diff options
| -rw-r--r-- | main/rtp_engine.c | 2 | ||||
| -rw-r--r-- | res/res_rtp_asterisk.c | 49 |
2 files changed, 42 insertions, 9 deletions
diff --git a/main/rtp_engine.c b/main/rtp_engine.c index 051253103..5c7b7a07b 100644 --- a/main/rtp_engine.c +++ b/main/rtp_engine.c @@ -1987,7 +1987,7 @@ static struct ast_manager_event_blob *rtcp_report_to_ami(struct stasis_message * if (type == AST_RTP_RTCP_SR) { ast_str_append(&packet_string, 0, "SentNTP: %lu.%06lu\r\n", (unsigned long)payload->report->sender_information.ntp_timestamp.tv_sec, - (unsigned long)payload->report->sender_information.ntp_timestamp.tv_usec * 4096); + (unsigned long)payload->report->sender_information.ntp_timestamp.tv_usec); ast_str_append(&packet_string, 0, "SentRTP: %u\r\n", payload->report->sender_information.rtp_timestamp); ast_str_append(&packet_string, 0, "SentPackets: %u\r\n", diff --git a/res/res_rtp_asterisk.c b/res/res_rtp_asterisk.c index 75bace26b..b8cb10b30 100644 --- a/res/res_rtp_asterisk.c +++ b/res/res_rtp_asterisk.c @@ -3086,7 +3086,26 @@ static void timeval2ntp(struct timeval tv, unsigned int *msw, unsigned int *lsw) unsigned int sec, usec, frac; sec = tv.tv_sec + 2208988800u; /* Sec between 1900 and 1970 */ usec = tv.tv_usec; - frac = (usec << 12) + (usec << 8) - ((usec * 3650) >> 6); + /* + * Convert usec to 0.32 bit fixed point without overflow. + * + * = usec * 2^32 / 10^6 + * = usec * 2^32 / (2^6 * 5^6) + * = usec * 2^26 / 5^6 + * + * The usec value needs 20 bits to represent 999999 usec. So + * splitting the 2^26 to get the most precision using 32 bit + * values gives: + * + * = ((usec * 2^12) / 5^6) * 2^14 + * + * Splitting the division into two stages preserves all the + * available significant bits of usec over doing the division + * all at once. + * + * = ((((usec * 2^12) / 5^3) * 2^7) / 5^3) * 2^7 + */ + frac = ((((usec << 12) / 125) << 7) / 125) << 7; *msw = sec; *lsw = frac; } @@ -3094,7 +3113,8 @@ static void timeval2ntp(struct timeval tv, unsigned int *msw, unsigned int *lsw) static void ntp2timeval(unsigned int msw, unsigned int lsw, struct timeval *tv) { tv->tv_sec = msw - 2208988800u; - tv->tv_usec = ((lsw << 6) / 3650) - (lsw >> 12) - (lsw >> 8); + /* Reverse the sequence in timeval2ntp() */ + tv->tv_usec = ((((lsw >> 7) * 125) >> 7) * 125) >> 12; } static void calculate_lost_packet_statistics(struct ast_rtp *rtp, @@ -3279,9 +3299,9 @@ static int ast_rtcp_write_report(struct ast_rtp_instance *instance, int sr) ast_sockaddr_stringify(&remote_address), ice ? " (via ICE)" : ""); ast_verbose(" Our SSRC: %u\n", rtcp_report->ssrc); if (sr) { - ast_verbose(" Sent(NTP): %u.%010u\n", + ast_verbose(" Sent(NTP): %u.%06u\n", (unsigned int)rtcp_report->sender_information.ntp_timestamp.tv_sec, - (unsigned int)rtcp_report->sender_information.ntp_timestamp.tv_usec * 4096); + (unsigned int)rtcp_report->sender_information.ntp_timestamp.tv_usec); ast_verbose(" Sent(RTP): %u\n", rtcp_report->sender_information.rtp_timestamp); ast_verbose(" Sent packets: %u\n", rtcp_report->sender_information.packet_count); ast_verbose(" Sent octets: %u\n", rtcp_report->sender_information.octet_count); @@ -4020,9 +4040,22 @@ static int update_rtt_stats(struct ast_rtp *rtp, unsigned int lsr, unsigned int lsr_a = ((msw & 0x0000ffff) << 16) | ((lsw & 0xffff0000) >> 16); rtt = lsr_a - lsr - dlsr; rtt_msw = (rtt & 0xffff0000) >> 16; - rtt_lsw = (rtt & 0x0000ffff) << 16; + rtt_lsw = (rtt & 0x0000ffff); rtt_tv.tv_sec = rtt_msw; - rtt_tv.tv_usec = ((rtt_lsw << 6) / 3650) - (rtt_lsw >> 12) - (rtt_lsw >> 8); + /* + * Convert 16.16 fixed point rtt_lsw to usec without + * overflow. + * + * = rtt_lsw * 10^6 / 2^16 + * = rtt_lsw * (2^6 * 5^6) / 2^16 + * = rtt_lsw * 5^6 / 2^10 + * + * The rtt_lsw value is in 16.16 fixed point format and 5^6 + * requires 14 bits to represent. We have enough space to + * directly do the conversion because there is no integer + * component in rtt_lsw. + */ + rtt_tv.tv_usec = (rtt_lsw * 15625) >> 10; rtp->rtcp->rtt = (double)rtt_tv.tv_sec + ((double)rtt_tv.tv_usec / 1000000); if (lsr_a - dlsr < lsr) { return 1; @@ -4218,9 +4251,9 @@ static struct ast_frame *ast_rtcp_read(struct ast_rtp_instance *instance) &rtcp_report->sender_information.ntp_timestamp); rtcp_report->sender_information.rtp_timestamp = ntohl(rtcpheader[i + 2]); if (rtcp_debug_test_addr(&addr)) { - ast_verbose("NTP timestamp: %u.%010u\n", + ast_verbose("NTP timestamp: %u.%06u\n", (unsigned int)rtcp_report->sender_information.ntp_timestamp.tv_sec, - (unsigned int)rtcp_report->sender_information.ntp_timestamp.tv_usec * 4096); + (unsigned int)rtcp_report->sender_information.ntp_timestamp.tv_usec); ast_verbose("RTP timestamp: %u\n", rtcp_report->sender_information.rtp_timestamp); ast_verbose("SPC: %u\tSOC: %u\n", rtcp_report->sender_information.packet_count, |