1 /* 2 * Copyright (C) 2014 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 MATTHIAS 24 * RINGWALD 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 // 40 // HFP mSBC encoder wrapper 41 // 42 // ***************************************************************************** 43 44 #include "btstack_config.h" 45 46 #include <string.h> 47 48 #include "btstack_debug.h" 49 #include "btstack_sbc.h" 50 #include "hfp_msbc.h" 51 52 #define MSBC_FRAME_SIZE 57 53 #define MSBC_HEADER_H2_SIZE 2 54 #define MSBC_PADDING_SIZE 1 55 #define MSBC_EXTRA_SIZE (MSBC_HEADER_H2_SIZE + MSBC_PADDING_SIZE) 56 57 static const uint8_t msbc_header_h2_byte_0 = 1; 58 static const uint8_t msbc_header_h2_byte_1_table[] = { 0x08, 0x38, 0xc8, 0xf8 }; 59 60 static btstack_sbc_encoder_state_t state; 61 static int msbc_sequence_number; 62 63 static uint8_t msbc_buffer[2*(MSBC_FRAME_SIZE + MSBC_EXTRA_SIZE)]; 64 static int msbc_buffer_offset = 0; 65 66 void hfp_msbc_init(void){ 67 btstack_sbc_encoder_init(&state, SBC_MODE_mSBC, 16, 8, 0, 16000, 26); 68 msbc_buffer_offset = 0; 69 msbc_sequence_number = 0; 70 } 71 72 int hfp_msbc_can_encode_audio_frame_now(void){ 73 return sizeof(msbc_buffer) - msbc_buffer_offset >= MSBC_FRAME_SIZE + MSBC_EXTRA_SIZE; 74 } 75 76 void hfp_msbc_encode_audio_frame(int16_t * pcm_samples){ 77 if (!hfp_msbc_can_encode_audio_frame_now()) return; 78 79 // Synchronization Header H2 80 msbc_buffer[msbc_buffer_offset++] = msbc_header_h2_byte_0; 81 msbc_buffer[msbc_buffer_offset++] = msbc_header_h2_byte_1_table[msbc_sequence_number]; 82 msbc_sequence_number = (msbc_sequence_number + 1) & 3; 83 84 // SBC Frame 85 btstack_sbc_encoder_process_data(pcm_samples); 86 memcpy(msbc_buffer + msbc_buffer_offset, btstack_sbc_encoder_sbc_buffer(), MSBC_FRAME_SIZE); 87 msbc_buffer_offset += MSBC_FRAME_SIZE; 88 89 // Final padding to use 60 bytes for 120 audio samples 90 msbc_buffer[msbc_buffer_offset++] = 0; 91 } 92 93 void hfp_msbc_read_from_stream(uint8_t * buf, int size){ 94 int bytes_to_copy = size; 95 if (size > msbc_buffer_offset){ 96 bytes_to_copy = msbc_buffer_offset; 97 log_error("sbc frame storage is smaller then the output buffer"); 98 return; 99 } 100 101 memcpy(buf, msbc_buffer, bytes_to_copy); 102 memmove(msbc_buffer, msbc_buffer + bytes_to_copy, sizeof(msbc_buffer) - bytes_to_copy); 103 msbc_buffer_offset -= bytes_to_copy; 104 } 105 106 int hfp_msbc_num_bytes_in_stream(void){ 107 return msbc_buffer_offset; 108 } 109 110 int hfp_msbc_num_audio_samples_per_frame(void){ 111 return btstack_sbc_encoder_num_audio_samples(); 112 } 113 114 115