Screen share quality is poor when use app on IOS or android

We build a our own app by using jitsi sdk.
And we found the screen quality is poor in ios/android app when the PC shares screen.

Any suggestions are greatly appreciated.

We have found it’s ok when we use the jitsi app provided by the official.
But when we use the app build by ourself using jitsi android sdk, the quality is poor.
So, we want to know the version of jitsi sdk using by the official app( org.jitsi.meet_215000.apk).
Any help is greatly appreciated

Or someone could tell me the git of offical jitsi android app,
we want to get it as reference.