OSSC Pro

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marqs
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Re: OSSC Pro

Post by marqs »

FRL is quite new feature in HDMI (v2.1) and not supported by the selected v1.4 transmitter chip (SiI1136). Big companies nowadays implement HDMI functionality integrated straight into ASIC / FPGA, I'm not even aware of any publicly available dedicated HDMI 2.0 transmitter chips.
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Josh128
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Re: OSSC Pro

Post by Josh128 »

Bahn Yuki wrote:
incrediblehark wrote:After testing out my retrotink 5x pro for a couple of months, I have gone back to my original OSSC with my HDCRT. For the most part the 5x works very well, but still has sync issues with the Neo Geo AES and it doesn't play well with the RGC Dreamcast scart cable with 480p/480i switch, which works flawlessly with the OSSC. I haven't completely given up on the 5x yet, hoping that future firmware updates will fix these issues. Basically what I'm saying is I'm back on board with the OSSC and hoping to get the Pro when it is released soon, especially if it retains the original's compatibility.
Which hd crt do you have?

Sent from my SM-G991U using Tapatalk
He was using a KV-40XBR800 as we discussed in the 240 to 540p for SONY Trinitron KV-32HS510 HDCRT Dump Find thread, but iirc his set displayed 540p as 1080i and I think it did not have the 0 lag HDPT circuitry.
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VEGETA
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Re: OSSC Pro

Post by VEGETA »

marqs wrote:FRL is quite new feature in HDMI (v2.1) and not supported by the selected v1.4 transmitter chip (SiI1136). Big companies nowadays implement HDMI functionality integrated straight into ASIC / FPGA, I'm not even aware of any publicly available dedicated HDMI 2.0 transmitter chips.
you can check this: https://www.ite.com.tw/en/product/view?mid=155

and the rest of the ICs there.
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marqs
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Re: OSSC Pro

Post by marqs »

VEGETA wrote:
marqs wrote:FRL is quite new feature in HDMI (v2.1) and not supported by the selected v1.4 transmitter chip (SiI1136). Big companies nowadays implement HDMI functionality integrated straight into ASIC / FPGA, I'm not even aware of any publicly available dedicated HDMI 2.0 transmitter chips.
you can check this: https://www.ite.com.tw/en/product/view?mid=155

and the rest of the ICs there.
IT6615 looks interesting, but its "4k60" seems to be limited to YCbCr 4:2:0 unless listed 6Gbps is for single TMDS channel (i.e. 18Gbps total). I'm also not sure if it could be considered publicly available, at least no datasheet is given.
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VEGETA
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Re: OSSC Pro

Post by VEGETA »

marqs wrote:
VEGETA wrote:
marqs wrote:FRL is quite new feature in HDMI (v2.1) and not supported by the selected v1.4 transmitter chip (SiI1136). Big companies nowadays implement HDMI functionality integrated straight into ASIC / FPGA, I'm not even aware of any publicly available dedicated HDMI 2.0 transmitter chips.
you can check this: https://www.ite.com.tw/en/product/view?mid=155

and the rest of the ICs there.
IT6615 looks interesting, but its "4k60" seems to be limited to YCbCr 4:2:0 unless listed 6Gbps is for single TMDS channel (i.e. 18Gbps total). I'm also not sure if it could be considered publicly available, at least no datasheet is given.
I have got details for a similar one which uses a different input digital video, but this one should be identical. it supports up to 8bpp 4k60 8-bit RGB signal. if you go 10 bit then it will be internally converted to either 420 ypbpr or 8-bit rgb. since you are using 8-bit rgb then no problem at all. their chips has hdcp and non-hdcp versions.

all you need is to sign an NDA to get everything.
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Re: OSSC Pro

Post by Unseen »

VEGETA wrote:all you need is to sign an NDA to get everything.
I suspect that NDA would conflict with the OS part of the OSSC.
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VEGETA
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Re: OSSC Pro

Post by VEGETA »

Unseen wrote:
VEGETA wrote:all you need is to sign an NDA to get everything.
I suspect that NDA would conflict with the OS part of the OSSC.
well, if he doesn't distribute datasheets and support material then it doesn't collide with open source.

if he made his own code (which he does), then it is not a violation. he can put the schematics online + code and no one will ever need to know what is inside the datasheets or app notes anyway.
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marqs
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Re: OSSC Pro

Post by marqs »

VEGETA wrote:
Unseen wrote:
VEGETA wrote:all you need is to sign an NDA to get everything.
I suspect that NDA would conflict with the OS part of the OSSC.
well, if he doesn't distribute datasheets and support material then it doesn't collide with open source.

if he made his own code (which he does), then it is not a violation. he can put the schematics online + code and no one will ever need to know what is inside the datasheets or app notes anyway.
It goes into the grey area as NDA limits the amount of information you are able to disclose (possibly in form of headers, code and documentation/comments too). Not worth taking the risk of getting sued - in projects like this you'd have to use whatever information is available online and reverse engineer the rest.
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VEGETA
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Re: OSSC Pro

Post by VEGETA »

but didn't you use Intel scaler IP while being an "IP" which is not free? how is that possible to fit in this project?

do you know any open source fpga project code for simple video scaler application as an example? or is all of it commercial IPs?

I do understand your choice and since you don't need 4k60 then your ICs and the one from analog devices are enough.
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marqs
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Re: OSSC Pro

Post by marqs »

VEGETA wrote:but didn't you use Intel scaler IP while being an "IP" which is not free? how is that possible to fit in this project?
It's not about being free or not. Purchasing Intel video IP license does not give you any extra information (such as source code) nor it requires signing a NDA. Effectively it just enables to use the IP (already included with the tools) without restrictions and grants access to support forum. In practice most FPGA projects end up using some non-open vendor IP (e.g. PLL, memory controllers), only some Lattice FPGAs can be developed fully without vendor tools/IP and that's mostly thanks to reverse engineering.
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marqs
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Re: OSSC Pro

Post by marqs »

Some good news, some bad news.

Good news is that we have got everything ready for production, case design being the last item (pictures below) that got finalized early December. Prototype runs with final/near-final PCB have been made with two different manufacturers during 2021, and we've got a handful of boards that could be shared with people willing to help developing the firmware further.

Image


The bad news is that component shortage forces us postpone launch until the situation takes a step towards normal. Things have got progressively worse lately and there are a bunch of key parts that now cost anything between 3-30x of their normal price on spot market, making it infeasible to kick off a large production run. I've recently spent quite a bit of time with the manufacturer trying to find these parts at more reasonable prices to cover at least a limited run, but without much luck. Focus is now switched on to manufacturing DExx-vd_isl boards (not as badly affected by shortages) which can act as more afforable yet limited substitute until times get better.
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Re: OSSC Pro

Post by Dochartaigh »

marqs wrote:Some good news, some bad news.

Good news is that we have got everything ready for production, case design being the last item (pictures below) that got finalized early December. Prototype runs with final/near-final PCB have been made with two different manufacturers during 2021, and we've got a handful of boards that could be shared with people willing to help developing the firmware further.
Picture link isn't displaying for me, here it is linked to Imgur:

And Marqs, I'm SO HAPPY you got (nearly) all the ports off the back (like every mass produced, industrial designed, electronics device in the past ~80 years has had, rightfully so!!!).

Couple quick questions: can you bypass the SCART port on the side and simply use a VGA (or SCART to VGA adapter, or VGA to BNC adapter cable) and run everything (RGBS, RGsB, RGBHV, Component, --maybe even Composite and S-Video like Extron/TVOne/Crestron/Kramer/etc do through their DB15 ports as well) through the DB15/VGA port on the back? That would be ideal and keep the look of this beautiful device with ALL the cables running off the back aesthetically.

The LPF is available on the DB15, right? I thought this was updated on a later OSSC firmware, but I know at first the DB15 port lacked the Low Pass Filter the SCART port had, and that LPF is a must for these older consoles IMO.

The SCART port (IF people use it of course), points out the rear of the device, correct? Not like other a certain other scaler which for some reason made it point forward (a common complaint... so much so people have built converters to switch it back to the 'proper' direction, i.e. out the rear).

The OSSC Pro is supposed to do things like downscale, too, correct? That's one of the things I'm most excited about, making this an all-in-one scaling device (both UP and DOWNscaling). I assume the downscaling would be for CRT use mostly (downscaling to 240p for SD/Standard Definition CRT's, + perhaps scaling to 540p so HDCRT's can be nearly lagless). Where is the (2nd?) analog port for output of the scaled image though? I see Component, DB15, and SCART - I assume those are for inputs as those are common console connection types and many people would be using all 3x of those at once, but how would one hook up to it for analog output of the downscaled image?
Last edited by Dochartaigh on Thu Jan 13, 2022 9:38 pm, edited 1 time in total.
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Re: OSSC Pro

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Re: OSSC Pro

Post by bobrocks95 »

Dochartaigh wrote:The LPF is available on the DB15, right? I thought this was updated on a later OSSC firmware, but I know at first the DB15 port lacked the Low Pass Filter the SCART port had, and that LPF is a must for these older consoles IMO.
It was never added to the original, it was something along the lines of the chip the port ran through didn't support it or it had a bug disabling it. Regardless I believe marqs said before that wouldn't be a problem on the Pro. I would be curious what variety of input signals it accepts though, I'd hope at least RGBHV and RGBS.
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Re: OSSC Pro

Post by Dochartaigh »

bobrocks95 wrote:It was never added to the original, it was something along the lines of the chip the port ran through didn't support it or it had a bug disabling it. Regardless I believe marqs said before that wouldn't be a problem on the Pro. I would be curious what variety of input signals it accepts though, I'd hope at least RGBHV and RGBS.
I'm hoping the DB15 port will have pro features like my other 'pro' video devices have. Industry standard/large companies like Extron, Kramer, Crestron, TVOne (on select units of each capable of using these types) can take a HUGE assortment of inputs over a DB15 cable (commonly using the standard DB15 to 5x BNC cable or adapter dongle).

On certain units, switchers, converters, transcoders, up/down scalers I can input everything from Composite to S-Video, to RGBS, RGsB, Component, and RGBHV over the same DB15 input. AND they have the same exact pin-out between all these companies (i.e. my 'industry standard' statement above). (Sidenote: please don't do like Analog did on their NES console and use the PC format for CV/YC... those cables are NOT industry standard pinouts).

I think the original OSSC does similar over DB15 for higher-end signals (quoting their wiki) "RGBHV, RGBS, RGsB and YPbPr format", so adding in some lower signal types (which correct me if I'm wrong but I think the OSSC Pro can take too, perhaps at a later date with a firmware update I think they said) should be a piece of cake and give an all-in-one connection type. A super flexible connection type like this would make setup a breeze for peoples larger setups (using switchers) since you would need ONE SINGLE OUTPUT CABLE, instead of running separate cables for composite, s-video, RGBS, component, VGA/RGBHV, etc. (which would be crazy to have to run all those multiple cables when they could be run over a single DB15 cable).
mikechi2
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Re: OSSC Pro

Post by mikechi2 »

marqs wrote:Some good news, some bad news.

Good news is that we have got everything ready for production, case design being the last item (pictures below) that got finalized early December. Prototype runs with final/near-final PCB have been made with two different manufacturers during 2021, and we've got a handful of boards that could be shared with people willing to help developing the firmware further.

Image


The bad news is that component shortage forces us postpone launch until the situation takes a step towards normal. Things have got progressively worse lately and there are a bunch of key parts that now cost anything between 3-30x of their normal price on spot market, making it infeasible to kick off a large production run. I've recently spent quite a bit of time with the manufacturer trying to find these parts at more reasonable prices to cover at least a limited run, but without much luck. Focus is now switched on to manufacturing DExx-vd_isl boards (not as badly affected by shortages) which can act as more afforable yet limited substitute until times get better.
Congratulations Marqs on busting this out basically singlehanded. Looks awesome. Just a (stupid) question. Is there a chance that the Cyclone V IO can one day be coaxed to output some form of 4K using an HDMI TX core inside the FPGA itself?
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marqs
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Re: OSSC Pro

Post by marqs »

Dochartaigh wrote:Couple quick questions: can you bypass the SCART port on the side and simply use a VGA (or SCART to VGA adapter, or VGA to BNC adapter cable) and run everything (RGBS, RGsB, RGBHV, Component, --maybe even Composite and S-Video like Extron/TVOne/Crestron/Kramer/etc do through their DB15 ports as well) through the DB15/VGA port on the back? That would be ideal and keep the look of this beautiful device with ALL the cables running off the back aesthetically.
Both SCART and DB-15 connectors support RGB/component signals with HV, SoG and composite (both TTL and 75ohm terminated) sync. A few normally unused pins of both connectors are utilized for "extra" sync inputs (i.e. HV for SCART and 75ohm c-sync for DB-15) so everything can work with passthru adapters.
Dochartaigh wrote:The LPF is available on the DB15, right? I thought this was updated on a later OSSC firmware, but I know at first the DB15 port lacked the Low Pass Filter the SCART port had, and that LPF is a must for these older consoles IMO.
All video inputs are hooked directly to video ADC which supports fine-grained LPF.
Dochartaigh wrote:The SCART port (IF people use it of course), points out the rear of the device, correct? Not like other a certain other scaler which for some reason made it point forward (a common complaint... so much so people have built converters to switch it back to the 'proper' direction, i.e. out the rear).
Yes, the cable goes towards rear of the device.
Dochartaigh wrote:The OSSC Pro is supposed to do things like downscale, too, correct? That's one of the things I'm most excited about, making this an all-in-one scaling device (both UP and DOWNscaling). I assume the downscaling would be for CRT use mostly (downscaling to 240p for SD/Standard Definition CRT's, + perhaps scaling to 540p so HDCRT's can be nearly lagless). Where is the (2nd?) analog port for output of the scaled image though? I see Component, DB15, and SCART - I assume those are for inputs as those are common console connection types and many people would be using all 3x of those at once, but how would one hook up to it for analog output of the downscaled image?
For analogue output you'd need an expansion card like one shown on page 55 or HDMI->VGA adapter.
mikechi2 wrote:Congratulations Marqs on busting this out basically singlehanded. Looks awesome. Just a (stupid) question. Is there a chance that the Cyclone V IO can one day be coaxed to output some form of 4K using an HDMI TX core inside the FPGA itself?
Thanks. I have had some help during the way but overall the task has perhaps been a bit too ambitious for a free-time project. 4K HDMI TX would need Cyclone V chip with transceivers (preferably 6Gbps), but Cyclone 10GX or Arria 10 would probably suit better overall for such feature. That said, even the current solution could support 4K output at 30Hz but obviously that'd be quite useless with games.
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Re: OSSC Pro

Post by PearlJammzz »

I assume that development is still ongoing with the OSSC Pro, correct? It isn't that the project is dead per say, just that hardware availability has postponed the hardware release. With that said, I suppose a silver lining is that when we can get our hands on the OSSC Pro the device should be more feature rich than we would otherwise have at launch?

Can't wait for this hardware shortage to be over so we can all get a chance to play with a new OSSC! Thanks again for all your hard work Marqs and everyone else involved with the project.
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Re: OSSC Pro

Post by NormalFish »

Yeah, curious to hear if this might move forward your own implementation of motion adaptive deinterlacing, Marqs. Realize it's a stressful time and you've already cranked out a lot so don't want to put additional pressure on you, but that would be neat.

**Or rather, not move forward, but will mean you might be done or close to done with it prior to launch.
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lamp
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Re: OSSC Pro

Post by lamp »

Just started following the development of the OSSC Pro and it is looking great so far!
marqs wrote: I have had some help during the way but overall the task has perhaps been a bit too ambitious for a free-time project.
Is there any way for the community to help contribute and give back in a meaningful way? I'm a software engineer (but I do have some System Verilog experience) and while I'm not sure if I would be able to dedicate a significant portion of time, I'm sure others (and myself) would be willing to pitch in and contribute whenever we did have free time. I know there are the Github repositories but just looking at those it is not clear what work is still outstanding and how to start contributing. (Please let me know if there is in fact a resource that keeps track of this as I am not fully up to date on where things are being tracked)

Keep up the great work and let me know if there's anyway to help out!
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marqs
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Re: OSSC Pro

Post by marqs »

lamp wrote:
marqs wrote: I have had some help during the way but overall the task has perhaps been a bit too ambitious for a free-time project.
Is there any way for the community to help contribute and give back in a meaningful way? I'm a software engineer (but I do have some System Verilog experience) and while I'm not sure if I would be able to dedicate a significant portion of time, I'm sure others (and myself) would be willing to pitch in and contribute whenever we did have free time. I know there are the Github repositories but just looking at those it is not clear what work is still outstanding and how to start contributing. (Please let me know if there is in fact a resource that keeps track of this as I am not fully up to date on where things are being tracked)
There are many things to be done both among core functionality and specific features/expansions. The latter category is something that could suit best for guys looking to contribute every now and then at their own pace. What the contributions could be comes down to each one's own interests, but I listed a few example items below which would be cool to have someone working on:

1. CVBS/S-video support. Ideally by decoding ADCed signal on FPGA, but an expansion card with ADV7280 or similar is a possibility too.
2. USB UVC Bridge expansion for capture/streaming purposes.
3. Porting & testing some emulator cores on the board.
4. Audio interface conversions between SPDIF and I2S.

Obviously the limited amount of boards and documentation available is making things difficult right now, but anyone interested can PM me. We're also planning to increase our presence on Discord as it's popular among many devs.
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Re: OSSC Pro

Post by Hao »

Any updates for those still frothing at the mouth for this?
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marqs
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Re: OSSC Pro

Post by marqs »

Hao wrote:Any updates for those still frothing at the mouth for this?
The shortages still continue so currently there's no definite date which could be given. Most likely we're able to make some DExx-vd_isl boards first, perhaps even by summer, since they have fewer hard-to-get parts.
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Re: OSSC Pro

Post by kitty666cats »

bobrocks95 wrote:
Dochartaigh wrote:The LPF is available on the DB15, right? I thought this was updated on a later OSSC firmware, but I know at first the DB15 port lacked the Low Pass Filter the SCART port had, and that LPF is a must for these older consoles IMO.
It was never added to the original, it was something along the lines of the chip the port ran through didn't support it or it had a bug disabling it. Regardless I believe marqs said before that wouldn't be a problem on the Pro. I would be curious what variety of input signals it accepts though, I'd hope at least RGBHV and RGBS.
You can send RGB into the component input and HV into the VGA to accomplish that, just need two spare VGA to BNC cables and some RCA adapters
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marqs
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Re: OSSC Pro

Post by marqs »

marqs wrote:
Hao wrote:Any updates for those still frothing at the mouth for this?
The shortages still continue so currently there's no definite date which could be given. Most likely we're able to make some DExx-vd_isl boards first, perhaps even by summer, since they have fewer hard-to-get parts.
While the market situation for components hasn't really improved, we've managed to secure enough parts for some DExx-vd_isl boards and its pilot batch should be available in 1-2 months. It may not exactly be the complete product most people here are waiting for, but under the circumstances it's the best we can offer. Discord channels under Classic Gaming have been also added for anyone interested in discussion on these HW or development for them.
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orange808
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Re: OSSC Pro

Post by orange808 »

Does MiSTer's new VRR experiment mean the OSSC Pro hardware could also output VRR?
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marqs
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Re: OSSC Pro

Post by marqs »

orange808 wrote:Does MiSTer's new VRR experiment mean the OSSC Pro hardware could also output VRR?
I haven't looked into that experiment but I presume it's done by sending a signal with variable vblank duration to the HDMI transmitter and by customizing Infoframe. OSSC Pro uses similar yet more powerful HDMI transmitter chip so I see no reason why the same wouldn't work there.
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Re: OSSC Pro

Post by NewSchoolBoxer »

Can I ask about the "Reverse LPF" that OSSC and presumably OSSC Pro have in the software? No information online about it, other than it exists. I assume it makes the group delay more linear, which is a really good idea. Every analog filter induces non-linear group delay on frequencies near the cutoff, which is a form of distortion.
kitty666cats wrote:
bobrocks95 wrote:
Dochartaigh wrote:The LPF is available on the DB15, right? I thought this was updated on a later OSSC firmware, but I know at first the DB15 port lacked the Low Pass Filter the SCART port had, and that LPF is a must for these older consoles IMO.
It was never added to the original, it was something along the lines of the chip the port ran through didn't support it or it had a bug disabling it. Regardless I believe marqs said before that wouldn't be a problem on the Pro. I would be curious what variety of input signals it accepts though, I'd hope at least RGBHV and RGBS.
You can send RGB into the component input and HV into the VGA to accomplish that, just need two spare VGA to BNC cables and some RCA adapters
Sending RGB into component and HV into VGA is genius. Looking at PDF of OSSC schematic, optional LPF is provided by the THS7353. Has a built-in 2:1 mux that SCART and component inputs are tied to. Could have muxed VGA with one of those externally or added a chip just for VGA. Either option is kind of awkward. Glad the Pro has optional LPF on every input.
kitty666cats wrote: Getting an OSSC Pro just for downscaling would be overkill and silly... read this:

https://medium.com/rgb-inside/gbs-8200- ... 5d3b6907be

Or watch this:

https://www.youtube.com/watch?v=mcqskbCWPCs



~~~~~~~~~~~~~~~

https://www.tindie.com/products/chipnet ... converter/

^ one of our very own members sells these, if you're not into soldering and stuff
Impressive as that encyclopedic article is, I'm amused someone who can acquire a PVM-14L5 and BVM-20F1U (and C2G 6x2 Component Matrix) can't pay someone else to switch R26 from 150 to 110 ohms before taking pictures when they're aware of the fix. Could put a resistor close to ideal 412.5 ohms in parallel with the 150 instead.
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Re: OSSC Pro

Post by XtraSmiley »

Hey @marqs, any update on the software side to do the rotation feature?
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marqs
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Re: OSSC Pro

Post by marqs »

NewSchoolBoxer wrote:Can I ask about the "Reverse LPF" that OSSC and presumably OSSC Pro have in the software? No information online about it, other than it exists. I assume it makes the group delay more linear, which is a really good idea. Every analog filter induces non-linear group delay on frequencies near the cutoff, which is a form of distortion.
You can think it as removing a portion of the difference between current and previous pixel from currently processed pixel to eliminate some unintended bleeding from the video signal.
XtraSmiley wrote:Hey @marqs, any update on the software side to do the rotation feature?
Design of custom framebuffer IP to enable rotation, screenshots and lower latency in scaler mode is one on the next things on todo. I should be able to start working on it after summer.
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