耳机(Headset)
1. 功能概述
本工程用于耳机等设备场景，主要功能有
1.作为a2dp sink接收对端传输的音乐数据2.作为avrcp ct/tg对端进行控制（播放暂停等）3.作为hfp hf接收对端传输的语音数据4.ble gatt server/gatt client（可以详见Central工程相关介绍）
1.1 软件规格
- a2dp:
avdtp sink
- avrcp:
tg
ct
- hfp:
hf
- ble:
gap
gatt server
gatt client
smp legacy pair/secure connection pair
1.2 代码路径及编译命令
Demo路径：./projects/bluetooth/headset
编译命令：
make bk7258 PROJECT=bluetooth/headset
2. cmd命令简介
2.1 a2dp/avrcp
headset connect <xx:xx:xx:xx:xx:xx>
主动连接对端设备
headset disconnect <xx:xx:xx:xx:xx:xx>
断开连接
headset play
播放
headset pause
暂停
headset next
下一曲
headset prev
上一曲
headset rewind [msec]
快退，可指定时间
headset fast_forward [msec]
快进，可指定时间
headset vol_up
音量增加
headset vol_down
音量减少
headset pair_mode
进入配对模式
3. 框架图
3.1 软件模块架构图
如下图所示，bluetooth负责音乐数据接收以及语音数据接收和发送；audio负责对音乐和语音数据解码播放以及采集MIC数据并编码；storage负责蓝牙关键信息存储，比如加密key
Figure 1. software module architecture
3.2 流程图
A2DP工作流程和HFP工作流程见下图
Figure 2. a2dp flow chart
Figure 3. hfp flow chart
4. 配置
4.1 demo开启配置
在工程路径下config/bk7258/config，修改宏来配置是否开启A2DP和HFP demo，当前默认开启A2DP demo；
//开启A2DP demoCONFIG_A2DP_SINK_DEMO=y//开启HFP demoCONFIG_HFP_HF_DEMO=y
4.2 codec方式配置
4.2.1 A2DP
CONFIG_SBC
CONFIG_AAC_DECODER
a2dp_sink_demo_init的参数
支持SBC
Y
N
0
支持AAC
Y
Y
1
4.2.1 HFP
CONFIG_SBC
hfp_hf_demo_init的参数
支持CVSD
N
0
支持mSBC
Y
1
5. 代码讲解
5.1 A2DP demo
5.1.1 获得蓝牙上报的音乐数据
void bt_audio_sink_media_data_ind(const uint8_t *data, uint16_t data_len)
{
bt_audio_sink_demo_msg_t demo_msg;
int rc = -1;
os_memset(&demo_msg, 0x0, sizeof(bt_audio_sink_demo_msg_t));
if (bt_audio_sink_demo_msg_que == NULL)
{
return;
}
demo_msg.data = (char *) os_malloc(data_len);
if (demo_msg.data == NULL)
{
LOGE("%s, malloc failed\r\n", __func__);
return;
}
os_memcpy(demo_msg.data, data, data_len);
demo_msg.type = BT_AUDIO_D2DP_DATA_IND_MSG;
demo_msg.len = data_len;
//发送给audio_sink_demo task
rc = rtos_push_to_queue(&bt_audio_sink_demo_msg_que, &demo_msg, BEKEN_NO_WAIT);
...
}
5.1.2 把音乐数据按帧暂存ring buffer
void bt_audio_sink_demo_main(void *arg)
{
...
case BT_AUDIO_D2DP_DATA_IND_MSG:
{
...
uint8 *fb = (uint8_t *)msg.data;
if(s_spk_is_started)
{
//对sbc格式数据按帧存入ring buffer
if (CODEC_AUDIO_SBC == bt_audio_a2dp_sink_codec.type)
{
uint8_t payload_header = *fb++;
uint8_t frame_num = payload_header&0xF;
if(msg.len - 1 != frame_length*frame_num)
{
LOGI("recv undef sbc, payload_header %d, payload_len: %d, frame_num:%d \r\n", payload_header, msg.len - 1, frame_num);
}
for(uint8_t i=0;i<frame_num;i++)
{
if (ring_buffer_node_get_free_nodes(&s_a2dp_frame_nodes))
{
uint8_t *node = ring_buffer_node_get_write_node(&s_a2dp_frame_nodes);
os_memcpy(node, fb, frame_length);
fb += frame_length;
}
else
{
LOGI("A2DP frame nodes buffer(sbc) is full\n");
//os_free(msg.data);
break;
}
}
}
#if CONFIG_AAC_DECODER
//先解析出AAC格式数据的帧长度，再按帧长度存入ring buffer
else if(CODEC_AUDIO_AAC == bt_audio_a2dp_sink_codec.type)
{
// LOGI("-> %d \n", msg.len);
uint8_t *inbuf = &fb[9];
uint32_t inlen = 0;
uint8_t len = 255;
do
{
inlen += len = *inbuf++;
}
while (len == 255);
{
if (ring_buffer_node_get_free_nodes(&s_a2dp_frame_nodes))
{
uint8_t *node = ring_buffer_node_get_write_node(&s_a2dp_frame_nodes);
*((uint32_t *)node) = inlen;
os_memcpy(node + 4, inbuf, inlen);
}
else
{
LOGI("A2DP frame nodes buffer(aac) is full\n");
os_free(msg.data);
break;
}
}
}
#endif
else
{
LOGE("%s, Unsupported a2dp codec %d \r\n", __func__, bt_audio_a2dp_sink_codec.type);
}
if(a2dp_speaker_sema)
{
rtos_set_semaphore(&a2dp_speaker_sema);
}
}
...
}
break;
...
}
5.1.3 解码音乐数据
static void speaker_task(void *arg)
{
...
for (; i < s_frame; i++)
{
//从ring buffer读取
uint8_t *inbuf = ring_buffer_node_get_read_node(&s_a2dp_frame_nodes);
bk_err_t ret;
if (CODEC_AUDIO_SBC == bt_audio_a2dp_sink_codec.type)
{
//进行sbc解码
ret = bk_sbc_decoder_frame_decode(&bt_audio_sink_sbc_decoder, inbuf, frame_length);
if (ret < 0)
{
LOGE("sbc_decoder_decode error <%d>\n", ret);
continue;
}
int16_t *dst = (int16_t*)bt_audio_sink_sbc_decoder.pcm_sample;
int16_t w_len = bt_audio_sink_sbc_decoder.pcm_length * 4;
if(CONFIG_BOARD_AUDIO_CHANNLE_NUM == 1)
{
for(int i=0; i<bt_audio_sink_sbc_decoder.pcm_length * 2; i++)
{
dst[i] = dst[i*2];
}
w_len = bt_audio_sink_sbc_decoder.pcm_length * 2;
}
//发送解码数据给speaker
int size = raw_stream_write(raw_write, (char *)dst, w_len);
if (size <= 0)
{
LOGE("raw_stream_write size fail: %d \n", size);
break;
}
else
{
//LOGI("raw_stream_write size: %d \n", size);
}
}
#if (CONFIG_AAC_DECODER)
else if(CODEC_AUDIO_AAC == bt_audio_a2dp_sink_codec.type)
{
uint32_t len = *(uint32_t *)inbuf;
// LOGI("<- %d \n", len);
uint8_t *out_buf = 0;
uint32_t out_len = 0;
//进行aac解码
ret = bk_aac_decoder_decode(&bt_audio_sink_aac_decoder, (inbuf+4), len, &out_buf, &out_len);
if(ret == 0)
{
int16_t *dst = (int16_t*)out_buf;
int16_t w_len = out_len;
if(CONFIG_BOARD_AUDIO_CHANNLE_NUM == 1)
{
for(uint16_t i=0;i<out_len/2;i++)
{
dst[i] = dst[i*2];
}
w_len = out_len/2;
}
//发送解码数据给speaker
int size = raw_stream_write(raw_write, (char *)dst, w_len);
if (size <= 0)
{
LOGE("raw_stream_write size fail: %d \n", size);
break;
}
else
{
// LOGI("raw_stream_write size: %d \n", size);
}
}else
{
LOGE("sbc_decoder_decode error <%d>\n", ret);
}
}
#endif
else
{
LOGE("unsupported codec!! /n");
}
}
...
}
5.2 HFP demo
5.2.1 获得蓝牙上报的语音数据
void bt_audio_hfp_client_voice_data_ind(const uint8_t *data, uint16_t data_len)
{
bt_audio_hf_demo_msg_t demo_msg;
int rc = -1;
os_memset(&demo_msg, 0x0, sizeof(bt_audio_hf_demo_msg_t));
if (bt_audio_hf_demo_msg_que == NULL)
return;
demo_msg.data = (char *) os_malloc(data_len);
if (demo_msg.data == NULL)
{
LOGI("%s, malloc failed\r\n", __func__);
return;
}
os_memcpy(demo_msg.data, data, data_len);
demo_msg.type = BT_AUDIO_VOICE_IND_MSG;
demo_msg.len = data_len;
//发送给audio_hf_demo task
rc = rtos_push_to_queue(&bt_audio_hf_demo_msg_que, &demo_msg, BEKEN_NO_WAIT);
...
}
5.2.2 解码语音数据
void bt_audio_hf_demo_main(void *arg)
{
...
case BT_AUDIO_VOICE_IND_MSG:
{
...
//对msbc格式语音数据进行解码
if (CODEC_VOICE_MSBC == bt_audio_hfp_hf_codec)
{
fb += 2; //Skip Synchronization Header
ret = bk_sbc_decoder_frame_decode(&bt_audio_hf_sbc_decoder, fb, msg.len - 2);
// LOGI("sbc decod %d \n", ret);
if (ret < 0)
{
LOGE("msbc decode fail, ret:%d\n", ret);
}
else
{
ret = BK_OK;
fb = (uint8_t*)bt_audio_hf_sbc_decoder.pcm_sample;
packet_len = r_len = SCO_MSBC_SAMPLES_PER_FRAME*2;
packet_num = 4;
}
}
else
{
packet_len = r_len = SCO_CVSD_SAMPLES_PER_FRAME * 2;
packet_num = 8;
}
if(ret == BK_OK)
{
...
//把原生语音数据存入hf_speaker_buffer
os_memcpy(hf_speaker_buffer + hf_speaker_data_count, fb, r_len);
hf_speaker_data_count += r_len;
if (hf_speaker_data_count >= packet_len * packet_num)
{
if (hf_speaker_sema)
{
rtos_set_semaphore(&hf_speaker_sema);
}
hf_speaker_data_count -= packet_len * packet_num;
}
}else
{
//LOGE("write spk data fail \r\n");
}
os_free(msg.data);
}
break;
...
}
5.2.3 播放语音数据
static void speaker_task(void *arg)
{
...
while (hf_auido_start)
{
rtos_get_semaphore(&hf_speaker_sema, BEKEN_WAIT_FOREVER);
//把hf_speaker_buffer中的语音数据发给SPEAKER
int size = raw_stream_write(raw_write, (char *)hf_speaker_buffer, packet_len);
if (size <= 0)
{
LOGE("raw_stream_write size: %d \n", size);
break;
}
else
{
//LOGI("raw_stream_write size: %d \n", size);
}
}
...
}
5.2.4 获取上行MIC数据
static void mic_task(void *arg)
{
...
while (hf_auido_start)
{
if (hf_mic_data_count+read_size < sizeof(hf_mic_sco_data))
{
//获取MIC数据
int size = raw_stream_read(raw_read, (char *)(hf_mic_sco_data + hf_mic_data_count), read_size);
if (size > 0)
{
...
while (hf_mic_data_count >= send_len)
{
//根据选用的编码格式决定是否进行msbc编码
if (CODEC_VOICE_MSBC == bt_audio_hfp_hf_codec)
{
int32_t produced = sbc_encoder_encode(&bt_audio_hf_sbc_encoder, (int16_t *)(hf_mic_sco_data + send_len * i));
// LOGI("[send_mic_data_to_air_msbc] %d \r\n",produced);
//发送编码后的语音数据给蓝牙
bk_bt_hf_client_voice_out_write(hfp_peer_addr, (uint8_t *)&bt_audio_hf_sbc_encoder.stream [ -2 ], produced + 2);
}else
{
//发送未编码的语音数据给蓝牙
bk_bt_hf_client_voice_out_write(hfp_peer_addr, hf_mic_sco_data + send_len * i, send_len);
}
i++;
hf_mic_data_count -= send_len;
}
if (hf_mic_data_count)
{
os_memmove(hf_mic_sco_data, hf_mic_sco_data + send_len * i, hf_mic_data_count);
}
}
}
else
{
LOGE("MIC BUFFER FULL \r\n");
hf_mic_data_count = 0;
}
}
...
}