in RtpPacketizer add support for first packet reduction length
Bug: webrtc:9680
Change-Id: I68580a8a44cbbf932ed0b2448b31169b26df5044
Reviewed-on: https://webrtc-review.googlesource.com/98005
Commit-Queue: Danil Chapovalov <danilchap@webrtc.org>
Reviewed-by: Ilya Nikolaevskiy <ilnik@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#24584}diff --git a/modules/rtp_rtcp/source/rtp_format.cc b/modules/rtp_rtcp/source/rtp_format.cc
index bddec73..030236c 100644
--- a/modules/rtp_rtcp/source/rtp_format.cc
+++ b/modules/rtp_rtcp/source/rtp_format.cc
@@ -65,11 +65,15 @@
std::vector<size_t> RtpPacketizer::SplitAboutEqually(
size_t payload_len,
const PayloadSizeLimits& limits) {
+ RTC_CHECK_GT(limits.max_payload_len, limits.first_packet_reduction_len);
RTC_CHECK_GT(limits.max_payload_len, limits.last_packet_reduction_len);
- // Last packet can be smaller. Pretend that it's the same size, but we must
- // write more payload to it.
- size_t total_bytes = payload_len + limits.last_packet_reduction_len;
+ // First and last packet of the frame can be smaller. Pretend that it's
+ // the same size, but we must write more payload to it.
+ // Assume frame fits in single packet if packet has extra space for sum
+ // of first and last packets reductions.
+ size_t total_bytes = payload_len + limits.first_packet_reduction_len +
+ limits.last_packet_reduction_len;
// Integer divisions with rounding up.
size_t num_packets_left =
(total_bytes + limits.max_payload_len - 1) / limits.max_payload_len;
@@ -79,12 +83,19 @@
std::vector<size_t> result;
result.reserve(num_packets_left);
+ bool first_packet = true;
while (remaining_data > 0) {
// Last num_larger_packets are 1 byte wider than the rest. Increase
// per-packet payload size when needed.
if (num_packets_left == num_larger_packets)
++bytes_per_packet;
size_t current_packet_bytes = bytes_per_packet;
+ if (first_packet) {
+ if (current_packet_bytes > limits.first_packet_reduction_len + 1)
+ current_packet_bytes -= limits.first_packet_reduction_len;
+ else
+ current_packet_bytes = 1;
+ }
if (current_packet_bytes > remaining_data) {
current_packet_bytes = remaining_data;
}
@@ -93,11 +104,11 @@
if (num_packets_left == 2 && current_packet_bytes == remaining_data) {
--current_packet_bytes;
}
-
result.push_back(current_packet_bytes);
remaining_data -= current_packet_bytes;
--num_packets_left;
+ first_packet = false;
}
return result;