webcam-to-hdmi converter?

[1clue]

Hi,

I want some sort of microcontroller. It needs to:
[list=]
[*]Take video from a 1920x1080 webcam
[*]Push it to an HDMI output.
[*]Should have a decent frame rate, but doesn't need to be excellent.
[*]USB powered would be nice, and auto-on with power.
[*]A USB flash drive storage would be good.
[/list]

This is a reading aid. I'm trying to find a reading solution for my parents. They're both old, pushing 80, neither one can see worth a darn. But they have this big screen TV set.

What I'd like is to clamp the web cam to the top of a TV, pointing downward. When the TV turns on it powers up both the webcam and the microcontroller, the microcontroller boots up and starts pushing video to the HDMI. When the TV turns off the power goes out and the camera and board die of starvation. If they change the source on the TV set it selects the camera setup, and they can use it as a 50" magnifying glass.

I've done a test run with my phone and it works great, they can read and life is good. But the phone is too complicated for them to read, and none of the text is big enough for them to read it so they can't run the phone.

I've shopped all over for a commercially available solution. It's crazy. Cameras these days turn off the camera part as soon as you hook up USB or HDMI to them, and then there's a lot of fiddling to get the camera set up anyway. Webcams don't hook straight up to the TV, it won't work because of no driver and not enough sense in the TV to install one. Security cameras are max 720 lines of resolution and those are way more expensive than I think they should be, on the order of $150 or $200 for a camera that's inferior to a $30 webcam. You look up reading aids and they're talking $1600 for a plain old opaque projector, which is a magnifying glass with a bright light bulb, more for a high-tech solution.

So I'm looking for something, hopefully a step above a Raspberry Pi. It would be neat if it has or can get a 1920x1080 cell phone camera. It needs to be able to be programmed to go straight into camera mode, which I know I can do if it's a Linux kernel. It would be nice if it's fairly cheap.

Anyone have any idea for project boards or small CPUs for this sort of thing?