Change aggregated fraction loss to be calculated from the cumulative loss and extended sequence number diff between the current and the last report block of two get stats calls.
Previously it was derived from the fraction loss of the current report (which could be based on a received report block in between two get stats calls).
R=stefan@webrtc.org
Review URL: https://webrtc-codereview.appspot.com/36399004
git-svn-id: http://webrtc.googlecode.com/svn/trunk@7928 4adac7df-926f-26a2-2b94-8c16560cd09d
diff --git a/webrtc/video_engine/vie_channel.cc b/webrtc/video_engine/vie_channel.cc
index fffb970..67ec6b8 100644
--- a/webrtc/video_engine/vie_channel.cc
+++ b/webrtc/video_engine/vie_channel.cc
@@ -47,8 +47,8 @@
RTCPReportBlock AggregateReportBlocks(
const std::vector<RTCPReportBlock>& report_blocks,
std::map<uint32_t, RTCPReportBlock>* prev_report_blocks) {
- int fraction_lost_sum = 0;
- int fl_seq_num_sum = 0;
+ int num_sequence_numbers = 0;
+ int num_lost_sequence_numbers = 0;
int jitter_sum = 0;
int number_of_report_blocks = 0;
RTCPReportBlock aggregate;
@@ -63,18 +63,20 @@
// weight for it.
int seq_num_diff = report_block->extendedHighSeqNum -
prev_report_block->second.extendedHighSeqNum;
- if (seq_num_diff > 0) {
- fraction_lost_sum += report_block->fractionLost * seq_num_diff;
- fl_seq_num_sum += seq_num_diff;
+ int cum_loss_diff = report_block->cumulativeLost -
+ prev_report_block->second.cumulativeLost;
+ if (seq_num_diff >= 0 && cum_loss_diff >= 0) {
+ num_sequence_numbers += seq_num_diff;
+ num_lost_sequence_numbers += cum_loss_diff;
}
}
jitter_sum += report_block->jitter;
++number_of_report_blocks;
(*prev_report_blocks)[report_block->sourceSSRC] = *report_block;
}
- if (fl_seq_num_sum > 0) {
- aggregate.fractionLost =
- (fraction_lost_sum + fl_seq_num_sum / 2) / fl_seq_num_sum;
+ if (num_sequence_numbers > 0) {
+ aggregate.fractionLost = ((num_lost_sequence_numbers * 255) +
+ (num_sequence_numbers / 2)) / num_sequence_numbers;
}
if (number_of_report_blocks > 0) {
aggregate.jitter =
