Commit 44788e00 authored by Håvard Graff's avatar Håvard Graff

rtpjitterbuffer: make sure not to drop packets based on skew

One of the jitterbuffers functions is to try and make sense of weird
network behavior.

It is quite unhelpful for the jitterbuffer to start dropping packets
itself when what you are trying to achieve is better network resilience.

In the case of a skew, this could often mean the sender has restarted
in some fashion, and then dropping the very first buffer of this "new"
stream could often mean missing valuable information, like in the case
of video and I-frames.

This patch simply reverts back to the old behavior, prior to gstreamer/gst-plugins-good@8d955fc3
and includes the simplest test I could write to demonstrate the behavior,
where a single packet arrives "perfectly", then a 50ms gap happens,
and then two more packets arrive in perfect order after that.

# Conflicts:
#	tests/check/elements/rtpjitterbuffer.c
parent 8e1c224f
Pipeline #71879 failed with stages
in 69 minutes and 57 seconds
......@@ -955,8 +955,8 @@ rtp_jitter_buffer_calculate_pts (RTPJitterBuffer * jbuf, GstClockTime dts,
GST_TIME_FORMAT ", reset jitterbuffer and discard", GST_TIME_ARGS (pts),
jbuf->delay, GST_TIME_ARGS (dts));
rtp_jitter_buffer_reset_skew (jbuf);
goto done;
rtp_jitter_buffer_resync (jbuf, dts, gstrtptime, ext_rtptime, TRUE);
pts = dts;
jbuf->prev_out_time = pts;
......@@ -2729,6 +2729,38 @@ GST_START_TEST (test_rtx_does_not_affect_pts_calculation)
GST_START_TEST (test_dont_drop_packet_based_on_skew)
GstHarness *h = gst_harness_new ("rtpjitterbuffer");
guint base_seqnum;
GstClockTime now;
guint i;
/* set up a deterministic state and take the time on the clock */
g_object_set (h->element, "do-retransmission", TRUE, "do-lost", TRUE, NULL);
base_seqnum = construct_deterministic_initial_state (h, 20);
now = gst_clock_get_time (GST_ELEMENT_CLOCK (h->element));
/* and after a delay of 50ms... */
now += GST_MSECOND * 50;
gst_test_clock_set_time (GST_TEST_CLOCK (GST_ELEMENT_CLOCK (h->element)), now);
/* ..two more buffers arrive in perfect order */
for (i = 0; i < 2; i++) {
gst_harness_push (h, generate_test_buffer_full (now + i * GST_MSECOND * 20,
base_seqnum + i, (base_seqnum + i) * TEST_RTP_TS_DURATION));
/* verify we did not drop any of them */
for (i = 0; i < 2; i++) {
gst_buffer_unref (gst_harness_pull (h));
gst_harness_teardown (h);
GST_START_TEST (test_timer_queue_set_timer)
RtpTimerQueue *queue = rtp_timer_queue_new ();
......@@ -3364,6 +3396,7 @@ rtpjitterbuffer_suite (void)
tcase_add_test (tc_chain, test_minor_reorder_does_not_skew);
tcase_add_loop_test (tc_chain, test_rtx_does_not_affect_pts_calculation, 0,
G_N_ELEMENTS (rtx_does_not_affect_pts_calculation_input));
tcase_add_test (tc_chain, test_dont_drop_packet_based_on_skew);
tcase_add_test (tc_chain, test_deadline_ts_offset);
tcase_add_test (tc_chain, test_big_gap_seqnum);
Markdown is supported
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment