xref: /btstack/example/a2dp_source_demo.c (revision 01dc6e35bf6408272848487a7886e19b6f64a597)

/*
 * Copyright (C) 2016 BlueKitchen GmbH
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the name of the copyright holders nor the names of
 *    contributors may be used to endorse or promote products derived
 *    from this software without specific prior written permission.
 * 4. Any redistribution, use, or modification is done solely for
 *    personal benefit and not for any commercial purpose or for
 *    monetary gain.
 *
 * THIS SOFTWARE IS PROVIDED BY BLUEKITCHEN GMBH AND CONTRIBUTORS
 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL MATTHIAS
 * RINGWALD OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
 * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF
 * THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 * Please inquire about commercial licensing options at
 * [email protected]
 *
 */


#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#include "btstack.h"

#include "hxcmod.h"
#include "mods/mod.h"

#define NUM_CHANNELS                2
#define A2DP_SAMPLE_RATE            44100
#define BYTES_PER_AUDIO_SAMPLE      (2*NUM_CHANNELS)
#define AUDIO_TIMEOUT_MS            10
#define TABLE_SIZE_441HZ            100

typedef enum {
    STREAM_SINE,
    STREAM_MOD
} stream_data_source_t;

typedef struct {
    uint16_t a2dp_cid;
    uint8_t  local_seid;

    uint32_t time_audio_data_sent; // ms
    uint32_t acc_num_missed_samples;
    uint32_t samples_ready;
    btstack_timer_source_t audio_timer;
    uint8_t  streaming;
    int      max_media_payload_size;

    uint8_t  sbc_storage[1030];
    uint16_t sbc_storage_count;
    uint8_t  sbc_ready_to_send;
} a2dp_media_sending_context_t;

static  uint8_t media_sbc_codec_capabilities[] = {
    (AVDTP_SBC_44100 << 4) | AVDTP_SBC_STEREO,
    0xFF,//(AVDTP_SBC_BLOCK_LENGTH_16 << 4) | (AVDTP_SBC_SUBBANDS_8 << 2) | AVDTP_SBC_ALLOCATION_METHOD_LOUDNESS,
    2, 53
};

static const int16_t sine_int16[] = {
     0,    2057,    4107,    6140,    8149,   10126,   12062,   13952,   15786,   17557,
 19260,   20886,   22431,   23886,   25247,   26509,   27666,   28714,   29648,   30466,
 31163,   31738,   32187,   32509,   32702,   32767,   32702,   32509,   32187,   31738,
 31163,   30466,   29648,   28714,   27666,   26509,   25247,   23886,   22431,   20886,
 19260,   17557,   15786,   13952,   12062,   10126,    8149,    6140,    4107,    2057,
     0,   -2057,   -4107,   -6140,   -8149,  -10126,  -12062,  -13952,  -15786,  -17557,
-19260,  -20886,  -22431,  -23886,  -25247,  -26509,  -27666,  -28714,  -29648,  -30466,
-31163,  -31738,  -32187,  -32509,  -32702,  -32767,  -32702,  -32509,  -32187,  -31738,
-31163,  -30466,  -29648,  -28714,  -27666,  -26509,  -25247,  -23886,  -22431,  -20886,
-19260,  -17557,  -15786,  -13952,  -12062,  -10126,   -8149,   -6140,   -4107,   -2057,
};

static char * device_name = "A2DP Source BTstack";

#ifdef HAVE_BTSTACK_STDIN
// mac 2011:    static const char * device_addr_string = "04:0C:CE:E4:85:D3";
// pts:         static const char * device_addr_string = "00:1B:DC:08:0A:A5";
// mac 2013:    static const char * device_addr_string = "84:38:35:65:d1:15";
// phone 2013:  static const char * device_addr_string = "D8:BB:2C:DF:F0:F2";
// minijambox:
static const char * device_addr_string = "00:21:3C:AC:F7:38";
// head phones: static const char * device_addr_string = "00:18:09:28:50:18";
// bt dongle:   static const char * device_addr_string = "00:15:83:5F:9D:46";
#endif

static bd_addr_t device_addr;
static uint8_t sdp_a2dp_source_service_buffer[150];
static uint8_t media_sbc_codec_configuration[4];
static a2dp_media_sending_context_t media_tracker;

static uint16_t avrcp_cid;

static stream_data_source_t data_source;

static int sine_phase;

static int hxcmod_initialized;
static modcontext mod_context;
static tracker_buffer_state trkbuf;

static void a2dp_demo_send_media_packet(void){
    int num_bytes_in_frame = btstack_sbc_encoder_sbc_buffer_length();
    int bytes_in_storage = media_tracker.sbc_storage_count;
    uint8_t num_frames = bytes_in_storage / num_bytes_in_frame;
    a2dp_source_stream_send_media_payload(media_tracker.local_seid, media_tracker.sbc_storage, bytes_in_storage, num_frames, 0);
    media_tracker.sbc_storage_count = 0;
    media_tracker.sbc_ready_to_send = 0;
}

static void produce_sine_audio(int16_t * pcm_buffer, int num_samples_to_write){
    int count;
    for (count = 0; count < num_samples_to_write ; count++){
        pcm_buffer[count * 2]     = sine_int16[sine_phase];
        pcm_buffer[count * 2 + 1] = sine_int16[sine_phase];
        sine_phase++;
        if (sine_phase >= TABLE_SIZE_441HZ){
            sine_phase -= TABLE_SIZE_441HZ;
        }
    }
}

static void produce_mod_audio(int16_t * pcm_buffer, int num_samples_to_write){
    hxcmod_fillbuffer(&mod_context, (unsigned short *) &pcm_buffer[0], num_samples_to_write, &trkbuf);
}

static void produce_audio(int16_t * pcm_buffer, int num_samples){
    switch (data_source){
        case STREAM_SINE:
            produce_sine_audio(pcm_buffer, num_samples);
            break;
        case STREAM_MOD:
            produce_mod_audio(pcm_buffer, num_samples);
            break;
    }
}

static int a2dp_demo_fill_sbc_audio_buffer(a2dp_media_sending_context_t * context){
    // perform sbc encodin
    int total_num_bytes_read = 0;
    int num_audio_samples_per_sbc_buffer = btstack_sbc_encoder_num_audio_frames();
    while (context->samples_ready >= num_audio_samples_per_sbc_buffer
        && (context->max_media_payload_size - context->sbc_storage_count) >= btstack_sbc_encoder_sbc_buffer_length()){

        uint8_t pcm_frame[256*BYTES_PER_AUDIO_SAMPLE];

        produce_audio((int16_t *) pcm_frame, num_audio_samples_per_sbc_buffer);
        btstack_sbc_encoder_process_data((int16_t *) pcm_frame);

        uint16_t sbc_frame_size = btstack_sbc_encoder_sbc_buffer_length();
        uint8_t * sbc_frame = btstack_sbc_encoder_sbc_buffer();

        total_num_bytes_read += num_audio_samples_per_sbc_buffer;
        memcpy(&context->sbc_storage[context->sbc_storage_count], sbc_frame, sbc_frame_size);
        context->sbc_storage_count += sbc_frame_size;
        context->samples_ready -= num_audio_samples_per_sbc_buffer;
    }
    return total_num_bytes_read;
}

static void a2dp_demo_audio_timeout_handler(btstack_timer_source_t * timer){
    a2dp_media_sending_context_t * context = (a2dp_media_sending_context_t *) btstack_run_loop_get_timer_context(timer);
    btstack_run_loop_set_timer(&context->audio_timer, AUDIO_TIMEOUT_MS);
    btstack_run_loop_add_timer(&context->audio_timer);
    uint32_t now = btstack_run_loop_get_time_ms();

    uint32_t update_period_ms = AUDIO_TIMEOUT_MS;
    if (context->time_audio_data_sent > 0){
        update_period_ms = now - context->time_audio_data_sent;
    }

    uint32_t num_samples = (update_period_ms * A2DP_SAMPLE_RATE) / 1000;
    context->acc_num_missed_samples += (update_period_ms * A2DP_SAMPLE_RATE) % 1000;

    while (context->acc_num_missed_samples >= 1000){
        num_samples++;
        context->acc_num_missed_samples -= 1000;
    }
    context->time_audio_data_sent = now;
    context->samples_ready += num_samples;

    if (context->sbc_ready_to_send) return;

    a2dp_demo_fill_sbc_audio_buffer(context);

    if ((context->sbc_storage_count + btstack_sbc_encoder_sbc_buffer_length()) > context->max_media_payload_size){
        // schedule sending
        context->sbc_ready_to_send = 1;
        a2dp_source_stream_endpoint_request_can_send_now(context->local_seid);
    }
}

static void a2dp_demo_timer_start(a2dp_media_sending_context_t * context){
    context->max_media_payload_size = a2dp_max_media_payload_size(context->local_seid);
    context->sbc_storage_count = 0;
    context->sbc_ready_to_send = 0;
    context->streaming = 1;
    btstack_run_loop_remove_timer(&context->audio_timer);
    btstack_run_loop_set_timer_handler(&context->audio_timer, a2dp_demo_audio_timeout_handler);
    btstack_run_loop_set_timer_context(&context->audio_timer, context);
    btstack_run_loop_set_timer(&context->audio_timer, AUDIO_TIMEOUT_MS);
    btstack_run_loop_add_timer(&context->audio_timer);
}

static void a2dp_demo_timer_stop(a2dp_media_sending_context_t * context){
    context->time_audio_data_sent = 0;
    context->acc_num_missed_samples = 0;
    context->samples_ready = 0;
    context->streaming = 1;
    context->sbc_storage_count = 0;
    context->sbc_ready_to_send = 0;
    btstack_run_loop_remove_timer(&context->audio_timer);
}

static void a2dp_demo_timer_pause(a2dp_media_sending_context_t * context){
    btstack_run_loop_remove_timer(&context->audio_timer);
}


static void packet_handler(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size){
    UNUSED(channel);
    UNUSED(size);
    uint8_t status;
    uint8_t local_seid;

    switch (packet_type) {

        case HCI_EVENT_PACKET:
            switch (hci_event_packet_get_type(packet)) {
                case HCI_EVENT_A2DP_META:
                    switch (packet[2]){
                        case A2DP_SUBEVENT_STREAM_ESTABLISHED:
                            status = a2dp_subevent_stream_established_get_status(packet);
                            if (status){
                                printf("Stream establishment failed: status 0x%02x.\n", status);
                                break;
                            }
                            local_seid = a2dp_subevent_stream_established_get_local_seid(packet);
                            if (local_seid != media_tracker.local_seid){
                                printf("Stream establishment failed: wrong local seid %d, expected %d.\n", local_seid, media_tracker.local_seid);
                                break;
                            }

                            media_tracker.a2dp_cid = a2dp_subevent_stream_established_get_a2dp_cid(packet);
                            printf("Stream established: a2dp cid 0x%02x, local seid %d, remote seid %d.\n",
                                media_tracker.a2dp_cid, media_tracker.local_seid, a2dp_subevent_stream_established_get_remote_seid(packet));
                            break;

                        case A2DP_SUBEVENT_STREAM_STARTED:
                            a2dp_demo_timer_start(&media_tracker);
                            printf("Stream started.\n");
                            break;

                        case A2DP_SUBEVENT_STREAMING_CAN_SEND_MEDIA_PACKET_NOW:
                            a2dp_demo_send_media_packet();
                            break;

                        case A2DP_SUBEVENT_STREAM_SUSPENDED:
                            printf("Stream paused.\n");
                            a2dp_demo_timer_pause(&media_tracker);
                            break;

                        case A2DP_SUBEVENT_STREAM_RELEASED:
                            printf("Stream released.\n");
                            a2dp_demo_timer_stop(&media_tracker);
                            break;
                        default:
                            printf("AVDTP Source demo: event 0x%02x is not implemented\n", packet[2]);
                            break;
                    }
                    break;
                default:
                    break;
            }
            break;
        default:
            // other packet type
            break;
    }
}

static void avrcp_target_packet_handler(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size){
    UNUSED(channel);
    UNUSED(size);
    bd_addr_t event_addr;
    uint16_t local_cid;
    uint8_t  status = 0xFF;

    if (packet_type != HCI_EVENT_PACKET) return;
    if (hci_event_packet_get_type(packet) != HCI_EVENT_AVRCP_META) return;
    switch (packet[2]){
        case AVRCP_SUBEVENT_CONNECTION_ESTABLISHED: {
            local_cid = avrcp_subevent_connection_established_get_avrcp_cid(packet);
            if (avrcp_cid != 0 && avrcp_cid != local_cid) {
                printf("AVRCP Connection failed, expected 0x%02X l2cap cid, received 0x%02X\n", avrcp_cid, local_cid);
                return;
            }

            status = avrcp_subevent_connection_established_get_status(packet);
            if (status != ERROR_CODE_SUCCESS){
                printf("AVRCP Connection failed: status 0x%02x\n", status);
                avrcp_cid = 0;
                return;
            }
            avrcp_cid = local_cid;
            avrcp_subevent_connection_established_get_bd_addr(packet, event_addr);
            printf("Channel successfully opened: %s, avrcp_cid 0x%02x\n", bd_addr_to_str(event_addr), local_cid);
            return;
        }
        case AVRCP_SUBEVENT_CONNECTION_RELEASED:
            printf("Channel released: avrcp_cid 0x%02x\n", avrcp_subevent_connection_released_get_avrcp_cid(packet));
            avrcp_cid = 0;
            return;
        default:
            printf("A2DP Source/AVRCP Target event not parsed %02x\n", packet[2]);
            break;
    }
}

#ifdef HAVE_BTSTACK_STDIN
static void show_usage(void){
    bd_addr_t      iut_address;
    gap_local_bd_addr(iut_address);
    printf("\n--- Bluetooth A2DP Source/AVRCP Target Demo %s ---\n", bd_addr_to_str(iut_address));
    printf("b      - AVDTP Source create  connection to addr %s\n", device_addr_string);
    printf("B      - AVDTP Source disconnect\n");
    printf("c      - AVRCP Target create connection to addr %s\n", device_addr_string);
    printf("C      - AVRCP Target disconnect\n");

    printf("x      - start streaming sine\n");
    if (hxcmod_initialized){
        printf("z      - start streaming '%s'\n", mod_name);
    }
    printf("p      - pause streaming\n");

    printf("\n--- Bluetooth  AVRCP Target Commands %s ---\n", bd_addr_to_str(iut_address));
    printf("Ctrl-c - exit\n");
    printf("---\n");
}

static void stdin_process(char cmd){
    switch (cmd){
        case 'b':
            printf(" - Create AVDTP Source connection to addr %s.\n", bd_addr_to_str(device_addr));
            a2dp_source_establish_stream(device_addr, media_tracker.local_seid, &media_tracker.a2dp_cid);
            break;
        case 'B':
            printf(" - AVDTP Source Disconnect\n");
            a2dp_source_disconnect(media_tracker.a2dp_cid);
            break;
        case 'c':
            printf(" - Create AVRCP Target connection to addr %s.\n", bd_addr_to_str(device_addr));
            avrcp_target_connect(device_addr, &avrcp_cid);
            printf(" assigned avrcp cid 0x%02x\n", avrcp_cid);
            break;
        case 'C':
            printf(" - AVRCP Target disconnect\n");
            avrcp_target_disconnect(avrcp_cid);
            break;

        case '\n':
        case '\r':
            break;

        case 'x':
            printf("Playing sine.\n");
            data_source = STREAM_SINE;
            a2dp_source_start_stream(media_tracker.a2dp_cid, media_tracker.local_seid);
            break;
        case 'z':
            printf("Playing mod.\n");
            data_source = STREAM_MOD;
            a2dp_source_start_stream(media_tracker.a2dp_cid, media_tracker.local_seid);
            break;
        case 'p':
            printf("Pause stream.\n");
            a2dp_source_pause_stream(media_tracker.a2dp_cid, media_tracker.local_seid);
            break;

        default:
            show_usage();
            break;
    }
}
#endif


int btstack_main(int argc, const char * argv[]);
int btstack_main(int argc, const char * argv[]){
    UNUSED(argc);
    (void)argv;

    l2cap_init();
    // Initialize AVDTP Source
    a2dp_source_init();
    a2dp_source_register_packet_handler(&packet_handler);

    media_tracker.local_seid = a2dp_source_create_stream_endpoint(AVDTP_AUDIO, AVDTP_CODEC_SBC, media_sbc_codec_capabilities, sizeof(media_sbc_codec_capabilities), media_sbc_codec_configuration, sizeof(media_sbc_codec_configuration));

    // Initialize AVRCP Target
    avrcp_target_init();
    avrcp_target_register_packet_handler(&avrcp_target_packet_handler);

    // Initialize SDP
    sdp_init();
    memset(sdp_a2dp_source_service_buffer, 0, sizeof(sdp_a2dp_source_service_buffer));
    a2dp_source_create_sdp_record(sdp_a2dp_source_service_buffer, 0x10002, 1, NULL, NULL);
    sdp_register_service(sdp_a2dp_source_service_buffer);

    gap_set_local_name(device_name);
    gap_discoverable_control(1);
    gap_set_class_of_device(0x200408);

    hxcmod_initialized = hxcmod_init(&mod_context);
    if (hxcmod_initialized){
        hxcmod_setcfg(&mod_context, A2DP_SAMPLE_RATE, 16, 1, 1, 1);
        hxcmod_load(&mod_context, (void *) &mod_data, mod_len);
        printf("loaded mod '%s', size %u\n", mod_name, mod_len);
    }

#ifdef HAVE_BTSTACK_STDIN
    // parse human readable Bluetooth address
    sscanf_bd_addr(device_addr_string, device_addr);
    btstack_stdin_setup(stdin_process);
#endif
    // turn on!
    hci_power_control(HCI_POWER_ON);
    return 0;
}