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Stream Android Screen to PC

walfish3d

Lurker
Nov 22, 2010
2
0
Hello people this is my first post here *wave*

I know there is already a thread with exactly the same title, but not exactly the content i need.

What i would like to do with my android phone is to stream everything which is displayed on my phone to my pc. either via wlan or usb, i dont care (whatever works). I am NOT searching for an app which lets me control my android from my pc. I would only like to see on my computer screen whatever is shown on my android phone. I'd say my android should behave like an expansive webcam :).

The only 'app' I found so far which is capable of this is 'androidscreencast' androidscreencast - Project Hosting on Google Code
It's a nice application and it basically does what I described above, but with 3-4 fps it just performs way too bad.

Any pointers?
 
thanks for your answers, unfortunately not what I hoped for :)
can someone provide a technical explanation why this stuff performs so bad? What is the bottleneck?


I suspect that the bottle neck is in the app needing to take snapshots, package them, and then send them across the network. I assume this is how it works, but I am not sure. Maybe it does something else.

When I use a screen capture program, the images are all 500K on average. 4FPS means capturing 2MB worth of data, and then sending that over a communication medium.

2MBytes = 16Mbits

I don't know much about HD encoding. I do know that H264 is pretty good at compression, but I haven't found concrete numbers on google yet to tell me how much bandwidth it needs.

I did see a mention of 8Mbps for HD video using H264 (MPEG-2 would require 15Mbps).

So with HD compression, we can get 30fps of HD content in 8Mbps of bandwidth...but when taking snapshots which become jpgs, we can't even come close to 30fps in 8Mbps. As shown above, 4 screenshots requires 16Mbps.

I suspect that the app would have to capture the video before the screen displays it. Perhaps it can grab the stream, encode it, and then send it on it's way. HDMI ports should be used for this sort of thing IMHO, and on some phones, media content is routed over HDMI, but not the phone's desktop. I wonder why there is a limitation there.
 
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. . .and on some phones, media content is routed over HDMI, but not the phone's desktop. I wonder why there is a limitation there.

My Galaxy S II hooked up to my HDTV, which displays everything as a mirror display, at a high framerate, launcher interactions and all. My coworker's older HTC Evo 4G could only route video. My guess is all phones with MHL support routes everything now, so if your pc display has an hdmi port youre good to go, unless you specifically wanted it to run in the operating system and not just the display, which probably will only work at low framerates for now
 
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I came here with the same question. I want to walk around a room, tablet or phone in hand (I don't care which), running a presentation through a prjector. If you can mirror a TV or projector via an HDMI cable, then perhaps what we want to do can be done as long as you have two Android devices. I have phone and a tablet, and I understand there are apps that let one control the other. If that's true, perhaps I could connect either one to a projector via HDMI and operate it from the other while walking the room. Thoughts?
 
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