1 /* 2 * Copyright (C) 2023 BlueKitchen GmbH 3 * 4 * Redistribution and use in source and binary forms, with or without 5 * modification, are permitted provided that the following conditions 6 * are met: 7 * 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. Neither the name of the copyright holders nor the names of 14 * contributors may be used to endorse or promote products derived 15 * from this software without specific prior written permission. 16 * 4. Any redistribution, use, or modification is done solely for 17 * personal benefit and not for any commercial purpose or for 18 * monetary gain. 19 * 20 * THIS SOFTWARE IS PROVIDED BY BLUEKITCHEN GMBH AND CONTRIBUTORS 21 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 22 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 23 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL BLUEKITCHEN 24 * GMBH OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, 25 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, 26 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS 27 * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED 28 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 29 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF 30 * THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 * 33 * Please inquire about commercial licensing options at 34 * [email protected] 35 * 36 */ 37 38 /** 39 * @title HFP Audio Encoder 40 * @brief Create SCO packet with H2 Synchronization Header and encoded audio samples 41 */ 42 43 #ifndef HFP_CODEC_H 44 #define HFP_CODEC_H 45 46 #include "btstack_config.h" 47 48 #include "hfp.h" // HFP_CODEC_xxx 49 50 #ifdef ENABLE_HFP_WIDE_BAND_SPEECH 51 #include "btstack_sbc.h" 52 #endif 53 54 #ifdef ENABLE_HFP_SUPER_WIDE_BAND_SPEECH 55 #include "btstack_lc3_google.h" 56 #endif 57 58 #include <stdint.h> 59 60 #if defined __cplusplus 61 extern "C" { 62 #endif 63 64 #define SCO_FRAME_SIZE 60 65 66 // HFP H2 67 68 #define HFP_H2_SYNC_FRAME_SIZE 60 69 70 // HFP H2 Framing 71 typedef struct { 72 uint8_t sequence_number; 73 } hfp_h2_framing_t; 74 75 /** 76 * @brief Init HFP H2 Framing state 77 * @param hfp_h2_framing 78 */ 79 void hfp_h2_framing_init(hfp_h2_framing_t * hfp_h2_framing); 80 81 /** 82 * @brief Add next H2 Header 83 * @param hfp_h2_framing 84 * @param buffer [2] 85 */ 86 void hfp_h2_framing_add_header(hfp_h2_framing_t * hfp_h2_framing, uint8_t * buffer); 87 88 89 struct hfp_codec { 90 // to allow for 24 byte USB payloads, we encode up to two SCO packets 91 uint8_t sco_packet[2*SCO_FRAME_SIZE]; 92 uint16_t read_pos; 93 uint16_t write_pos; 94 uint16_t samples_per_frame; 95 hfp_h2_framing_t h2_framing; 96 void (*encode)(struct hfp_codec * hfp_codec, int16_t * pcm_samples); 97 #ifdef ENABLE_HFP_WIDE_BAND_SPEECH 98 btstack_sbc_encoder_state_t msbc_state; 99 #endif 100 #ifdef ENABLE_HFP_SUPER_WIDE_BAND_SPEECH 101 const btstack_lc3_encoder_t * lc3_encoder; 102 btstack_lc3_encoder_google_t lc3_encoder_context; 103 #endif 104 }; 105 106 /* API_START */ 107 108 typedef struct hfp_codec hfp_codec_t; 109 110 /** 111 * @brief Initialize HFP Audio Codec 112 * @note btstack_assert if codec_id is not supported 113 * @param hfp_codec 114 * @param codec_id see HFP_CODEC_xxx in hfp.h 115 * @return status 116 */ 117 void hfp_codec_init(hfp_codec_t * hfp_codec, uint8_t codec_id); 118 119 /** 120 * @brief Get number of audio samples per HFP SCO frame 121 * @param hfp_codec 122 * @return num audio samples per 7.5ms SCO packet 123 */ 124 uint16_t hfp_codec_num_audio_samples_per_frame(const hfp_codec_t * hfp_codec); 125 126 /** 127 * @brief Checks if next frame can be encoded 128 * @param hfp_codec 129 */ 130 bool hfp_codec_can_encode_audio_frame_now(const hfp_codec_t * hfp_codec); 131 132 /** 133 * Get number of bytes ready for sending 134 * @param hfp_codec 135 * @return num bytes ready for current packet 136 */ 137 uint16_t hfp_codec_num_bytes_available(const hfp_codec_t * hfp_codec); 138 139 /** 140 * Encode audio samples for HFP SCO packet 141 * @param hfp_codec 142 * @param pcm_samples - complete audio frame of hfp_msbc_num_audio_samples_per_frame int16 samples 143 */ 144 void hfp_codec_encode_audio_frame(hfp_codec_t * hfp_codec, int16_t * pcm_samples); 145 146 /** 147 * Read from stream into SCO packet buffer 148 * @param hfp_codec 149 * @param buffer to store stream 150 * @param size num bytes to read from stream 151 */ 152 void hfp_codec_read_from_stream(hfp_codec_t * hfp_codec, uint8_t * buffer, uint16_t size); 153 154 /** 155 * @param hfp_codec 156 */ 157 void hfp_codec_deinit(hfp_codec_t * hfp_codec); 158 159 /* API_END */ 160 161 #if defined __cplusplus 162 } 163 #endif 164 165 #endif 166