> FPGAs' in our machines that you could just use flash to the newest codec
They're called GPUs... They're ASICs rather than FPGAs, but it's easy to update the driver software to handle new video codecs. The difficulty is motivating GPU manufacturers to do so... They'd rather sell you a new one with newer codec support as a feature.
A lot of the GPUs have fixed function hardware to accelerate parts of encode/decode. If the new codec is compatible, sure.
But often a new codec requires decoders to know how to work with new things that the fixed function hardware likely can't do.
Encoding might actually be different. If your encoder hardware can only do fixed block sizes, and can only detect some types of motion, a driver change might be able to package it up as the new codec. Probably not a lot of benefit, other than ticking a box... but might be useful sometimes. Especially if you say offload motion detection, but the new codec needs different arithmetic encoding, you'd need to use cpu (or general purpose gpu) to do the arithmetic encoding and presumably get a size saving over the old codec.
They’re programmable parallel compute units, and as such pretty much the conceptual opposite of ASICs.
The main point of having ASICs for video codecs these days is efficiency, not being able to real-time decode a stream at all (as even many embedded CPUs can do that at this point).
They're called GPUs... They're ASICs rather than FPGAs, but it's easy to update the driver software to handle new video codecs. The difficulty is motivating GPU manufacturers to do so... They'd rather sell you a new one with newer codec support as a feature.