diff options
Diffstat (limited to 'kopete/protocols/jabber/jingle/libjingle/talk/third_party/ortp/jitterctl.c')
| -rw-r--r-- | kopete/protocols/jabber/jingle/libjingle/talk/third_party/ortp/jitterctl.c | 141 |
1 files changed, 141 insertions, 0 deletions
diff --git a/kopete/protocols/jabber/jingle/libjingle/talk/third_party/ortp/jitterctl.c b/kopete/protocols/jabber/jingle/libjingle/talk/third_party/ortp/jitterctl.c new file mode 100644 index 00000000..5f236f71 --- /dev/null +++ b/kopete/protocols/jabber/jingle/libjingle/talk/third_party/ortp/jitterctl.c @@ -0,0 +1,141 @@ +/* + The oRTP library is an RTP (Realtime Transport Protocol - rfc1889) stack. + Copyright (C) 2001 Simon MORLAT simon.morlat@linphone.org + + This library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + This library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with this library; if not, write to the Free Software + Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA +*/ +/*************************************************************************** + * jitterctl.c + * + * Mon Nov 8 11:53:21 2004 + * Copyright 2004 Simon MORLAT + * Email simon.morlat@linphone.org + ****************************************************************************/ + +#include <rtpsession.h> +#include <payloadtype.h> +#include <math.h> +#include <stdlib.h> + +#define JC_BETA 0.03 /*allows a clock slide around 3% */ +#define JC_GAMMA (JC_BETA) + +#include "jitterctl.h" + +void jitter_control_init(JitterControl *ctl, int base_jiitt_time, PayloadType *payload){ + ctl->count=0; + ctl->slide=0; + ctl->jitter=0; + ctl->inter_jitter=0; + ctl->slide=0; + if (base_jiitt_time!=-1) ctl->jitt_comp = base_jiitt_time; + /* convert in timestamp unit: */ + if (payload!=NULL){ + jitter_control_set_payload(ctl,payload); + } + ctl->adapt_jitt_comp_ts=ctl->jitt_comp_ts; + ctl->corrective_slide=0; +} + +void jitter_control_enable_adaptive(JitterControl *ctl, gboolean val){ + ctl->adaptive=val; +} + +void jitter_control_set_payload(JitterControl *ctl, PayloadType *pt){ + ctl->jitt_comp_ts = + (gint) (((double) ctl->jitt_comp / 1000.0) * (pt->clock_rate)); + ctl->corrective_step=(160 * 8000 )/pt->clock_rate; /* This formula got to me after some beers */ + ctl->adapt_jitt_comp_ts=ctl->jitt_comp_ts; +} + + +void jitter_control_dump_stats(JitterControl *ctl){ + g_log("oRTP-stats",G_LOG_LEVEL_MESSAGE,"JitterControl:\n\tslide=%g,jitter=%g,count=%i", + ctl->slide,ctl->jitter, ctl->count); +} + + +/* + The algorithm computes two values: + slide: an average of difference between the expected and the socket-received timestamp + jitter: an average of the absolute value of the difference between socket-received timestamp and slide. + slide is used to make clock-slide detection and correction. + jitter is added to the initial jitt_comp_time value. It compensates bursty packets arrival (packets + not arriving at regular interval ). +*/ +void jitter_control_new_packet(JitterControl *ctl, guint32 packet_ts, guint32 cur_str_ts, gint32 * slide, gint32 *safe_delay){ + int diff=packet_ts - cur_str_ts; + float gap; + int d; + //printf("diff=%g\n",diff); + + ctl->count++; + ctl->slide= (ctl->slide*(1-JC_BETA)) + ((float)diff*JC_BETA); + gap=fabs((float)diff - ctl->slide); + ctl->jitter=(ctl->jitter*(1-JC_GAMMA)) + (gap*JC_GAMMA); + d=diff-ctl->olddiff; + ctl->inter_jitter=ctl->inter_jitter+ (( (float)abs(d) - ctl->inter_jitter)*(1/16.0)); + ctl->olddiff=diff; + if (ctl->adaptive){ + int tmp; + if (ctl->count%50==0) { + /*jitter_control_dump_stats(ctl);*/ + } + tmp=(int)(ctl->slide)-ctl->corrective_slide; + if (tmp>ctl->corrective_step) ctl->corrective_slide+=ctl->corrective_step; + else if (tmp<-ctl->corrective_step) ctl->corrective_slide-=ctl->corrective_step; + /* the following is nearly equivalent, but maybe it consumes more CPU: ?*/ + /*ctl->corrective_slide=(((gint)ctl->slide)/ctl->corrective_step)*ctl->corrective_step;*/ + + ctl->adapt_jitt_comp_ts=MAX(ctl->jitt_comp_ts,ctl->jitter); + + *slide=(gint32)ctl->slide; + *safe_delay=(gint32)ctl->adapt_jitt_comp_ts; + }else { + *slide=0; + *safe_delay=(gint32)ctl->jitt_comp_ts; + } + return ; +} + + +/** + *rtp_session_set_jitter_compensation: + *@session: a RtpSession + *@milisec: the time interval in milisec to be jitter compensed. + * + * Sets the time interval for which packet are buffered instead of being delivered to the + * application. + **/ +void +rtp_session_set_jitter_compensation (RtpSession * session, gint milisec) +{ + PayloadType *payload = rtp_profile_get_payload (session->profile, + session-> + payload_type); + if (payload==NULL){ + g_warning("rtp_session_set_jitter_compensation: cannot set because the payload type is unknown"); + return; + } + jitter_control_init(&session->rtp.jittctl,milisec,payload); +} + +void rtp_session_enable_adaptive_jitter_compensation(RtpSession *session, gboolean val){ + jitter_control_enable_adaptive(&session->rtp.jittctl,val); +} + +gboolean rtp_session_adaptive_jitter_compensation_enabled(RtpSession *session){ + return session->rtp.jittctl.adaptive; +} |