High latency (10-15s) on Android web browser when viewing RTSP streams

[Hokoha Team]

Hello,

We are developping a web application that uses Janus to display RTSP streams from cameras.

It's working well on Desktop browsers (Edge, Firefox, Chrome), on iOS devices (Safari, Chrome ...) but on Android devices, we face a high latency (10-15 seconds nearly everytime) when starting to read RTSP streams.

Janus logs show that "remote track muted" and then it displays "Removing remote track". After a while (10 seconds), the message "Remote track flowing again" happens and the stream is displayed correctly.

We use H264 codec with profile-level-id=42e01f ...

It does not seem to be linked to the devices, nor to browsers ...

We check our network and everything seems ok ... except this latency of RTSP streams on Android !

I am not sure that janus is involved but maybe some of you have met this issue ... and solved it ?

Many thanks by advance for every ideas !!

Best regards,

Laurent C.

[John Hassell]

I have seen something similar when my generated video stream had non-perfect video frame timestamps. Do you have a component like gstreamer's videorate for your camera's video pipeline?

[Hokoha Team]

Thanks for your reply but no : cameras use their own streaming solution and I don't have access to a lot of settings ... unfortunaletly ...

Best regards,

Laurent C.

[Lorenzo Miniero]

If the browser doesn't get a keyframe right away, it will need to wait until the camera sends one to show something.

L.

[Hokoha Team]

Many thanks ! I forward this assumption to camera manufacturer (Hikvision) ...

But I wonder why this would impact only Android devices ? Is there any known weakness of this system regarding RTSP frames and keyframes ?

Best regards,

Laurent C.