2 * Opus decoder/demuxer common functions
3 * Copyright (c) 2012 Andrew D'Addesio
4 * Copyright (c) 2013-2014 Mozilla Corporation
6 * This file is part of FFmpeg.
8 * FFmpeg is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU Lesser General Public
10 * License as published by the Free Software Foundation; either
11 * version 2.1 of the License, or (at your option) any later version.
13 * FFmpeg is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16 * Lesser General Public License for more details.
18 * You should have received a copy of the GNU Lesser General Public
19 * License along with FFmpeg; if not, write to the Free Software
20 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
23 #ifndef AVCODEC_OPUS_H
24 #define AVCODEC_OPUS_H
28 #include "libavutil/audio_fifo.h"
29 #include "libavutil/float_dsp.h"
30 #include "libavutil/frame.h"
32 #include "libswresample/swresample.h"
37 #define MAX_FRAME_SIZE 1275
39 #define MAX_PACKET_DUR 5760
41 #define CELT_SHORT_BLOCKSIZE 120
42 #define CELT_OVERLAP CELT_SHORT_BLOCKSIZE
43 #define CELT_MAX_LOG_BLOCKS 3
44 #define CELT_MAX_FRAME_SIZE (CELT_SHORT_BLOCKSIZE * (1 << CELT_MAX_LOG_BLOCKS))
45 #define CELT_MAX_BANDS 21
46 #define CELT_VECTORS 11
47 #define CELT_ALLOC_STEPS 6
48 #define CELT_FINE_OFFSET 21
49 #define CELT_MAX_FINE_BITS 8
50 #define CELT_NORM_SCALE 16384
51 #define CELT_QTHETA_OFFSET 4
52 #define CELT_QTHETA_OFFSET_TWOPHASE 16
53 #define CELT_DEEMPH_COEFF 0.85000610f
54 #define CELT_POSTFILTER_MINPERIOD 15
55 #define CELT_ENERGY_SILENCE (-28.0f)
57 #define SILK_HISTORY 322
58 #define SILK_MAX_LPC 16
60 #define ROUND_MULL(a,b,s) (((MUL64(a, b) >> ((s) - 1)) + 1) >> 1)
61 #define ROUND_MUL16(a,b) ((MUL16(a, b) + 16384) >> 15)
63 #define OPUS_TS_HEADER 0x7FE0 // 0x3ff (11 bits)
64 #define OPUS_TS_MASK 0xFFE0 // top 11 bits
66 static const uint8_t opus_default_extradata[30] = {
67 'O', 'p', 'u', 's', 'H', 'e', 'a', 'd',
68 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
69 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
79 OPUS_BANDWIDTH_NARROWBAND,
80 OPUS_BANDWIDTH_MEDIUMBAND,
81 OPUS_BANDWIDTH_WIDEBAND,
82 OPUS_BANDWIDTH_SUPERWIDEBAND,
83 OPUS_BANDWIDTH_FULLBAND
86 typedef struct SilkContext SilkContext;
88 typedef struct CeltContext CeltContext;
90 typedef struct OpusPacket {
91 int packet_size; /**< packet size */
92 int data_size; /**< size of the useful data -- packet size - padding */
93 int code; /**< packet code: specifies the frame layout */
94 int stereo; /**< whether this packet is mono or stereo */
95 int vbr; /**< vbr flag */
96 int config; /**< configuration: tells the audio mode,
97 ** bandwidth, and frame duration */
98 int frame_count; /**< frame count */
99 int frame_offset[MAX_FRAMES]; /**< frame offsets */
100 int frame_size[MAX_FRAMES]; /**< frame sizes */
101 int frame_duration; /**< frame duration, in samples @ 48kHz */
102 enum OpusMode mode; /**< mode */
103 enum OpusBandwidth bandwidth; /**< bandwidth */
106 typedef struct OpusStreamContext {
107 AVCodecContext *avctx;
111 OpusRangeCoder redundancy_rc;
114 AVFloatDSPContext *fdsp;
116 float silk_buf[2][960];
117 float *silk_output[2];
118 DECLARE_ALIGNED(32, float, celt_buf)[2][960];
119 float *celt_output[2];
121 float redundancy_buf[2][960];
122 float *redundancy_output[2];
124 /* data buffers for the final output data */
129 int out_dummy_allocated_size;
132 AVAudioFifo *celt_delay;
134 /* number of samples we still want to get from the resampler */
142 // a mapping between an opus stream and an output channel
143 typedef struct ChannelMap {
147 // when a single decoded channel is mapped to multiple output channels, we
148 // write to the first output directly and copy from it to the others
149 // this field is set to 1 for those copied output channels
151 // this is the index of the output channel to copy from
154 // this channel is silent
158 typedef struct OpusContext {
159 OpusStreamContext *streams;
161 /* current output buffers for each streams */
164 /* Buffers for synchronizing the streams when they have different
165 * resampling delays */
166 AVAudioFifo **sync_buffers;
167 /* number of decoded samples for each stream */
168 int *decoded_samples;
171 int nb_stereo_streams;
173 AVFloatDSPContext *fdsp;
177 ChannelMap *channel_maps;
180 int ff_opus_parse_packet(OpusPacket *pkt, const uint8_t *buf, int buf_size,
183 int ff_opus_parse_extradata(AVCodecContext *avctx, OpusContext *s);
185 int ff_silk_init(AVCodecContext *avctx, SilkContext **ps, int output_channels);
186 void ff_silk_free(SilkContext **ps);
187 void ff_silk_flush(SilkContext *s);
190 * Decode the LP layer of one Opus frame (which may correspond to several SILK
193 int ff_silk_decode_superframe(SilkContext *s, OpusRangeCoder *rc,
195 enum OpusBandwidth bandwidth, int coded_channels,
198 int ff_celt_init(AVCodecContext *avctx, CeltContext **s, int output_channels);
200 void ff_celt_free(CeltContext **s);
202 void ff_celt_flush(CeltContext *s);
204 int ff_celt_decode_frame(CeltContext *s, OpusRangeCoder *rc,
205 float **output, int coded_channels, int frame_size,
206 int startband, int endband);
208 #endif /* AVCODEC_OPUS_H */