dsputil: Split audio operations off into a separate context
[libav.git] / libavcodec / ac3enc_template.c
1 /*
2 * AC-3 encoder float/fixed template
3 * Copyright (c) 2000 Fabrice Bellard
4 * Copyright (c) 2006-2011 Justin Ruggles <justin.ruggles@gmail.com>
5 * Copyright (c) 2006-2010 Prakash Punnoor <prakash@punnoor.de>
6 *
7 * This file is part of Libav.
8 *
9 * Libav 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 * Libav 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 Libav; if not, write to the Free Software
21 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
22 */
23
24 /**
25 * @file
26 * AC-3 encoder float/fixed template
27 */
28
29 #include <stdint.h>
30
31 #include "libavutil/attributes.h"
32 #include "libavutil/internal.h"
33
34 #include "audiodsp.h"
35 #include "internal.h"
36 #include "ac3enc.h"
37 #include "eac3enc.h"
38
39 /* prototypes for static functions in ac3enc_fixed.c and ac3enc_float.c */
40
41 static void scale_coefficients(AC3EncodeContext *s);
42
43 static int normalize_samples(AC3EncodeContext *s);
44
45 static void clip_coefficients(AudioDSPContext *adsp, CoefType *coef,
46 unsigned int len);
47
48 static CoefType calc_cpl_coord(CoefSumType energy_ch, CoefSumType energy_cpl);
49
50
51 int AC3_NAME(allocate_sample_buffers)(AC3EncodeContext *s)
52 {
53 int ch;
54
55 FF_ALLOC_OR_GOTO(s->avctx, s->windowed_samples, AC3_WINDOW_SIZE *
56 sizeof(*s->windowed_samples), alloc_fail);
57 FF_ALLOC_OR_GOTO(s->avctx, s->planar_samples, s->channels * sizeof(*s->planar_samples),
58 alloc_fail);
59 for (ch = 0; ch < s->channels; ch++) {
60 FF_ALLOCZ_OR_GOTO(s->avctx, s->planar_samples[ch],
61 (AC3_FRAME_SIZE+AC3_BLOCK_SIZE) * sizeof(**s->planar_samples),
62 alloc_fail);
63 }
64
65 return 0;
66 alloc_fail:
67 return AVERROR(ENOMEM);
68 }
69
70
71 /*
72 * Copy input samples.
73 * Channels are reordered from Libav's default order to AC-3 order.
74 */
75 static void copy_input_samples(AC3EncodeContext *s, SampleType **samples)
76 {
77 int ch;
78
79 /* copy and remap input samples */
80 for (ch = 0; ch < s->channels; ch++) {
81 /* copy last 256 samples of previous frame to the start of the current frame */
82 memcpy(&s->planar_samples[ch][0], &s->planar_samples[ch][AC3_BLOCK_SIZE * s->num_blocks],
83 AC3_BLOCK_SIZE * sizeof(s->planar_samples[0][0]));
84
85 /* copy new samples for current frame */
86 memcpy(&s->planar_samples[ch][AC3_BLOCK_SIZE],
87 samples[s->channel_map[ch]],
88 AC3_BLOCK_SIZE * s->num_blocks * sizeof(s->planar_samples[0][0]));
89 }
90 }
91
92
93 /*
94 * Apply the MDCT to input samples to generate frequency coefficients.
95 * This applies the KBD window and normalizes the input to reduce precision
96 * loss due to fixed-point calculations.
97 */
98 static void apply_mdct(AC3EncodeContext *s)
99 {
100 int blk, ch;
101
102 for (ch = 0; ch < s->channels; ch++) {
103 for (blk = 0; blk < s->num_blocks; blk++) {
104 AC3Block *block = &s->blocks[blk];
105 const SampleType *input_samples = &s->planar_samples[ch][blk * AC3_BLOCK_SIZE];
106
107 #if CONFIG_AC3ENC_FLOAT
108 s->fdsp.vector_fmul(s->windowed_samples, input_samples,
109 s->mdct_window, AC3_WINDOW_SIZE);
110 #else
111 s->ac3dsp.apply_window_int16(s->windowed_samples, input_samples,
112 s->mdct_window, AC3_WINDOW_SIZE);
113 #endif
114
115 if (s->fixed_point)
116 block->coeff_shift[ch+1] = normalize_samples(s);
117
118 s->mdct.mdct_calcw(&s->mdct, block->mdct_coef[ch+1],
119 s->windowed_samples);
120 }
121 }
122 }
123
124
125 /*
126 * Calculate coupling channel and coupling coordinates.
127 */
128 static void apply_channel_coupling(AC3EncodeContext *s)
129 {
130 LOCAL_ALIGNED_16(CoefType, cpl_coords, [AC3_MAX_BLOCKS], [AC3_MAX_CHANNELS][16]);
131 #if CONFIG_AC3ENC_FLOAT
132 LOCAL_ALIGNED_16(int32_t, fixed_cpl_coords, [AC3_MAX_BLOCKS], [AC3_MAX_CHANNELS][16]);
133 #else
134 int32_t (*fixed_cpl_coords)[AC3_MAX_CHANNELS][16] = cpl_coords;
135 #endif
136 int blk, ch, bnd, i, j;
137 CoefSumType energy[AC3_MAX_BLOCKS][AC3_MAX_CHANNELS][16] = {{{0}}};
138 int cpl_start, num_cpl_coefs;
139
140 memset(cpl_coords, 0, AC3_MAX_BLOCKS * sizeof(*cpl_coords));
141 #if CONFIG_AC3ENC_FLOAT
142 memset(fixed_cpl_coords, 0, AC3_MAX_BLOCKS * sizeof(*cpl_coords));
143 #endif
144
145 /* align start to 16-byte boundary. align length to multiple of 32.
146 note: coupling start bin % 4 will always be 1 */
147 cpl_start = s->start_freq[CPL_CH] - 1;
148 num_cpl_coefs = FFALIGN(s->num_cpl_subbands * 12 + 1, 32);
149 cpl_start = FFMIN(256, cpl_start + num_cpl_coefs) - num_cpl_coefs;
150
151 /* calculate coupling channel from fbw channels */
152 for (blk = 0; blk < s->num_blocks; blk++) {
153 AC3Block *block = &s->blocks[blk];
154 CoefType *cpl_coef = &block->mdct_coef[CPL_CH][cpl_start];
155 if (!block->cpl_in_use)
156 continue;
157 memset(cpl_coef, 0, num_cpl_coefs * sizeof(*cpl_coef));
158 for (ch = 1; ch <= s->fbw_channels; ch++) {
159 CoefType *ch_coef = &block->mdct_coef[ch][cpl_start];
160 if (!block->channel_in_cpl[ch])
161 continue;
162 for (i = 0; i < num_cpl_coefs; i++)
163 cpl_coef[i] += ch_coef[i];
164 }
165
166 /* coefficients must be clipped in order to be encoded */
167 clip_coefficients(&s->adsp, cpl_coef, num_cpl_coefs);
168 }
169
170 /* calculate energy in each band in coupling channel and each fbw channel */
171 /* TODO: possibly use SIMD to speed up energy calculation */
172 bnd = 0;
173 i = s->start_freq[CPL_CH];
174 while (i < s->cpl_end_freq) {
175 int band_size = s->cpl_band_sizes[bnd];
176 for (ch = CPL_CH; ch <= s->fbw_channels; ch++) {
177 for (blk = 0; blk < s->num_blocks; blk++) {
178 AC3Block *block = &s->blocks[blk];
179 if (!block->cpl_in_use || (ch > CPL_CH && !block->channel_in_cpl[ch]))
180 continue;
181 for (j = 0; j < band_size; j++) {
182 CoefType v = block->mdct_coef[ch][i+j];
183 MAC_COEF(energy[blk][ch][bnd], v, v);
184 }
185 }
186 }
187 i += band_size;
188 bnd++;
189 }
190
191 /* calculate coupling coordinates for all blocks for all channels */
192 for (blk = 0; blk < s->num_blocks; blk++) {
193 AC3Block *block = &s->blocks[blk];
194 if (!block->cpl_in_use)
195 continue;
196 for (ch = 1; ch <= s->fbw_channels; ch++) {
197 if (!block->channel_in_cpl[ch])
198 continue;
199 for (bnd = 0; bnd < s->num_cpl_bands; bnd++) {
200 cpl_coords[blk][ch][bnd] = calc_cpl_coord(energy[blk][ch][bnd],
201 energy[blk][CPL_CH][bnd]);
202 }
203 }
204 }
205
206 /* determine which blocks to send new coupling coordinates for */
207 for (blk = 0; blk < s->num_blocks; blk++) {
208 AC3Block *block = &s->blocks[blk];
209 AC3Block *block0 = blk ? &s->blocks[blk-1] : NULL;
210
211 memset(block->new_cpl_coords, 0, sizeof(block->new_cpl_coords));
212
213 if (block->cpl_in_use) {
214 /* send new coordinates if this is the first block, if previous
215 * block did not use coupling but this block does, the channels
216 * using coupling has changed from the previous block, or the
217 * coordinate difference from the last block for any channel is
218 * greater than a threshold value. */
219 if (blk == 0 || !block0->cpl_in_use) {
220 for (ch = 1; ch <= s->fbw_channels; ch++)
221 block->new_cpl_coords[ch] = 1;
222 } else {
223 for (ch = 1; ch <= s->fbw_channels; ch++) {
224 if (!block->channel_in_cpl[ch])
225 continue;
226 if (!block0->channel_in_cpl[ch]) {
227 block->new_cpl_coords[ch] = 1;
228 } else {
229 CoefSumType coord_diff = 0;
230 for (bnd = 0; bnd < s->num_cpl_bands; bnd++) {
231 coord_diff += FFABS(cpl_coords[blk-1][ch][bnd] -
232 cpl_coords[blk ][ch][bnd]);
233 }
234 coord_diff /= s->num_cpl_bands;
235 if (coord_diff > NEW_CPL_COORD_THRESHOLD)
236 block->new_cpl_coords[ch] = 1;
237 }
238 }
239 }
240 }
241 }
242
243 /* calculate final coupling coordinates, taking into account reusing of
244 coordinates in successive blocks */
245 for (bnd = 0; bnd < s->num_cpl_bands; bnd++) {
246 blk = 0;
247 while (blk < s->num_blocks) {
248 int av_uninit(blk1);
249 AC3Block *block = &s->blocks[blk];
250
251 if (!block->cpl_in_use) {
252 blk++;
253 continue;
254 }
255
256 for (ch = 1; ch <= s->fbw_channels; ch++) {
257 CoefSumType energy_ch, energy_cpl;
258 if (!block->channel_in_cpl[ch])
259 continue;
260 energy_cpl = energy[blk][CPL_CH][bnd];
261 energy_ch = energy[blk][ch][bnd];
262 blk1 = blk+1;
263 while (!s->blocks[blk1].new_cpl_coords[ch] && blk1 < s->num_blocks) {
264 if (s->blocks[blk1].cpl_in_use) {
265 energy_cpl += energy[blk1][CPL_CH][bnd];
266 energy_ch += energy[blk1][ch][bnd];
267 }
268 blk1++;
269 }
270 cpl_coords[blk][ch][bnd] = calc_cpl_coord(energy_ch, energy_cpl);
271 }
272 blk = blk1;
273 }
274 }
275
276 /* calculate exponents/mantissas for coupling coordinates */
277 for (blk = 0; blk < s->num_blocks; blk++) {
278 AC3Block *block = &s->blocks[blk];
279 if (!block->cpl_in_use)
280 continue;
281
282 #if CONFIG_AC3ENC_FLOAT
283 s->ac3dsp.float_to_fixed24(fixed_cpl_coords[blk][1],
284 cpl_coords[blk][1],
285 s->fbw_channels * 16);
286 #endif
287 s->ac3dsp.extract_exponents(block->cpl_coord_exp[1],
288 fixed_cpl_coords[blk][1],
289 s->fbw_channels * 16);
290
291 for (ch = 1; ch <= s->fbw_channels; ch++) {
292 int bnd, min_exp, max_exp, master_exp;
293
294 if (!block->new_cpl_coords[ch])
295 continue;
296
297 /* determine master exponent */
298 min_exp = max_exp = block->cpl_coord_exp[ch][0];
299 for (bnd = 1; bnd < s->num_cpl_bands; bnd++) {
300 int exp = block->cpl_coord_exp[ch][bnd];
301 min_exp = FFMIN(exp, min_exp);
302 max_exp = FFMAX(exp, max_exp);
303 }
304 master_exp = ((max_exp - 15) + 2) / 3;
305 master_exp = FFMAX(master_exp, 0);
306 while (min_exp < master_exp * 3)
307 master_exp--;
308 for (bnd = 0; bnd < s->num_cpl_bands; bnd++) {
309 block->cpl_coord_exp[ch][bnd] = av_clip(block->cpl_coord_exp[ch][bnd] -
310 master_exp * 3, 0, 15);
311 }
312 block->cpl_master_exp[ch] = master_exp;
313
314 /* quantize mantissas */
315 for (bnd = 0; bnd < s->num_cpl_bands; bnd++) {
316 int cpl_exp = block->cpl_coord_exp[ch][bnd];
317 int cpl_mant = (fixed_cpl_coords[blk][ch][bnd] << (5 + cpl_exp + master_exp * 3)) >> 24;
318 if (cpl_exp == 15)
319 cpl_mant >>= 1;
320 else
321 cpl_mant -= 16;
322
323 block->cpl_coord_mant[ch][bnd] = cpl_mant;
324 }
325 }
326 }
327
328 if (CONFIG_EAC3_ENCODER && s->eac3)
329 ff_eac3_set_cpl_states(s);
330 }
331
332
333 /*
334 * Determine rematrixing flags for each block and band.
335 */
336 static void compute_rematrixing_strategy(AC3EncodeContext *s)
337 {
338 int nb_coefs;
339 int blk, bnd, i;
340 AC3Block *block, *block0;
341
342 if (s->channel_mode != AC3_CHMODE_STEREO)
343 return;
344
345 for (blk = 0; blk < s->num_blocks; blk++) {
346 block = &s->blocks[blk];
347 block->new_rematrixing_strategy = !blk;
348
349 block->num_rematrixing_bands = 4;
350 if (block->cpl_in_use) {
351 block->num_rematrixing_bands -= (s->start_freq[CPL_CH] <= 61);
352 block->num_rematrixing_bands -= (s->start_freq[CPL_CH] == 37);
353 if (blk && block->num_rematrixing_bands != block0->num_rematrixing_bands)
354 block->new_rematrixing_strategy = 1;
355 }
356 nb_coefs = FFMIN(block->end_freq[1], block->end_freq[2]);
357
358 if (!s->rematrixing_enabled) {
359 block0 = block;
360 continue;
361 }
362
363 for (bnd = 0; bnd < block->num_rematrixing_bands; bnd++) {
364 /* calculate calculate sum of squared coeffs for one band in one block */
365 int start = ff_ac3_rematrix_band_tab[bnd];
366 int end = FFMIN(nb_coefs, ff_ac3_rematrix_band_tab[bnd+1]);
367 CoefSumType sum[4] = {0,};
368 for (i = start; i < end; i++) {
369 CoefType lt = block->mdct_coef[1][i];
370 CoefType rt = block->mdct_coef[2][i];
371 CoefType md = lt + rt;
372 CoefType sd = lt - rt;
373 MAC_COEF(sum[0], lt, lt);
374 MAC_COEF(sum[1], rt, rt);
375 MAC_COEF(sum[2], md, md);
376 MAC_COEF(sum[3], sd, sd);
377 }
378
379 /* compare sums to determine if rematrixing will be used for this band */
380 if (FFMIN(sum[2], sum[3]) < FFMIN(sum[0], sum[1]))
381 block->rematrixing_flags[bnd] = 1;
382 else
383 block->rematrixing_flags[bnd] = 0;
384
385 /* determine if new rematrixing flags will be sent */
386 if (blk &&
387 block->rematrixing_flags[bnd] != block0->rematrixing_flags[bnd]) {
388 block->new_rematrixing_strategy = 1;
389 }
390 }
391 block0 = block;
392 }
393 }
394
395
396 int AC3_NAME(encode_frame)(AVCodecContext *avctx, AVPacket *avpkt,
397 const AVFrame *frame, int *got_packet_ptr)
398 {
399 AC3EncodeContext *s = avctx->priv_data;
400 int ret;
401
402 if (s->options.allow_per_frame_metadata) {
403 ret = ff_ac3_validate_metadata(s);
404 if (ret)
405 return ret;
406 }
407
408 if (s->bit_alloc.sr_code == 1 || s->eac3)
409 ff_ac3_adjust_frame_size(s);
410
411 copy_input_samples(s, (SampleType **)frame->extended_data);
412
413 apply_mdct(s);
414
415 if (s->fixed_point)
416 scale_coefficients(s);
417
418 clip_coefficients(&s->adsp, s->blocks[0].mdct_coef[1],
419 AC3_MAX_COEFS * s->num_blocks * s->channels);
420
421 s->cpl_on = s->cpl_enabled;
422 ff_ac3_compute_coupling_strategy(s);
423
424 if (s->cpl_on)
425 apply_channel_coupling(s);
426
427 compute_rematrixing_strategy(s);
428
429 if (!s->fixed_point)
430 scale_coefficients(s);
431
432 ff_ac3_apply_rematrixing(s);
433
434 ff_ac3_process_exponents(s);
435
436 ret = ff_ac3_compute_bit_allocation(s);
437 if (ret) {
438 av_log(avctx, AV_LOG_ERROR, "Bit allocation failed. Try increasing the bitrate.\n");
439 return ret;
440 }
441
442 ff_ac3_group_exponents(s);
443
444 ff_ac3_quantize_mantissas(s);
445
446 if ((ret = ff_alloc_packet(avpkt, s->frame_size))) {
447 av_log(avctx, AV_LOG_ERROR, "Error getting output packet\n");
448 return ret;
449 }
450 ff_ac3_output_frame(s, avpkt->data);
451
452 if (frame->pts != AV_NOPTS_VALUE)
453 avpkt->pts = frame->pts - ff_samples_to_time_base(avctx, avctx->delay);
454
455 *got_packet_ptr = 1;
456 return 0;
457 }