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Add debug message calculating packet arrival and disperal times

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This commit is contained in:
Mike Brady
2016-02-29 15:06:38 +00:00
parent e9966089b8
commit c235dc3031
1 changed files with 35 additions and 2 deletions
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rtp.c
+35 -2
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@@ -29,6 +29,7 @@
#include <signal.h>
#include <unistd.h>
#include <memory.h>
#include <math.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
@@ -99,9 +100,41 @@ void *rtp_audio_receiver(void *arg) {
int32_t last_seqno = -1;
uint8_t packet[2048], *pktp;
uint64_t time_of_previous_packet_fp = 0;
float longest_packet_time_interval_us = 0.0;
// mean and variance calculations from "online_variance" algorithm at https://en.wikipedia.org/wiki/Algorithms_for_calculating_variance#Online_algorithm
int32_t stat_n = 0;
float stat_mean = 0.0;
float stat_M2 = 0.0;
ssize_t nread;
while (itr->please_stop==0) {
nread = recv(audio_socket, packet, sizeof(packet), 0);
uint64_t local_time_now_fp = get_absolute_time_in_fp();
if (time_of_previous_packet_fp) {
float time_interval_us = (((local_time_now_fp - time_of_previous_packet_fp)*1000000)>>32)*1.0;
time_of_previous_packet_fp = local_time_now_fp;
if (time_interval_us>longest_packet_time_interval_us)
longest_packet_time_interval_us=time_interval_us;
stat_n+=1;
float stat_delta = time_interval_us - stat_mean;
stat_mean += stat_delta/stat_n;
stat_M2 += stat_delta*(time_interval_us - stat_mean);
if (stat_n % 2500 == 0) {
debug(2,"Packet reception intervals: mean, standard deviation and max for the last 2,500 packets in microseconds: %10.1f, %10.1f, %10.1f.",stat_mean, sqrtf(stat_M2 / (stat_n-1)),longest_packet_time_interval_us);
stat_n = 0;
stat_mean = 0.0;
stat_M2 = 0.0;
time_of_previous_packet_fp = 0;
longest_packet_time_interval_us = 0.0;
}
} else {
time_of_previous_packet_fp = local_time_now_fp;
}
if (nread < 0)
break;
@@ -121,7 +154,7 @@ void *rtp_audio_receiver(void *arg) {
else {
last_seqno = (last_seqno + 1) & 0xffff;
if (seqno != last_seqno)
debug(2, "RTP: Packets out of sequence: expected: %d, got %d.", last_seqno, seqno);
debug(3, "RTP: Packets out of sequence: expected: %d, got %d.", last_seqno, seqno);
last_seqno = seqno; // reset warning...
}
uint32_t timestamp = ntohl(*(unsigned long *)(pktp + 4));
@@ -701,7 +734,7 @@ void rtp_shutdown(void) {
void rtp_request_resend(seq_t first, uint32_t count) {
if (running) {
//if (!request_sent) {
debug(2, "requesting resend of %d packets starting at %u.", count, first);
debug(3, "requesting resend of %d packets starting at %u.", count, first);
// request_sent = 1;
//}