;

1558 case 1: if (q != 128) put_bits (&s->pb, 5, q); break;

1559 case 2: if (q != 128) put_bits (&s->pb, 7, q); break;

1560 case 3: put_sbits(&s->pb, 3, q); break;

1561 case 4: if (q != 128) put_bits (&s->pb, 7, q); break;

1562 case 14: put_sbits(&s->pb, 14, q); break;

1563 case 15: put_sbits(&s->pb, 16, q); break;

1564 default: put_sbits(&s->pb, b-1, q); break;

1565 }

1566 }

1567 if (ch == CPL_CH)

1568 ch = ch0;

1569 }

1570 }

1571

1572

1573 /** CRC-16 Polynomial */

1574 #define CRC16_POLY ((1 << 0) | (1 << 2) | (1 << 15) | (1 << 16))

1575

1576

1577 static unsigned int mul_poly(unsigned int a, unsigned int b, unsigned int poly)

1578 {

1579 unsigned int c;

1580

1581 c = 0;

1582 while (a) {

1583 if (a & 1)

1584 c ^= b;

1585 a = a >> 1;

1586 b = b << 1;

1587 if (b & (1 << 16))

1588 b ^= poly;

1589 }

1590 return c;

1591 }

1592

1593

1594 static unsigned int pow_poly(unsigned int a, unsigned int n, unsigned int poly)

1595 {

1596 unsigned int r;

1597 r = 1;

1598 while (n) {

1599 if (n & 1)

1600 r = mul_poly(r, a, poly);

1601 a = mul_poly(a, a, poly);

1602 n >>= 1;

1603 }

1604 return r;

1605 }

1606

1607

1608 /*

1609 * Fill the end of the frame with 0's and compute the two CRCs.

1610 */

1611 static void output_frame_end(AC3EncodeContext *s)

1612 {

1613 const AVCRC *crc_ctx = av_crc_get_table(AV_CRC_16_ANSI);

1614 int frame_size_58, pad_bytes, crc1, crc2_partial, crc2, crc_inv;

1615 uint8_t *frame;

1616

1617 frame_size_58 = ((s->frame_size >> 2) + (s->frame_size >> 4)) << 1;

1618

1619 /* pad the remainder of the frame with zeros */

1620 av_assert2(s->frame_size * 8 - put_bits_count(&s->pb) >= 18);

1621 flush_put_bits(&s->pb);

1622 frame = s->pb.buf;

1623 pad_bytes = s->frame_size - (put_bits_ptr(&s->pb) - frame) - 2;

1624 av_assert2(pad_bytes >= 0);

1625 if (pad_bytes > 0)

1626 memset(put_bits_ptr(&s->pb), 0, pad_bytes);

1627

1628 if (s->eac3) {

1629 /* compute crc2 */

1630 crc2_partial = av_crc(crc_ctx, 0, frame + 2, s->frame_size - 5);

1631 } else {

1632 /* compute crc1 */

1633 /* this is not so easy because it is at the beginning of the data... */

1634 crc1 = av_bswap16(av_crc(crc_ctx, 0, frame + 4, frame_size_58 - 4));

1635 crc_inv = s->crc_inv[s->frame_size > s->frame_size_min];

1636 crc1 = mul_poly(crc_inv, crc1, CRC16_POLY);

1637 AV_WB16(frame + 2, crc1);

1638

1639 /* compute crc2 */

1640 crc2_partial = av_crc(crc_ctx, 0, frame + frame_size_58,

1641 s->frame_size - frame_size_58 - 3);

1642 }

1643 crc2 = av_crc(crc_ctx, crc2_partial, frame + s->frame_size - 3, 1);

1644 /* ensure crc2 does not match sync word by flipping crcrsv bit if needed */

1645 if (crc2 == 0x770B) {

1646 frame[s->frame_size - 3] ^= 0x1;

1647 crc2 = av_crc(crc_ctx, crc2_partial, frame + s->frame_size - 3, 1);

1648 }

1649 crc2 = av_bswap16(crc2);

1650 AV_WB16(frame + s->frame_size - 2, crc2);

1651 }

1652

1653

1654 /**

1655 * Write the frame to the output bitstream.

1656 *

1657 * @param s AC-3 encoder private context

1658 * @param frame output data buffer

1659 */

1660 void ff_ac3_output_frame(AC3EncodeContext *s, unsigned char *frame)

1661 {

1662 int blk;

1663

1664 init_put_bits(&s->pb, frame, AC3_MAX_CODED_FRAME_SIZE);

1665

1666 s->output_frame_header(s);

1667

1668 for (blk = 0; blk < s->num_blocks; blk++)

1669 output_audio_block(s, blk);

1670

1671 output_frame_end(s);

1672 }

1673

1674

1675 static void dprint_options(AC3EncodeContext *s)

1676 {

1677 #ifdef DEBUG

1678 AVCodecContext *avctx = s->avctx;

1679 AC3EncOptions *opt = &s->options;

1680 char strbuf[32];

1681

1682 switch (s->bitstream_id) {

1683 case 6: av_strlcpy(strbuf, "AC-3 (alt syntax)", 32); break;

1684 case 8: av_strlcpy(strbuf, "AC-3 (standard)", 32); break;

1685 case 9: av_strlcpy(strbuf, "AC-3 (dnet half-rate)", 32); break;

1686 case 10: av_strlcpy(strbuf, "AC-3 (dnet quater-rate)", 32); break;

1687 case 16: av_strlcpy(strbuf, "E-AC-3 (enhanced)", 32); break;

1688 default: snprintf(strbuf, 32, "ERROR");

1689 }

1690 av_dlog(avctx, "bitstream_id: %s (%d)\n", strbuf, s->bitstream_id);

1691 av_dlog(avctx, "sample_fmt: %s\n", av_get_sample_fmt_name(avctx->sample_fmt));

1692 av_get_channel_layout_string(strbuf, 32, s->channels, avctx->channel_layout);

1693 av_dlog(avctx, "channel_layout: %s\n", strbuf);

1694 av_dlog(avctx, "sample_rate: %d\n", s->sample_rate);

1695 av_dlog(avctx, "bit_rate: %d\n", s->bit_rate);

1696 av_dlog(avctx, "blocks/frame: %d (code=%d)\n", s->num_blocks, s->num_blks_code);

1697 if (s->cutoff)

1698 av_dlog(avctx, "cutoff: %d\n", s->cutoff);

1699

1700 av_dlog(avctx, "per_frame_metadata: %s\n",

1701 opt->allow_per_frame_metadata?"on":"off");

1702 if (s->has_center)

1703 av_dlog(avctx, "center_mixlev: %0.3f (%d)\n", opt->center_mix_level,

1704 s->center_mix_level);

1705 else

1706 av_dlog(avctx, "center_mixlev: {not written}\n");

1707 if (s->has_surround)

1708 av_dlog(avctx, "surround_mixlev: %0.3f (%d)\n", opt->surround_mix_level,

1709 s->surround_mix_level);

1710 else

1711 av_dlog(avctx, "surround_mixlev: {not written}\n");

1712 if (opt->audio_production_info) {

1713 av_dlog(avctx, "mixing_level: %ddB\n", opt->mixing_level);

1714 switch (opt->room_type) {

1715 case AC3ENC_OPT_NOT_INDICATED: av_strlcpy(strbuf, "notindicated", 32); break;

1716 case AC3ENC_OPT_LARGE_ROOM: av_strlcpy(strbuf, "large", 32); break;

1717 case AC3ENC_OPT_SMALL_ROOM: av_strlcpy(strbuf, "small", 32); break;

1718 default: snprintf(strbuf, 32, "ERROR (%d)", opt->room_type);

1719 }

1720 av_dlog(avctx, "room_type: %s\n", strbuf);

1721 } else {

1722 av_dlog(avctx, "mixing_level: {not written}\n");

1723 av_dlog(avctx, "room_type: {not written}\n");

1724 }

1725 av_dlog(avctx, "copyright: %s\n", opt->copyright?"on":"off");

1726 av_dlog(avctx, "dialnorm: %ddB\n", opt->dialogue_level);

1727 if (s->channel_mode == AC3_CHMODE_STEREO) {

1728 switch (opt->dolby_surround_mode) {

1729 case AC3ENC_OPT_NOT_INDICATED: av_strlcpy(strbuf, "notindicated", 32); break;

1730 case AC3ENC_OPT_MODE_ON: av_strlcpy(strbuf, "on", 32); break;

1731 case AC3ENC_OPT_MODE_OFF: av_strlcpy(strbuf, "off", 32); break;

1732 default: snprintf(strbuf, 32, "ERROR (%d)", opt->dolby_surround_mode);

1733 }

1734 av_dlog(avctx, "dsur_mode: %s\n", strbuf);

1735 } else {

1736 av_dlog(avctx, "dsur_mode: {not written}\n");

1737 }

1738 av_dlog(avctx, "original: %s\n", opt->original?"on":"off");

1739

1740 if (s->bitstream_id == 6) {

1741 if (opt->extended_bsi_1) {

1742 switch (opt->preferred_stereo_downmix) {

1743 case AC3ENC_OPT_NOT_INDICATED: av_strlcpy(strbuf, "notindicated", 32); break;

1744 case AC3ENC_OPT_DOWNMIX_LTRT: av_strlcpy(strbuf, "ltrt", 32); break;

1745 case AC3ENC_OPT_DOWNMIX_LORO: av_strlcpy(strbuf, "loro", 32); break;

1746 default: snprintf(strbuf, 32, "ERROR (%d)", opt->preferred_stereo_downmix);

1747 }

1748 av_dlog(avctx, "dmix_mode: %s\n", strbuf);

1749 av_dlog(avctx, "ltrt_cmixlev: %0.3f (%d)\n",

1750 opt->ltrt_center_mix_level, s->ltrt_center_mix_level);

1751 av_dlog(avctx, "ltrt_surmixlev: %0.3f (%d)\n",

1752 opt->ltrt_surround_mix_level, s->ltrt_surround_mix_level);

1753 av_dlog(avctx, "loro_cmixlev: %0.3f (%d)\n",

1754 opt->loro_center_mix_level, s->loro_center_mix_level);

1755 av_dlog(avctx, "loro_surmixlev: %0.3f (%d)\n",

1756 opt->loro_surround_mix_level, s->loro_surround_mix_level);

1757 } else {

1758 av_dlog(avctx, "extended bitstream info 1: {not written}\n");

1759 }

1760 if (opt->extended_bsi_2) {

1761 switch (opt->dolby_surround_ex_mode) {

1762 case AC3ENC_OPT_NOT_INDICATED: av_strlcpy(strbuf, "notindicated", 32); break;

1763 case AC3ENC_OPT_MODE_ON: av_strlcpy(strbuf, "on", 32); break;

1764 case AC3ENC_OPT_MODE_OFF: av_strlcpy(strbuf, "off", 32); break;

1765 default: snprintf(strbuf, 32, "ERROR (%d)", opt->dolby_surround_ex_mode);

1766 }

1767 av_dlog(avctx, "dsurex_mode: %s\n", strbuf);

1768 switch (opt->dolby_headphone_mode) {

1769 case AC3ENC_OPT_NOT_INDICATED: av_strlcpy(strbuf, "notindicated", 32); break;

1770 case AC3ENC_OPT_MODE_ON: av_strlcpy(strbuf, "on", 32); break;

1771 case AC3ENC_OPT_MODE_OFF: av_strlcpy(strbuf, "off", 32); break;

1772 default: snprintf(strbuf, 32, "ERROR (%d)", opt->dolby_headphone_mode);

1773 }

1774 av_dlog(avctx, "dheadphone_mode: %s\n", strbuf);

1775

1776 switch (opt->ad_converter_type) {

1777 case AC3ENC_OPT_ADCONV_STANDARD: av_strlcpy(strbuf, "standard", 32); break;

1778 case AC3ENC_OPT_ADCONV_HDCD: av_strlcpy(strbuf, "hdcd", 32); break;

1779 default: snprintf(strbuf, 32, "ERROR (%d)", opt->ad_converter_type);

1780 }

1781 av_dlog(avctx, "ad_conv_type: %s\n", strbuf);

1782 } else {

1783 av_dlog(avctx, "extended bitstream info 2: {not written}\n");

1784 }

1785 }

1786 #endif

1787 }

1788

1789

1790 #define FLT_OPTION_THRESHOLD 0.01

1791

1792 static int validate_float_option(float v, const float *v_list, int v_list_size)

1793 {

1794 int i;

1795

1796 for (i = 0; i < v_list_size; i++) {

1797 if (v < (v_list[i] + FLT_OPTION_THRESHOLD) &&

1798 v > (v_list[i] - FLT_OPTION_THRESHOLD))

1799 break;

1800 }

1801 if (i == v_list_size)

1802 return -1;

1803

1804 return i;

1805 }

1806

1807

1808 static void validate_mix_level(void *log_ctx, const char *opt_name,

1809 float *opt_param, const float *list,

1810 int list_size, int default_value, int min_value,

1811 int *ctx_param)

1812 {

1813 int mixlev = validate_float_option(*opt_param, list, list_size);

1814 if (mixlev < min_value) {

1815 mixlev = default_value;

1816 if (*opt_param >= 0.0) {

1817 av_log(log_ctx, AV_LOG_WARNING, "requested %s is not valid. using "

1818 "default value: %0.3f\n", opt_name, list[mixlev]);

1819 }

1820 }

1821 *opt_param = list[mixlev];

1822 *ctx_param = mixlev;

1823 }

1824

1825

1826 /**

1827 * Validate metadata options as set by AVOption system.

1828 * These values can optionally be changed per-frame.

1829 *

1830 * @param s AC-3 encoder private context

1831 */

1832 int ff_ac3_validate_metadata(AC3EncodeContext *s)

1833 {

1834 AVCodecContext *avctx = s->avctx;

1835 AC3EncOptions *opt = &s->options;

1836

1837 opt->audio_production_info = 0;

1838 opt->extended_bsi_1 = 0;

1839 opt->extended_bsi_2 = 0;

1840 opt->eac3_mixing_metadata = 0;

1841 opt->eac3_info_metadata = 0;

1842

1843 /* determine mixing metadata / xbsi1 use */

1844 if (s->channel_mode > AC3_CHMODE_STEREO && opt->preferred_stereo_downmix != AC3ENC_OPT_NONE) {

1845 opt->extended_bsi_1 = 1;

1846 opt->eac3_mixing_metadata = 1;

1847 }

1848 if (s->has_center &&

1849 (opt->ltrt_center_mix_level >= 0 || opt->loro_center_mix_level >= 0)) {

1850 opt->extended_bsi_1 = 1;

1851 opt->eac3_mixing_metadata = 1;

1852 }

1853 if (s->has_surround &&

1854 (opt->ltrt_surround_mix_level >= 0 || opt->loro_surround_mix_level >= 0)) {

1855 opt->extended_bsi_1 = 1;

1856 opt->eac3_mixing_metadata = 1;

1857 }

1858

1859 if (s->eac3) {

1860 /* determine info metadata use */

1861 if (avctx->audio_service_type != AV_AUDIO_SERVICE_TYPE_MAIN)

1862 opt->eac3_info_metadata = 1;

1863 if (opt->copyright != AC3ENC_OPT_NONE || opt->original != AC3ENC_OPT_NONE)

1864 opt->eac3_info_metadata = 1;

1865 if (s->channel_mode == AC3_CHMODE_STEREO &&

1866 (opt->dolby_headphone_mode != AC3ENC_OPT_NONE || opt->dolby_surround_mode != AC3ENC_OPT_NONE))

1867 opt->eac3_info_metadata = 1;

1868 if (s->channel_mode >= AC3_CHMODE_2F2R && opt->dolby_surround_ex_mode != AC3ENC_OPT_NONE)

1869 opt->eac3_info_metadata = 1;

1870 if (opt->mixing_level != AC3ENC_OPT_NONE || opt->room_type != AC3ENC_OPT_NONE ||

1871 opt->ad_converter_type != AC3ENC_OPT_NONE) {

1872 opt->audio_production_info = 1;

1873 opt->eac3_info_metadata = 1;

1874 }

1875 } else {

1876 /* determine audio production info use */

1877 if (opt->mixing_level != AC3ENC_OPT_NONE || opt->room_type != AC3ENC_OPT_NONE)

1878 opt->audio_production_info = 1;

1879

1880 /* determine xbsi2 use */

1881 if (s->channel_mode >= AC3_CHMODE_2F2R && opt->dolby_surround_ex_mode != AC3ENC_OPT_NONE)

1882 opt->extended_bsi_2 = 1;

1883 if (s->channel_mode == AC3_CHMODE_STEREO && opt->dolby_headphone_mode != AC3ENC_OPT_NONE)

1884 opt->extended_bsi_2 = 1;

1885 if (opt->ad_converter_type != AC3ENC_OPT_NONE)

1886 opt->extended_bsi_2 = 1;

1887 }

1888

1889 /* validate AC-3 mixing levels */

1890 if (!s->eac3) {

1891 if (s->has_center) {

1892 validate_mix_level(avctx, "center_mix_level", &opt->center_mix_level,

1893 cmixlev_options, CMIXLEV_NUM_OPTIONS, 1, 0,

1894 &s->center_mix_level);

1895 }

1896 if (s->has_surround) {

1897 validate_mix_level(avctx, "surround_mix_level", &opt->surround_mix_level,

1898 surmixlev_options, SURMIXLEV_NUM_OPTIONS, 1, 0,

1899 &s->surround_mix_level);

1900 }

1901 }

1902

1903 /* validate extended bsi 1 / mixing metadata */

1904 if (opt->extended_bsi_1 || opt->eac3_mixing_metadata) {

1905 /* default preferred stereo downmix */

1906 if (opt->preferred_stereo_downmix == AC3ENC_OPT_NONE)

1907 opt->preferred_stereo_downmix = AC3ENC_OPT_NOT_INDICATED;

1908 if (!s->eac3 || s->has_center) {

1909 /* validate Lt/Rt center mix level */

1910 validate_mix_level(avctx, "ltrt_center_mix_level",

1911 &opt->ltrt_center_mix_level, extmixlev_options,

1912 EXTMIXLEV_NUM_OPTIONS, 5, 0,

1913 &s->ltrt_center_mix_level);

1914 /* validate Lo/Ro center mix level */

1915 validate_mix_level(avctx, "loro_center_mix_level",

1916 &opt->loro_center_mix_level, extmixlev_options,

1917 EXTMIXLEV_NUM_OPTIONS, 5, 0,

1918 &s->loro_center_mix_level);

1919 }

1920 if (!s->eac3 || s->has_surround) {

1921 /* validate Lt/Rt surround mix level */

1922 validate_mix_level(avctx, "ltrt_surround_mix_level",

1923 &opt->ltrt_surround_mix_level, extmixlev_options,

1924 EXTMIXLEV_NUM_OPTIONS, 6, 3,

1925 &s->ltrt_surround_mix_level);

1926 /* validate Lo/Ro surround mix level */

1927 validate_mix_level(avctx, "loro_surround_mix_level",

1928 &opt->loro_surround_mix_level, extmixlev_options,

1929 EXTMIXLEV_NUM_OPTIONS, 6, 3,

1930 &s->loro_surround_mix_level);

1931 }

1932 }

1933

1934 /* validate audio service type / channels combination */

1935 if ((avctx->audio_service_type == AV_AUDIO_SERVICE_TYPE_KARAOKE &&

1936 avctx->channels == 1) ||

1937 ((avctx->audio_service_type == AV_AUDIO_SERVICE_TYPE_COMMENTARY ||

1938 avctx->audio_service_type == AV_AUDIO_SERVICE_TYPE_EMERGENCY ||

1939 avctx->audio_service_type == AV_AUDIO_SERVICE_TYPE_VOICE_OVER)

1940 && avctx->channels > 1)) {

1941 av_log(avctx, AV_LOG_ERROR, "invalid audio service type for the "

1942 "specified number of channels\n");

1943 return AVERROR(EINVAL);

1944 }

1945

1946 /* validate extended bsi 2 / info metadata */

1947 if (opt->extended_bsi_2 || opt->eac3_info_metadata) {

1948 /* default dolby headphone mode */

1949 if (opt->dolby_headphone_mode == AC3ENC_OPT_NONE)

1950 opt->dolby_headphone_mode = AC3ENC_OPT_NOT_INDICATED;

1951 /* default dolby surround ex mode */

1952 if (opt->dolby_surround_ex_mode == AC3ENC_OPT_NONE)

1953 opt->dolby_surround_ex_mode = AC3ENC_OPT_NOT_INDICATED;

1954 /* default A/D converter type */

1955 if (opt->ad_converter_type == AC3ENC_OPT_NONE)

1956 opt->ad_converter_type = AC3ENC_OPT_ADCONV_STANDARD;

1957 }

1958

1959 /* copyright & original defaults */

1960 if (!s->eac3 || opt->eac3_info_metadata) {

1961 /* default copyright */

1962 if (opt->copyright == AC3ENC_OPT_NONE)

1963 opt->copyright = AC3ENC_OPT_OFF;

1964 /* default original */

1965 if (opt->original == AC3ENC_OPT_NONE)

1966 opt->original = AC3ENC_OPT_ON;

1967 }

1968

1969 /* dolby surround mode default */

1970 if (!s->eac3 || opt->eac3_info_metadata) {

1971 if (opt->dolby_surround_mode == AC3ENC_OPT_NONE)

1972 opt->dolby_surround_mode = AC3ENC_OPT_NOT_INDICATED;

1973 }

1974

1975 /* validate audio production info */

1976 if (opt->audio_production_info) {

1977 if (opt->mixing_level == AC3ENC_OPT_NONE) {

1978 av_log(avctx, AV_LOG_ERROR, "mixing_level must be set if "

1979 "room_type is set\n");

1980 return AVERROR(EINVAL);

1981 }

1982 if (opt->mixing_level < 80) {

1983 av_log(avctx, AV_LOG_ERROR, "invalid mixing level. must be between "

1984 "80dB and 111dB\n");

1985 return AVERROR(EINVAL);

1986 }

1987 /* default room type */

1988 if (opt->room_type == AC3ENC_OPT_NONE)

1989 opt->room_type = AC3ENC_OPT_NOT_INDICATED;

1990 }

1991

1992 /* set bitstream id for alternate bitstream syntax */

1993 if (!s->eac3 && (opt->extended_bsi_1 || opt->extended_bsi_2)) {

1994 if (s->bitstream_id > 8 && s->bitstream_id < 11) {

1995 static int warn_once = 1;

1996 if (warn_once) {

1997 av_log(avctx, AV_LOG_WARNING, "alternate bitstream syntax is "

1998 "not compatible with reduced samplerates. writing of "

1999 "extended bitstream information will be disabled.\n");

2000 warn_once = 0;

2001 }

2002 } else {

2003 s->bitstream_id = 6;

2004 }

2005 }

2006

2007 return 0;

2008 }

2009

2010

2011 /**

2012 * Finalize encoding and free any memory allocated by the encoder.

2013 *

2014 * @param avctx Codec context

2015 */

2016 av_cold int ff_ac3_encode_close(AVCodecContext *avctx)

2017 {

2018 int blk, ch;

2019 AC3EncodeContext *s = avctx->priv_data;

2020

2021 av_freep(&s->windowed_samples);

2022 if (s->planar_samples)

2023 for (ch = 0; ch < s->channels; ch++)

2024 av_freep(&s->planar_samples[ch]);

2025 av_freep(&s->planar_samples);

2026 av_freep(&s->bap_buffer);

2027 av_freep(&s->bap1_buffer);

2028 av_freep(&s->mdct_coef_buffer);

2029 av_freep(&s->fixed_coef_buffer);

2030 av_freep(&s->exp_buffer);

2031 av_freep(&s->grouped_exp_buffer);

2032 av_freep(&s->psd_buffer);

2033 av_freep(&s->band_psd_buffer);

2034 av_freep(&s->mask_buffer);

2035 av_freep(&s->qmant_buffer);

2036 av_freep(&s->cpl_coord_exp_buffer);

2037 av_freep(&s->cpl_coord_mant_buffer);

2038 av_freep(&s->fdsp);

2039 for (blk = 0; blk < s->num_blocks; blk++) {

2040 AC3Block *block = &s->blocks[blk];

2041 av_freep(&block->mdct_coef);

2042 av_freep(&block->fixed_coef);

2043 av_freep(&block->exp);

2044 av_freep(&block->grouped_exp);

2045 av_freep(&block->psd);

2046 av_freep(&block->band_psd);

2047 av_freep(&block->mask);

2048 av_freep(&block->qmant);

2049 av_freep(&block->cpl_coord_exp);

2050 av_freep(&block->cpl_coord_mant);

2051 }

2052

2053 s->mdct_end(s);

2054

2055 return 0;

2056 }

2057

2058

2059 /*

2060 * Set channel information during initialization.

2061 */

2062 static av_cold int set_channel_info(AC3EncodeContext *s, int channels,

2063 uint64_t *channel_layout)

2064 {

2065 int ch_layout;

2066

2067 if (channels < 1 || channels > AC3_MAX_CHANNELS)

2068 return AVERROR(EINVAL);

2069 if (*channel_layout > 0x7FF)

2070 return AVERROR(EINVAL);

2071 ch_layout = *channel_layout;

2072 if (!ch_layout)

2073 ch_layout = av_get_default_channel_layout(channels);

2074

2075 s->lfe_on = !!(ch_layout & AV_CH_LOW_FREQUENCY);

2076 s->channels = channels;

2077 s->fbw_channels = channels - s->lfe_on;

2078 s->lfe_channel = s->lfe_on ? s->fbw_channels + 1 : -1;

2079 if (s->lfe_on)

2080 ch_layout -= AV_CH_LOW_FREQUENCY;

2081

2082 switch (ch_layout) {

2083 case AV_CH_LAYOUT_MONO: s->channel_mode = AC3_CHMODE_MONO; break;

2084 case AV_CH_LAYOUT_STEREO: s->channel_mode = AC3_CHMODE_STEREO; break;

2085 case AV_CH_LAYOUT_SURROUND: s->channel_mode = AC3_CHMODE_3F; break;

2086 case AV_CH_LAYOUT_2_1: s->channel_mode = AC3_CHMODE_2F1R; break;

2087 case AV_CH_LAYOUT_4POINT0: s->channel_mode = AC3_CHMODE_3F1R; break;

2088 case AV_CH_LAYOUT_QUAD:

2089 case AV_CH_LAYOUT_2_2: s->channel_mode = AC3_CHMODE_2F2R; break;

2090 case AV_CH_LAYOUT_5POINT0:

2091 case AV_CH_LAYOUT_5POINT0_BACK: s->channel_mode = AC3_CHMODE_3F2R; break;

2092 default:

2093 return AVERROR(EINVAL);

2094 }

2095 s->has_center = (s->channel_mode & 0x01) && s->channel_mode != AC3_CHMODE_MONO;

2096 s->has_surround = s->channel_mode & 0x04;

2097

2098 s->channel_map = ff_ac3_enc_channel_map[s->channel_mode][s->lfe_on];

2099 *channel_layout = ch_layout;

2100 if (s->lfe_on)

2101 *channel_layout |= AV_CH_LOW_FREQUENCY;

2102

2103 return 0;

2104 }

2105

2106

2107 static av_cold int validate_options(AC3EncodeContext *s)

2108 {

2109 AVCodecContext *avctx = s->avctx;

2110 int i, ret, max_sr;

2111

2112 /* validate channel layout */

2113 if (!avctx->channel_layout) {

2114 av_log(avctx, AV_LOG_WARNING, "No channel layout specified. The "

2115 "encoder will guess the layout, but it "

2116 "might be incorrect.\n");

2117 }

2118 ret = set_channel_info(s, avctx->channels, &avctx->channel_layout);

2119 if (ret) {

2120 av_log(avctx, AV_LOG_ERROR, "invalid channel layout\n");

2121 return ret;

2122 }

2123

2124 /* validate sample rate */

2125 /* note: max_sr could be changed from 2 to 5 for E-AC-3 once we find a

2126 decoder that supports half sample rate so we can validate that

2127 the generated files are correct. */

2128 max_sr = s->eac3 ? 2 : 8;

2129 for (i = 0; i <= max_sr; i++) {

2130 if ((ff_ac3_sample_rate_tab[i % 3] >> (i / 3)) == avctx->sample_rate)

2131 break;

2132 }

2133 if (i > max_sr) {

2134 av_log(avctx, AV_LOG_ERROR, "invalid sample rate\n");

2135 return AVERROR(EINVAL);

2136 }

2137 s->sample_rate = avctx->sample_rate;

2138 s->bit_alloc.sr_shift = i / 3;

2139 s->bit_alloc.sr_code = i % 3;

2140 s->bitstream_id = s->eac3 ? 16 : 8 + s->bit_alloc.sr_shift;

2141

2142 /* select a default bit rate if not set by the user */

2143 if (!avctx->bit_rate) {

2144 switch (s->fbw_channels) {

2145 case 1: avctx->bit_rate = 96000; break;

2146 case 2: avctx->bit_rate = 192000; break;

2147 case 3: avctx->bit_rate = 320000; break;

2148 case 4: avctx->bit_rate = 384000; break;

2149 case 5: avctx->bit_rate = 448000; break;

2150 }

2151 }

2152

2153 /* validate bit rate */

2154 if (s->eac3) {

2155 int max_br, min_br, wpf, min_br_dist, min_br_code;

2156 int num_blks_code, num_blocks, frame_samples;

2157

2158 /* calculate min/max bitrate */

2159 /* TODO: More testing with 3 and 2 blocks. All E-AC-3 samples I've

2160 found use either 6 blocks or 1 block, even though 2 or 3 blocks

2161 would work as far as the bit rate is concerned. */

2162 for (num_blks_code = 3; num_blks_code >= 0; num_blks_code--) {

2163 num_blocks = ((int[]){ 1, 2, 3, 6 })[num_blks_code];

2164 frame_samples = AC3_BLOCK_SIZE * num_blocks;

2165 max_br = 2048 * s->sample_rate / frame_samples * 16;

2166 min_br = ((s->sample_rate + (frame_samples-1)) / frame_samples) * 16;

2167 if (avctx->bit_rate <= max_br)

2168 break;

2169 }

2170 if (avctx->bit_rate < min_br || avctx->bit_rate > max_br) {

2171 av_log(avctx, AV_LOG_ERROR, "invalid bit rate. must be %d to %d "

2172 "for this sample rate\n", min_br, max_br);

2173 return AVERROR(EINVAL);

2174 }

2175 s->num_blks_code = num_blks_code;

2176 s->num_blocks = num_blocks;

2177

2178 /* calculate words-per-frame for the selected bitrate */

2179 wpf = (avctx->bit_rate / 16) * frame_samples / s->sample_rate;

2180 av_assert1(wpf > 0 && wpf <= 2048);

2181

2182 /* find the closest AC-3 bitrate code to the selected bitrate.

2183 this is needed for lookup tables for bandwidth and coupling

2184 parameter selection */

2185 min_br_code = -1;

2186 min_br_dist = INT_MAX;

2187 for (i = 0; i < 19; i++) {

2188 int br_dist = abs(ff_ac3_bitrate_tab[i] * 1000 - avctx->bit_rate);

2189 if (br_dist < min_br_dist) {

2190 min_br_dist = br_dist;

2191 min_br_code = i;

2192 }

2193 }

2194

2195 /* make sure the minimum frame size is below the average frame size */

2196 s->frame_size_code = min_br_code << 1;

2197 while (wpf > 1 && wpf * s->sample_rate / AC3_FRAME_SIZE * 16 > avctx->bit_rate)

2198 wpf--;

2199 s->frame_size_min = 2 * wpf;

2200 } else {

2201 int best_br = 0, best_code = 0, best_diff = INT_MAX;

2202 for (i = 0; i < 19; i++) {

2203 int br = (ff_ac3_bitrate_tab[i] >> s->bit_alloc.sr_shift) * 1000;

2204 int diff = abs(br - avctx->bit_rate);

2205 if (diff < best_diff) {

2206 best_br = br;

2207 best_code = i;

2208 best_diff = diff;

2209 }

2210 if (!best_diff)

2211 break;

2212 }

2213 avctx->bit_rate = best_br;

2214 s->frame_size_code = best_code << 1;

2215 s->frame_size_min = 2 * ff_ac3_frame_size_tab[s->frame_size_code][s->bit_alloc.sr_code];

2216 s->num_blks_code = 0x3;

2217 s->num_blocks = 6;

2218 }

2219 s->bit_rate = avctx->bit_rate;

2220 s->frame_size = s->frame_size_min;

2221

2222 /* validate cutoff */

2223 if (avctx->cutoff < 0) {

2224 av_log(avctx, AV_LOG_ERROR, "invalid cutoff frequency\n");

2225 return AVERROR(EINVAL);

2226 }

2227 s->cutoff = avctx->cutoff;

2228 if (s->cutoff > (s->sample_rate >> 1))

2229 s->cutoff = s->sample_rate >> 1;

2230

2231 ret = ff_ac3_validate_metadata(s);

2232 if (ret)

2233 return ret;

2234

2235 s->rematrixing_enabled = s->options.stereo_rematrixing &&

2236 (s->channel_mode == AC3_CHMODE_STEREO);

2237

2238 s->cpl_enabled = s->options.channel_coupling &&

2239 s->channel_mode >= AC3_CHMODE_STEREO;

2240

2241 return 0;

2242 }

2243

2244

2245 /*

2246 * Set bandwidth for all channels.

2247 * The user can optionally supply a cutoff frequency. Otherwise an appropriate

2248 * default value will be used.

2249 */

2250 static av_cold void set_bandwidth(AC3EncodeContext *s)

2251 {

2252 int blk, ch, av_uninit(cpl_start);

2253

2254 if (s->cutoff) {

2255 /* calculate bandwidth based on user-specified cutoff frequency */

2256 int fbw_coeffs;

2257 fbw_coeffs = s->cutoff * 2 * AC3_MAX_COEFS / s->sample_rate;

2258 s->bandwidth_code = av_clip((fbw_coeffs - 73) / 3, 0, 60);

2259 } else {

2260 /* use default bandwidth setting */

2261 s->bandwidth_code = ac3_bandwidth_tab[s->fbw_channels-1][s->bit_alloc.sr_code][s->frame_size_code/2];

2262 }

2263

2264 /* set number of coefficients for each channel */

2265 for (ch = 1; ch <= s->fbw_channels; ch++) {

2266 s->start_freq[ch] = 0;

2267 for (blk = 0; blk < s->num_blocks; blk++)

2268 s->blocks[blk].end_freq[ch] = s->bandwidth_code * 3 + 73;

2269 }

2270 /* LFE channel always has 7 coefs */

2271 if (s->lfe_on) {

2272 s->start_freq[s->lfe_channel] = 0;

2273 for (blk = 0; blk < s->num_blocks; blk++)

2274 s->blocks[blk].end_freq[ch] = 7;

2275 }

2276

2277 /* initialize coupling strategy */

2278 if (s->cpl_enabled) {

2279 if (s->options.cpl_start != AC3ENC_OPT_AUTO) {

2280 cpl_start = s->options.cpl_start;

2281 } else {

2282 cpl_start = ac3_coupling_start_tab[s->channel_mode-2][s->bit_alloc.sr_code][s->frame_size_code/2];

2283 if (cpl_start < 0) {

2284 if (s->options.channel_coupling == AC3ENC_OPT_AUTO)

2285 s->cpl_enabled = 0;

2286 else

2287 cpl_start = 15;

2288 }

2289 }

2290 }

2291 if (s->cpl_enabled) {

2292 int i, cpl_start_band, cpl_end_band;

2293 uint8_t *cpl_band_sizes = s->cpl_band_sizes;

2294

2295 cpl_end_band = s->bandwidth_code / 4 + 3;

2296 cpl_start_band = av_clip(cpl_start, 0, FFMIN(cpl_end_band-1, 15));

2297

2298 s->num_cpl_subbands = cpl_end_band - cpl_start_band;

2299

2300 s->num_cpl_bands = 1;

2301 *cpl_band_sizes = 12;

2302 for (i = cpl_start_band + 1; i < cpl_end_band; i++) {

2303 if (ff_eac3_default_cpl_band_struct[i]) {

2304 *cpl_band_sizes += 12;

2305 } else {

2306 s->num_cpl_bands++;

2307 cpl_band_sizes++;

2308 *cpl_band_sizes = 12;

2309 }

2310 }

2311

2312 s->start_freq[CPL_CH] = cpl_start_band * 12 + 37;

2313 s->cpl_end_freq = cpl_end_band * 12 + 37;

2314 for (blk = 0; blk < s->num_blocks; blk++)

2315 s->blocks[blk].end_freq[CPL_CH] = s->cpl_end_freq;

2316 }

2317 }

2318

2319

2320 static av_cold int allocate_buffers(AC3EncodeContext *s)

2321 {

2322 AVCodecContext *avctx = s->avctx;

2323 int blk, ch;

2324 int channels = s->channels + 1; /* includes coupling channel */

2325 int channel_blocks = channels * s->num_blocks;

2326 int total_coefs = AC3_MAX_COEFS * channel_blocks;

2327

2328 if (s->allocate_sample_buffers(s))

2329 goto alloc_fail;

2330

2331 FF_ALLOC_ARRAY_OR_GOTO(avctx, s->bap_buffer, total_coefs,

2332 sizeof(*s->bap_buffer), alloc_fail);

2333 FF_ALLOC_ARRAY_OR_GOTO(avctx, s->bap1_buffer, total_coefs,

2334 sizeof(*s->bap1_buffer), alloc_fail);

2335 FF_ALLOCZ_ARRAY_OR_GOTO(avctx, s->mdct_coef_buffer, total_coefs,

2336 sizeof(*s->mdct_coef_buffer), alloc_fail);

2337 FF_ALLOC_ARRAY_OR_GOTO(avctx, s->exp_buffer, total_coefs,

2338 sizeof(*s->exp_buffer), alloc_fail);

2339 FF_ALLOC_ARRAY_OR_GOTO(avctx, s->grouped_exp_buffer, channel_blocks, 128 *

2340 sizeof(*s->grouped_exp_buffer), alloc_fail);

2341 FF_ALLOC_ARRAY_OR_GOTO(avctx, s->psd_buffer, total_coefs,

2342 sizeof(*s->psd_buffer), alloc_fail);

2343 FF_ALLOC_ARRAY_OR_GOTO(avctx, s->band_psd_buffer, channel_blocks, 64 *

2344 sizeof(*s->band_psd_buffer), alloc_fail);

2345 FF_ALLOC_ARRAY_OR_GOTO(avctx, s->mask_buffer, channel_blocks, 64 *

2346 sizeof(*s->mask_buffer), alloc_fail);

2347 FF_ALLOC_ARRAY_OR_GOTO(avctx, s->qmant_buffer, total_coefs,

2348 sizeof(*s->qmant_buffer), alloc_fail);

2349 if (s->cpl_enabled) {

2350 FF_ALLOC_ARRAY_OR_GOTO(avctx, s->cpl_coord_exp_buffer, channel_blocks, 16 *

2351 sizeof(*s->cpl_coord_exp_buffer), alloc_fail);

2352 FF_ALLOC_ARRAY_OR_GOTO(avctx, s->cpl_coord_mant_buffer, channel_blocks, 16 *

2353 sizeof(*s->cpl_coord_mant_buffer), alloc_fail);

2354 }

2355 for (blk = 0; blk < s->num_blocks; blk++) {

2356 AC3Block *block = &s->blocks[blk];

2357 FF_ALLOCZ_ARRAY_OR_GOTO(avctx, block->mdct_coef, channels, sizeof(*block->mdct_coef),

2358 alloc_fail);

2359 FF_ALLOCZ_ARRAY_OR_GOTO(avctx, block->exp, channels, sizeof(*block->exp),

2360 alloc_fail);

2361 FF_ALLOCZ_ARRAY_OR_GOTO(avctx, block->grouped_exp, channels, sizeof(*block->grouped_exp),

2362 alloc_fail);

2363 FF_ALLOCZ_ARRAY_OR_GOTO(avctx, block->psd, channels, sizeof(*block->psd),

2364 alloc_fail);

2365 FF_ALLOCZ_ARRAY_OR_GOTO(avctx, block->band_psd, channels, sizeof(*block->band_psd),

2366 alloc_fail);

2367 FF_ALLOCZ_ARRAY_OR_GOTO(avctx, block->mask, channels, sizeof(*block->mask),

2368 alloc_fail);

2369 FF_ALLOCZ_ARRAY_OR_GOTO(avctx, block->qmant, channels, sizeof(*block->qmant),

2370 alloc_fail);

2371 if (s->cpl_enabled) {

2372 FF_ALLOCZ_ARRAY_OR_GOTO(avctx, block->cpl_coord_exp, channels, sizeof(*block->cpl_coord_exp),

2373 alloc_fail);

2374 FF_ALLOCZ_ARRAY_OR_GOTO(avctx, block->cpl_coord_mant, channels, sizeof(*block->cpl_coord_mant),

2375 alloc_fail);

2376 }

2377

2378 for (ch = 0; ch < channels; ch++) {

2379 /* arrangement: block, channel, coeff */

2380 block->grouped_exp[ch] = &s->grouped_exp_buffer[128 * (blk * channels + ch)];

2381 block->psd[ch] = &s->psd_buffer [AC3_MAX_COEFS * (blk * channels + ch)];

2382 block->band_psd[ch] = &s->band_psd_buffer [64 * (blk * channels + ch)];

2383 block->mask[ch] = &s->mask_buffer [64 * (blk * channels + ch)];

2384 block->qmant[ch] = &s->qmant_buffer [AC3_MAX_COEFS * (blk * channels + ch)];

2385 if (s->cpl_enabled) {

2386 block->cpl_coord_exp[ch] = &s->cpl_coord_exp_buffer [16 * (blk * channels + ch)];

2387 block->cpl_coord_mant[ch] = &s->cpl_coord_mant_buffer[16 * (blk * channels + ch)];

2388 }

2389

2390 /* arrangement: channel, block, coeff */

2391 block->exp[ch] = &s->exp_buffer [AC3_MAX_COEFS * (s->num_blocks * ch + blk)];

2392 block->mdct_coef[ch] = &s->mdct_coef_buffer [AC3_MAX_COEFS * (s->num_blocks * ch + blk)];

2393 }

2394 }

2395

2396 if (!s->fixed_point) {

2397 FF_ALLOCZ_ARRAY_OR_GOTO(avctx, s->fixed_coef_buffer, total_coefs,

2398 sizeof(*s->fixed_coef_buffer), alloc_fail);

2399 for (blk = 0; blk < s->num_blocks; blk++) {

2400 AC3Block *block = &s->blocks[blk];

2401 FF_ALLOCZ_ARRAY_OR_GOTO(avctx, block->fixed_coef, channels,

2402 sizeof(*block->fixed_coef), alloc_fail);

2403 for (ch = 0; ch < channels; ch++)

2404 block->fixed_coef[ch] = &s->fixed_coef_buffer[AC3_MAX_COEFS * (s->num_blocks * ch + blk)];

2405 }

2406 } else {

2407 for (blk = 0; blk < s->num_blocks; blk++) {

2408 AC3Block *block = &s->blocks[blk];

2409 FF_ALLOCZ_ARRAY_OR_GOTO(avctx, block->fixed_coef, channels,

2410 sizeof(*block->fixed_coef), alloc_fail);

2411 for (ch = 0; ch < channels; ch++)

2412 block->fixed_coef[ch] = (int32_t *)block->mdct_coef[ch];

2413 }

2414 }

2415

2416 return 0;

2417 alloc_fail:

2418 return AVERROR(ENOMEM);

2419 }

2420

2421

2422 av_cold int ff_ac3_encode_init(AVCodecContext *avctx)

2423 {

2424 AC3EncodeContext *s = avctx->priv_data;

2425 int ret, frame_size_58;

2426

2427 s->avctx = avctx;

2428

2429 s->eac3 = avctx->codec_id == AV_CODEC_ID_EAC3;

2430

2431 ff_ac3_common_init();

2432

2433 ret = validate_options(s);

2434 if (ret)

2435 return ret;

2436

2437 avctx->frame_size = AC3_BLOCK_SIZE * s->num_blocks;

2438 avctx->initial_padding = AC3_BLOCK_SIZE;

2439

2440 s->bitstream_mode = avctx->audio_service_type;

2441 if (s->bitstream_mode == AV_AUDIO_SERVICE_TYPE_KARAOKE)

2442 s->bitstream_mode = 0x7;

2443

2444 s->bits_written = 0;

2445 s->samples_written = 0;

2446

2447 /* calculate crc_inv for both possible frame sizes */

2448 frame_size_58 = (( s->frame_size >> 2) + ( s->frame_size >> 4)) << 1;

2449 s->crc_inv[0] = pow_poly((CRC16_POLY >> 1), (8 * frame_size_58) - 16, CRC16_POLY);

2450 if (s->bit_alloc.sr_code == 1) {

2451 frame_size_58 = (((s->frame_size+2) >> 2) + ((s->frame_size+2) >> 4)) << 1;

2452 s->crc_inv[1] = pow_poly((CRC16_POLY >> 1), (8 * frame_size_58) - 16, CRC16_POLY);

2453 }

2454

2455 /* set function pointers */

2456 if (CONFIG_AC3_FIXED_ENCODER && s->fixed_point) {

2457 s->mdct_end = ff_ac3_fixed_mdct_end;

2458 s->mdct_init = ff_ac3_fixed_mdct_init;

2459 s->allocate_sample_buffers = ff_ac3_fixed_allocate_sample_buffers;

2460 } else if (CONFIG_AC3_ENCODER || CONFIG_EAC3_ENCODER) {

2461 s->mdct_end = ff_ac3_float_mdct_end;

2462 s->mdct_init = ff_ac3_float_mdct_init;

2463 s->allocate_sample_buffers = ff_ac3_float_allocate_sample_buffers;

2464 }

2465 if (CONFIG_EAC3_ENCODER && s->eac3)

2466 s->output_frame_header = ff_eac3_output_frame_header;

2467 else

2468 s->output_frame_header = ac3_output_frame_header;

2469

2470 set_bandwidth(s);

2471

2472 exponent_init(s);

2473

2474 bit_alloc_init(s);

2475

2476 ret = s->mdct_init(s);

2477 if (ret)

2478 goto init_fail;

2479

2480 ret = allocate_buffers(s);

2481 if (ret)

2482 goto init_fail;

2483

2484 ff_audiodsp_init(&s->adsp);

2485 ff_me_cmp_init(&s->mecc, avctx);

2486 ff_ac3dsp_init(&s->ac3dsp, avctx->flags & CODEC_FLAG_BITEXACT);

2487

2488 dprint_options(s);

2489

2490 return 0;

2491 init_fail:

2492 ff_ac3_encode_close(avctx);

2493 return ret;

2494 }

Generated on Sun Mar 8 2015 02:34:47 for FFmpeg by doxygen 1.8.2