[BUG] kvsWebrtcClientMasterGstSample ' s video delay is very high compared to audio

[kabosy620]

When I executed below sample app and launch "KVS WebRTC Test Page"'s Viewer,
./kvsWebrtcClientMasterGstSample test_channnel audio-video testsrc

"chrome://webrtc-internals" shows a video latency of about 4 sec. On the other hand, audio latencyis less than 100ms.
（Please refer to the attached image.）

When I set video-only argument , video latency is very law.

when connecting USB camera and remove the testsrc argument, the symptoms were the same.

A similar issue has been posted on stack overflow.
https://stackoverflow.com/questions/72044633/fix-audio-video-sync-on-aws-kinesis-stream-gstreamer-on-rapsberry-pi

Master Device is RPi4 (Raspbian GNU/Linux 10 (buster)

SDK Ver is v1.73

Enabling or disabling TURN had no effect on latency.

Please Confirm.

[SEIDO-JP]

All I can say is that I am in exactly the same situation.

Audio+Video stream => "jitterBufferDelay" for audio is constant at ~40ms, "jitterBufferDelay" for video keeps getting bigger at about +300ms/5minutes.
Video only stream => "jitterBufferDelay" for video stream is constant 40ms (and delay is almost not noticeable).

[disa6302]

Can you try pulling in this change in the samples and see if it solves the issue?

#1525

[kabosy620]

Thank you for your reply

Following #1525, I changed the code in sample.h as below.

before #define DEFAULT_FPS_VALUE 25
after #define DEFAULT_FPS_VALUE 30
(My USB webcam doesn't support 25fps, so I changed DEFAULT_FPS_VALUE not gstreamer's command line.)

And, My issue's solved! (Video latency is around 60ms.)

Thank you for your support.