OSSC Pro

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marqs
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Re: OSSC Pro

Post by marqs »

kitty666cats wrote: Sun Dec 15, 2024 6:22 am RE: shmupsrocks’ question

The analog out board uses an ADV7125 which is a very good DAC chip. The RetroTink Ultimate used it & the new MiSTer 24bit analog boards use it.

I’ve never seen any commercial HDMI to VGAs that use it - it’s extremely color-accurate, though. There’s also the ADV7123 chip which is 30bit instead of 24bit, but that’s pretty redundant for retro games. It’s cheaper, AFAIK, so I don’t see any reason *not* to use it, unless it’s not as easy to deal with
The main challenge with ADV7125/ADV7123 is availability which is hit & miss. For existing extra AV out boards -140 (MHz) version was used, but right now the 330MHz version seems to have better stock & price. That would be naturally better (especially for upcoming fw which has 2048x1536 preset) but the situation could change again in few months. Stockpiling would be the only way to ensure them for next batch, but also risky considering these boards are niche of a niche.

The upcoming fw will also add support for 1920x1440_60 inputs (both via analog & digital) and RF input (legacy AV board) which is currently in testing.
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Re: OSSC Pro

Post by shmupsrocks »

kitty666cats wrote: Sun Dec 15, 2024 6:22 am RE: shmupsrocks’ question

The analog out board uses an ADV7125 which is a very good DAC chip. The RetroTink Ultimate used it & the new MiSTer 24bit analog boards use it.

I’ve never seen any commercial HDMI to VGAs that use it - it’s extremely color-accurate, though. There’s also the ADV7123 chip which is 30bit instead of 24bit, but that’s pretty redundant for retro games. It’s cheaper, AFAIK, so I don’t see any reason *not* to use it, unless it’s not as easy to deal with
The Imagenics CRO-DAC11 has an ADV7123:

https://imagenics.co.jp/products/cro-dac11/
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Re: OSSC Pro

Post by SavagePencil »

shmupsrocks wrote: Fri Jan 03, 2025 1:06 pm
The Imagenics CRO-DAC11 has an ADV7123:

https://imagenics.co.jp/products/cro-dac11/
…and costs > $500
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GK6475
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Re: OSSC Pro

Post by GK6475 »

Would it be possible to have 480p signals line multiplied 4x into a 2560x1920 output? This would allow for the best full-screen quailty on TVs like LG OLEDs which have low latency scaling, and will accept odd resolutions like this. So far I haven't been able to configure this resolution to work through the advanced timings, using 2560x1440 as a base won't work past 1800 or so lines for some reason. Also, I don't know if the OSSC Pro is capable of it, but would it be possible to have 640x480 anamorphic content be horizontally scaled 6x into 3840 and have the verticals scaled 4x into 1920? Assuming that the display is using vertical scaling to fill the screen, this would be best for widescreen 480p content on capable displays.
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marqs
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Re: OSSC Pro

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GK6475 wrote: Sat Jan 04, 2025 7:49 pm Would it be possible to have 480p signals line multiplied 4x into a 2560x1920 output? This would allow for the best full-screen quailty on TVs like LG OLEDs which have low latency scaling, and will accept odd resolutions like this. So far I haven't been able to configure this resolution to work through the advanced timings, using 2560x1440 as a base won't work past 1800 or so lines for some reason. Also, I don't know if the OSSC Pro is capable of it, but would it be possible to have 640x480 anamorphic content be horizontally scaled 6x into 3840 and have the verticals scaled 4x into 1920? Assuming that the display is using vertical scaling to fill the screen, this would be best for widescreen 480p content on capable displays.
You are simply asking too much from the HW. FPGA fabric and IO run only up to ~300MHz, and HDMI transmitter up to ~400MHz. Both these numbers are already way beyond their respective official specs.
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Re: OSSC Pro

Post by GK6475 »

marqs wrote: Sat Jan 04, 2025 11:08 pm
GK6475 wrote: Sat Jan 04, 2025 7:49 pm Would it be possible to have 480p signals line multiplied 4x into a 2560x1920 output? This would allow for the best full-screen quailty on TVs like LG OLEDs which have low latency scaling, and will accept odd resolutions like this. So far I haven't been able to configure this resolution to work through the advanced timings, using 2560x1440 as a base won't work past 1800 or so lines for some reason. Also, I don't know if the OSSC Pro is capable of it, but would it be possible to have 640x480 anamorphic content be horizontally scaled 6x into 3840 and have the verticals scaled 4x into 1920? Assuming that the display is using vertical scaling to fill the screen, this would be best for widescreen 480p content on capable displays.
You are simply asking too much from the HW. FPGA fabric and IO run only up to ~300MHz, and HDMI transmitter up to ~400MHz. Both these numbers are already way beyond their respective official specs.
So, how is 2880x2160 possible? If that works, then surely 2560x1920 would work as well?
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marqs
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Re: OSSC Pro

Post by marqs »

GK6475 wrote: Sun Jan 05, 2025 2:12 am So, how is 2880x2160 possible? If that works, then surely 2560x1920 would work as well?
Inside FPGA it's processed as 1440x2160, then horizontally doubled by the HDMI transmitter because of the limitations mentioned. For 4:3 480p content processing at 1280x1920 in a similar manner should be possible.
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Re: OSSC Pro

Post by GK6475 »

marqs wrote: Sun Jan 05, 2025 10:14 am
GK6475 wrote: Sun Jan 05, 2025 2:12 am So, how is 2880x2160 possible? If that works, then surely 2560x1920 would work as well?
Inside FPGA it's processed as 1440x2160, then horizontally doubled by the HDMI transmitter because of the limitations mentioned. For 4:3 480p content processing at 1280x1920 in a similar manner should be possible.
Yeah, that would work great, I'd love to see that implemented at some point. Is 1920x1920 into 3840x1920 possible as well, for anamorphic 640x480 content? That might be pushing it a bit, unless 1280x1920 was multiplied horizontally by 3, then maybe it could work?
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marqs
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Re: OSSC Pro

Post by marqs »

GK6475 wrote: Sun Jan 05, 2025 6:27 pm
marqs wrote: Sun Jan 05, 2025 10:14 am
GK6475 wrote: Sun Jan 05, 2025 2:12 am So, how is 2880x2160 possible? If that works, then surely 2560x1920 would work as well?
Inside FPGA it's processed as 1440x2160, then horizontally doubled by the HDMI transmitter because of the limitations mentioned. For 4:3 480p content processing at 1280x1920 in a similar manner should be possible.
Yeah, that would work great, I'd love to see that implemented at some point. Is 1920x1920 into 3840x1920 possible as well, for anamorphic 640x480 content? That might be pushing it a bit, unless 1280x1920 was multiplied horizontally by 3, then maybe it could work?
1920x1920@60Hz is around 243MHz (1.1x1920x1920x60Hz) if you budget 10% for blanking to ensure audio can be included in the stream. While that still can be processed on FPGA, doubling that on HDMI transmitter exceeds its limits. With generic sampling you could get somewhere around 3200x1920 output which the TV would need to scale to 16:9. Probably would not end up looking much better compared to TV scaling 2560x1920 output (which is compatible with optimized timings).
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GK6475
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Re: OSSC Pro

Post by GK6475 »

:D
marqs wrote: Sun Jan 05, 2025 9:02 pm
GK6475 wrote: Sun Jan 05, 2025 6:27 pm
marqs wrote: Sun Jan 05, 2025 10:14 am Inside FPGA it's processed as 1440x2160, then horizontally doubled by the HDMI transmitter because of the limitations mentioned. For 4:3 480p content processing at 1280x1920 in a similar manner should be possible.
Yeah, that would work great, I'd love to see that implemented at some point. Is 1920x1920 into 3840x1920 possible as well, for anamorphic 640x480 content? That might be pushing it a bit, unless 1280x1920 was multiplied horizontally by 3, then maybe it could work?
1920x1920@60Hz is around 243MHz (1.1x1920x1920x60Hz) if you budget 10% for blanking to ensure audio can be included in the stream. While that still can be processed on FPGA, doubling that on HDMI transmitter exceeds its limits. With generic sampling you could get somewhere around 3200x1920 output which the TV would need to scale to 16:9. Probably would not end up looking much better compared to TV scaling 2560x1920 output (which is compatible with optimized timings).
Ok, 2560x1920 would probably look good enough anyhow, thanks for the info. I imagine it wouldn't be that difficult to implement, maybe in the next firmware update?
Last edited by GK6475 on Thu Jan 09, 2025 7:22 pm, edited 2 times in total.
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Re: OSSC Pro

Post by WasherFace »

Is there any progress to make the scaler mode have less lag?
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Re: OSSC Pro

Post by spmbx »

Any idea when the extra AV out boards will be in stock again at VGP ?
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marqs
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Re: OSSC Pro

Post by marqs »

WasherFace wrote: Thu Jan 09, 2025 2:39 am Is there any progress to make the scaler mode have less lag?
It's listed in wiki under planned improvements alongside rotation, but without ETA. At the moment there are no other developers so it's easier to focus on smaller changes and bug fixing.

spmbx wrote: Thu Jan 09, 2025 7:02 am Any idea when the extra AV out boards will be in stock again at VGP ?
Latest estimate was early February. However, they were just restocked on Stone Age Gamer and available from there.
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Re: OSSC Pro

Post by orange808 »

My apologies, I've fallen behind. What's the status of the machine? I'm still hoping to drop the OSSC Pro in front of my 15kHz CRTs and forget about it.

Is there a planned unit with the analog option preinstalled inside a custom case or a case option for the analog board?

Latency improvements will be welcome. Besides the analog extension case, that's the other reason I haven't purchased a machine yet.

I may have already asked this; will there be flicker filter adjustments available for 480i output to rival the flexibility of the Extron VSC machines?

Could a future model include direct passthrough for analog input to the analog output? (No ADC and DAC sampling.) That would be convenient, but I think it might not be possible.

I would like to have a downscaler that can sit directly before a 15kHz CRT in the video chain. Corio2 analog units passthrough the signal directly when they are powered off. I don't have to use a splitter or a matrix switch at all. I don't have to plug a Corio2 into it's own input on a CRT, either. If I want downscaling, I turn it on. If I want to passthrough the analog signal, I turn it off. It's a pity the C2 has lag, no frame lock, and the interlaced output isn't good. It's so easy to use after it's configured.

It would be nice to have a single downscaling machine with digital and analog input, frame lock, low latency, analog ouput, robust signal compatibility, and complete support for both progressive and interlaced 15kHz output (that matches the features of existing solutions).

Of course, that isn't necessarily the mission statement for the OSSC Pro, but those features would make it the ultimate video game downscaler--and render absolutely every other option obsolete.
We apologise for the inconvenience
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Re: OSSC Pro

Post by Gunstar »

orange808 wrote: Sun Feb 02, 2025 7:32 pm flicker filter adjustments available for 480i output
Wanting/Waiting for this also.
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marqs
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Re: OSSC Pro

Post by marqs »

orange808 wrote: Sun Feb 02, 2025 7:32 pm Is there a planned unit with the analog option preinstalled inside a custom case or a case option for the analog board?
There is a model for extra AV out case you can 3D print or buy pre-made.
orange808 wrote: Sun Feb 02, 2025 7:32 pm Latency improvements will be welcome. Besides the analog extension case, that's the other reason I haven't purchased a machine yet.
Latency in (A-)LM mode is already as low as it gets. For scaler mode latency improvents you still need to wait longer.

It's not possible to directly pass thru analog in the current design, and output flicker filter is low on the priorities list.
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Re: OSSC Pro

Post by Zacabeb »

marqs wrote: Thu Feb 06, 2025 10:48 pm It's not possible to directly pass thru analog in the current design, and output flicker filter is low on the priorities list.
I feel that in order for a flicker filter to be useful when downscaling, the scaling itself would first need to be expanded to have more taps improving quality, effectively separating up- and downscaling filters to maintain MISTer compatibility. Then I imagine a flicker filter could be convolved with the scaling filter. Quite a lot of work.
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GK6475
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Re: OSSC Pro

Post by GK6475 »

So, what changes/additions could be expected in the next firmware update? Is an inverse telecine deinterlacing method in the works (for 30fps 480i content)? Maybe also a 2560x1920 line multiplier resolution for 480i/p? Also, I've noticed that the Freesync notification doesn't seem to be working with my LG CX anymore (I do have adaptive sync enabled on all inputs on the TV itself), did the last firmware update change something to cause this?
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Re: OSSC Pro

Post by marqs »

GK6475 wrote: Tue Feb 11, 2025 3:12 am So, what changes/additions could be expected in the next firmware update? Is an inverse telecine deinterlacing method in the works (for 30fps 480i content)? Maybe also a 2560x1920 line multiplier resolution for 480i/p? Also, I've noticed that the Freesync notification doesn't seem to be working with my LG CX anymore (I do have adaptive sync enabled on all inputs on the TV itself), did the last firmware update change something to cause this?
The next firmware will include the following:

* 1920x1440@60 input support for both analog and digital sources [Done]
* 1152x864_75 sampling preset added [Done]
* 2048x1536 and 2560x1920 (PR2x) output presets added [Done]
* LG VRR compatibility fixed [Done]
* Workaround for Mister SNES core jitter added [Done]
* Scaler framelocking consistency improved [Done]
* Support for RF (legacy AV expansion) [Under finalization]

I did a quick trial with 2:2 and 3:2 cadence detection and while it didn't seem to incur latency penalty when no cadence was detected, the additional FPGA resources required were higher than I hoped. At this point it's thus hard to justify adding it into base firmware, but I've been also doing some preparation work for multi-fw support (the internal flash could store 3-4 images).
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GK6475
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Re: OSSC Pro

Post by GK6475 »

marqs wrote: Tue Feb 11, 2025 11:53 pm
GK6475 wrote: Tue Feb 11, 2025 3:12 am So, what changes/additions could be expected in the next firmware update? Is an inverse telecine deinterlacing method in the works (for 30fps 480i content)? Maybe also a 2560x1920 line multiplier resolution for 480i/p? Also, I've noticed that the Freesync notification doesn't seem to be working with my LG CX anymore (I do have adaptive sync enabled on all inputs on the TV itself), did the last firmware update change something to cause this?
The next firmware will include the following:

* 1920x1440@60 input support for both analog and digital sources [Done]
* 1152x864_75 sampling preset added [Done]
* 2048x1536 and 2560x1920 (PR2x) output presets added [Done]
* LG VRR compatibility fixed [Done]
* Workaround for Mister SNES core jitter added [Done]
* Scaler framelocking consistency improved [Done]
* Support for RF (legacy AV expansion) [Under finalization]

I did a quick trial with 2:2 and 3:2 cadence detection and while it didn't seem to incur latency penalty when no cadence was detected, the additional FPGA resources required were higher than I hoped. At this point it's thus hard to justify adding it into base firmware, but I've been also doing some preparation work for multi-fw support (the internal flash could store 3-4 images).
Awesome to hear about RF support being finalized, and multi-fw would be great for those of us that want those niche features.
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Re: OSSC Pro

Post by traka-ar »

marqs Can a power off option be added please
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Re: OSSC Pro

Post by marqs »

traka-ar wrote: Thu Feb 13, 2025 8:22 pm marqs Can a power off option be added please
You mean like an option in the menu, in addition to having means of turning if off via remote or holding the front button?
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Re: OSSC Pro

Post by traka-ar »

marqs wrote: Fri Feb 14, 2025 8:52 am
traka-ar wrote: Thu Feb 13, 2025 8:22 pm marqs Can a power off option be added please
You mean like an option in the menu, in addition to having means of turning if off via remote or holding the front button?
Can it fully shutdown, no red light? Any is fine. I know it can go into standby but not fully off or maybe I missed the option
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Re: OSSC Pro

Post by Zacabeb »

traka-ar wrote: Fri Feb 14, 2025 7:23 pm Can it fully shutdown, no red light? Any is fine. I know it can go into standby but not fully off or maybe I missed the option
I think the best that could be done would be to add an option for the red LED to be turned off when the unit is in standby. Part of the FPGA is active in standby to keep watch for remote commands and handle the buttons on the unit itself, so the OSSC Pro can not have a hard shutdown option built-in unless a physical power switch is added.
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Re: OSSC Pro

Post by spmbx »

This is a pretty universal solution
Image
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Re: OSSC Pro

Post by Zacabeb »

Maybe the LED PWM duty cycle could be reduced further to allow dimming them very low?
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Kretinou
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Re: OSSC Pro

Post by Kretinou »

Hello. I just ordered an ossc pro. Concerning the memory card, do you have a recommendation on the capacity and possibly the brand to buy ? Thanks :D
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Re: OSSC Pro

Post by ryu »

Kretinou wrote: Mon Feb 17, 2025 9:13 am Hello. I just ordered an ossc pro. Concerning the memory card, do you have a recommendation on the capacity and possibly the brand to buy ? Thanks :D
Considering that small cards of 2 and 3 GB seem to be out of production I would assume that any card should be fine (but don't take my word on it, haven't been able to test it myself yet). I never had a problem with San Disk cards in general.

Is there a way to get a full picture from fake 16:9 sources like the Wii (without relying on the monitor to zoom in)? When I run Wii games and set the output aspect ratio to 16:9 the picture stretches all the way horizontally with huge black bars on top and bottom and I couldn't find a way to mitigate that behavior.
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Re: OSSC Pro

Post by Unseen »

ryu wrote: Tue Feb 18, 2025 6:49 amIs there a way to get a full picture from fake 16:9 sources like the Wii (without relying on the monitor to zoom in)? When I run Wii games and set the output aspect ratio to 16:9 the picture stretches all the way horizontally with huge black bars on top and bottom and I couldn't find a way to mitigate that behavior.
Did you tell your Wii that you have a 16:9 TV?
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Re: OSSC Pro

Post by ryu »

Unseen wrote: Tue Feb 18, 2025 8:41 am
ryu wrote: Tue Feb 18, 2025 6:49 amIs there a way to get a full picture from fake 16:9 sources like the Wii (without relying on the monitor to zoom in)? When I run Wii games and set the output aspect ratio to 16:9 the picture stretches all the way horizontally with huge black bars on top and bottom and I couldn't find a way to mitigate that behavior.
Did you tell your Wii that you have a 16:9 TV?
Oh I'm dumb. Yeah that might be it. The one game I tested for widescreen I may not have applied 16:9 mode for :? Thanks

Everytime the OSSC Pro switches input modes my display soft reboots because it detects a change in input (or a short loss of input). This is really bad for games that switch between 240p and 480i during gameplay (Silent Hill) because each transition causes about 3-5 seconds of black screen. Is there anything I can do to prevent the scaler from breaking or switching the output signal?
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