reverse engineer the CD32 FMV card.... ?

[psxphill]

afaik you can't DMA into chipram?

Why do you think that? Lots of zorro2 cards can DMA into chip ram, it's not ideal but it works.

Video CD are 1.44 Mbps. AGA has enough bandwidth, not so sure about ECS.

[psxphill]

That's 1.44Mbps of compressed MPEG stream. The decoded stream is ~61Mbits/s for NTSC.

Ok, I got missed where the conversation went from FMV to some new device.

Supposedly VCD is 352x240x30hz, so 8 bit planes (either HAM8 or 256 color) would be 2,534,400 bytes a second. Which should be doable on a low res AGA screen.

[psxphill]

but looking at this with a bit of a wider view, i suspect we've kinda jumped the relevance of a separate mpeg card - given with the CPU options that are currently and potentially available.

Sure, although that doesn't automatically make it a bad idea to reverse engineer the CD32 FMV card.

You could re-implement it in an FPGA for lolz.

[psxphill]

i think the 3DO was the first console machine with enough grunt to layer the video feed from the MPEG decoder into display ram - even usable as texture map in 3D space, or am i going to far there?

Apparently there is a different 3do video cd adapter for NTSC & PAL, so it's possible they worked the same as the CD32. Normal game video is done differently.

Even if it did, I don't think it supported 24 bit textures.

but i like the idea even more of having it write back into framebuffer ram, be it chip or zorro so the amiga can actually do something with the graphics data itself; Instead of being just a glorified control system for a dedicated decoder/framebuffer combo - even if it was video-mixed/genlocked allowing a single display...

Sure and if you could have gone back to 1986 and stop them wasting money on AAA and start AGA sooner so that it could have had chunky 256 and 24 bit video, so that when the CD32 came it could dma the graphics in and actually display them then maybe it would have happened. They may have had to develop their own custom MPEG decoder chips though & commodore had basically no money when doing the CD32