FFmpeg coverage

Line	Branch	Exec	Source
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 <float.h>
23
24			#include "encode.h"
25			#include "enc.h"
26			#include "pvq.h"
27			#include "enc_psy.h"
28			#include "tab.h"
29
30			#include "libavutil/channel_layout.h"
31			#include "libavutil/float_dsp.h"
32			#include "libavutil/mem.h"
33			#include "libavutil/mem_internal.h"
34			#include "libavutil/opt.h"
35			#include "bytestream.h"
36			#include "audio_frame_queue.h"
37			#include "codec_internal.h"
38
39			typedef struct OpusEncContext {
40			AVClass *av_class;
41			OpusEncOptions options;
42			OpusPsyContext psyctx;
43			AVCodecContext *avctx;
44			AudioFrameQueue afq;
45			AVFloatDSPContext *dsp;
46			AVTXContext *tx[CELT_BLOCK_NB];
47			av_tx_fn tx_fn[CELT_BLOCK_NB];
48			CeltPVQ *pvq;
49			struct FFBufQueue bufqueue;
50
51			uint8_t enc_id[64];
52			int enc_id_bits;
53
54			OpusPacketInfo packet;
55
56			int channels;
57
58			CeltFrame *frame;
59			OpusRangeCoder *rc;
60
61			/* Actual energy the decoder will have */
62			float last_quantized_energy[OPUS_MAX_CHANNELS][CELT_MAX_BANDS];
63
64			DECLARE_ALIGNED(32, float, scratch)[2048];
65			} OpusEncContext;
66
67		✗	static void opus_write_extradata(AVCodecContext *avctx)
68			{
69		✗	uint8_t *bs = avctx->extradata;
70
71		✗	bytestream_put_buffer(&bs, "OpusHead", 8);
72		✗	bytestream_put_byte (&bs, 0x1);
73		✗	bytestream_put_byte (&bs, avctx->ch_layout.nb_channels);
74		✗	bytestream_put_le16 (&bs, avctx->initial_padding);
75		✗	bytestream_put_le32 (&bs, avctx->sample_rate);
76		✗	bytestream_put_le16 (&bs, 0x0);
77		✗	bytestream_put_byte (&bs, 0x0); /* Default layout */
78		✗	}
79
80		✗	static int opus_gen_toc(OpusEncContext *s, uint8_t *toc, int *size, int *fsize_needed)
81			{
82		✗	int tmp = 0x0, extended_toc = 0;
83			static const int toc_cfg[][OPUS_MODE_NB][OPUS_BANDWITH_NB] = {
84			/* Silk Hybrid Celt Layer */
85			/* NB MB WB SWB FB NB MB WB SWB FB NB MB WB SWB FB Bandwidth */
86			{ { 0, 0, 0, 0, 0 }, { 0, 0, 0, 0, 0 }, { 17, 0, 21, 25, 29 } }, /* 2.5 ms */
87			{ { 0, 0, 0, 0, 0 }, { 0, 0, 0, 0, 0 }, { 18, 0, 22, 26, 30 } }, /* 5 ms */
88			{ { 1, 5, 9, 0, 0 }, { 0, 0, 0, 13, 15 }, { 19, 0, 23, 27, 31 } }, /* 10 ms */
89			{ { 2, 6, 10, 0, 0 }, { 0, 0, 0, 14, 16 }, { 20, 0, 24, 28, 32 } }, /* 20 ms */
90			{ { 3, 7, 11, 0, 0 }, { 0, 0, 0, 0, 0 }, { 0, 0, 0, 0, 0 } }, /* 40 ms */
91			{ { 4, 8, 12, 0, 0 }, { 0, 0, 0, 0, 0 }, { 0, 0, 0, 0, 0 } }, /* 60 ms */
92			};
93		✗	int cfg = toc_cfg[s->packet.framesize][s->packet.mode][s->packet.bandwidth];
94		✗	*fsize_needed = 0;
95		✗	if (!cfg)
96		✗	return 1;
97		✗	if (s->packet.frames == 2) { /* 2 packets */
98		✗	if (s->frame[0].framebits == s->frame[1].framebits) { /* same size */
99		✗	tmp = 0x1;
100			} else { /* different size */
101		✗	tmp = 0x2;
102		✗	*fsize_needed = 1; /* put frame sizes in the packet */
103			}
104		✗	} else if (s->packet.frames > 2) {
105		✗	tmp = 0x3;
106		✗	extended_toc = 1;
107			}
108		✗	tmp |= (s->channels > 1) << 2; /* Stereo or mono */
109		✗	tmp |= (cfg - 1) << 3; /* codec configuration */
110		✗	*toc++ = tmp;
111		✗	if (extended_toc) {
112		✗	for (int i = 0; i < (s->packet.frames - 1); i++)
113		✗	*fsize_needed |= (s->frame[i].framebits != s->frame[i + 1].framebits);
114		✗	tmp = (*fsize_needed) << 7; /* vbr flag */
115		✗	tmp |= (0) << 6; /* padding flag */
116		✗	tmp |= s->packet.frames;
117		✗	*toc++ = tmp;
118			}
119		✗	*size = 1 + extended_toc;
120		✗	return 0;
121			}
122
123		✗	static void celt_frame_setup_input(OpusEncContext *s, CeltFrame *f)
124			{
125		✗	AVFrame *cur = NULL;
126		✗	const int subframesize = s->avctx->frame_size;
127		✗	int subframes = OPUS_BLOCK_SIZE(s->packet.framesize) / subframesize;
128
129		✗	cur = ff_bufqueue_get(&s->bufqueue);
130
131		✗	for (int ch = 0; ch < f->channels; ch++) {
132		✗	CeltBlock *b = &f->block[ch];
133		✗	const void *input = cur->extended_data[ch];
134		✗	size_t bps = av_get_bytes_per_sample(cur->format);
135		✗	memcpy(b->overlap, input, bps*cur->nb_samples);
136			}
137
138		✗	av_frame_free(&cur);
139
140		✗	for (int sf = 0; sf < subframes; sf++) {
141		✗	if (sf != (subframes - 1))
142		✗	cur = ff_bufqueue_get(&s->bufqueue);
143			else
144		✗	cur = ff_bufqueue_peek(&s->bufqueue, 0);
145
146		✗	for (int ch = 0; ch < f->channels; ch++) {
147		✗	CeltBlock *b = &f->block[ch];
148		✗	const void *input = cur->extended_data[ch];
149		✗	const size_t bps = av_get_bytes_per_sample(cur->format);
150		✗	const size_t left = (subframesize - cur->nb_samples)*bps;
151		✗	const size_t len = FFMIN(subframesize, cur->nb_samples)*bps;
152		✗	memcpy(&b->samples[sf*subframesize], input, len);
153		✗	memset(&b->samples[cur->nb_samples], 0, left);
154			}
155
156			/* Last frame isn't popped off and freed yet - we need it for overlap */
157		✗	if (sf != (subframes - 1))
158		✗	av_frame_free(&cur);
159			}
160		✗	}
161
162			/* Apply the pre emphasis filter */
163		✗	static void celt_apply_preemph_filter(OpusEncContext *s, CeltFrame *f)
164			{
165		✗	const int subframesize = s->avctx->frame_size;
166		✗	const int subframes = OPUS_BLOCK_SIZE(s->packet.framesize) / subframesize;
167		✗	const float c = ff_opus_deemph_weights[0];
168
169			/* Filter overlap */
170		✗	for (int ch = 0; ch < f->channels; ch++) {
171		✗	CeltBlock *b = &f->block[ch];
172		✗	float m = b->emph_coeff;
173		✗	for (int i = 0; i < CELT_OVERLAP; i++) {
174		✗	float sample = b->overlap[i];
175		✗	b->overlap[i] = sample - m;
176		✗	m = sample * c;
177			}
178		✗	b->emph_coeff = m;
179			}
180
181			/* Filter the samples but do not update the last subframe's coeff - overlap ^^^ */
182		✗	for (int sf = 0; sf < subframes; sf++) {
183		✗	for (int ch = 0; ch < f->channels; ch++) {
184		✗	CeltBlock *b = &f->block[ch];
185		✗	float m = b->emph_coeff;
186		✗	for (int i = 0; i < subframesize; i++) {
187		✗	float sample = b->samples[sf*subframesize + i];
188		✗	b->samples[sf*subframesize + i] = sample - m;
189		✗	m = sample * c;
190			}
191		✗	if (sf != (subframes - 1))
192		✗	b->emph_coeff = m;
193			}
194			}
195		✗	}
196
197			/* Create the window and do the mdct */
198		✗	static void celt_frame_mdct(OpusEncContext *s, CeltFrame *f)
199			{
200		✗	float *win = s->scratch, *temp = s->scratch + 1920;
201
202		✗	if (f->transient) {
203		✗	for (int ch = 0; ch < f->channels; ch++) {
204		✗	CeltBlock *b = &f->block[ch];
205		✗	float *src1 = b->overlap;
206		✗	for (int t = 0; t < f->blocks; t++) {
207		✗	float *src2 = &b->samples[CELT_OVERLAP*t];
208		✗	s->dsp->vector_fmul(win, src1, ff_celt_window, 128);
209		✗	s->dsp->vector_fmul_reverse(&win[CELT_OVERLAP], src2,
210			ff_celt_window_padded, 128);
211		✗	src1 = src2;
212		✗	s->tx_fn[0](s->tx[0], b->coeffs + t, win, sizeof(float)*f->blocks);
213			}
214			}
215			} else {
216		✗	int blk_len = OPUS_BLOCK_SIZE(f->size), wlen = OPUS_BLOCK_SIZE(f->size + 1);
217		✗	int rwin = blk_len - CELT_OVERLAP, lap_dst = (wlen - blk_len - CELT_OVERLAP) >> 1;
218		✗	memset(win, 0, wlen*sizeof(float));
219		✗	for (int ch = 0; ch < f->channels; ch++) {
220		✗	CeltBlock *b = &f->block[ch];
221
222			/* Overlap */
223		✗	s->dsp->vector_fmul(temp, b->overlap, ff_celt_window, 128);
224		✗	memcpy(win + lap_dst, temp, CELT_OVERLAP*sizeof(float));
225
226			/* Samples, flat top window */
227		✗	memcpy(&win[lap_dst + CELT_OVERLAP], b->samples, rwin*sizeof(float));
228
229			/* Samples, windowed */
230		✗	s->dsp->vector_fmul_reverse(temp, b->samples + rwin,
231			ff_celt_window_padded, 128);
232		✗	memcpy(win + lap_dst + blk_len, temp, CELT_OVERLAP*sizeof(float));
233
234		✗	s->tx_fn[f->size](s->tx[f->size], b->coeffs, win, sizeof(float));
235			}
236			}
237
238		✗	for (int ch = 0; ch < f->channels; ch++) {
239		✗	CeltBlock *block = &f->block[ch];
240		✗	for (int i = 0; i < CELT_MAX_BANDS; i++) {
241		✗	float ener = 0.0f;
242		✗	int band_offset = ff_celt_freq_bands[i] << f->size;
243		✗	int band_size = ff_celt_freq_range[i] << f->size;
244		✗	float *coeffs = &block->coeffs[band_offset];
245
246		✗	for (int j = 0; j < band_size; j++)
247		✗	ener += coeffs[j]*coeffs[j];
248
249		✗	block->lin_energy[i] = sqrtf(ener) + FLT_EPSILON;
250		✗	ener = 1.0f/block->lin_energy[i];
251
252		✗	for (int j = 0; j < band_size; j++)
253		✗	coeffs[j] *= ener;
254
255		✗	block->energy[i] = log2f(block->lin_energy[i]) - ff_celt_mean_energy[i];
256
257			/* CELT_ENERGY_SILENCE is what the decoder uses and its not -infinity */
258		✗	block->energy[i] = FFMAX(block->energy[i], CELT_ENERGY_SILENCE);
259			}
260			}
261		✗	}
262
263		✗	static void celt_enc_tf(CeltFrame *f, OpusRangeCoder *rc)
264			{
265		✗	int tf_select = 0, diff = 0, tf_changed = 0, tf_select_needed;
266		✗	int bits = f->transient ? 2 : 4;
267
268		✗	tf_select_needed = ((f->size && (opus_rc_tell(rc) + bits + 1) <= f->framebits));
269
270		✗	for (int i = f->start_band; i < f->end_band; i++) {
271		✗	if ((opus_rc_tell(rc) + bits + tf_select_needed) <= f->framebits) {
272		✗	const int tbit = (diff ^ 1) == f->tf_change[i];
273		✗	ff_opus_rc_enc_log(rc, tbit, bits);
274		✗	diff ^= tbit;
275		✗	tf_changed |= diff;
276			}
277		✗	bits = f->transient ? 4 : 5;
278			}
279
280		✗	if (tf_select_needed && ff_celt_tf_select[f->size][f->transient][0][tf_changed] !=
281		✗	ff_celt_tf_select[f->size][f->transient][1][tf_changed]) {
282		✗	ff_opus_rc_enc_log(rc, f->tf_select, 1);
283		✗	tf_select = f->tf_select;
284			}
285
286		✗	for (int i = f->start_band; i < f->end_band; i++)
287		✗	f->tf_change[i] = ff_celt_tf_select[f->size][f->transient][tf_select][f->tf_change[i]];
288		✗	}
289
290		✗	static void celt_enc_quant_pfilter(OpusRangeCoder *rc, CeltFrame *f)
291			{
292		✗	float gain = f->pf_gain;
293		✗	int txval, octave = f->pf_octave, period = f->pf_period, tapset = f->pf_tapset;
294
295		✗	ff_opus_rc_enc_log(rc, f->pfilter, 1);
296		✗	if (!f->pfilter)
297		✗	return;
298
299			/* Octave */
300		✗	txval = FFMIN(octave, 6);
301		✗	ff_opus_rc_enc_uint(rc, txval, 6);
302		✗	octave = txval;
303			/* Period */
304		✗	txval = av_clip(period - (16 << octave) + 1, 0, (1 << (4 + octave)) - 1);
305		✗	ff_opus_rc_put_raw(rc, period, 4 + octave);
306		✗	period = txval + (16 << octave) - 1;
307			/* Gain */
308		✗	txval = FFMIN(((int)(gain / 0.09375f)) - 1, 7);
309		✗	ff_opus_rc_put_raw(rc, txval, 3);
310		✗	gain = 0.09375f * (txval + 1);
311			/* Tapset */
312		✗	if ((opus_rc_tell(rc) + 2) <= f->framebits)
313		✗	ff_opus_rc_enc_cdf(rc, tapset, ff_celt_model_tapset);
314			else
315		✗	tapset = 0;
316			/* Finally create the coeffs */
317		✗	for (int i = 0; i < 2; i++) {
318		✗	CeltBlock *block = &f->block[i];
319
320		✗	block->pf_period_new = FFMAX(period, CELT_POSTFILTER_MINPERIOD);
321		✗	block->pf_gains_new[0] = gain * ff_celt_postfilter_taps[tapset][0];
322		✗	block->pf_gains_new[1] = gain * ff_celt_postfilter_taps[tapset][1];
323		✗	block->pf_gains_new[2] = gain * ff_celt_postfilter_taps[tapset][2];
324			}
325			}
326
327		✗	static void exp_quant_coarse(OpusRangeCoder *rc, CeltFrame *f,
328			float last_energy[][CELT_MAX_BANDS], int intra)
329			{
330		✗	float alpha, beta, prev[2] = { 0, 0 };
331		✗	const uint8_t *pmod = ff_celt_coarse_energy_dist[f->size][intra];
332
333			/* Inter is really just differential coding */
334		✗	if (opus_rc_tell(rc) + 3 <= f->framebits)
335		✗	ff_opus_rc_enc_log(rc, intra, 3);
336			else
337		✗	intra = 0;
338
339		✗	if (intra) {
340		✗	alpha = 0.0f;
341		✗	beta = 1.0f - (4915.0f/32768.0f);
342			} else {
343		✗	alpha = ff_celt_alpha_coef[f->size];
344		✗	beta = ff_celt_beta_coef[f->size];
345			}
346
347		✗	for (int i = f->start_band; i < f->end_band; i++) {
348		✗	for (int ch = 0; ch < f->channels; ch++) {
349		✗	CeltBlock *block = &f->block[ch];
350		✗	const int left = f->framebits - opus_rc_tell(rc);
351		✗	const float last = FFMAX(-9.0f, last_energy[ch][i]);
352		✗	float diff = block->energy[i] - prev[ch] - last*alpha;
353		✗	int q_en = lrintf(diff);
354		✗	if (left >= 15) {
355		✗	ff_opus_rc_enc_laplace(rc, &q_en, pmod[i << 1] << 7, pmod[(i << 1) + 1] << 6);
356		✗	} else if (left >= 2) {
357		✗	q_en = av_clip(q_en, -1, 1);
358		✗	ff_opus_rc_enc_cdf(rc, 2*q_en + 3*(q_en < 0), ff_celt_model_energy_small);
359		✗	} else if (left >= 1) {
360		✗	q_en = av_clip(q_en, -1, 0);
361		✗	ff_opus_rc_enc_log(rc, (q_en & 1), 1);
362		✗	} else q_en = -1;
363
364		✗	block->error_energy[i] = q_en - diff;
365		✗	prev[ch] += beta * q_en;
366			}
367			}
368		✗	}
369
370		✗	static void celt_quant_coarse(CeltFrame *f, OpusRangeCoder *rc,
371			float last_energy[][CELT_MAX_BANDS])
372			{
373			uint32_t inter, intra;
374		✗	OPUS_RC_CHECKPOINT_SPAWN(rc);
375
376		✗	exp_quant_coarse(rc, f, last_energy, 1);
377		✗	intra = OPUS_RC_CHECKPOINT_BITS(rc);
378
379		✗	OPUS_RC_CHECKPOINT_ROLLBACK(rc);
380
381		✗	exp_quant_coarse(rc, f, last_energy, 0);
382		✗	inter = OPUS_RC_CHECKPOINT_BITS(rc);
383
384		✗	if (inter > intra) { /* Unlikely */
385		✗	OPUS_RC_CHECKPOINT_ROLLBACK(rc);
386		✗	exp_quant_coarse(rc, f, last_energy, 1);
387			}
388		✗	}
389
390		✗	static void celt_quant_fine(CeltFrame *f, OpusRangeCoder *rc)
391			{
392		✗	for (int i = f->start_band; i < f->end_band; i++) {
393		✗	if (!f->fine_bits[i])
394		✗	continue;
395		✗	for (int ch = 0; ch < f->channels; ch++) {
396		✗	CeltBlock *block = &f->block[ch];
397		✗	int quant, lim = (1 << f->fine_bits[i]);
398		✗	float offset, diff = 0.5f - block->error_energy[i];
399		✗	quant = av_clip(floor(diff*lim), 0, lim - 1);
400		✗	ff_opus_rc_put_raw(rc, quant, f->fine_bits[i]);
401		✗	offset = 0.5f - ((quant + 0.5f) * (1 << (14 - f->fine_bits[i])) / 16384.0f);
402		✗	block->error_energy[i] -= offset;
403			}
404			}
405		✗	}
406
407		✗	static void celt_quant_final(OpusEncContext *s, OpusRangeCoder *rc, CeltFrame *f)
408			{
409		✗	for (int priority = 0; priority < 2; priority++) {
410		✗	for (int i = f->start_band; i < f->end_band && (f->framebits - opus_rc_tell(rc)) >= f->channels; i++) {
411		✗	if (f->fine_priority[i] != priority || f->fine_bits[i] >= CELT_MAX_FINE_BITS)
412		✗	continue;
413		✗	for (int ch = 0; ch < f->channels; ch++) {
414		✗	CeltBlock *block = &f->block[ch];
415		✗	const float err = block->error_energy[i];
416		✗	const float offset = 0.5f * (1 << (14 - f->fine_bits[i] - 1)) / 16384.0f;
417		✗	const int sign = FFABS(err + offset) < FFABS(err - offset);
418		✗	ff_opus_rc_put_raw(rc, sign, 1);
419		✗	block->error_energy[i] -= offset*(1 - 2*sign);
420			}
421			}
422			}
423		✗	}
424
425		✗	static void celt_encode_frame(OpusEncContext *s, OpusRangeCoder *rc,
426			CeltFrame *f, int index)
427			{
428		✗	ff_opus_rc_enc_init(rc);
429
430		✗	ff_opus_psy_celt_frame_init(&s->psyctx, f, index);
431
432		✗	celt_frame_setup_input(s, f);
433
434		✗	if (f->silence) {
435		✗	if (f->framebits >= 16)
436		✗	ff_opus_rc_enc_log(rc, 1, 15); /* Silence (if using explicit singalling) */
437		✗	for (int ch = 0; ch < s->channels; ch++)
438		✗	memset(s->last_quantized_energy[ch], 0.0f, sizeof(float)*CELT_MAX_BANDS);
439		✗	return;
440			}
441
442			/* Filters */
443		✗	celt_apply_preemph_filter(s, f);
444		✗	if (f->pfilter) {
445		✗	ff_opus_rc_enc_log(rc, 0, 15);
446		✗	celt_enc_quant_pfilter(rc, f);
447			}
448
449			/* Transform */
450		✗	celt_frame_mdct(s, f);
451
452			/* Need to handle transient/non-transient switches at any point during analysis */
453		✗	while (ff_opus_psy_celt_frame_process(&s->psyctx, f, index))
454		✗	celt_frame_mdct(s, f);
455
456		✗	ff_opus_rc_enc_init(rc);
457
458			/* Silence */
459		✗	ff_opus_rc_enc_log(rc, 0, 15);
460
461			/* Pitch filter */
462		✗	if (!f->start_band && opus_rc_tell(rc) + 16 <= f->framebits)
463		✗	celt_enc_quant_pfilter(rc, f);
464
465			/* Transient flag */
466		✗	if (f->size && opus_rc_tell(rc) + 3 <= f->framebits)
467		✗	ff_opus_rc_enc_log(rc, f->transient, 3);
468
469			/* Main encoding */
470		✗	celt_quant_coarse (f, rc, s->last_quantized_energy);
471		✗	celt_enc_tf (f, rc);
472		✗	ff_celt_bitalloc (f, rc, 1);
473		✗	celt_quant_fine (f, rc);
474		✗	ff_celt_quant_bands(f, rc);
475
476			/* Anticollapse bit */
477		✗	if (f->anticollapse_needed)
478		✗	ff_opus_rc_put_raw(rc, f->anticollapse, 1);
479
480			/* Final per-band energy adjustments from leftover bits */
481		✗	celt_quant_final(s, rc, f);
482
483		✗	for (int ch = 0; ch < f->channels; ch++) {
484		✗	CeltBlock *block = &f->block[ch];
485		✗	for (int i = 0; i < CELT_MAX_BANDS; i++)
486		✗	s->last_quantized_energy[ch][i] = block->energy[i] + block->error_energy[i];
487			}
488			}
489
490		✗	static inline int write_opuslacing(uint8_t *dst, int v)
491			{
492		✗	dst[0] = FFMIN(v - FFALIGN(v - 255, 4), v);
493		✗	dst[1] = v - dst[0] >> 2;
494		✗	return 1 + (v >= 252);
495			}
496
497		✗	static void opus_packet_assembler(OpusEncContext *s, AVPacket *avpkt)
498			{
499			int offset, fsize_needed;
500
501			/* Write toc */
502		✗	opus_gen_toc(s, avpkt->data, &offset, &fsize_needed);
503
504			/* Frame sizes if needed */
505		✗	if (fsize_needed) {
506		✗	for (int i = 0; i < s->packet.frames - 1; i++) {
507		✗	offset += write_opuslacing(avpkt->data + offset,
508		✗	s->frame[i].framebits >> 3);
509			}
510			}
511
512			/* Packets */
513		✗	for (int i = 0; i < s->packet.frames; i++) {
514		✗	ff_opus_rc_enc_end(&s->rc[i], avpkt->data + offset,
515		✗	s->frame[i].framebits >> 3);
516		✗	offset += s->frame[i].framebits >> 3;
517			}
518
519		✗	avpkt->size = offset;
520		✗	}
521
522			/* Used as overlap for the first frame and padding for the last encoded packet */
523		✗	static AVFrame *spawn_empty_frame(OpusEncContext *s)
524			{
525		✗	AVFrame *f = av_frame_alloc();
526			int ret;
527		✗	if (!f)
528		✗	return NULL;
529		✗	f->format = s->avctx->sample_fmt;
530		✗	f->nb_samples = s->avctx->frame_size;
531		✗	ret = av_channel_layout_copy(&f->ch_layout, &s->avctx->ch_layout);
532		✗	if (ret < 0) {
533		✗	av_frame_free(&f);
534		✗	return NULL;
535			}
536		✗	if (av_frame_get_buffer(f, 4)) {
537		✗	av_frame_free(&f);
538		✗	return NULL;
539			}
540		✗	for (int i = 0; i < s->channels; i++) {
541		✗	size_t bps = av_get_bytes_per_sample(f->format);
542		✗	memset(f->extended_data[i], 0, bps*f->nb_samples);
543			}
544		✗	return f;
545			}
546
547		✗	static int opus_encode_frame(AVCodecContext *avctx, AVPacket *avpkt,
548			const AVFrame *frame, int *got_packet_ptr)
549			{
550		✗	OpusEncContext *s = avctx->priv_data;
551		✗	int ret, frame_size, alloc_size = 0;
552
553		✗	if (frame) { /* Add new frame to queue */
554		✗	if ((ret = ff_af_queue_add(&s->afq, frame)) < 0)
555		✗	return ret;
556		✗	ff_bufqueue_add(avctx, &s->bufqueue, av_frame_clone(frame));
557			} else {
558		✗	ff_opus_psy_signal_eof(&s->psyctx);
559		✗	if (!s->afq.remaining_samples || !avctx->frame_num)
560		✗	return 0; /* We've been flushed and there's nothing left to encode */
561			}
562
563			/* Run the psychoacoustic system */
564		✗	if (ff_opus_psy_process(&s->psyctx, &s->packet))
565		✗	return 0;
566
567		✗	frame_size = OPUS_BLOCK_SIZE(s->packet.framesize);
568
569		✗	if (!frame) {
570			/* This can go negative, that's not a problem, we only pad if positive */
571		✗	int pad_empty = s->packet.frames*(frame_size/s->avctx->frame_size) - s->bufqueue.available + 1;
572			/* Pad with empty 2.5 ms frames to whatever framesize was decided,
573			* this should only happen at the very last flush frame. The frames
574			* allocated here will be freed (because they have no other references)
575			* after they get used by celt_frame_setup_input() */
576		✗	for (int i = 0; i < pad_empty; i++) {
577		✗	AVFrame *empty = spawn_empty_frame(s);
578		✗	if (!empty)
579		✗	return AVERROR(ENOMEM);
580		✗	ff_bufqueue_add(avctx, &s->bufqueue, empty);
581			}
582			}
583
584		✗	for (int i = 0; i < s->packet.frames; i++) {
585		✗	celt_encode_frame(s, &s->rc[i], &s->frame[i], i);
586		✗	alloc_size += s->frame[i].framebits >> 3;
587			}
588
589			/* Worst case toc + the frame lengths if needed */
590		✗	alloc_size += 2 + s->packet.frames*2;
591
592		✗	if ((ret = ff_alloc_packet(avctx, avpkt, alloc_size)) < 0)
593		✗	return ret;
594
595			/* Assemble packet */
596		✗	opus_packet_assembler(s, avpkt);
597
598			/* Update the psychoacoustic system */
599		✗	ff_opus_psy_postencode_update(&s->psyctx, s->frame);
600
601			/* Remove samples from queue and skip if needed */
602		✗	ff_af_queue_remove(&s->afq, s->packet.frames*frame_size, &avpkt->pts, &avpkt->duration);
603		✗	if (s->packet.frames*frame_size > avpkt->duration) {
604		✗	uint8_t *side = av_packet_new_side_data(avpkt, AV_PKT_DATA_SKIP_SAMPLES, 10);
605		✗	if (!side)
606		✗	return AVERROR(ENOMEM);
607		✗	AV_WL32(&side[4], s->packet.frames*frame_size - avpkt->duration + 120);
608			}
609
610		✗	*got_packet_ptr = 1;
611
612		✗	return 0;
613			}
614
615		✗	static av_cold int opus_encode_end(AVCodecContext *avctx)
616			{
617		✗	OpusEncContext *s = avctx->priv_data;
618
619		✗	for (int i = 0; i < CELT_BLOCK_NB; i++)
620		✗	av_tx_uninit(&s->tx[i]);
621
622		✗	ff_celt_pvq_uninit(&s->pvq);
623		✗	av_freep(&s->dsp);
624		✗	av_freep(&s->frame);
625		✗	av_freep(&s->rc);
626		✗	ff_af_queue_close(&s->afq);
627		✗	ff_opus_psy_end(&s->psyctx);
628		✗	ff_bufqueue_discard_all(&s->bufqueue);
629
630		✗	return 0;
631			}
632
633		✗	static av_cold int opus_encode_init(AVCodecContext *avctx)
634			{
635			int ret, max_frames;
636		✗	OpusEncContext *s = avctx->priv_data;
637
638		✗	s->avctx = avctx;
639		✗	s->channels = avctx->ch_layout.nb_channels;
640
641			/* Opus allows us to change the framesize on each packet (and each packet may
642			* have multiple frames in it) but we can't change the codec's frame size on
643			* runtime, so fix it to the lowest possible number of samples and use a queue
644			* to accumulate AVFrames until we have enough to encode whatever the encoder
645			* decides is the best */
646		✗	avctx->frame_size = 120;
647			/* Initial padding will change if SILK is ever supported */
648		✗	avctx->initial_padding = 120;
649
650		✗	if (!avctx->bit_rate) {
651		✗	int coupled = ff_opus_default_coupled_streams[s->channels - 1];
652		✗	avctx->bit_rate = coupled*(96000) + (s->channels - coupled*2)*(48000);
653		✗	} else if (avctx->bit_rate < 6000 || avctx->bit_rate > 255000 * s->channels) {
654		✗	int64_t clipped_rate = av_clip(avctx->bit_rate, 6000, 255000 * s->channels);
655		✗	av_log(avctx, AV_LOG_ERROR, "Unsupported bitrate %"PRId64" kbps, clipping to %"PRId64" kbps\n",
656		✗	avctx->bit_rate/1000, clipped_rate/1000);
657		✗	avctx->bit_rate = clipped_rate;
658			}
659
660			/* Extradata */
661		✗	avctx->extradata_size = 19;
662		✗	avctx->extradata = av_malloc(avctx->extradata_size + AV_INPUT_BUFFER_PADDING_SIZE);
663		✗	if (!avctx->extradata)
664		✗	return AVERROR(ENOMEM);
665		✗	opus_write_extradata(avctx);
666
667		✗	ff_af_queue_init(avctx, &s->afq);
668
669		✗	if ((ret = ff_celt_pvq_init(&s->pvq, 1)) < 0)
670		✗	return ret;
671
672		✗	if (!(s->dsp = avpriv_float_dsp_alloc(avctx->flags & AV_CODEC_FLAG_BITEXACT)))
673		✗	return AVERROR(ENOMEM);
674
675			/* I have no idea why a base scaling factor of 68 works, could be the twiddles */
676		✗	for (int i = 0; i < CELT_BLOCK_NB; i++) {
677		✗	const float scale = 68 << (CELT_BLOCK_NB - 1 - i);
678		✗	if ((ret = av_tx_init(&s->tx[i], &s->tx_fn[i], AV_TX_FLOAT_MDCT, 0, 15 << (i + 3), &scale, 0)))
679		✗	return AVERROR(ENOMEM);
680			}
681
682			/* Zero out previous energy (matters for inter first frame) */
683		✗	for (int ch = 0; ch < s->channels; ch++)
684		✗	memset(s->last_quantized_energy[ch], 0.0f, sizeof(float)*CELT_MAX_BANDS);
685
686			/* Allocate an empty frame to use as overlap for the first frame of audio */
687		✗	ff_bufqueue_add(avctx, &s->bufqueue, spawn_empty_frame(s));
688		✗	if (!ff_bufqueue_peek(&s->bufqueue, 0))
689		✗	return AVERROR(ENOMEM);
690
691		✗	if ((ret = ff_opus_psy_init(&s->psyctx, s->avctx, &s->bufqueue, &s->options)))
692		✗	return ret;
693
694			/* Frame structs and range coder buffers */
695		✗	max_frames = ceilf(FFMIN(s->options.max_delay_ms, 120.0f)/2.5f);
696		✗	s->frame = av_malloc(max_frames*sizeof(CeltFrame));
697		✗	if (!s->frame)
698		✗	return AVERROR(ENOMEM);
699		✗	s->rc = av_malloc(max_frames*sizeof(OpusRangeCoder));
700		✗	if (!s->rc)
701		✗	return AVERROR(ENOMEM);
702
703		✗	for (int i = 0; i < max_frames; i++) {
704		✗	s->frame[i].dsp = s->dsp;
705		✗	s->frame[i].avctx = s->avctx;
706		✗	s->frame[i].seed = 0;
707		✗	s->frame[i].pvq = s->pvq;
708		✗	s->frame[i].apply_phase_inv = s->options.apply_phase_inv;
709		✗	s->frame[i].block[0].emph_coeff = s->frame[i].block[1].emph_coeff = 0.0f;
710			}
711
712		✗	return 0;
713			}
714
715			#define OPUSENC_FLAGS AV_OPT_FLAG_ENCODING_PARAM | AV_OPT_FLAG_AUDIO_PARAM
716			static const AVOption opusenc_options[] = {
717			{ "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, .unit = "max_delay_ms" },
718			{ "apply_phase_inv", "Apply intensity stereo phase inversion", offsetof(OpusEncContext, options.apply_phase_inv), AV_OPT_TYPE_BOOL, { .i64 = 1 }, 0, 1, OPUSENC_FLAGS, .unit = "apply_phase_inv" },
719			{ NULL },
720			};
721
722			static const AVClass opusenc_class = {
723			.class_name = "Opus encoder",
724			.item_name = av_default_item_name,
725			.option = opusenc_options,
726			.version = LIBAVUTIL_VERSION_INT,
727			};
728
729			static const FFCodecDefault opusenc_defaults[] = {
730			{ "b", "0" },
731			{ "compression_level", "10" },
732			{ NULL },
733			};
734
735			const FFCodec ff_opus_encoder = {
736			.p.name = "opus",
737			CODEC_LONG_NAME("Opus"),
738			.p.type = AVMEDIA_TYPE_AUDIO,
739			.p.id = AV_CODEC_ID_OPUS,
740			.p.capabilities = AV_CODEC_CAP_DR1 | AV_CODEC_CAP_DELAY |
741			AV_CODEC_CAP_SMALL_LAST_FRAME | AV_CODEC_CAP_EXPERIMENTAL,
742			.defaults = opusenc_defaults,
743			.p.priv_class = &opusenc_class,
744			.priv_data_size = sizeof(OpusEncContext),
745			.init = opus_encode_init,
746			FF_CODEC_ENCODE_CB(opus_encode_frame),
747			.close = opus_encode_end,
748			.caps_internal = FF_CODEC_CAP_INIT_CLEANUP,
749			.p.supported_samplerates = (const int []){ 48000, 0 },
750			.p.ch_layouts = (const AVChannelLayout []){ AV_CHANNEL_LAYOUT_MONO,
751			AV_CHANNEL_LAYOUT_STEREO, { 0 } },
752			.p.sample_fmts = (const enum AVSampleFormat[]){ AV_SAMPLE_FMT_FLTP,
753			AV_SAMPLE_FMT_NONE },
754			};
755