How to reduce glass to glass latency?

[renaudcerrato]

I'm receiving a raw H264 stream by TCP (with PTS informations) using a custom Extractor, feeding it to an H264Reader, and I'm looking to achieve the lowest latency. The stream is coming from the local network only, and I may be considering switching to UDP at some point if required.

For an evaluation purpose I've run both the streamer and the player on the same device (in 2 different process), the streamer actually streams the current screen. I'm using a zeroified load control:

val loadControl = DefaultLoadControl.Builder()
            .setBufferDurationsMs(0, 0, 0, 0)
            .setPrioritizeTimeOverSizeThresholds(true)
            .build()

I've put a running timer at the top of screen, and the best I can achieve is roughly 250ms(800x390@1Mbps) which sounds quite a lot:

Is there anything I could look at to improve the latency ? I'm sure there's a lot of room for improvements and I may be missing something.

Related to #1179

[tonihei]

As you say, this is more or less a duplicate of #1179, which I just converted to a feature request.