Android Libstreaming: How to improve video quality (Testing in Nexus 5)

Question

I am developing an android application. I am sending stream (audio+video) from Mobile to Wowza. I am using Libstreaming library for streaming. The video quality is too bad. How can we improve it (atleast some text should be readable.) In my code if you see I have commented the video quality (bad with mentioned parameters) method. If i uncomment it, It shows the green cover over the video screen.

And also, is it possible to make quality device independent ?

My streaming code is:

mSession = SessionBuilder
            .getInstance()
            .setContext(getApplicationContext())
            .setAudioEncoder(SessionBuilder.AUDIO_AAC)
            .setAudioQuality(new AudioQuality(8000, 16000))
            .setVideoEncoder(SessionBuilder.VIDEO_H264)
            //.setVideoQuality(new VideoQuality(352, 288, 30, 300000))
            .setCamera(CameraInfo.CAMERA_FACING_BACK)
            .setSurfaceView(mSurfaceView).setPreviewOrientation(0)
            .setCallback(this).build();

Thanks.