1 /* 2 * Copyright (C) 2018 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 /* 18 * The Opus specification is part of IETF RFC 6716: 19 * http://tools.ietf.org/html/rfc6716 20 */ 21 22 #ifndef OPUS_HEADER_H_ 23 #define OPUS_HEADER_H_ 24 25 namespace android { 26 27 /* Constants used for delimiting Opus CSD */ 28 #define AOPUS_CSD_MARKER_PREFIX "AOPUS" 29 #define AOPUS_CSD_MARKER_PREFIX_SIZE (sizeof(AOPUS_CSD_MARKER_PREFIX) - 1) 30 #define AOPUS_CSD_OPUS_HEADER_MARKER AOPUS_CSD_MARKER_PREFIX "HDR" 31 #define AOPUS_CSD_CODEC_DELAY_MARKER AOPUS_CSD_MARKER_PREFIX "DLY" 32 #define AOPUS_CSD_SEEK_PREROLL_MARKER AOPUS_CSD_MARKER_PREFIX "PRL" 33 #define AOPUS_MARKER_SIZE 8 34 #define AOPUS_LENGTH_SIZE sizeof(uint64_t) 35 #define AOPUS_CSD_CODEC_DELAY_SIZE \ 36 (AOPUS_MARKER_SIZE) + (AOPUS_LENGTH_SIZE) + sizeof(uint64_t) 37 #define AOPUS_CSD_SEEK_PREROLL_SIZE \ 38 (AOPUS_MARKER_SIZE) + (AOPUS_LENGTH_SIZE) + sizeof(uint64_t) 39 40 /* OpusHead csd minimum size is 19 */ 41 #define AOPUS_OPUSHEAD_MINSIZE 19 42 #define AOPUS_CSD_OPUSHEAD_MINSIZE \ 43 (AOPUS_MARKER_SIZE) + (AOPUS_LENGTH_SIZE) + (AOPUS_OPUSHEAD_MINSIZE) 44 45 #define AOPUS_UNIFIED_CSD_MINSIZE \ 46 ((AOPUS_CSD_OPUSHEAD_MINSIZE) + \ 47 (AOPUS_CSD_CODEC_DELAY_SIZE) + \ 48 (AOPUS_CSD_SEEK_PREROLL_SIZE)) 49 50 /* OpusHead csd at max can be AOPUS_CSD_OPUSHEAD_MINSIZE + 2 + max number of channels (255) */ 51 #define AOPUS_OPUSHEAD_MAXSIZE ((AOPUS_OPUSHEAD_MINSIZE) + 2 + 255) 52 #define AOPUS_CSD_OPUSHEAD_MAXSIZE \ 53 (AOPUS_MARKER_SIZE) + (AOPUS_LENGTH_SIZE) + (AOPUS_OPUSHEAD_MAXSIZE) 54 55 #define AOPUS_UNIFIED_CSD_MAXSIZE \ 56 ((AOPUS_CSD_OPUSHEAD_MAXSIZE) + \ 57 (AOPUS_CSD_CODEC_DELAY_SIZE) + \ 58 (AOPUS_CSD_SEEK_PREROLL_SIZE)) 59 60 struct OpusHeader { 61 int channels; 62 int channel_mapping; 63 int num_streams; 64 int num_coupled; 65 int16_t gain_db; 66 int skip_samples; 67 uint8_t stream_map[8]; 68 }; 69 70 bool ParseOpusHeader(const uint8_t* data, size_t data_size, OpusHeader* header); 71 int WriteOpusHeader(const OpusHeader &header, int input_sample_rate, uint8_t* output, size_t output_size); 72 bool GetOpusHeaderBuffers(const uint8_t *data, size_t data_size, 73 void **opusHeadBuf, size_t *opusHeadSize, 74 void **codecDelayBuf, size_t *codecDelaySize, 75 void **seekPreRollBuf, size_t *seekPreRollSize); 76 int WriteOpusHeaders(const OpusHeader &header, int inputSampleRate, 77 uint8_t* output, size_t outputSize, uint64_t codecDelay, 78 uint64_t seekPreRoll); 79 bool IsOpusHeader(const uint8_t *data, size_t data_size); 80 } // namespace android 81 82 #endif // OPUS_HEADER_H_ 83