1 /*
2 * Opus encoder
3 * Copyright (c) 2017 Rostislav Pehlivanov <atomnuker@gmail.com>
4 *
5 * This file is part of FFmpeg.
6 *
7 * FFmpeg is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU Lesser General Public
9 * License as published by the Free Software Foundation; either
10 * version 2.1 of the License, or (at your option) any later version.
11 *
12 * FFmpeg is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 * Lesser General Public License for more details.
16 *
17 * You should have received a copy of the GNU Lesser General Public
18 * License along with FFmpeg; if not, write to the Free Software
19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20 */
21
22 #include "opusenc.h"
23 #include "opus_pvq.h"
24 #include "opusenc_psy.h"
25 #include "opustab.h"
26
27 #include "libavutil/float_dsp.h"
28 #include "libavutil/opt.h"
29 #include "internal.h"
30 #include "bytestream.h"
31 #include "audio_frame_queue.h"
32
33 typedef struct OpusEncContext {
34 AVClass *av_class;
35 OpusEncOptions options;
36 OpusPsyContext psyctx;
37 AVCodecContext *avctx;
38 AudioFrameQueue afq;
39 AVFloatDSPContext *dsp;
40 MDCT15Context *mdct[CELT_BLOCK_NB];
41 CeltPVQ *pvq;
42 struct FFBufQueue bufqueue;
43
44 uint8_t enc_id[64];
45 int enc_id_bits;
46
47 OpusPacketInfo packet;
48
49 int channels;
50
51 CeltFrame *frame;
52 OpusRangeCoder *rc;
53
54 /* Actual energy the decoder will have */
55 float last_quantized_energy[OPUS_MAX_CHANNELS][CELT_MAX_BANDS];
56
57 DECLARE_ALIGNED(32, float, scratch)[2048];
58 } OpusEncContext;
59
opus_write_extradata(AVCodecContext * avctx)60 static void opus_write_extradata(AVCodecContext *avctx)
61 {
62 uint8_t *bs = avctx->extradata;
63
64 bytestream_put_buffer(&bs, "OpusHead", 8);
65 bytestream_put_byte (&bs, 0x1);
66 bytestream_put_byte (&bs, avctx->channels);
67 bytestream_put_le16 (&bs, avctx->initial_padding);
68 bytestream_put_le32 (&bs, avctx->sample_rate);
69 bytestream_put_le16 (&bs, 0x0);
70 bytestream_put_byte (&bs, 0x0); /* Default layout */
71 }
72
opus_gen_toc(OpusEncContext * s,uint8_t * toc,int * size,int * fsize_needed)73 static int opus_gen_toc(OpusEncContext *s, uint8_t *toc, int *size, int *fsize_needed)
74 {
75 int tmp = 0x0, extended_toc = 0;
76 static const int toc_cfg[][OPUS_MODE_NB][OPUS_BANDWITH_NB] = {
77 /* Silk Hybrid Celt Layer */
78 /* NB MB WB SWB FB NB MB WB SWB FB NB MB WB SWB FB Bandwidth */
79 { { 0, 0, 0, 0, 0 }, { 0, 0, 0, 0, 0 }, { 17, 0, 21, 25, 29 } }, /* 2.5 ms */
80 { { 0, 0, 0, 0, 0 }, { 0, 0, 0, 0, 0 }, { 18, 0, 22, 26, 30 } }, /* 5 ms */
81 { { 1, 5, 9, 0, 0 }, { 0, 0, 0, 13, 15 }, { 19, 0, 23, 27, 31 } }, /* 10 ms */
82 { { 2, 6, 10, 0, 0 }, { 0, 0, 0, 14, 16 }, { 20, 0, 24, 28, 32 } }, /* 20 ms */
83 { { 3, 7, 11, 0, 0 }, { 0, 0, 0, 0, 0 }, { 0, 0, 0, 0, 0 } }, /* 40 ms */
84 { { 4, 8, 12, 0, 0 }, { 0, 0, 0, 0, 0 }, { 0, 0, 0, 0, 0 } }, /* 60 ms */
85 };
86 int cfg = toc_cfg[s->packet.framesize][s->packet.mode][s->packet.bandwidth];
87 *fsize_needed = 0;
88 if (!cfg)
89 return 1;
90 if (s->packet.frames == 2) { /* 2 packets */
91 if (s->frame[0].framebits == s->frame[1].framebits) { /* same size */
92 tmp = 0x1;
93 } else { /* different size */
94 tmp = 0x2;
95 *fsize_needed = 1; /* put frame sizes in the packet */
96 }
97 } else if (s->packet.frames > 2) {
98 tmp = 0x3;
99 extended_toc = 1;
100 }
101 tmp |= (s->channels > 1) << 2; /* Stereo or mono */
102 tmp |= (cfg - 1) << 3; /* codec configuration */
103 *toc++ = tmp;
104 if (extended_toc) {
105 for (int i = 0; i < (s->packet.frames - 1); i++)
106 *fsize_needed |= (s->frame[i].framebits != s->frame[i + 1].framebits);
107 tmp = (*fsize_needed) << 7; /* vbr flag */
108 tmp |= (0) << 6; /* padding flag */
109 tmp |= s->packet.frames;
110 *toc++ = tmp;
111 }
112 *size = 1 + extended_toc;
113 return 0;
114 }
115
celt_frame_setup_input(OpusEncContext * s,CeltFrame * f)116 static void celt_frame_setup_input(OpusEncContext *s, CeltFrame *f)
117 {
118 AVFrame *cur = NULL;
119 const int subframesize = s->avctx->frame_size;
120 int subframes = OPUS_BLOCK_SIZE(s->packet.framesize) / subframesize;
121
122 cur = ff_bufqueue_get(&s->bufqueue);
123
124 for (int ch = 0; ch < f->channels; ch++) {
125 CeltBlock *b = &f->block[ch];
126 const void *input = cur->extended_data[ch];
127 size_t bps = av_get_bytes_per_sample(cur->format);
128 memcpy(b->overlap, input, bps*cur->nb_samples);
129 }
130
131 av_frame_free(&cur);
132
133 for (int sf = 0; sf < subframes; sf++) {
134 if (sf != (subframes - 1))
135 cur = ff_bufqueue_get(&s->bufqueue);
136 else
137 cur = ff_bufqueue_peek(&s->bufqueue, 0);
138
139 for (int ch = 0; ch < f->channels; ch++) {
140 CeltBlock *b = &f->block[ch];
141 const void *input = cur->extended_data[ch];
142 const size_t bps = av_get_bytes_per_sample(cur->format);
143 const size_t left = (subframesize - cur->nb_samples)*bps;
144 const size_t len = FFMIN(subframesize, cur->nb_samples)*bps;
145 memcpy(&b->samples[sf*subframesize], input, len);
146 memset(&b->samples[cur->nb_samples], 0, left);
147 }
148
149 /* Last frame isn't popped off and freed yet - we need it for overlap */
150 if (sf != (subframes - 1))
151 av_frame_free(&cur);
152 }
153 }
154
155 /* Apply the pre emphasis filter */
celt_apply_preemph_filter(OpusEncContext * s,CeltFrame * f)156 static void celt_apply_preemph_filter(OpusEncContext *s, CeltFrame *f)
157 {
158 const int subframesize = s->avctx->frame_size;
159 const int subframes = OPUS_BLOCK_SIZE(s->packet.framesize) / subframesize;
160
161 /* Filter overlap */
162 for (int ch = 0; ch < f->channels; ch++) {
163 CeltBlock *b = &f->block[ch];
164 float m = b->emph_coeff;
165 for (int i = 0; i < CELT_OVERLAP; i++) {
166 float sample = b->overlap[i];
167 b->overlap[i] = sample - m;
168 m = sample * CELT_EMPH_COEFF;
169 }
170 b->emph_coeff = m;
171 }
172
173 /* Filter the samples but do not update the last subframe's coeff - overlap ^^^ */
174 for (int sf = 0; sf < subframes; sf++) {
175 for (int ch = 0; ch < f->channels; ch++) {
176 CeltBlock *b = &f->block[ch];
177 float m = b->emph_coeff;
178 for (int i = 0; i < subframesize; i++) {
179 float sample = b->samples[sf*subframesize + i];
180 b->samples[sf*subframesize + i] = sample - m;
181 m = sample * CELT_EMPH_COEFF;
182 }
183 if (sf != (subframes - 1))
184 b->emph_coeff = m;
185 }
186 }
187 }
188
189 /* Create the window and do the mdct */
celt_frame_mdct(OpusEncContext * s,CeltFrame * f)190 static void celt_frame_mdct(OpusEncContext *s, CeltFrame *f)
191 {
192 float *win = s->scratch, *temp = s->scratch + 1920;
193
194 if (f->transient) {
195 for (int ch = 0; ch < f->channels; ch++) {
196 CeltBlock *b = &f->block[ch];
197 float *src1 = b->overlap;
198 for (int t = 0; t < f->blocks; t++) {
199 float *src2 = &b->samples[CELT_OVERLAP*t];
200 s->dsp->vector_fmul(win, src1, ff_celt_window, 128);
201 s->dsp->vector_fmul_reverse(&win[CELT_OVERLAP], src2,
202 ff_celt_window - 8, 128);
203 src1 = src2;
204 s->mdct[0]->mdct(s->mdct[0], b->coeffs + t, win, f->blocks);
205 }
206 }
207 } else {
208 int blk_len = OPUS_BLOCK_SIZE(f->size), wlen = OPUS_BLOCK_SIZE(f->size + 1);
209 int rwin = blk_len - CELT_OVERLAP, lap_dst = (wlen - blk_len - CELT_OVERLAP) >> 1;
210 memset(win, 0, wlen*sizeof(float));
211 for (int ch = 0; ch < f->channels; ch++) {
212 CeltBlock *b = &f->block[ch];
213
214 /* Overlap */
215 s->dsp->vector_fmul(temp, b->overlap, ff_celt_window, 128);
216 memcpy(win + lap_dst, temp, CELT_OVERLAP*sizeof(float));
217
218 /* Samples, flat top window */
219 memcpy(&win[lap_dst + CELT_OVERLAP], b->samples, rwin*sizeof(float));
220
221 /* Samples, windowed */
222 s->dsp->vector_fmul_reverse(temp, b->samples + rwin,
223 ff_celt_window - 8, 128);
224 memcpy(win + lap_dst + blk_len, temp, CELT_OVERLAP*sizeof(float));
225
226 s->mdct[f->size]->mdct(s->mdct[f->size], b->coeffs, win, 1);
227 }
228 }
229
230 for (int ch = 0; ch < f->channels; ch++) {
231 CeltBlock *block = &f->block[ch];
232 for (int i = 0; i < CELT_MAX_BANDS; i++) {
233 float ener = 0.0f;
234 int band_offset = ff_celt_freq_bands[i] << f->size;
235 int band_size = ff_celt_freq_range[i] << f->size;
236 float *coeffs = &block->coeffs[band_offset];
237
238 for (int j = 0; j < band_size; j++)
239 ener += coeffs[j]*coeffs[j];
240
241 block->lin_energy[i] = sqrtf(ener) + FLT_EPSILON;
242 ener = 1.0f/block->lin_energy[i];
243
244 for (int j = 0; j < band_size; j++)
245 coeffs[j] *= ener;
246
247 block->energy[i] = log2f(block->lin_energy[i]) - ff_celt_mean_energy[i];
248
249 /* CELT_ENERGY_SILENCE is what the decoder uses and its not -infinity */
250 block->energy[i] = FFMAX(block->energy[i], CELT_ENERGY_SILENCE);
251 }
252 }
253 }
254
celt_enc_tf(CeltFrame * f,OpusRangeCoder * rc)255 static void celt_enc_tf(CeltFrame *f, OpusRangeCoder *rc)
256 {
257 int tf_select = 0, diff = 0, tf_changed = 0, tf_select_needed;
258 int bits = f->transient ? 2 : 4;
259
260 tf_select_needed = ((f->size && (opus_rc_tell(rc) + bits + 1) <= f->framebits));
261
262 for (int i = f->start_band; i < f->end_band; i++) {
263 if ((opus_rc_tell(rc) + bits + tf_select_needed) <= f->framebits) {
264 const int tbit = (diff ^ 1) == f->tf_change[i];
265 ff_opus_rc_enc_log(rc, tbit, bits);
266 diff ^= tbit;
267 tf_changed |= diff;
268 }
269 bits = f->transient ? 4 : 5;
270 }
271
272 if (tf_select_needed && ff_celt_tf_select[f->size][f->transient][0][tf_changed] !=
273 ff_celt_tf_select[f->size][f->transient][1][tf_changed]) {
274 ff_opus_rc_enc_log(rc, f->tf_select, 1);
275 tf_select = f->tf_select;
276 }
277
278 for (int i = f->start_band; i < f->end_band; i++)
279 f->tf_change[i] = ff_celt_tf_select[f->size][f->transient][tf_select][f->tf_change[i]];
280 }
281
celt_enc_quant_pfilter(OpusRangeCoder * rc,CeltFrame * f)282 static void celt_enc_quant_pfilter(OpusRangeCoder *rc, CeltFrame *f)
283 {
284 float gain = f->pf_gain;
285 int txval, octave = f->pf_octave, period = f->pf_period, tapset = f->pf_tapset;
286
287 ff_opus_rc_enc_log(rc, f->pfilter, 1);
288 if (!f->pfilter)
289 return;
290
291 /* Octave */
292 txval = FFMIN(octave, 6);
293 ff_opus_rc_enc_uint(rc, txval, 6);
294 octave = txval;
295 /* Period */
296 txval = av_clip(period - (16 << octave) + 1, 0, (1 << (4 + octave)) - 1);
297 ff_opus_rc_put_raw(rc, period, 4 + octave);
298 period = txval + (16 << octave) - 1;
299 /* Gain */
300 txval = FFMIN(((int)(gain / 0.09375f)) - 1, 7);
301 ff_opus_rc_put_raw(rc, txval, 3);
302 gain = 0.09375f * (txval + 1);
303 /* Tapset */
304 if ((opus_rc_tell(rc) + 2) <= f->framebits)
305 ff_opus_rc_enc_cdf(rc, tapset, ff_celt_model_tapset);
306 else
307 tapset = 0;
308 /* Finally create the coeffs */
309 for (int i = 0; i < 2; i++) {
310 CeltBlock *block = &f->block[i];
311
312 block->pf_period_new = FFMAX(period, CELT_POSTFILTER_MINPERIOD);
313 block->pf_gains_new[0] = gain * ff_celt_postfilter_taps[tapset][0];
314 block->pf_gains_new[1] = gain * ff_celt_postfilter_taps[tapset][1];
315 block->pf_gains_new[2] = gain * ff_celt_postfilter_taps[tapset][2];
316 }
317 }
318
exp_quant_coarse(OpusRangeCoder * rc,CeltFrame * f,float last_energy[][CELT_MAX_BANDS],int intra)319 static void exp_quant_coarse(OpusRangeCoder *rc, CeltFrame *f,
320 float last_energy[][CELT_MAX_BANDS], int intra)
321 {
322 float alpha, beta, prev[2] = { 0, 0 };
323 const uint8_t *pmod = ff_celt_coarse_energy_dist[f->size][intra];
324
325 /* Inter is really just differential coding */
326 if (opus_rc_tell(rc) + 3 <= f->framebits)
327 ff_opus_rc_enc_log(rc, intra, 3);
328 else
329 intra = 0;
330
331 if (intra) {
332 alpha = 0.0f;
333 beta = 1.0f - (4915.0f/32768.0f);
334 } else {
335 alpha = ff_celt_alpha_coef[f->size];
336 beta = ff_celt_beta_coef[f->size];
337 }
338
339 for (int i = f->start_band; i < f->end_band; i++) {
340 for (int ch = 0; ch < f->channels; ch++) {
341 CeltBlock *block = &f->block[ch];
342 const int left = f->framebits - opus_rc_tell(rc);
343 const float last = FFMAX(-9.0f, last_energy[ch][i]);
344 float diff = block->energy[i] - prev[ch] - last*alpha;
345 int q_en = lrintf(diff);
346 if (left >= 15) {
347 ff_opus_rc_enc_laplace(rc, &q_en, pmod[i << 1] << 7, pmod[(i << 1) + 1] << 6);
348 } else if (left >= 2) {
349 q_en = av_clip(q_en, -1, 1);
350 ff_opus_rc_enc_cdf(rc, 2*q_en + 3*(q_en < 0), ff_celt_model_energy_small);
351 } else if (left >= 1) {
352 q_en = av_clip(q_en, -1, 0);
353 ff_opus_rc_enc_log(rc, (q_en & 1), 1);
354 } else q_en = -1;
355
356 block->error_energy[i] = q_en - diff;
357 prev[ch] += beta * q_en;
358 }
359 }
360 }
361
celt_quant_coarse(CeltFrame * f,OpusRangeCoder * rc,float last_energy[][CELT_MAX_BANDS])362 static void celt_quant_coarse(CeltFrame *f, OpusRangeCoder *rc,
363 float last_energy[][CELT_MAX_BANDS])
364 {
365 uint32_t inter, intra;
366 OPUS_RC_CHECKPOINT_SPAWN(rc);
367
368 exp_quant_coarse(rc, f, last_energy, 1);
369 intra = OPUS_RC_CHECKPOINT_BITS(rc);
370
371 OPUS_RC_CHECKPOINT_ROLLBACK(rc);
372
373 exp_quant_coarse(rc, f, last_energy, 0);
374 inter = OPUS_RC_CHECKPOINT_BITS(rc);
375
376 if (inter > intra) { /* Unlikely */
377 OPUS_RC_CHECKPOINT_ROLLBACK(rc);
378 exp_quant_coarse(rc, f, last_energy, 1);
379 }
380 }
381
celt_quant_fine(CeltFrame * f,OpusRangeCoder * rc)382 static void celt_quant_fine(CeltFrame *f, OpusRangeCoder *rc)
383 {
384 for (int i = f->start_band; i < f->end_band; i++) {
385 if (!f->fine_bits[i])
386 continue;
387 for (int ch = 0; ch < f->channels; ch++) {
388 CeltBlock *block = &f->block[ch];
389 int quant, lim = (1 << f->fine_bits[i]);
390 float offset, diff = 0.5f - block->error_energy[i];
391 quant = av_clip(floor(diff*lim), 0, lim - 1);
392 ff_opus_rc_put_raw(rc, quant, f->fine_bits[i]);
393 offset = 0.5f - ((quant + 0.5f) * (1 << (14 - f->fine_bits[i])) / 16384.0f);
394 block->error_energy[i] -= offset;
395 }
396 }
397 }
398
celt_quant_final(OpusEncContext * s,OpusRangeCoder * rc,CeltFrame * f)399 static void celt_quant_final(OpusEncContext *s, OpusRangeCoder *rc, CeltFrame *f)
400 {
401 for (int priority = 0; priority < 2; priority++) {
402 for (int i = f->start_band; i < f->end_band && (f->framebits - opus_rc_tell(rc)) >= f->channels; i++) {
403 if (f->fine_priority[i] != priority || f->fine_bits[i] >= CELT_MAX_FINE_BITS)
404 continue;
405 for (int ch = 0; ch < f->channels; ch++) {
406 CeltBlock *block = &f->block[ch];
407 const float err = block->error_energy[i];
408 const float offset = 0.5f * (1 << (14 - f->fine_bits[i] - 1)) / 16384.0f;
409 const int sign = FFABS(err + offset) < FFABS(err - offset);
410 ff_opus_rc_put_raw(rc, sign, 1);
411 block->error_energy[i] -= offset*(1 - 2*sign);
412 }
413 }
414 }
415 }
416
celt_encode_frame(OpusEncContext * s,OpusRangeCoder * rc,CeltFrame * f,int index)417 static void celt_encode_frame(OpusEncContext *s, OpusRangeCoder *rc,
418 CeltFrame *f, int index)
419 {
420 ff_opus_rc_enc_init(rc);
421
422 ff_opus_psy_celt_frame_init(&s->psyctx, f, index);
423
424 celt_frame_setup_input(s, f);
425
426 if (f->silence) {
427 if (f->framebits >= 16)
428 ff_opus_rc_enc_log(rc, 1, 15); /* Silence (if using explicit singalling) */
429 for (int ch = 0; ch < s->channels; ch++)
430 memset(s->last_quantized_energy[ch], 0.0f, sizeof(float)*CELT_MAX_BANDS);
431 return;
432 }
433
434 /* Filters */
435 celt_apply_preemph_filter(s, f);
436 if (f->pfilter) {
437 ff_opus_rc_enc_log(rc, 0, 15);
438 celt_enc_quant_pfilter(rc, f);
439 }
440
441 /* Transform */
442 celt_frame_mdct(s, f);
443
444 /* Need to handle transient/non-transient switches at any point during analysis */
445 while (ff_opus_psy_celt_frame_process(&s->psyctx, f, index))
446 celt_frame_mdct(s, f);
447
448 ff_opus_rc_enc_init(rc);
449
450 /* Silence */
451 ff_opus_rc_enc_log(rc, 0, 15);
452
453 /* Pitch filter */
454 if (!f->start_band && opus_rc_tell(rc) + 16 <= f->framebits)
455 celt_enc_quant_pfilter(rc, f);
456
457 /* Transient flag */
458 if (f->size && opus_rc_tell(rc) + 3 <= f->framebits)
459 ff_opus_rc_enc_log(rc, f->transient, 3);
460
461 /* Main encoding */
462 celt_quant_coarse (f, rc, s->last_quantized_energy);
463 celt_enc_tf (f, rc);
464 ff_celt_bitalloc (f, rc, 1);
465 celt_quant_fine (f, rc);
466 ff_celt_quant_bands(f, rc);
467
468 /* Anticollapse bit */
469 if (f->anticollapse_needed)
470 ff_opus_rc_put_raw(rc, f->anticollapse, 1);
471
472 /* Final per-band energy adjustments from leftover bits */
473 celt_quant_final(s, rc, f);
474
475 for (int ch = 0; ch < f->channels; ch++) {
476 CeltBlock *block = &f->block[ch];
477 for (int i = 0; i < CELT_MAX_BANDS; i++)
478 s->last_quantized_energy[ch][i] = block->energy[i] + block->error_energy[i];
479 }
480 }
481
write_opuslacing(uint8_t * dst,int v)482 static inline int write_opuslacing(uint8_t *dst, int v)
483 {
484 dst[0] = FFMIN(v - FFALIGN(v - 255, 4), v);
485 dst[1] = v - dst[0] >> 2;
486 return 1 + (v >= 252);
487 }
488
opus_packet_assembler(OpusEncContext * s,AVPacket * avpkt)489 static void opus_packet_assembler(OpusEncContext *s, AVPacket *avpkt)
490 {
491 int offset, fsize_needed;
492
493 /* Write toc */
494 opus_gen_toc(s, avpkt->data, &offset, &fsize_needed);
495
496 /* Frame sizes if needed */
497 if (fsize_needed) {
498 for (int i = 0; i < s->packet.frames - 1; i++) {
499 offset += write_opuslacing(avpkt->data + offset,
500 s->frame[i].framebits >> 3);
501 }
502 }
503
504 /* Packets */
505 for (int i = 0; i < s->packet.frames; i++) {
506 ff_opus_rc_enc_end(&s->rc[i], avpkt->data + offset,
507 s->frame[i].framebits >> 3);
508 offset += s->frame[i].framebits >> 3;
509 }
510
511 avpkt->size = offset;
512 }
513
514 /* Used as overlap for the first frame and padding for the last encoded packet */
spawn_empty_frame(OpusEncContext * s)515 static AVFrame *spawn_empty_frame(OpusEncContext *s)
516 {
517 AVFrame *f = av_frame_alloc();
518 if (!f)
519 return NULL;
520 f->format = s->avctx->sample_fmt;
521 f->nb_samples = s->avctx->frame_size;
522 f->channel_layout = s->avctx->channel_layout;
523 if (av_frame_get_buffer(f, 4)) {
524 av_frame_free(&f);
525 return NULL;
526 }
527 for (int i = 0; i < s->channels; i++) {
528 size_t bps = av_get_bytes_per_sample(f->format);
529 memset(f->extended_data[i], 0, bps*f->nb_samples);
530 }
531 return f;
532 }
533
opus_encode_frame(AVCodecContext * avctx,AVPacket * avpkt,const AVFrame * frame,int * got_packet_ptr)534 static int opus_encode_frame(AVCodecContext *avctx, AVPacket *avpkt,
535 const AVFrame *frame, int *got_packet_ptr)
536 {
537 OpusEncContext *s = avctx->priv_data;
538 int ret, frame_size, alloc_size = 0;
539
540 if (frame) { /* Add new frame to queue */
541 if ((ret = ff_af_queue_add(&s->afq, frame)) < 0)
542 return ret;
543 ff_bufqueue_add(avctx, &s->bufqueue, av_frame_clone(frame));
544 } else {
545 ff_opus_psy_signal_eof(&s->psyctx);
546 if (!s->afq.remaining_samples || !avctx->frame_number)
547 return 0; /* We've been flushed and there's nothing left to encode */
548 }
549
550 /* Run the psychoacoustic system */
551 if (ff_opus_psy_process(&s->psyctx, &s->packet))
552 return 0;
553
554 frame_size = OPUS_BLOCK_SIZE(s->packet.framesize);
555
556 if (!frame) {
557 /* This can go negative, that's not a problem, we only pad if positive */
558 int pad_empty = s->packet.frames*(frame_size/s->avctx->frame_size) - s->bufqueue.available + 1;
559 /* Pad with empty 2.5 ms frames to whatever framesize was decided,
560 * this should only happen at the very last flush frame. The frames
561 * allocated here will be freed (because they have no other references)
562 * after they get used by celt_frame_setup_input() */
563 for (int i = 0; i < pad_empty; i++) {
564 AVFrame *empty = spawn_empty_frame(s);
565 if (!empty)
566 return AVERROR(ENOMEM);
567 ff_bufqueue_add(avctx, &s->bufqueue, empty);
568 }
569 }
570
571 for (int i = 0; i < s->packet.frames; i++) {
572 celt_encode_frame(s, &s->rc[i], &s->frame[i], i);
573 alloc_size += s->frame[i].framebits >> 3;
574 }
575
576 /* Worst case toc + the frame lengths if needed */
577 alloc_size += 2 + s->packet.frames*2;
578
579 if ((ret = ff_alloc_packet2(avctx, avpkt, alloc_size, 0)) < 0)
580 return ret;
581
582 /* Assemble packet */
583 opus_packet_assembler(s, avpkt);
584
585 /* Update the psychoacoustic system */
586 ff_opus_psy_postencode_update(&s->psyctx, s->frame, s->rc);
587
588 /* Remove samples from queue and skip if needed */
589 ff_af_queue_remove(&s->afq, s->packet.frames*frame_size, &avpkt->pts, &avpkt->duration);
590 if (s->packet.frames*frame_size > avpkt->duration) {
591 uint8_t *side = av_packet_new_side_data(avpkt, AV_PKT_DATA_SKIP_SAMPLES, 10);
592 if (!side)
593 return AVERROR(ENOMEM);
594 AV_WL32(&side[4], s->packet.frames*frame_size - avpkt->duration + 120);
595 }
596
597 *got_packet_ptr = 1;
598
599 return 0;
600 }
601
opus_encode_end(AVCodecContext * avctx)602 static av_cold int opus_encode_end(AVCodecContext *avctx)
603 {
604 OpusEncContext *s = avctx->priv_data;
605
606 for (int i = 0; i < CELT_BLOCK_NB; i++)
607 ff_mdct15_uninit(&s->mdct[i]);
608
609 ff_celt_pvq_uninit(&s->pvq);
610 av_freep(&s->dsp);
611 av_freep(&s->frame);
612 av_freep(&s->rc);
613 ff_af_queue_close(&s->afq);
614 ff_opus_psy_end(&s->psyctx);
615 ff_bufqueue_discard_all(&s->bufqueue);
616 av_freep(&avctx->extradata);
617
618 return 0;
619 }
620
opus_encode_init(AVCodecContext * avctx)621 static av_cold int opus_encode_init(AVCodecContext *avctx)
622 {
623 int ret, max_frames;
624 OpusEncContext *s = avctx->priv_data;
625
626 s->avctx = avctx;
627 s->channels = avctx->channels;
628
629 /* Opus allows us to change the framesize on each packet (and each packet may
630 * have multiple frames in it) but we can't change the codec's frame size on
631 * runtime, so fix it to the lowest possible number of samples and use a queue
632 * to accumulate AVFrames until we have enough to encode whatever the encoder
633 * decides is the best */
634 avctx->frame_size = 120;
635 /* Initial padding will change if SILK is ever supported */
636 avctx->initial_padding = 120;
637
638 if (!avctx->bit_rate) {
639 int coupled = ff_opus_default_coupled_streams[s->channels - 1];
640 avctx->bit_rate = coupled*(96000) + (s->channels - coupled*2)*(48000);
641 } else if (avctx->bit_rate < 6000 || avctx->bit_rate > 255000 * s->channels) {
642 int64_t clipped_rate = av_clip(avctx->bit_rate, 6000, 255000 * s->channels);
643 av_log(avctx, AV_LOG_ERROR, "Unsupported bitrate %"PRId64" kbps, clipping to %"PRId64" kbps\n",
644 avctx->bit_rate/1000, clipped_rate/1000);
645 avctx->bit_rate = clipped_rate;
646 }
647
648 /* Extradata */
649 avctx->extradata_size = 19;
650 avctx->extradata = av_malloc(avctx->extradata_size + AV_INPUT_BUFFER_PADDING_SIZE);
651 if (!avctx->extradata)
652 return AVERROR(ENOMEM);
653 opus_write_extradata(avctx);
654
655 ff_af_queue_init(avctx, &s->afq);
656
657 if ((ret = ff_celt_pvq_init(&s->pvq, 1)) < 0)
658 return ret;
659
660 if (!(s->dsp = avpriv_float_dsp_alloc(avctx->flags & AV_CODEC_FLAG_BITEXACT)))
661 return AVERROR(ENOMEM);
662
663 /* I have no idea why a base scaling factor of 68 works, could be the twiddles */
664 for (int i = 0; i < CELT_BLOCK_NB; i++)
665 if ((ret = ff_mdct15_init(&s->mdct[i], 0, i + 3, 68 << (CELT_BLOCK_NB - 1 - i))))
666 return AVERROR(ENOMEM);
667
668 /* Zero out previous energy (matters for inter first frame) */
669 for (int ch = 0; ch < s->channels; ch++)
670 memset(s->last_quantized_energy[ch], 0.0f, sizeof(float)*CELT_MAX_BANDS);
671
672 /* Allocate an empty frame to use as overlap for the first frame of audio */
673 ff_bufqueue_add(avctx, &s->bufqueue, spawn_empty_frame(s));
674 if (!ff_bufqueue_peek(&s->bufqueue, 0))
675 return AVERROR(ENOMEM);
676
677 if ((ret = ff_opus_psy_init(&s->psyctx, s->avctx, &s->bufqueue, &s->options)))
678 return ret;
679
680 /* Frame structs and range coder buffers */
681 max_frames = ceilf(FFMIN(s->options.max_delay_ms, 120.0f)/2.5f);
682 s->frame = av_malloc(max_frames*sizeof(CeltFrame));
683 if (!s->frame)
684 return AVERROR(ENOMEM);
685 s->rc = av_malloc(max_frames*sizeof(OpusRangeCoder));
686 if (!s->rc)
687 return AVERROR(ENOMEM);
688
689 for (int i = 0; i < max_frames; i++) {
690 s->frame[i].dsp = s->dsp;
691 s->frame[i].avctx = s->avctx;
692 s->frame[i].seed = 0;
693 s->frame[i].pvq = s->pvq;
694 s->frame[i].apply_phase_inv = s->options.apply_phase_inv;
695 s->frame[i].block[0].emph_coeff = s->frame[i].block[1].emph_coeff = 0.0f;
696 }
697
698 return 0;
699 }
700
701 #define OPUSENC_FLAGS AV_OPT_FLAG_ENCODING_PARAM | AV_OPT_FLAG_AUDIO_PARAM
702 static const AVOption opusenc_options[] = {
703 { "opus_delay", "Maximum delay in milliseconds", offsetof(OpusEncContext, options.max_delay_ms), AV_OPT_TYPE_FLOAT, { .dbl = OPUS_MAX_LOOKAHEAD }, 2.5f, OPUS_MAX_LOOKAHEAD, OPUSENC_FLAGS, "max_delay_ms" },
704 { "apply_phase_inv", "Apply intensity stereo phase inversion", offsetof(OpusEncContext, options.apply_phase_inv), AV_OPT_TYPE_BOOL, { .i64 = 1 }, 0, 1, OPUSENC_FLAGS, "apply_phase_inv" },
705 { NULL },
706 };
707
708 static const AVClass opusenc_class = {
709 .class_name = "Opus encoder",
710 .item_name = av_default_item_name,
711 .option = opusenc_options,
712 .version = LIBAVUTIL_VERSION_INT,
713 };
714
715 static const AVCodecDefault opusenc_defaults[] = {
716 { "b", "0" },
717 { "compression_level", "10" },
718 { NULL },
719 };
720
721 AVCodec ff_opus_encoder = {
722 .name = "opus",
723 .long_name = NULL_IF_CONFIG_SMALL("Opus"),
724 .type = AVMEDIA_TYPE_AUDIO,
725 .id = AV_CODEC_ID_OPUS,
726 .defaults = opusenc_defaults,
727 .priv_class = &opusenc_class,
728 .priv_data_size = sizeof(OpusEncContext),
729 .init = opus_encode_init,
730 .encode2 = opus_encode_frame,
731 .close = opus_encode_end,
732 .caps_internal = FF_CODEC_CAP_INIT_THREADSAFE | FF_CODEC_CAP_INIT_CLEANUP,
733 .capabilities = AV_CODEC_CAP_SMALL_LAST_FRAME | AV_CODEC_CAP_DELAY,
734 .supported_samplerates = (const int []){ 48000, 0 },
735 .channel_layouts = (const uint64_t []){ AV_CH_LAYOUT_MONO,
736 AV_CH_LAYOUT_STEREO, 0 },
737 .sample_fmts = (const enum AVSampleFormat[]){ AV_SAMPLE_FMT_FLTP,
738 AV_SAMPLE_FMT_NONE },
739 };
740