A couple ideas, are they doable?

Discussion of developmental aspects of the MiSTer Project.
ulfrinn
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A couple ideas, are they doable?

Unread post by ulfrinn »

I had a couple ideas for an FPGA, specifically the DE-10 Nano primarily used as a MiSTer. The first idea is to use some kind of an analog to digital converter to digitize RGBs, RGBHV, YPBPR signals and use the FPGA to deinterlace, upscale, and output over HDMI, so the MiSTer can double as an OSSC-like device for use with other consoles.

Another idea I had was outputting video simultaneously over HDMI, and also over USB3.0 or ethernet so that the video could be imported into OBS or other streaming software without the use for a capture card, most of which add some level of noise, and a lot of costs for something that theoretically should be able to do it.

So the idea would be to create an FPGA device that can play old consoles complete lag-free, upscale and convert the video output of original hardware (such as that from a PS2, Dreamcast, etc), and work as its own integrated capture card for livestreaming purposes.

Can this be done? I am certain an ADC chip will be necessary, perhaps a purpose built I/O board to contain it and the video inputs. And the capture/sending video to PC aspect of it is all digital so shouldn't need a lot of external parts to get working?
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BigMac2
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Re: A couple ideas, are they doable?

Unread post by BigMac2 »

Question about transforming the Mister into an OSSC has already been debated many times, doing so needs to reallocate currently used GPIO and add a new IOBoard with analog inputs, from there it’s better have another dedicated project than merge it into Mister.

Now about video over USB, in my understanding of the Cyclone V architecture, the USB and network bus is connected to the HPS which the speed and bandwidth between the HPS and the FPGA within the Cyclone V won't be enough to compress video and sound feed from the FPGA scaler thru USB or network. Even if possible the result would worst be then HDMI who don't use lossy compression.
zakk4223
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Re: A couple ideas, are they doable?

Unread post by zakk4223 »

The first thing is basically the OSSC-Pro (they are using a cyclone V, at least they were last I looked). I know at one point they were talking about having a small add-on pcb for a de-10 to get some of the ossc-pro functionality. I have no idea where that project stands, nor if it would even be feasible to have both that and a 'normal' mister co-exist.

As far as video capture: you CAN get to the video memory via the linux side (see: https://github.com/alanswx/Screenshot_MiSTer)
I guess in theory you could use NDI to send it over the network, but there are real questions if you can sustain 60fps due to cpu and memory bandwidth issues. There's also no access to sound that I know of.

Probably not practically doable
C-R-T
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Re: A couple ideas, are they doable?

Unread post by C-R-T »

There’s another thread like this somewhere where there was a link to a github project where someone had already made an OSSC like thing with the DE10 nano. Not at all related to mister, it is its own thing.
ByteMavericks
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Re: A couple ideas, are they doable?

Unread post by ByteMavericks »

It’s not fpga, but rgbtohdmi makes use of a raspberry pi and cpld to capture digital signals inside a machine before the d2a stage, and it works with up to 12 bit colour (4096 colours, as in the Amiga)

That project is on GitHub and might give some good hints too?
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Newsdee
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Re: A couple ideas, are they doable?

Unread post by Newsdee »

I don't see the point other than trying to save a few bucks. An independent (and dedicated) capture device is really worth it to reduce a lot of hassle.
My device comes up as a camera on Windows so I can easily capture, stream, or use it in Skype/Zoom calls.
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Sorgelig
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Re: A couple ideas, are they doable?

Unread post by Sorgelig »

OSSC-like is possible but it doesn't have to live in the same physical de10-nano as MiSTer. You always can buy second de10-nano for that purpose and create a scaler around it. As mentioned above, it will require add-on board to digitize analog video.
With digital I/O board the second 40pin connector is basically unused which gives opportunity to use digitizer board on that (at least till MiSTer will occupy it) and use the same de10-nano for MiSTer and scaler.
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Re: A couple ideas, are they doable?

Unread post by bazza_12 »

Sorgelig wrote: Sat Apr 03, 2021 6:28 am(at least till MiSTer will occupy it)
oOo have you something in mind?
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Re: A couple ideas, are they doable?

Unread post by Sorgelig »

bazza_12 wrote: Sat Apr 03, 2021 9:58 am
Sorgelig wrote: Sat Apr 03, 2021 6:28 am(at least till MiSTer will occupy it)
oOo have you something in mind?
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