jitterbuf: an application-independent jitterbuffer jitterbuf.c More...
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Data Structures | |
struct | jb_conf |
struct | jb_frame |
struct | jb_info |
struct | jitterbuf |
Defines | |
configuration constants | |
#define | JB_ADJUST_DELAY 40 |
#define | JB_HISTORY_DROPPCT 3 |
#define | JB_HISTORY_DROPPCT_MAX 4 |
#define | JB_HISTORY_MAXBUF_SZ JB_HISTORY_SZ * JB_HISTORY_DROPPCT_MAX / 100 |
#define | JB_HISTORY_SZ 500 |
#define | JB_TARGET_EXTRA 40 |
Typedefs | |
typedef void(* | jb_output_function_t )(const char *fmt,...) |
Enumerations | |
enum | jb_frame_type { JB_TYPE_CONTROL, JB_TYPE_VOICE, JB_TYPE_VIDEO, JB_TYPE_SILENCE } |
enum | jb_return_code { JB_OK, JB_EMPTY, JB_NOFRAME, JB_INTERP, JB_DROP, JB_SCHED } |
Functions | |
void | jb_destroy (jitterbuf *jb) |
destroy jitterbuf | |
enum jb_return_code | jb_get (jitterbuf *jb, jb_frame *frame, long now, long interpl) |
get a frame for time now (receiver's time) return value is one of JB_OK: You've got frame! JB_DROP: Here's an audio frame you should just drop. Ask me again for this time.. JB_NOFRAME: There's no frame scheduled for this time. JB_INTERP: Please interpolate an interpl-length frame for this time (either we need to grow, or there was a lost frame) JB_EMPTY: The jb is empty. | |
enum jb_return_code | jb_getall (jitterbuf *jb, jb_frame *frameout) |
unconditionally get frames from jitterbuf until empty | |
enum jb_return_code | jb_getinfo (jitterbuf *jb, jb_info *stats) |
get jitterbuf info: only "statistics" may be valid | |
jitterbuf * | jb_new (void) |
new jitterbuf | |
long | jb_next (jitterbuf *jb) |
when is the next frame due out, in receiver's time (0=EMPTY) This value may change as frames are added (esp non-audio frames) | |
enum jb_return_code | jb_put (jitterbuf *jb, void *data, const enum jb_frame_type type, long ms, long ts, long now) |
queue a frame | |
void | jb_reset (jitterbuf *jb) |
reset jitterbuf | |
enum jb_return_code | jb_setconf (jitterbuf *jb, jb_conf *conf) |
set jitterbuf conf | |
void | jb_setoutput (jb_output_function_t err, jb_output_function_t warn, jb_output_function_t dbg) |
jitterbuf: an application-independent jitterbuffer jitterbuf.c
Definition in file jitterbuf.h.
#define JB_ADJUST_DELAY 40 |
ms between growing and shrinking; may not be honored if jitterbuffer runs out of space
Definition at line 44 of file jitterbuf.h.
Referenced by _jb_get().
#define JB_HISTORY_DROPPCT 3 |
what percentage of timestamps should we drop from the history when we examine it; this might eventually be something made configurable
Definition at line 36 of file jitterbuf.h.
Referenced by history_get().
#define JB_HISTORY_DROPPCT_MAX 4 |
the maximum droppct we can handle (say it was configurable).
Definition at line 38 of file jitterbuf.h.
#define JB_HISTORY_MAXBUF_SZ JB_HISTORY_SZ * JB_HISTORY_DROPPCT_MAX / 100 |
the size of the buffer we use to keep the top and botton timestamps for dropping
Definition at line 40 of file jitterbuf.h.
Referenced by history_calc_maxbuf(), history_get(), and history_put().
#define JB_HISTORY_SZ 500 |
Number of historical timestamps to use in calculating jitter and drift
Definition at line 33 of file jitterbuf.h.
Referenced by history_calc_maxbuf(), history_get(), and history_put().
#define JB_TARGET_EXTRA 40 |
amount of additional jitterbuffer adjustment
Definition at line 42 of file jitterbuf.h.
Referenced by jb_reset(), and jb_setconf().
typedef void(* jb_output_function_t)(const char *fmt,...) |
Definition at line 166 of file jitterbuf.h.
enum jb_frame_type |
Definition at line 57 of file jitterbuf.h.
00057 { 00058 /* frame types */ 00059 JB_TYPE_CONTROL, /*!< 0 */ 00060 JB_TYPE_VOICE, /*!< 1 */ 00061 JB_TYPE_VIDEO, /*!< 2 - reserved */ 00062 JB_TYPE_SILENCE /*!< 3 */ 00063 };
enum jb_return_code |
Definition at line 47 of file jitterbuf.h.
void jb_destroy | ( | jitterbuf * | jb | ) |
destroy jitterbuf
Definition at line 101 of file jitterbuf.c.
References ast_free, jitterbuf::free, jb_dbg2, and jb_frame::next.
Referenced by jb_destroy_adaptive(), and pvt_destructor().
00102 { 00103 jb_frame *frame; 00104 jb_dbg2("jb_destroy(%x)\n", jb); 00105 00106 /* free all the frames on the "free list" */ 00107 frame = jb->free; 00108 while (frame != NULL) { 00109 jb_frame *next = frame->next; 00110 ast_free(frame); 00111 frame = next; 00112 } 00113 00114 /* free ourselves! */ 00115 ast_free(jb); 00116 }
enum jb_return_code jb_get | ( | jitterbuf * | jb, | |
jb_frame * | frame, | |||
long | now, | |||
long | interpl | |||
) |
get a frame for time now (receiver's time) return value is one of JB_OK: You've got frame! JB_DROP: Here's an audio frame you should just drop. Ask me again for this time.. JB_NOFRAME: There's no frame scheduled for this time. JB_INTERP: Please interpolate an interpl-length frame for this time (either we need to grow, or there was a lost frame) JB_EMPTY: The jb is empty.
Definition at line 787 of file jitterbuf.c.
References _jb_get(), jitterbuf::info, JB_DROP, JB_INTERP, JB_OK, jb_warn, jb_info::last_voice_ms, jb_frame::ms, and jb_frame::ts.
Referenced by __get_from_jb(), and jb_get_adaptive().
00788 { 00789 enum jb_return_code ret = _jb_get(jb, frameout, now, interpl); 00790 #if 0 00791 static int lastts=0; 00792 int thists = ((ret == JB_OK) || (ret == JB_DROP)) ? frameout->ts : 0; 00793 jb_warn("jb_get(%x,%x,%ld) = %d (%d)\n", jb, frameout, now, ret, thists); 00794 if (thists && thists < lastts) jb_warn("XXXX timestamp roll-back!!!\n"); 00795 lastts = thists; 00796 #endif 00797 if (ret == JB_INTERP) 00798 frameout->ms = jb->info.last_voice_ms; 00799 00800 return ret; 00801 }
enum jb_return_code jb_getall | ( | jitterbuf * | jb, | |
jb_frame * | frameout | |||
) |
unconditionally get frames from jitterbuf until empty
Definition at line 803 of file jitterbuf.c.
References JB_NOFRAME, JB_OK, and queue_getall().
Referenced by complete_transfer(), jb_empty_and_reset_adaptive(), jb_remove_adaptive(), pvt_destructor(), and schedule_delivery().
00804 { 00805 jb_frame *frame; 00806 frame = queue_getall(jb); 00807 00808 if (!frame) { 00809 return JB_NOFRAME; 00810 } 00811 00812 *frameout = *frame; 00813 return JB_OK; 00814 }
enum jb_return_code jb_getinfo | ( | jitterbuf * | jb, | |
jb_info * | stats | |||
) |
get jitterbuf info: only "statistics" may be valid
Definition at line 817 of file jitterbuf.c.
References history_get(), jitterbuf::info, and JB_OK.
Referenced by ast_cli_netstats(), construct_rr(), handle_cli_iax2_show_channels(), and log_jitterstats().
00818 { 00819 00820 history_get(jb); 00821 00822 *stats = jb->info; 00823 00824 return JB_OK; 00825 }
jitterbuf* jb_new | ( | void | ) |
new jitterbuf
Definition at line 88 of file jitterbuf.c.
References ast_calloc, jb_dbg2, and jb_reset().
Referenced by jb_create_adaptive(), and new_iax().
00089 { 00090 jitterbuf *jb; 00091 00092 if (!(jb = ast_calloc(1, sizeof(*jb)))) 00093 return NULL; 00094 00095 jb_reset(jb); 00096 00097 jb_dbg2("jb_new() = %x\n", jb); 00098 return jb; 00099 }
long jb_next | ( | jitterbuf * | jb | ) |
when is the next frame due out, in receiver's time (0=EMPTY) This value may change as frames are added (esp non-audio frames)
Definition at line 769 of file jitterbuf.c.
References jb_info::conf, jb_info::current, jitterbuf::frames, history_get(), jitterbuf::info, JB_LONGMAX, jb_info::last_adjustment, jb_info::next_voice_ts, queue_next(), jb_info::silence_begin_ts, jb_info::target, and jb_conf::target_extra.
Referenced by __get_from_jb(), jb_next_adaptive(), and update_jbsched().
00770 { 00771 if (jb->info.silence_begin_ts) { 00772 if (jb->frames) { 00773 long next = queue_next(jb); 00774 history_get(jb); 00775 /* shrink during silence */ 00776 if (jb->info.target - jb->info.current < -jb->info.conf.target_extra) 00777 return jb->info.last_adjustment + 10; 00778 return next + jb->info.target; 00779 } 00780 else 00781 return JB_LONGMAX; 00782 } else { 00783 return jb->info.next_voice_ts; 00784 } 00785 }
enum jb_return_code jb_put | ( | jitterbuf * | jb, | |
void * | data, | |||
const enum jb_frame_type | type, | |||
long | ms, | |||
long | ts, | |||
long | now | |||
) |
queue a frame
data=frame data, timings (in ms): ms=length of frame (for voice), ts=ts (sender's time) now=now (in receiver's time) return value is one of JB_OK: Frame added. Last call to jb_next() still valid JB_DROP: Drop this frame immediately JB_SCHED: Frame added. Call jb_next() to get a new time for the next frame
Definition at line 527 of file jitterbuf.c.
References check_resync(), jb_info::frames_in, history_put(), jitterbuf::info, jb_dbg2, JB_DROP, JB_OK, JB_SCHED, JB_TYPE_VOICE, queue_put(), and jb_info::resync_offset.
Referenced by jb_put_adaptive(), and schedule_delivery().
00528 { 00529 long delay = now - (ts - jb->info.resync_offset); 00530 jb_dbg2("jb_put(%x,%x,%ld,%ld,%ld)\n", jb, data, ms, ts, now); 00531 00532 if (check_resync(jb, ts, now, ms, type, &delay)) { 00533 return JB_DROP; 00534 } 00535 00536 if (type == JB_TYPE_VOICE) { 00537 /* presently, I'm only adding VOICE frames to history and drift calculations; mostly because with the 00538 * IAX integrations, I'm sending retransmitted control frames with their awkward timestamps through */ 00539 history_put(jb, ts, now, ms, delay); 00540 } 00541 00542 jb->info.frames_in++; 00543 00544 /* if put into head of queue, caller needs to reschedule */ 00545 if (queue_put(jb,data,type,ms,ts)) { 00546 return JB_SCHED; 00547 } 00548 return JB_OK; 00549 }
void jb_reset | ( | jitterbuf * | jb | ) |
reset jitterbuf
Definition at line 74 of file jitterbuf.c.
References jb_info::conf, jb_info::current, jitterbuf::free, jitterbuf::info, JB_TARGET_EXTRA, jb_info::silence_begin_ts, jb_info::target, and jb_conf::target_extra.
Referenced by complete_transfer(), jb_empty_and_reset_adaptive(), jb_new(), and schedule_delivery().
00075 { 00076 /* only save settings and free list */ 00077 jb_conf s = jb->info.conf; 00078 jb_frame *fr = jb->free; 00079 memset(jb, 0, sizeof(*jb)); 00080 jb->info.conf = s; 00081 jb->free = fr; 00082 00083 /* initialize length, using the default value */ 00084 jb->info.current = jb->info.target = jb->info.conf.target_extra = JB_TARGET_EXTRA; 00085 jb->info.silence_begin_ts = -1; 00086 }
enum jb_return_code jb_setconf | ( | jitterbuf * | jb, | |
jb_conf * | conf | |||
) |
set jitterbuf conf
Definition at line 827 of file jitterbuf.c.
References jb_info::conf, jb_info::current, jitterbuf::info, JB_OK, JB_TARGET_EXTRA, jb_conf::max_contig_interp, jb_conf::max_jitterbuf, jb_conf::resync_threshold, jb_info::target, and jb_conf::target_extra.
Referenced by jb_create_adaptive(), and new_iax().
00828 { 00829 /* take selected settings from the struct */ 00830 00831 jb->info.conf.max_jitterbuf = conf->max_jitterbuf; 00832 jb->info.conf.resync_threshold = conf->resync_threshold; 00833 jb->info.conf.max_contig_interp = conf->max_contig_interp; 00834 00835 /* -1 indicates use of the default JB_TARGET_EXTRA value */ 00836 jb->info.conf.target_extra = ( conf->target_extra == -1 ) 00837 ? JB_TARGET_EXTRA 00838 : conf->target_extra 00839 ; 00840 00841 /* update these to match new target_extra setting */ 00842 jb->info.current = jb->info.conf.target_extra; 00843 jb->info.target = jb->info.conf.target_extra; 00844 00845 return JB_OK; 00846 }
void jb_setoutput | ( | jb_output_function_t | err, | |
jb_output_function_t | warn, | |||
jb_output_function_t | dbg | |||
) |
Definition at line 57 of file jitterbuf.c.
Referenced by handle_cli_iax2_set_debug_jb(), and load_module().