diff options
Diffstat (limited to 'libavcodec/opusenc.c')
-rw-r--r-- | libavcodec/opusenc.c | 738 |
1 files changed, 738 insertions, 0 deletions
diff --git a/libavcodec/opusenc.c b/libavcodec/opusenc.c new file mode 100644 index 0000000000..3c08ebcf69 --- /dev/null +++ b/libavcodec/opusenc.c @@ -0,0 +1,738 @@ +/* + * Opus encoder + * Copyright (c) 2017 Rostislav Pehlivanov <atomnuker@gmail.com> + * + * This file is part of FFmpeg. + * + * FFmpeg is free software; you can redistribute it and/or + * modify it under the terms of the GNU Lesser General Public + * License as published by the Free Software Foundation; either + * version 2.1 of the License, or (at your option) any later version. + * + * FFmpeg is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * Lesser General Public License for more details. + * + * You should have received a copy of the GNU Lesser General Public + * License along with FFmpeg; if not, write to the Free Software + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA + */ + +#include "opusenc.h" +#include "opus_pvq.h" +#include "opusenc_psy.h" +#include "opustab.h" + +#include "libavutil/float_dsp.h" +#include "libavutil/opt.h" +#include "internal.h" +#include "bytestream.h" +#include "audio_frame_queue.h" + +typedef struct OpusEncContext { + AVClass *av_class; + OpusEncOptions options; + OpusPsyContext psyctx; + AVCodecContext *avctx; + AudioFrameQueue afq; + AVFloatDSPContext *dsp; + MDCT15Context *mdct[CELT_BLOCK_NB]; + CeltPVQ *pvq; + struct FFBufQueue bufqueue; + + uint8_t enc_id[64]; + int enc_id_bits; + + OpusPacketInfo packet; + + int channels; + + CeltFrame *frame; + OpusRangeCoder *rc; + + /* Actual energy the decoder will have */ + float last_quantized_energy[OPUS_MAX_CHANNELS][CELT_MAX_BANDS]; + + DECLARE_ALIGNED(32, float, scratch)[2048]; +} OpusEncContext; + +static void opus_write_extradata(AVCodecContext *avctx) +{ + uint8_t *bs = avctx->extradata; + + bytestream_put_buffer(&bs, "OpusHead", 8); + bytestream_put_byte (&bs, 0x1); + bytestream_put_byte (&bs, avctx->channels); + bytestream_put_le16 (&bs, avctx->initial_padding); + bytestream_put_le32 (&bs, avctx->sample_rate); + bytestream_put_le16 (&bs, 0x0); + bytestream_put_byte (&bs, 0x0); /* Default layout */ +} + +static int opus_gen_toc(OpusEncContext *s, uint8_t *toc, int *size, int *fsize_needed) +{ + int tmp = 0x0, extended_toc = 0; + static const int toc_cfg[][OPUS_MODE_NB][OPUS_BANDWITH_NB] = { + /* Silk Hybrid Celt Layer */ + /* NB MB WB SWB FB NB MB WB SWB FB NB MB WB SWB FB Bandwidth */ + { { 0, 0, 0, 0, 0 }, { 0, 0, 0, 0, 0 }, { 17, 0, 21, 25, 29 } }, /* 2.5 ms */ + { { 0, 0, 0, 0, 0 }, { 0, 0, 0, 0, 0 }, { 18, 0, 22, 26, 30 } }, /* 5 ms */ + { { 1, 5, 9, 0, 0 }, { 0, 0, 0, 13, 15 }, { 19, 0, 23, 27, 31 } }, /* 10 ms */ + { { 2, 6, 10, 0, 0 }, { 0, 0, 0, 14, 16 }, { 20, 0, 24, 28, 32 } }, /* 20 ms */ + { { 3, 7, 11, 0, 0 }, { 0, 0, 0, 0, 0 }, { 0, 0, 0, 0, 0 } }, /* 40 ms */ + { { 4, 8, 12, 0, 0 }, { 0, 0, 0, 0, 0 }, { 0, 0, 0, 0, 0 } }, /* 60 ms */ + }; + int cfg = toc_cfg[s->packet.framesize][s->packet.mode][s->packet.bandwidth]; + *fsize_needed = 0; + if (!cfg) + return 1; + if (s->packet.frames == 2) { /* 2 packets */ + if (s->frame[0].framebits == s->frame[1].framebits) { /* same size */ + tmp = 0x1; + } else { /* different size */ + tmp = 0x2; + *fsize_needed = 1; /* put frame sizes in the packet */ + } + } else if (s->packet.frames > 2) { + tmp = 0x3; + extended_toc = 1; + } + tmp |= (s->channels > 1) << 2; /* Stereo or mono */ + tmp |= (cfg - 1) << 3; /* codec configuration */ + *toc++ = tmp; + if (extended_toc) { + for (int i = 0; i < (s->packet.frames - 1); i++) + *fsize_needed |= (s->frame[i].framebits != s->frame[i + 1].framebits); + tmp = (*fsize_needed) << 7; /* vbr flag */ + tmp |= (0) << 6; /* padding flag */ + tmp |= s->packet.frames; + *toc++ = tmp; + } + *size = 1 + extended_toc; + return 0; +} + +static void celt_frame_setup_input(OpusEncContext *s, CeltFrame *f) +{ + AVFrame *cur = NULL; + const int subframesize = s->avctx->frame_size; + int subframes = OPUS_BLOCK_SIZE(s->packet.framesize) / subframesize; + + cur = ff_bufqueue_get(&s->bufqueue); + + for (int ch = 0; ch < f->channels; ch++) { + CeltBlock *b = &f->block[ch]; + const void *input = cur->extended_data[ch]; + size_t bps = av_get_bytes_per_sample(cur->format); + memcpy(b->overlap, input, bps*cur->nb_samples); + } + + av_frame_free(&cur); + + for (int sf = 0; sf < subframes; sf++) { + if (sf != (subframes - 1)) + cur = ff_bufqueue_get(&s->bufqueue); + else + cur = ff_bufqueue_peek(&s->bufqueue, 0); + + for (int ch = 0; ch < f->channels; ch++) { + CeltBlock *b = &f->block[ch]; + const void *input = cur->extended_data[ch]; + const size_t bps = av_get_bytes_per_sample(cur->format); + const size_t left = (subframesize - cur->nb_samples)*bps; + const size_t len = FFMIN(subframesize, cur->nb_samples)*bps; + memcpy(&b->samples[sf*subframesize], input, len); + memset(&b->samples[cur->nb_samples], 0, left); + } + + /* Last frame isn't popped off and freed yet - we need it for overlap */ + if (sf != (subframes - 1)) + av_frame_free(&cur); + } +} + +/* Apply the pre emphasis filter */ +static void celt_apply_preemph_filter(OpusEncContext *s, CeltFrame *f) +{ + const int subframesize = s->avctx->frame_size; + const int subframes = OPUS_BLOCK_SIZE(s->packet.framesize) / subframesize; + + /* Filter overlap */ + for (int ch = 0; ch < f->channels; ch++) { + CeltBlock *b = &f->block[ch]; + float m = b->emph_coeff; + for (int i = 0; i < CELT_OVERLAP; i++) { + float sample = b->overlap[i]; + b->overlap[i] = sample - m; + m = sample * CELT_EMPH_COEFF; + } + b->emph_coeff = m; + } + + /* Filter the samples but do not update the last subframe's coeff - overlap ^^^ */ + for (int sf = 0; sf < subframes; sf++) { + for (int ch = 0; ch < f->channels; ch++) { + CeltBlock *b = &f->block[ch]; + float m = b->emph_coeff; + for (int i = 0; i < subframesize; i++) { + float sample = b->samples[sf*subframesize + i]; + b->samples[sf*subframesize + i] = sample - m; + m = sample * CELT_EMPH_COEFF; + } + if (sf != (subframes - 1)) + b->emph_coeff = m; + } + } +} + +/* Create the window and do the mdct */ +static void celt_frame_mdct(OpusEncContext *s, CeltFrame *f) +{ + float *win = s->scratch, *temp = s->scratch + 1920; + + if (f->transient) { + for (int ch = 0; ch < f->channels; ch++) { + CeltBlock *b = &f->block[ch]; + float *src1 = b->overlap; + for (int t = 0; t < f->blocks; t++) { + float *src2 = &b->samples[CELT_OVERLAP*t]; + s->dsp->vector_fmul(win, src1, ff_celt_window, 128); + s->dsp->vector_fmul_reverse(&win[CELT_OVERLAP], src2, + ff_celt_window - 8, 128); + src1 = src2; + s->mdct[0]->mdct(s->mdct[0], b->coeffs + t, win, f->blocks); + } + } + } else { + int blk_len = OPUS_BLOCK_SIZE(f->size), wlen = OPUS_BLOCK_SIZE(f->size + 1); + int rwin = blk_len - CELT_OVERLAP, lap_dst = (wlen - blk_len - CELT_OVERLAP) >> 1; + memset(win, 0, wlen*sizeof(float)); + for (int ch = 0; ch < f->channels; ch++) { + CeltBlock *b = &f->block[ch]; + + /* Overlap */ + s->dsp->vector_fmul(temp, b->overlap, ff_celt_window, 128); + memcpy(win + lap_dst, temp, CELT_OVERLAP*sizeof(float)); + + /* Samples, flat top window */ + memcpy(&win[lap_dst + CELT_OVERLAP], b->samples, rwin*sizeof(float)); + + /* Samples, windowed */ + s->dsp->vector_fmul_reverse(temp, b->samples + rwin, + ff_celt_window - 8, 128); + memcpy(win + lap_dst + blk_len, temp, CELT_OVERLAP*sizeof(float)); + + s->mdct[f->size]->mdct(s->mdct[f->size], b->coeffs, win, 1); + } + } + + for (int ch = 0; ch < f->channels; ch++) { + CeltBlock *block = &f->block[ch]; + for (int i = 0; i < CELT_MAX_BANDS; i++) { + float ener = 0.0f; + int band_offset = ff_celt_freq_bands[i] << f->size; + int band_size = ff_celt_freq_range[i] << f->size; + float *coeffs = &block->coeffs[band_offset]; + + for (int j = 0; j < band_size; j++) + ener += coeffs[j]*coeffs[j]; + + block->lin_energy[i] = sqrtf(ener) + FLT_EPSILON; + ener = 1.0f/block->lin_energy[i]; + + for (int j = 0; j < band_size; j++) + coeffs[j] *= ener; + + block->energy[i] = log2f(block->lin_energy[i]) - ff_celt_mean_energy[i]; + + /* CELT_ENERGY_SILENCE is what the decoder uses and its not -infinity */ + block->energy[i] = FFMAX(block->energy[i], CELT_ENERGY_SILENCE); + } + } +} + +static void celt_enc_tf(CeltFrame *f, OpusRangeCoder *rc) +{ + int tf_select = 0, diff = 0, tf_changed = 0, tf_select_needed; + int bits = f->transient ? 2 : 4; + + tf_select_needed = ((f->size && (opus_rc_tell(rc) + bits + 1) <= f->framebits)); + + for (int i = f->start_band; i < f->end_band; i++) { + if ((opus_rc_tell(rc) + bits + tf_select_needed) <= f->framebits) { + const int tbit = (diff ^ 1) == f->tf_change[i]; + ff_opus_rc_enc_log(rc, tbit, bits); + diff ^= tbit; + tf_changed |= diff; + } + bits = f->transient ? 4 : 5; + } + + if (tf_select_needed && ff_celt_tf_select[f->size][f->transient][0][tf_changed] != + ff_celt_tf_select[f->size][f->transient][1][tf_changed]) { + ff_opus_rc_enc_log(rc, f->tf_select, 1); + tf_select = f->tf_select; + } + + for (int i = f->start_band; i < f->end_band; i++) + f->tf_change[i] = ff_celt_tf_select[f->size][f->transient][tf_select][f->tf_change[i]]; +} + +static void celt_enc_quant_pfilter(OpusRangeCoder *rc, CeltFrame *f) +{ + float gain = f->pf_gain; + int txval, octave = f->pf_octave, period = f->pf_period, tapset = f->pf_tapset; + + ff_opus_rc_enc_log(rc, f->pfilter, 1); + if (!f->pfilter) + return; + + /* Octave */ + txval = FFMIN(octave, 6); + ff_opus_rc_enc_uint(rc, txval, 6); + octave = txval; + /* Period */ + txval = av_clip(period - (16 << octave) + 1, 0, (1 << (4 + octave)) - 1); + ff_opus_rc_put_raw(rc, period, 4 + octave); + period = txval + (16 << octave) - 1; + /* Gain */ + txval = FFMIN(((int)(gain / 0.09375f)) - 1, 7); + ff_opus_rc_put_raw(rc, txval, 3); + gain = 0.09375f * (txval + 1); + /* Tapset */ + if ((opus_rc_tell(rc) + 2) <= f->framebits) + ff_opus_rc_enc_cdf(rc, tapset, ff_celt_model_tapset); + else + tapset = 0; + /* Finally create the coeffs */ + for (int i = 0; i < 2; i++) { + CeltBlock *block = &f->block[i]; + + block->pf_period_new = FFMAX(period, CELT_POSTFILTER_MINPERIOD); + block->pf_gains_new[0] = gain * ff_celt_postfilter_taps[tapset][0]; + block->pf_gains_new[1] = gain * ff_celt_postfilter_taps[tapset][1]; + block->pf_gains_new[2] = gain * ff_celt_postfilter_taps[tapset][2]; + } +} + +static void exp_quant_coarse(OpusRangeCoder *rc, CeltFrame *f, + float last_energy[][CELT_MAX_BANDS], int intra) +{ + float alpha, beta, prev[2] = { 0, 0 }; + const uint8_t *pmod = ff_celt_coarse_energy_dist[f->size][intra]; + + /* Inter is really just differential coding */ + if (opus_rc_tell(rc) + 3 <= f->framebits) + ff_opus_rc_enc_log(rc, intra, 3); + else + intra = 0; + + if (intra) { + alpha = 0.0f; + beta = 1.0f - (4915.0f/32768.0f); + } else { + alpha = ff_celt_alpha_coef[f->size]; + beta = ff_celt_beta_coef[f->size]; + } + + for (int i = f->start_band; i < f->end_band; i++) { + for (int ch = 0; ch < f->channels; ch++) { + CeltBlock *block = &f->block[ch]; + const int left = f->framebits - opus_rc_tell(rc); + const float last = FFMAX(-9.0f, last_energy[ch][i]); + float diff = block->energy[i] - prev[ch] - last*alpha; + int q_en = lrintf(diff); + if (left >= 15) { + ff_opus_rc_enc_laplace(rc, &q_en, pmod[i << 1] << 7, pmod[(i << 1) + 1] << 6); + } else if (left >= 2) { + q_en = av_clip(q_en, -1, 1); + ff_opus_rc_enc_cdf(rc, 2*q_en + 3*(q_en < 0), ff_celt_model_energy_small); + } else if (left >= 1) { + q_en = av_clip(q_en, -1, 0); + ff_opus_rc_enc_log(rc, (q_en & 1), 1); + } else q_en = -1; + + block->error_energy[i] = q_en - diff; + prev[ch] += beta * q_en; + } + } +} + +static void celt_quant_coarse(CeltFrame *f, OpusRangeCoder *rc, + float last_energy[][CELT_MAX_BANDS]) +{ + uint32_t inter, intra; + OPUS_RC_CHECKPOINT_SPAWN(rc); + + exp_quant_coarse(rc, f, last_energy, 1); + intra = OPUS_RC_CHECKPOINT_BITS(rc); + + OPUS_RC_CHECKPOINT_ROLLBACK(rc); + + exp_quant_coarse(rc, f, last_energy, 0); + inter = OPUS_RC_CHECKPOINT_BITS(rc); + + if (inter > intra) { /* Unlikely */ + OPUS_RC_CHECKPOINT_ROLLBACK(rc); + exp_quant_coarse(rc, f, last_energy, 1); + } +} + +static void celt_quant_fine(CeltFrame *f, OpusRangeCoder *rc) +{ + for (int i = f->start_band; i < f->end_band; i++) { + if (!f->fine_bits[i]) + continue; + for (int ch = 0; ch < f->channels; ch++) { + CeltBlock *block = &f->block[ch]; + int quant, lim = (1 << f->fine_bits[i]); + float offset, diff = 0.5f - block->error_energy[i]; + quant = av_clip(floor(diff*lim), 0, lim - 1); + ff_opus_rc_put_raw(rc, quant, f->fine_bits[i]); + offset = 0.5f - ((quant + 0.5f) * (1 << (14 - f->fine_bits[i])) / 16384.0f); + block->error_energy[i] -= offset; + } + } +} + +static void celt_quant_final(OpusEncContext *s, OpusRangeCoder *rc, CeltFrame *f) +{ + for (int priority = 0; priority < 2; priority++) { + for (int i = f->start_band; i < f->end_band && (f->framebits - opus_rc_tell(rc)) >= f->channels; i++) { + if (f->fine_priority[i] != priority || f->fine_bits[i] >= CELT_MAX_FINE_BITS) + continue; + for (int ch = 0; ch < f->channels; ch++) { + CeltBlock *block = &f->block[ch]; + const float err = block->error_energy[i]; + const float offset = 0.5f * (1 << (14 - f->fine_bits[i] - 1)) / 16384.0f; + const int sign = FFABS(err + offset) < FFABS(err - offset); + ff_opus_rc_put_raw(rc, sign, 1); + block->error_energy[i] -= offset*(1 - 2*sign); + } + } + } +} + +static void celt_encode_frame(OpusEncContext *s, OpusRangeCoder *rc, + CeltFrame *f, int index) +{ + ff_opus_rc_enc_init(rc); + + ff_opus_psy_celt_frame_init(&s->psyctx, f, index); + + celt_frame_setup_input(s, f); + + if (f->silence) { + if (f->framebits >= 16) + ff_opus_rc_enc_log(rc, 1, 15); /* Silence (if using explicit singalling) */ + for (int ch = 0; ch < s->channels; ch++) + memset(s->last_quantized_energy[ch], 0.0f, sizeof(float)*CELT_MAX_BANDS); + return; + } + + /* Filters */ + celt_apply_preemph_filter(s, f); + if (f->pfilter) { + ff_opus_rc_enc_log(rc, 0, 15); + celt_enc_quant_pfilter(rc, f); + } + + /* Transform */ + celt_frame_mdct(s, f); + + /* Need to handle transient/non-transient switches at any point during analysis */ + while (ff_opus_psy_celt_frame_process(&s->psyctx, f, index)) + celt_frame_mdct(s, f); + + ff_opus_rc_enc_init(rc); + + /* Silence */ + ff_opus_rc_enc_log(rc, 0, 15); + + /* Pitch filter */ + if (!f->start_band && opus_rc_tell(rc) + 16 <= f->framebits) + celt_enc_quant_pfilter(rc, f); + + /* Transient flag */ + if (f->size && opus_rc_tell(rc) + 3 <= f->framebits) + ff_opus_rc_enc_log(rc, f->transient, 3); + + /* Main encoding */ + celt_quant_coarse (f, rc, s->last_quantized_energy); + celt_enc_tf (f, rc); + ff_celt_bitalloc (f, rc, 1); + celt_quant_fine (f, rc); + ff_celt_quant_bands(f, rc); + + /* Anticollapse bit */ + if (f->anticollapse_needed) + ff_opus_rc_put_raw(rc, f->anticollapse, 1); + + /* Final per-band energy adjustments from leftover bits */ + celt_quant_final(s, rc, f); + + for (int ch = 0; ch < f->channels; ch++) { + CeltBlock *block = &f->block[ch]; + for (int i = 0; i < CELT_MAX_BANDS; i++) + s->last_quantized_energy[ch][i] = block->energy[i] + block->error_energy[i]; + } +} + +static inline int write_opuslacing(uint8_t *dst, int v) +{ + dst[0] = FFMIN(v - FFALIGN(v - 255, 4), v); + dst[1] = v - dst[0] >> 2; + return 1 + (v >= 252); +} + +static void opus_packet_assembler(OpusEncContext *s, AVPacket *avpkt) +{ + int offset, fsize_needed; + + /* Write toc */ + opus_gen_toc(s, avpkt->data, &offset, &fsize_needed); + + /* Frame sizes if needed */ + if (fsize_needed) { + for (int i = 0; i < s->packet.frames - 1; i++) { + offset += write_opuslacing(avpkt->data + offset, + s->frame[i].framebits >> 3); + } + } + + /* Packets */ + for (int i = 0; i < s->packet.frames; i++) { + ff_opus_rc_enc_end(&s->rc[i], avpkt->data + offset, + s->frame[i].framebits >> 3); + offset += s->frame[i].framebits >> 3; + } + + avpkt->size = offset; +} + +/* Used as overlap for the first frame and padding for the last encoded packet */ +static AVFrame *spawn_empty_frame(OpusEncContext *s) +{ + AVFrame *f = av_frame_alloc(); + if (!f) + return NULL; + f->format = s->avctx->sample_fmt; + f->nb_samples = s->avctx->frame_size; + f->channel_layout = s->avctx->channel_layout; + if (av_frame_get_buffer(f, 4)) { + av_frame_free(&f); + return NULL; + } + for (int i = 0; i < s->channels; i++) { + size_t bps = av_get_bytes_per_sample(f->format); + memset(f->extended_data[i], 0, bps*f->nb_samples); + } + return f; +} + +static int opus_encode_frame(AVCodecContext *avctx, AVPacket *avpkt, + const AVFrame *frame, int *got_packet_ptr) +{ + OpusEncContext *s = avctx->priv_data; + int ret, frame_size, alloc_size = 0; + + if (frame) { /* Add new frame to queue */ + if ((ret = ff_af_queue_add(&s->afq, frame)) < 0) + return ret; + ff_bufqueue_add(avctx, &s->bufqueue, av_frame_clone(frame)); + } else { + ff_opus_psy_signal_eof(&s->psyctx); + if (!s->afq.remaining_samples || !avctx->frame_number) + return 0; /* We've been flushed and there's nothing left to encode */ + } + + /* Run the psychoacoustic system */ + if (ff_opus_psy_process(&s->psyctx, &s->packet)) + return 0; + + frame_size = OPUS_BLOCK_SIZE(s->packet.framesize); + + if (!frame) { + /* This can go negative, that's not a problem, we only pad if positive */ + int pad_empty = s->packet.frames*(frame_size/s->avctx->frame_size) - s->bufqueue.available + 1; + /* Pad with empty 2.5 ms frames to whatever framesize was decided, + * this should only happen at the very last flush frame. The frames + * allocated here will be freed (because they have no other references) + * after they get used by celt_frame_setup_input() */ + for (int i = 0; i < pad_empty; i++) { + AVFrame *empty = spawn_empty_frame(s); + if (!empty) + return AVERROR(ENOMEM); + ff_bufqueue_add(avctx, &s->bufqueue, empty); + } + } + + for (int i = 0; i < s->packet.frames; i++) { + celt_encode_frame(s, &s->rc[i], &s->frame[i], i); + alloc_size += s->frame[i].framebits >> 3; + } + + /* Worst case toc + the frame lengths if needed */ + alloc_size += 2 + s->packet.frames*2; + + if ((ret = ff_alloc_packet2(avctx, avpkt, alloc_size, 0)) < 0) + return ret; + + /* Assemble packet */ + opus_packet_assembler(s, avpkt); + + /* Update the psychoacoustic system */ + ff_opus_psy_postencode_update(&s->psyctx, s->frame, s->rc); + + /* Remove samples from queue and skip if needed */ + ff_af_queue_remove(&s->afq, s->packet.frames*frame_size, &avpkt->pts, &avpkt->duration); + if (s->packet.frames*frame_size > avpkt->duration) { + uint8_t *side = av_packet_new_side_data(avpkt, AV_PKT_DATA_SKIP_SAMPLES, 10); + if (!side) + return AVERROR(ENOMEM); + AV_WL32(&side[4], s->packet.frames*frame_size - avpkt->duration + 120); + } + + *got_packet_ptr = 1; + + return 0; +} + +static av_cold int opus_encode_end(AVCodecContext *avctx) +{ + OpusEncContext *s = avctx->priv_data; + + for (int i = 0; i < CELT_BLOCK_NB; i++) + ff_mdct15_uninit(&s->mdct[i]); + + ff_celt_pvq_uninit(&s->pvq); + av_freep(&s->dsp); + av_freep(&s->frame); + av_freep(&s->rc); + ff_af_queue_close(&s->afq); + ff_opus_psy_end(&s->psyctx); + ff_bufqueue_discard_all(&s->bufqueue); + av_freep(&avctx->extradata); + + return 0; +} + +static av_cold int opus_encode_init(AVCodecContext *avctx) +{ + int ret, max_frames; + OpusEncContext *s = avctx->priv_data; + + s->avctx = avctx; + s->channels = avctx->channels; + + /* Opus allows us to change the framesize on each packet (and each packet may + * have multiple frames in it) but we can't change the codec's frame size on + * runtime, so fix it to the lowest possible number of samples and use a queue + * to accumulate AVFrames until we have enough to encode whatever the encoder + * decides is the best */ + avctx->frame_size = 120; + /* Initial padding will change if SILK is ever supported */ + avctx->initial_padding = 120; + + if (!avctx->bit_rate) { + int coupled = ff_opus_default_coupled_streams[s->channels - 1]; + avctx->bit_rate = coupled*(96000) + (s->channels - coupled*2)*(48000); + } else if (avctx->bit_rate < 6000 || avctx->bit_rate > 255000 * s->channels) { + int64_t clipped_rate = av_clip(avctx->bit_rate, 6000, 255000 * s->channels); + av_log(avctx, AV_LOG_ERROR, "Unsupported bitrate %"PRId64" kbps, clipping to %"PRId64" kbps\n", + avctx->bit_rate/1000, clipped_rate/1000); + avctx->bit_rate = clipped_rate; + } + + /* Extradata */ + avctx->extradata_size = 19; + avctx->extradata = av_malloc(avctx->extradata_size + AV_INPUT_BUFFER_PADDING_SIZE); + if (!avctx->extradata) + return AVERROR(ENOMEM); + opus_write_extradata(avctx); + + ff_af_queue_init(avctx, &s->afq); + + if ((ret = ff_celt_pvq_init(&s->pvq, 1)) < 0) + return ret; + + if (!(s->dsp = avpriv_float_dsp_alloc(avctx->flags & AV_CODEC_FLAG_BITEXACT))) + return AVERROR(ENOMEM); + + /* I have no idea why a base scaling factor of 68 works, could be the twiddles */ + for (int i = 0; i < CELT_BLOCK_NB; i++) + if ((ret = ff_mdct15_init(&s->mdct[i], 0, i + 3, 68 << (CELT_BLOCK_NB - 1 - i)))) + return AVERROR(ENOMEM); + + /* Zero out previous energy (matters for inter first frame) */ + for (int ch = 0; ch < s->channels; ch++) + memset(s->last_quantized_energy[ch], 0.0f, sizeof(float)*CELT_MAX_BANDS); + + /* Allocate an empty frame to use as overlap for the first frame of audio */ + ff_bufqueue_add(avctx, &s->bufqueue, spawn_empty_frame(s)); + if (!ff_bufqueue_peek(&s->bufqueue, 0)) + return AVERROR(ENOMEM); + + if ((ret = ff_opus_psy_init(&s->psyctx, s->avctx, &s->bufqueue, &s->options))) + return ret; + + /* Frame structs and range coder buffers */ + max_frames = ceilf(FFMIN(s->options.max_delay_ms, 120.0f)/2.5f); + s->frame = av_malloc(max_frames*sizeof(CeltFrame)); + if (!s->frame) + return AVERROR(ENOMEM); + s->rc = av_malloc(max_frames*sizeof(OpusRangeCoder)); + if (!s->rc) + return AVERROR(ENOMEM); + + for (int i = 0; i < max_frames; i++) { + s->frame[i].dsp = s->dsp; + s->frame[i].avctx = s->avctx; + s->frame[i].seed = 0; + s->frame[i].pvq = s->pvq; + s->frame[i].apply_phase_inv = 1; + s->frame[i].block[0].emph_coeff = s->frame[i].block[1].emph_coeff = 0.0f; + } + + return 0; +} + +#define OPUSENC_FLAGS AV_OPT_FLAG_ENCODING_PARAM | AV_OPT_FLAG_AUDIO_PARAM +static const AVOption opusenc_options[] = { + { "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" }, + { NULL }, +}; + +static const AVClass opusenc_class = { + .class_name = "Opus encoder", + .item_name = av_default_item_name, + .option = opusenc_options, + .version = LIBAVUTIL_VERSION_INT, +}; + +static const AVCodecDefault opusenc_defaults[] = { + { "b", "0" }, + { "compression_level", "10" }, + { NULL }, +}; + +AVCodec ff_opus_encoder = { + .name = "opus", + .long_name = NULL_IF_CONFIG_SMALL("Opus"), + .type = AVMEDIA_TYPE_AUDIO, + .id = AV_CODEC_ID_OPUS, + .defaults = opusenc_defaults, + .priv_class = &opusenc_class, + .priv_data_size = sizeof(OpusEncContext), + .init = opus_encode_init, + .encode2 = opus_encode_frame, + .close = opus_encode_end, + .caps_internal = FF_CODEC_CAP_INIT_THREADSAFE | FF_CODEC_CAP_INIT_CLEANUP, + .capabilities = AV_CODEC_CAP_EXPERIMENTAL | AV_CODEC_CAP_SMALL_LAST_FRAME | AV_CODEC_CAP_DELAY, + .supported_samplerates = (const int []){ 48000, 0 }, + .channel_layouts = (const uint64_t []){ AV_CH_LAYOUT_MONO, + AV_CH_LAYOUT_STEREO, 0 }, + .sample_fmts = (const enum AVSampleFormat[]){ AV_SAMPLE_FMT_FLTP, + AV_SAMPLE_FMT_NONE }, +}; 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