/***************************************************************************** * aac.h: ISO/IEC 14496-3 Advanced Audio Coding ***************************************************************************** * Copyright (C) 2010, 2013, 2017 VideoLAN * * Authors: Christophe Massiot * * Permission is hereby granted, free of charge, to any person obtaining * a copy of this software and associated documentation files (the * "Software"), to deal in the Software without restriction, including * without limitation the rights to use, copy, modify, merge, publish, * distribute, sublicense, and/or sell copies of the Software, and to * permit persons to whom the Software is furnished to do so, subject * to the following conditions: * * The above copyright notice and this permission notice shall be * included in all copies or substantial portions of the Software. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. * IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY * CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. *****************************************************************************/ /* * Normative references: * - ISO/IEC 14496-3 Subpart 4:1998(E) * (Advanced Audio Coding, Time/Frequency Coding) * - ISO/IEC 13818-1:2013(E) (MPEG-2 Systems) */ #ifndef __BITSTREAM_MPEG_AAC_H__ #define __BITSTREAM_MPEG_AAC_H__ #include /* uint8_t, uint16_t, etc... */ #include /* bool */ #ifdef __cplusplus extern "C" { #endif /***************************************************************************** * ADTS header *****************************************************************************/ #define ADTS_HEADER_SIZE 7 #define ADTS_CRC_SIZE 2 #define ADTS_SAMPLES_PER_BLOCK 1024 #define ADTS_PROFILE_MAIN 0 #define ADTS_PROFILE_LC 1 #define ADTS_PROFILE_SSR 2 /* fixed header */ static inline void adts_set_sync(uint8_t *p_adts) { p_adts[0] = 0xff; p_adts[1] = 0xf9; /* protection absent */ p_adts[2] = 0x0; p_adts[3] = 0x0; p_adts[4] = 0x0; p_adts[5] = 0x0; p_adts[6] = 0x0; } static inline bool adts_get_protection_absent(const uint8_t *p_adts) { return !!(p_adts[1] & 0x01); } static inline void adts_clear_protection_absent(uint8_t *p_adts) { p_adts[1] &= ~0x01; } static inline uint8_t adts_get_profile(const uint8_t *p_adts) { return p_adts[2] >> 6; } static inline void adts_set_profile(uint8_t *p_adts, uint8_t i_profile) { p_adts[2] &= ~0xc0; p_adts[2] |= i_profile << 6; } static inline uint8_t adts_get_sampling_freq(const uint8_t *p_adts) { return (p_adts[2] & 0x3c) >> 2; } static inline void adts_set_sampling_freq(uint8_t *p_adts, uint8_t i_freq) { p_adts[2] &= ~0x3c; p_adts[2] |= (i_freq & 0xf) << 2; } static inline uint8_t adts_get_channels(const uint8_t *p_adts) { return ((p_adts[2] & 0x01) << 2) | (p_adts[3] >> 6); } static inline void adts_set_channels(uint8_t *p_adts, uint8_t i_channels) { p_adts[2] &= ~0x03; /* also clear out the private bit */ p_adts[2] |= (i_channels & 0x7) >> 2; p_adts[3] &= ~0xc0; p_adts[3] |= (i_channels & 0x7) << 6; } static inline bool adts_get_copy(const uint8_t *p_adts) { return !!(p_adts[3] & 0x20); } static inline void adts_set_copy(uint8_t *p_adts) { p_adts[3] |= 0x20; } static inline bool adts_get_home(const uint8_t *p_adts) { return !!(p_adts[3] & 0x10); } static inline void adts_set_home(uint8_t *p_adts) { p_adts[3] |= 0x10; } /* variable header */ static inline void adts_get_cp_id(const uint8_t *p_adts, bool *pb_bit, bool *pb_start) { *pb_bit = !!(p_adts[3] & 0x08); *pb_start = !!(p_adts[3] & 0x04); } static inline void adts_set_cp_id(uint8_t *p_adts, bool b_bit, bool b_start) { p_adts[3] &= ~0x0c; if (b_bit) p_adts[3] |= 0x08; if (b_start) p_adts[3] |= 0x04; } static inline uint16_t adts_get_length(const uint8_t *p_adts) { return ((p_adts[3] & 0x03) << 11) | (p_adts[4] << 3) | (p_adts[5] >> 5); } static inline void adts_set_length(uint8_t *p_adts, uint16_t i_length) { p_adts[3] &= ~0x03; p_adts[3] |= (i_length >> 11) & 0x03; p_adts[4] = i_length >> 3; p_adts[5] &= ~0xe0; p_adts[5] |= (i_length << 5) & 0xe0; } static inline uint16_t adts_get_fullness(const uint8_t *p_adts) { return ((p_adts[5] & 0x1f) << 6) | (p_adts[6] >> 2); } static inline void adts_set_fullness(uint8_t *p_adts, uint16_t i_fullness) { p_adts[5] &= ~0x1f; p_adts[5] |= (i_fullness >> 6) & 0x1f; p_adts[6] &= ~0xfc; p_adts[6] |= (i_fullness << 2) & 0xfc; } /* blocks == number of blocks - 1 */ static inline uint8_t adts_get_num_blocks(const uint8_t *p_adts) { return (p_adts[6] & 0x03); } static inline void adts_set_num_blocks(uint8_t *p_adts, uint8_t i_blocks_min1) { p_adts[6] &= ~0x03; p_adts[6] |= i_blocks_min1 & 0x03; } static inline bool adts_sync_compare(const uint8_t *p_adts1, const uint8_t *p_adts2) { return p_adts1[0] == p_adts2[0] && p_adts1[1] == p_adts2[1] && p_adts1[2] == p_adts2[2] && (p_adts1[3] & 0xfc) == (p_adts2[3] & 0xfc); } /* same but only takes into account meaningful fields */ static inline bool adts_sync_compare_formats(const uint8_t *p_adts1, const uint8_t *p_adts2) { return p_adts1[0] == p_adts2[0] && (p_adts1[1] & 0xfe) == (p_adts2[1] & 0xfe) && p_adts1[2] == p_adts2[2] && (p_adts1[3] & 0xc0) == (p_adts2[3] & 0xc0); } /***************************************************************************** * LOAS header *****************************************************************************/ #define LOAS_HEADER_SIZE 3 static inline void loas_set_sync(uint8_t *p) { p[0] = 0x56; p[1] = 0xe0; p[2] = 0x0; } static inline uint16_t loas_get_length(const uint8_t *p) { return ((p[1] & 0x01f) << 8) | p[2]; } static inline void loas_set_length(uint8_t *p, uint16_t val) { p[1] = 0xe0 | (val >> 8); p[2] = val & 0xff; } /***************************************************************************** * AudioSpecificConfig *****************************************************************************/ #define ASC_TYPE_MAIN 1 #define ASC_TYPE_LC 2 #define ASC_TYPE_SSR 3 #define ASC_TYPE_LTP 4 #define ASC_TYPE_SBR 5 #define ASC_TYPE_SCALABLE 6 #define ASC_TYPE_TWINVQ 7 #define ASC_TYPE_CELP 8 #define ASC_TYPE_HVXC 9 #define ASC_TYPE_ER_LC 17 #define ASC_TYPE_ER_LTP 19 #define ASC_TYPE_ER_SCALABLE 20 #define ASC_TYPE_ER_TWINVQ 21 #define ASC_TYPE_ER_BSAC 22 #define ASC_TYPE_ER_LD 23 #define ASC_TYPE_PS 29 #define ASC_FLT_VARIABLE 0 #define ASC_FLT_FIXED 1 #define ASC_FLT_CELP_2 3 #define ASC_FLT_CELP_FIXED 4 #define ASC_FLT_CELP_4 5 #define ASC_FLT_HVXC_FIXED 6 #define ASC_FLT_HVXC_4 7 /* Returns the profile_and_level structure for MPEG-4 audio descriptor */ static inline uint8_t asc_get_profilelevel(uint8_t asc_aot, uint8_t channels, uint32_t rate) { uint8_t profilelevel; switch (asc_aot) { case ASC_TYPE_LC: profilelevel = 0x50; break; case ASC_TYPE_SBR: profilelevel = 0x58; break; case ASC_TYPE_ER_LD: return 0x38; case ASC_TYPE_PS: profilelevel = 0x60; break; default: return 0xf; } if (rate > 48000) return profilelevel + 3; if (channels > 2) return profilelevel + 2; if (rate > 24000) return profilelevel + 1; return profilelevel; } /***************************************************************************** * AAC syntactic elements *****************************************************************************/ #define AAC_SYN_SCE 0 #define AAC_SYN_CPE 1 #define AAC_SYN_CCE 2 #define AAC_SYN_LFE 3 #define AAC_SYN_DSE 4 #define AAC_SYN_PCE 5 #define AAC_SYN_FIL 6 #define AAC_SYN_END 7 #ifdef __cplusplus } #endif #endif