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#define JITTER_FLAG_NONE 0 // no flags at all
#define JITTER_FLAG_LATENCY (1 << 0) // keep latency close to target_window_duration
#define JITTER_FLAG_REPEAT (1 << 1) // repeat audio to extrapolate gaps
/* window settings for low latency audio and extrapolation of gaps */
#define JITTER_AUDIO 0.060, 1.000, JITTER_FLAG_LATENCY | JITTER_FLAG_REPEAT
/* window settings for analog data (fax/modem) or digial data (HDLC) */
#define JITTER_DATA 0.100, 0.200, JITTER_FLAG_NONE
typedef struct jitter_frame {
struct jitter_frame *next;
void (*decoder)(uint8_t *src_data, int src_len, uint8_t **dst_data, int *dst_len, void *priv);
void *decoder_priv;
uint8_t marker;
uint16_t sequence;
uint32_t timestamp;
uint32_t ssrc;
int size;
uint8_t data[0];
} jitter_frame_t;
typedef struct jitter {
char name[64];
/* frame properties */
double sample_duration; /* duration of a frame (ms) */
int samples_20ms; /* samples to compensate a gap of unknown size */
/* window properties */
bool unlocked; /* jitter buffer will be locked until some reads from it */
uint32_t window_flags; /* flags to alter behaviour of jitter buffer */
int target_window_size; /* target size of window (frames) */
int max_window_size; /* maximum size of window (frames) */
bool window_valid; /* set, if first frame has been received */
uint32_t window_ssrc; /* current sync source of window */
uint32_t window_timestamp; /* lowest timestamp number in window */
/* reduction of delay */
double delay_interval; /* interval for delay measurement (seconds) */
double delay_counter; /* current counter to count interval (seconds) */
int min_delay; /* minimum delay measured during interval (frames) */
/* list of frames */
jitter_frame_t *frame_list;
/* sample buffer (optional) */
uint8_t *spl_buf; /* current samples buffer */
int spl_pos; /* position of in buffer */
int spl_len; /* total buffer size */
bool spl_valid; /* if buffer has valid frame (not repeated) */
} jitter_t;
int jitter_create(jitter_t *jb, const char *name, double samplerate, double target_window_duration, double max_window_duration, uint32_t window_flags);
void jitter_reset(jitter_t *jb);
void jitter_destroy(jitter_t *jb);
jitter_frame_t *jitter_frame_alloc(void (*decoder)(uint8_t *src_data, int src_len, uint8_t **dst_data, int *dst_len, void *priv), void *decoder_priv, uint8_t *data, int size, uint8_t marker, uint16_t sequence, uint32_t timestamp, uint32_t ssrc);
void jitter_frame_free(jitter_frame_t *jf);
void jitter_frame_get(jitter_frame_t *jf, void (**decoder)(uint8_t *src_data, int src_len, uint8_t **dst_data, int *dst_len, void *priv), void **decoder_priv, uint8_t **data, int *size, uint8_t *marker, uint16_t *sequence, uint32_t *timestamp, uint32_t *ssrc);
void jitter_save(jitter_t *jb, jitter_frame_t *jf);
int32_t jitter_offset(jitter_t *jb);
jitter_frame_t *jitter_load(jitter_t *jb);
void jitter_advance(jitter_t *jb, uint32_t offset);
void jitter_load_samples(jitter_t *jb, uint8_t *spl, int len, size_t sample_size, void (*conceal)(uint8_t *spl, int len, void *priv), void *conceal_priv);
void jitter_conceal_s16(uint8_t *_spl, int len, void __attribute__((unused)) *priv);
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