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a2dp_sink_demo: use built-in btstack_sample_rate_compensation module

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Dirk Helbig 2023-01-26 17:36:35 +01:00 committed by Matthias Ringwald
parent ef026fa8a3
commit bbbd19ba43
2 changed files with 13 additions and 122 deletions
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2
example/Makefile.inc
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@ -484,7 +484,7 @@ hid_mouse_demo: ${CORE_OBJ} ${COMMON_OBJ} ${CLASSIC_OBJ} ${SDP_CLIENT} btstack_r
a2dp_source_demo: ${CORE_OBJ} ${COMMON_OBJ} ${CLASSIC_OBJ} ${SDP_CLIENT} ${SBC_ENCODER_OBJ} ${AVDTP_OBJ} ${HXCMOD_PLAYER_OBJ} avrcp.o avrcp_controller.o avrcp_target.o a2dp_source_demo.c
${CC} $^ ${CFLAGS} ${LDFLAGS} -o $@
a2dp_sink_demo: ${CORE_OBJ} ${COMMON_OBJ} ${CLASSIC_OBJ} ${SDP_CLIENT} ${SBC_DECODER_OBJ} ${AVDTP_OBJ} avrcp.o avrcp_controller.o avrcp_target.o btstack_resample.o a2dp_sink_demo.c
a2dp_sink_demo: ${CORE_OBJ} ${COMMON_OBJ} ${CLASSIC_OBJ} ${SDP_CLIENT} ${SBC_DECODER_OBJ} ${AVDTP_OBJ} avrcp.o avrcp_controller.o avrcp_target.o btstack_resample.o btstack_sample_rate_compensation.o a2dp_sink_demo.c
${CC} $^ ${CFLAGS} ${LDFLAGS} -o $@
avrcp_browsing_client: ${CORE_OBJ} ${COMMON_OBJ} ${CLASSIC_OBJ} ${SDP_CLIENT} ${AVRCP_OBJ} ${AVDTP_OBJ} avrcp_browsing_client.c

133
example/a2dp_sink_demo.c
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@ -68,6 +68,7 @@
#include <string.h>
#include "btstack.h"
#include "btstack_sample_rate_compensation.h"
#include "btstack_resample.h"
//#define AVRCP_BROWSING_ENABLED
@ -120,7 +121,7 @@ static btstack_sbc_mode_t mode = SBC_MODE_STANDARD;
// below 30: add samples, 30-40: fine, above 40: drop samples
#define OPTIMAL_FRAMES_MIN 60
#define OPTIMAL_FRAMES_MAX 80
#define ADDITIONAL_FRAMES 20
#define ADDITIONAL_FRAMES 30
static uint8_t sbc_frame_storage[(OPTIMAL_FRAMES_MAX + ADDITIONAL_FRAMES) * MAX_SBC_FRAME_SIZE];
static btstack_ring_buffer_t sbc_frame_ring_buffer;
static unsigned int sbc_frame_size;
@ -317,119 +318,7 @@ static int a2dp_and_avrcp_setup(void){
}
/* LISTING_END */
#define FTOQ15(a) ((signed)((a)*(UINT16_C(1)<<15)+0.5f))
#define FTOQ8(a) ((signed)((a)*(UINT16_C(1)<<8)+0.5f))
#define FTOQ7(a) ((signed)((a)*(UINT16_C(1)<<7)+0.5f))
#define Q16TOF(a) ((float)(a)/(UINT32_C(1)<<16))
#define Q15TOF(a) ((float)(a)/(UINT32_C(1)<<15))
#define Q8TOF(a) ((float)(a)/(UINT32_C(1)<<8))
#define Q7TOF(a) ((float)(a)/(UINT32_C(1)<<7))
#define DEBUG_RATIO_CALCULATION
typedef struct {
uint32_t count; // 17bit are usable to count samples, recommended for max 96kHz
uint32_t last; // time stamp of last measurement
uint32_t rate_state; // unsigned Q17.8
uint32_t ratio_state; // unsigned Q16.16
uint32_t constant_playback_sample_rate; // playback sample rate if no real one is available
#ifdef DEBUG_RATIO_CALCULATION
double sample_rate;
double ratio;
#endif
} ratio_measure_t;
#define RATE_SCALE (8)
#define RATIO_SCALE (16)
static void ratio_measure_reset( ratio_measure_t *me );
static void ratio_measure_init( ratio_measure_t *me, uint32_t sample_rate, uint32_t ratioQ15 );
static void ratio_measure_update( ratio_measure_t *me, uint32_t samples );
static void ratio_measure_reset( ratio_measure_t *me ) {
me->count = 0;
me->last = 0;
}
static void ratio_measure_init( ratio_measure_t *me, uint32_t sample_rate, uint32_t ratioQ15 ) {
ratio_measure_reset( me );
me->ratio_state = ratioQ15 << 1; // Q15 to Q16 is one left shift
me->rate_state = sample_rate << RATE_SCALE;
#ifdef DEBUG_RATIO_CALCULATION
me->ratio = Q15TOF(ratioQ15);
me->sample_rate = sample_rate;
#endif
}
static void ratio_measure_update( ratio_measure_t *me, uint32_t samples ) {
if( me->last == 0 ) {
me->count = 0;
me->last = btstack_run_loop_get_time_ms();
}
uint32_t current = btstack_run_loop_get_time_ms();
int32_t delta = current - me->last;
if( delta >= 1000 ) {
const btstack_audio_sink_t * audio_sink = btstack_audio_sink_get_instance();
uint32_t playback_sample_rate = me->constant_playback_sample_rate;
// update playback sample rate if we know better
if (audio_sink){
playback_sample_rate = audio_sink->get_samplerate();
}
printf("current playback sample rate: %d\n", playback_sample_rate );
#ifdef DEBUG_RATIO_CALCULATION
{
double current_sample_rate = me->count*(1000./delta);
double current_ratio = me->sample_rate/playback_sample_rate;
// exponential weighted moving average
const double rate_decay = 0.025;
me->sample_rate += rate_decay * (current_sample_rate-me->sample_rate);
// exponential weighted moving average
static const double ratio_decay = 1.3;
me->ratio += ratio_decay * (current_ratio-me->ratio);
log_debug("current l2cap sample rate: %f (%d %d)", current_sample_rate, delta, me->count );
log_debug("current ratio: %f", current_ratio);
log_debug("calculated ratio: %f", me->ratio );
}
#endif
uint32_t fixed_rate = (me->count*(UINT16_C(1)<<15))/delta*1000; // sample rate as Q15
uint32_t fixed_ratio = (me->rate_state<<7)/playback_sample_rate; // Q15
printf("fp current l2cap sample rate: %f (%d %d)\n", Q15TOF(fixed_rate), delta, me->count);
me->last = current;
me->count = 0;
if( fixed_rate > FTOQ15(50000.f) )
goto no_adaption;
// fixed point exponential weighted moving average
const int16_t rate_decay = FTOQ15(0.025f);
uint32_t rate = me->rate_state >> 8; // integer part only
me->rate_state += (rate_decay * (int32_t)((fixed_rate>>15)-rate)) >> (15-8); // Q8;
// fixed point exponential weighted moving average
const int16_t ratio_decay = FTOQ8(1.3f);
me->ratio_state += (ratio_decay * (int32_t)((fixed_ratio<<1)-me->ratio_state)) >> (16-8); // Q16
printf("sbc buffer level : %d\n", btstack_ring_buffer_bytes_available(&sbc_frame_ring_buffer));
printf("fp current ratio : %f\n", Q15TOF(fixed_ratio));
printf("fp calculated ratio: %f\n", Q16TOF(me->ratio_state));
uint32_t scaleQ16 = me->ratio_state;
printf("scale factor Q16: %d\n", scaleQ16);
btstack_resample_set_factor(&resample_instance, scaleQ16);
}
no_adaption:
me->count += samples;
}
ratio_measure_t sample_rate_adaption;
btstack_sample_rate_compensation_t sample_rate_adaption;
static void playback_handler(int16_t * buffer, uint16_t num_audio_frames){
@ -503,7 +392,7 @@ static void handle_pcm_data(int16_t * data, int num_audio_frames, int num_channe
static int media_processing_init(media_codec_configuration_sbc_t * configuration){
if (media_initialized) return 0;
ratio_measure_init( &sample_rate_adaption, configuration->sampling_frequency, FTOQ15(1.f) );
btstack_sample_rate_compensation_init( &sample_rate_adaption, btstack_run_loop_get_time_ms(), configuration->sampling_frequency, FLOAT_TO_Q15(1.f) );
btstack_sbc_decoder_init(&state, mode, handle_pcm_data, NULL);
@ -529,7 +418,7 @@ static int media_processing_init(media_codec_configuration_sbc_t * configuration
static void media_processing_start(void){
if (!media_initialized) return;
ratio_measure_reset( &sample_rate_adaption );
btstack_sample_rate_compensation_reset( &sample_rate_adaption, btstack_run_loop_get_time_ms() );
// setup audio playback
const btstack_audio_sink_t * audio = btstack_audio_sink_get_instance();
if (audio){
@ -594,11 +483,6 @@ static void handle_l2cap_media_data_packet(uint8_t seid, uint8_t *packet, uint16
avdtp_sbc_codec_header_t sbc_header;
if (!read_sbc_header(packet, size, &pos, &sbc_header)) return;
// update sample rate compensation
if( audio_stream_started ) {
ratio_measure_update( &sample_rate_adaption, sbc_header.num_frames*128 );
}
const btstack_audio_sink_t * audio = btstack_audio_sink_get_instance();
// process data right away if there's no audio implementation active, e.g. on posix systems to store as .wav
if (!audio){
@ -606,6 +490,13 @@ static void handle_l2cap_media_data_packet(uint8_t seid, uint8_t *packet, uint16
return;
}
// update sample rate compensation
if( audio_stream_started && (audio != NULL)) {
uint32_t resampling_factor = btstack_sample_rate_compensation_update( &sample_rate_adaption, btstack_run_loop_get_time_ms(), sbc_header.num_frames*128, audio->get_samplerate() );
btstack_resample_set_factor(&resample_instance, resampling_factor);
// printf("sbc buffer level : %d\n", btstack_ring_buffer_bytes_available(&sbc_frame_ring_buffer));
}
// store sbc frame size for buffer management
sbc_frame_size = (size-pos)/ sbc_header.num_frames;