Koryuu (Composite & S-Video to YPbPr Transcoder) Coming 2020

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SamIAm
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Re: Koryuu (Composite & S-Video to YPbPr Transcoder) Coming

Post by SamIAm »

fernan1234 wrote:Thanks.

I have exactly one machine that I'd be interested to pair with something like this, a PC-FX, which only does S-video at best. I hook it up directly to a BVM with Y/C input and it looks very nice, but of course less sharp and a colors bit duller than RGB would. If a converter like this adequately separates the color signals for the monitor, I'd imagine the result would be an improvement over direct S-video.
Ah. I have a PC-FX myself.

The loss in sharpness and the dullness of the colors you see is the result of the S-Video encoding itself. You'll never get that quality back no matter what is decoding the signals back to RGB.

The Y/C processing inside your BVM is almost certainly more sophisticated and produces a better picture than what's inside the YR-421. It really wouldn't be useful for you. I would never use mine on a monitor that had built-in S-Video support. I only got it because I have three really good Ikegami HTM monitors that have nothing other than RGB/YPbPr inputs on them.
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Lawfer
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Re: Koryuu (Composite & S-Video to YPbPr Transcoder) Coming

Post by Lawfer »

SamIAm wrote:Ah. I have a PC-FX myself.

The loss in sharpness and the dullness of the colors you see is the result of the S-Video encoding itself. You'll never get that quality back no matter what is decoding the signals back to RGB.

The Y/C processing inside your BVM is almost certainly more sophisticated and produces a better picture than what's inside the YR-421. It really wouldn't be useful for you. I would never use mine on a monitor that had built-in S-Video support. I only got it because I have three really good Ikegami HTM monitors that have nothing other than RGB/YPbPr inputs on them.
Just curious, are you the guy working on Princess Crown?
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Re: Koryuu (Composite & S-Video to YPbPr Transcoder) Coming

Post by SamIAm »

Lawfer wrote:Just curious, are you the guy working on Princess Crown?
Aye.
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Lawfer
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Re: Koryuu (Composite & S-Video to YPbPr Transcoder) Coming

Post by Lawfer »

SamIAm wrote:
Lawfer wrote:Just curious, are you the guy working on Princess Crown?
Aye.
I see, been waiting for it, good job and good luck.
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Re: Koryuu (Composite & S-Video to YPbPr Transcoder) Coming

Post by SamIAm »

Thanks! Hope you like it when it's done. :D
fernan1234
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Re: Koryuu (Composite & S-Video to YPbPr Transcoder) Coming

Post by fernan1234 »

SamIAm wrote:
Ah. I have a PC-FX myself.

The loss in sharpness and the dullness of the colors you see is the result of the S-Video encoding itself. You'll never get that quality back no matter what is decoding the signals back to RGB.

The Y/C processing inside your BVM is almost certainly more sophisticated and produces a better picture than what's inside the YR-421. It really wouldn't be useful for you. I would never use mine on a monitor that had built-in S-Video support. I only got it because I have three really good Ikegami HTM monitors that have nothing other than RGB/YPbPr inputs on them.
I see. I was having some unreasonable hope that the Sony wizards figured out a way to reconstruct, or most likely make a guess of, some of the degradation caused by the S-video encoding.

BTW, on PC-FX I'm currently playing Megami Paradise/Tengoku II. What a unique game! Never seen such a gameplay system anywhere else. It's overall the kind of distinct gameplay that the PC-FX seemed to target (demanding a lot of player interaction and patience, combining multiple game genres, with time tracking and day/season cycles, etc.), like Blue Breaker. It's sad that the PC-FX failed as badly as it did and that in the West it's mostly known as an adult adventure game system. Anyway, in case you haven't, I really recommend checking that game out.

BTW2, thanks for your work in translating Princess Crown, it's a very pretty game and it's nice that it'll reach more players with a translation.
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maxtherabbit
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Re: Koryuu (Composite & S-Video to YPbPr Transcoder) Coming

Post by maxtherabbit »

orange808 wrote: We should avoid using composite whenever possible
I feel the same way about Y/C lol

they are both substandard as hell compared to YPbPr/RGB
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orange808
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Re: Koryuu (Composite & S-Video to YPbPr Transcoder) Coming

Post by orange808 »

maxtherabbit wrote:
orange808 wrote: We should avoid using composite whenever possible
I feel the same way about Y/C lol

they are both substandard as hell compared to YPbPr/RGB
Of course.

But, svideo has a huge advantage over composite. It can be processed and upscaled to a sharp digital display without the aid of a comb filter.

And, *truly* good comb filters are very rare. Truly good ones that handle 240p properly and don't add some lag probably don't exist.
We apologise for the inconvenience
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Lawfer
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Re: Koryuu (Composite & S-Video to YPbPr Transcoder) Coming

Post by Lawfer »

maxtherabbit wrote:
orange808 wrote: We should avoid using composite whenever possible
I feel the same way about Y/C lol

they are both substandard as hell compared to YPbPr/RGB
That goes without saying, but in some cases it's unavoidable, for example try to get RGB or YPbPr from an FM Towns Marty, the best you can get will be S-Video.

SamIAm wrote:I only got it because I have three really good Ikegami HTM monitors that have nothing other than RGB/YPbPr inputs on them.
Same issue here, there ain't even any optional add-on card module to add S-Video either.
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kitty666cats
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Re: Koryuu (Composite & S-Video to YPbPr Transcoder) Coming

Post by kitty666cats »

SamIAm wrote:Thanks! Hope you like it when it's done. :D
2019 and 2020 are great years for the Saturn, gawdayum. Grandia, Sakura Wars, Lunar, Princess Crown, wireless controllers... whew!
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Re: Koryuu (Composite & S-Video to YPbPr Transcoder) Coming

Post by SamIAm »

Lawfer wrote:That goes without saying, but in some cases it's unavoidable, for example try to get RGB or YPbPr from an FM Towns Marty, the best you can get will be S-Video.
The PC-FX is similar. It's got four separate chips doing various kinds of video processing, and IIRC two of them work in RGB while two are in YUV. It would be enormously complicated to create some kind of bus-sniffing digital processor like what's available for the NES, and since the potential audience is vanishingly small, it'll mostly likely never happen.
Same issue here, there ain't even any optional add-on card module to add S-Video either.
I seem to remember you having a 1990R?

It's a shame, there is a table in some Ikegami literature out there that says S-Video would be available as an "option", but the list of actual expansion boards that I've found doesn't have anything like that. Just a regular old NTSC/PAL board.

(I actually have an NTSC board, but it's broken.)
fernan1234 wrote:BTW, on PC-FX I'm currently playing Megami Paradise/Tengoku II. What a unique game! Never seen such a gameplay system anywhere else. It's overall the kind of distinct gameplay that the PC-FX seemed to target (demanding a lot of player interaction and patience, combining multiple game genres, with time tracking and day/season cycles, etc.), like Blue Breaker. It's sad that the PC-FX failed as badly as it did and that in the West it's mostly known as an adult adventure game system. Anyway, in case you haven't, I really recommend checking that game out.
That is the game that I would say is the most PC-FX PC-FX game, if that makes any sense (not a typo). It's also interesting in that unlike Blue Breaker and Fire Woman Matoigumi, it was never ported to another console.
Dochartaigh
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Re: Koryuu (Composite & S-Video to YPbPr Transcoder) Coming

Post by Dochartaigh »

svensonson wrote:good news! I`ve been waiting for something similar for some time until I came across a corio2.

I used a Corio2 2205 to transcode composite and s-video into ypbpr and even rgbs. C64 and MSX never looked better on a CRT.
I don't think I've ever used CV or YC on my Corio2's. How do you get it to convert without scaling? (I'm assuming you still want to use it in SD since you mentioned a CRT).



SamIAm wrote:There is another Japan-only product that converts S-Video to RGB called the YR-421. It was actually made by Sony in the late 80s for certain models of their Profeel Pro monitors that didn't have S-Video inputs built in. You can only buy it via auction anymore, but if you're patient, it can be had for 1000-2000 yen, and listings appear surprisingly often.

https://page.auctions.yahoo.co.jp/jp/auction/w351139563

I have one of these and it's...OK. To be honest, when running a comparison on a pro monitor that has both S-Video and RGB inputs, the monitor's built-in S-Video inputs are obviously better, even after having recapped the YR-421. Nonetheless, if I were stuck with one monitor that didn't have S-Video inputs, I'd be very happy to have it.
SamIAm wrote:Sync output is still sync-on-luma, though. I had to mod in an LM1881 inside mine to make it work with my matrix switch.
I've owned two of these YR-412's, could never get them to work right (and it's been so long I honestly forget what was wrong with them). Did you just replace every cap on it? Think I still have one somewhere around here and have a desoldering gun too....

Will also have to double check that I wasn't looping it in/out of my Crosspoint either (pretty sure the first one I got was before I used my Crosspoint for testing everything like I do now), because that would make it not work if it doesn't output csync.




For other units which will do CV and/or YC to RGBS or YPbPr I really like the Kramer FC-4044. I've had three of them so far, and think my first unit needed the largest cap replaced? but then worked perfect. Next two after that (which I still have) were perfect. Can output RGBS or YPbPr as well (I probably used the YPbPr at some point but usually only do RGBS). There's been maybe 6ish on eBay in the last year or so, so not super easy to find but they come up from time to time at least.

Other Kramers can do this as well but all those have been jacked up for me in some way so I can only recommend the 4044.

Extron makes the Extron CD 400 as well, which is a pretty old unit, but the one I scored off eBay looks great. I just use the Kramer because that's rack mountable and the Extron isn't (has a plastic case for some reason). Multiple ones on eBay now, but find one who will accept a 'best offer' for a LOT less than those are up for now.
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Re: Koryuu (Composite & S-Video to YPbPr Transcoder) Coming

Post by SamIAm »

Dochartaigh wrote:I've owned two of these YR-412's, could never get them to work right (and it's been so long I honestly forget what was wrong with them). Did you just replace every cap on it? Think I still have one somewhere around here and have a desoldering gun too....

Will also have to double check that I wasn't looping it in/out of my Crosspoint either (pretty sure the first one I got was before I used my Crosspoint for testing everything like I do now), because that would make it not work if it doesn't output csync.
Yeah, I replaced every cap. I also checked the sync on an oscilloscope, and it was definitely sync-on-luma.

I didn't know about those Kramer units. I'd love to try one. The YR-421 definitely left room for improvement.
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Xyga
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Re: Koryuu (Composite & S-Video to YPbPr Transcoder) Coming

Post by Xyga »

kitty666cats wrote:
SamIAm wrote:Thanks! Hope you like it when it's done. :D
2019 and 2020 are great years for the Saturn, gawdayum. Grandia, Sakura Wars, Lunar, Princess Crown, wireless controllers... whew!
Princess Crown and Satiator at the very top of the most anticipated upcoming Saturn news, definitely.

(sorry more OT but I couldn't help)
Strikers1945guy wrote:"Do we....eat chicken balls?!"
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Lawfer
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Re: Koryuu (Composite & S-Video to YPbPr Transcoder) Coming

Post by Lawfer »

SamIAm wrote:The PC-FX is similar. It's got four separate chips doing various kinds of video processing, and IIRC two of them work in RGB while two are in YUV. It would be enormously complicated to create some kind of bus-sniffing digital processor like what's available for the NES, and since the potential audience is vanishingly small, it'll mostly likely never happen.
Yeah less popular and most obscure consoles such as the PC-FX and FM Towns Marty who never came outside of Japan and only have games in Japanese as a result (except for 1 or 2 PC-FX games who got a fan-translation) have no RGB modding solutions unlike the most popular ones (NES, N64 etc.)

SamIAm wrote:I seem to remember you having a 1990R?
Yep that's the one I got.

SamIAm wrote:It's a shame, there is a table in some Ikegami literature out there that says S-Video would be available as an "option", but the list of actual expansion boards that I've found doesn't have anything like that. Just a regular old NTSC/PAL board.
Interesting! I looked for something like that 2 years ago or so but found zero information on it, might you have the model number? Just curious, cause I thought that it didn't even exist, I think there is one for Composite but like I said for S-Video I found zero info on it so thought that it didn't exist.

Xyga wrote:
kitty666cats wrote:
SamIAm wrote:Thanks! Hope you like it when it's done. :D
2019 and 2020 are great years for the Saturn, gawdayum. Grandia, Sakura Wars, Lunar, Princess Crown, wireless controllers... whew!
Princess Crown and Satiator at the very top of the most anticipated upcoming Saturn news, definitely.

(sorry more OT but I couldn't help)
Lunar? Haven't heard of that, tried to google found zero info. I have both Lunar on PS1 (USA versions).
SamIAm
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Re: Koryuu (Composite & S-Video to YPbPr Transcoder) Coming

Post by SamIAm »

Lawfer wrote:Interesting! I looked for something like that 2 years ago or so but found zero information on it, might you have the model number? Just curious, cause I thought that it didn't even exist, I think there is one for Composite but like I said for S-Video I found zero info on it so thought that it didn't exist.
I can't find the the one that says S-Video would be available just now, but I'll keep looking.

http://www.broadcaststore.com/pdf/model ... 5_1505.pdf

This gives a nice list of boards that actually do exist.
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Re: Koryuu (Composite & S-Video to YPbPr Transcoder) Coming

Post by DirkSwizzler »

I see an "Input Change" button.

Please tell me that this device can remember the last input it was set to when powered off then back on. Or that the default can be set somehow. Or, if both of those are false, that the default is s-video.

I'm really hoping the Koryuu can simplify my automatic setup. For that to be true I need 2 things.
1. It cannot output any sync signal when there's no input sync.
*It made me really sad that the RetroTink X2 outputs a test pattern by default.
2. It has to either automatically detect which input is active and switch to it. Or, allow me to have 2 separate Koryuu's hooked up that are each poised to handle different inputs.

If #2 is a spectacular failure. I can at least set up a passive transcode from cvbs to s-video. But if that falls apart as well if the default input is cvbs.
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Re: Koryuu (Composite & S-Video to YPbPr Transcoder) Coming

Post by kitty666cats »

I wonder how this thing would look with my LaserDisc player, as LaserDiscs were natively recorded in composite. Curious!
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kitty666cats
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Re: Koryuu (Composite & S-Video to YPbPr Transcoder) Coming

Post by kitty666cats »

Lawfer wrote: Lunar? Haven't heard of that, tried to google found zero info. I have both Lunar on PS1 (USA versions).
MsTea is the person working on Lunar, some info on it on SegaXtreme but I believe the most info is on the Lunar-Net messageboard
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Re: Koryuu (Composite & S-Video to YPbPr Transcoder) Coming

Post by ldeveraux »

Got my message for ordering the Koryuu today. Excited to give it a go, when do these ship?
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Re: Koryuu (Composite & S-Video to YPbPr Transcoder) Coming

Post by energizerfellow‌ »

SamIAm wrote:Are any specifics about how the Koryuu works known yet?

When I was investigating this stuff a couple of years ago, I remember finding that you could still buy ICs like the M5204FP (though not that one specifically) in bulk from certain suppliers. It looked to me like an enterprising individual could easily pick a bunch of those up, follow the designs in the datasheet exactly, and create a simple CVBS/S-Video converter just like this Koryuu unit (though probably outputting RGB) to sell with very little overhead in parts.

EDIT: Just googling around, they're definitely still available, and for around $3-$4 a pop.
I'm curious as to the chipset IC in this as well as, near as I can tell, analog converters for NTSC/PAL/SECAM are effectively EOL and MIA at this point. You can get quite advanced analog front-ends from the like of TI or Analog Devices, but the output from those is typically something like ITU-R BT.656.
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Re: Koryuu (Composite & S-Video to YPbPr Transcoder) Coming

Post by auberwn »

I've been looking into the M52042FP ic mentioned above.
Between the datasheet pdf, this device which is based on it: http://akizukidenshi.com/catalog/g/gK-00023/ and the fact that the chip is available on aliexpress for a very low price, I think there's more that enough info on how to build a board.
I would be interesting to look into this further.
Does anyone know how can one buy from akizukidenshi.com? The site is a little overwhelming to me. The board has a price of 23euros/25usd. That fair I think.
Does anyone have any more info? Like if this chip is 240p "friendly"? Why wouldn't it though - 15khz in, 15khz out?
Or of any device this is used on which has been tested with 240p?
Btw I see that the M52042FP is the NTSC version - the M52045FP is the pin compatible PAL version.

I'm also interested in Koryuu but in my case the price is a little too much. I'm not saying it's a bad price - just too much for what I might use it for.
I only own an AV Famicom and might buy an Atari 2600 in the future and these are the only two cases where I might use it - unless it also has a good comb filter and works for laserdisc as well but I haven't found any info on that yet.
I am not ruling out buying it in the future - especially if the price goes down a bit.
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Re: Koryuu (Composite & S-Video to YPbPr Transcoder) Coming

Post by megari »

Transcoder ICs working purely in the analog domain tend to be a bit difficult to source reliably enough for mass production. However, the M52042FP (and its PAL counterpart M52045FP) look pretty interesting.

As for the Koryuu, it was designed to scratch an itch, namely, getting a C64 connected to the OSSC. It turns out marqs had done quite a bit of research on the purely analog domain transcoding topic, and based on discussions with him and others, suitable ICs seemed to be scarce, so the approach taken in the Koryuu is a pragmatic one, but not perfect.

The Koryuu uses two Analogue Devices ICs: the ADV7280A performing ADC from CVBS or YC and the ADV7391 to perform DAC to YPbPr. Unfortunately, the ADI chips are not quite as configurable regarding certain details pertaining to sampling as one might hope, but feedback regarding the picture produced by early testers of the Koryuu and its prototypes has been rather positive so far.

The firmware on the Koryuu can be updated using a suitable programmer. The firmware source code as well as sufficient documentation for further development of the firmware will be made available soonish. Many of the features people have asked about are doable, and creating versions of the firmware customized for specific use cases should be quite easy.

The PCB design and detailed schematics are planned to be released at a considerably later point, but due to the unfortunate reality of Chinese cloners and Bucko having made a significant investment in getting the Koryuu generally available to the community, making cloners do a bit more to earn their living is a necessity for now. Designing a PCB from scratch requires a surprisingly large amount of work. However, I am happy to discuss the technical side of the Koryuu in detail, and have the intention to eventually make the design completely free (as in freedom). Please be patient. :)
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kitty666cats
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Re: Koryuu (Composite & S-Video to YPbPr Transcoder) Coming

Post by kitty666cats »

https://www.svideo.com/svc2ypbpr.html

I got this for under $40 recently. It is literally impossible to safely crack open, however xD

NES looked FUCKED but I'm picking up some better 9VDC adapters and am gonna try again. Will also try my LD player soon enough!
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Re: Koryuu (Composite & S-Video to YPbPr Transcoder) Coming

Post by auberwn »

kitty666cats wrote:https://www.svideo.com/svc2ypbpr.html

I got this for under $40 recently. It is literally impossible to safely crack open, however xD

NES looked FUCKED but I'm picking up some better 9VDC adapters and am gonna try again. Will also try my LD player soon enough!
"The board is encapsulated in epoxy that creates a solid, water-proof brick.". You are not kidding that it's impossible to open.
Pity - I'd like to know which IC it uses.

All available, or at least widely available, composite to component/rgb converters/decoders don't play well with 240p. They output 480i even when the input is 240p. The most widely available one for example:
https://videogameperfection.com/2016/02 ... er-review/
I'd be interested to know which chip that device contains.

Before I even heard of Koryuu I purchased my AV Famicom assuming my BVM (a very old model even by CRT standards - a Sony BVM 2016P) would be able to decode the NTSC signal. But my model is actually a PAL one and doesn't contain the NTSC decoder board.
So I looked into those boards (they are called BC (NTSC) and BD (PAL) boards) and they use the TA7193P ic (the NTSC one too even though that ic is specified as a PAL chip) and I was thinking to create a diy board - the schematics are available in the manual. But it requires a lot of additional components and the total just for the components came close to 30-40 euros... That's based on the BVM schematic which contains some parts which probably can be left out. I'm looking into alternate schematics.
It is however as certain to work as possible.
The M52042FP requires a lot less components but I don't know how it handles 240p.
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Re: Koryuu (Composite & S-Video to YPbPr Transcoder) Coming

Post by orange808 »

I've spent a little time with Koryuu and I like it so far. :)

Random observations:

Svideo looks nice. I'm sure of it now, I'm not modding my N64; this looks just fine. Chaining Koryuu through the OSSC yields pretty good results. Any issues I've seen are due to the nature of svideo--not the Koryuuu.

Moving on to composite:

Let's get expectations under control before we go further. The Koryuu is virtually zero latency. There's no frame buffer and the Koryuu isn't being marketed as a home theatre machine. It's a "zero lag" video game transcoder--and it's not a video processor. Laserdisks should be viewed using frame buffered video processing gear.

For what it is, I'm liking the Koryuu. I like the way it balances composite artifacts. All the trademark issues are still present: rainbows, fringing edges, dot crawl, and ringing--BUT: they are balanced well. Great news, Koryuu doesn't simply try to hide everything by smearing the output beyond recognition. It's got a sharp output.

My previous solutions were an XRGB-1, Extron CD 400, or a JVC SVHS.

The XRGB-1 and XRGB-2 are slightly sharper than Koryuu, but they exhibit rainbows that I find distracting. Koryuu makes the rainbows much less annoying (to my eyes) and the slight sharpness tradeoff is worth it.

The JVC was always too soft for games and I prefer the Koryuu. I have a few SVHS decks on hand (Mitsubishi, Sony, and JVC). I prefer Koryuu over all them. The Sony is too soft and there are rainbows. The Mitsubishi is sharp, but the dot crawl is ridiculous and very distracting.

The Extron CD 400 comb filter doesn't impress and it reminds me of the XRGB-1. Koryuu is better. eBay sellers might want to check themselves and mark their over priced ancient junk down to $10 or $20 usd, because Koryuu is better. Koryuu is brand new and reliable--with a working power supply and no old leaking components on the board.

I also have a couple DVD recorders, but thay wouldn't be a fair comparison, because those machines are essentially frame buffered video processors. (Koryuu is low lag.)

Anyhow... I'm liking Koryuu so far. :)
We apologise for the inconvenience
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Re: Koryuu (Composite & S-Video to YPbPr Transcoder) Coming

Post by megari »

orange808 wrote:I've spent a little time with Koryuu and I like it so far. :)

Random observations:

Svideo looks nice. I'm sure of it now, I'm not modding my N64; this looks just fine. Chaining Koryuu through the OSSC yields pretty good results. Any issues I've seen are due to the nature of svideo--not the Koryuuu.

Moving on to composite:

Let's get expectations under control before we go further. The Koryuu is virtually zero latency. There's no frame buffer and the Koryuu isn't being marketed as a home theatre machine. It's a "zero lag" video game transcoder--and it's not a video processor. Laserdisks should be viewed using frame buffered video processing gear.

For what it is, I'm liking the Koryuu. I like the way it balances composite artifacts. All the trademark issues are still present: rainbows, fringing edges, dot crawl, and ringing--BUT: they are balanced well. Great news, Koryuu doesn't simply try to hide everything by smearing the output beyond recognition. It's got a sharp output.

My previous solutions were an XRGB-1, Extron CD 400, or a JVC SVHS.

The XRGB-1 and XRGB-2 are slightly sharper than Koryuu, but they exhibit rainbows that I find distracting. Koryuu makes the rainbows much less annoying (to my eyes) and the slight sharpness tradeoff is worth it.

The JVC was always too soft for games and I prefer the Koryuu. I have a few SVHS decks on hand (Mitsubishi, Sony, and JVC). I prefer Koryuu over all them. The Sony is too soft and there are rainbows. The Mitsubishi is sharp, but the dot crawl is ridiculous and very distracting.

The Extron CD 400 comb filter doesn't impress and it reminds me of the XRGB-1. Koryuu is better. eBay sellers might want to check themselves and mark their over priced ancient junk down to $10 or $20 usd, because Koryuu is better. Koryuu is brand new and reliable--with a working power supply and no old leaking components on the board.

I also have a couple DVD recorders, but thay wouldn't be a fair comparison, because those machines are essentially frame buffered video processors. (Koryuu is low lag.)

Anyhow... I'm liking Koryuu so far. :)
Glad to hear that you like it! :)

I posted a comment regarding the technical side of the Koryuu to this thread earlier, but it went to moderation, apparently, and now seems to have disappeared altogether. Oh well.

The default filter settings on the Koryuu were selected so as not to "ruin the picture", based on feedback from early testers who were of the retro gaming/computer persuasion, and I'm happy that the settings have turned out to be to people's liking so far. :)

The firmware source code as well sufficient documentation for hacking on the firmware will be published soon(tm), so it will be possible to tune the firmware even if the default settings don't quite cut it for you.
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Re: Koryuu (Composite & S-Video to YPbPr Transcoder) Coming

Post by energizerfellow‌ »

So anybody take an inventory of the ICs on this thing yet? A high-res camera pic or flatbed scanner scan of board would be nice.
ldeveraux
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Joined: Thu Mar 01, 2018 10:20 pm

Re: Koryuu (Composite & S-Video to YPbPr Transcoder) Coming

Post by ldeveraux »

energizerfellow‌ wrote:So anybody take an inventory of the ICs on this thing yet? A high-res camera pic or flatbed scanner scan of board would be nice.
Why?
megari
Posts: 24
Joined: Wed Feb 05, 2020 10:30 pm
Location: Europe

Re: Koryuu (Composite & S-Video to YPbPr Transcoder) Coming

Post by megari »

energizerfellow‌ wrote:So anybody take an inventory of the ICs on this thing yet? A high-res camera pic or flatbed scanner scan of board would be nice.
Heh, let me save you some trouble - it's not a secret that the device uses ubiquitous off-the-shelf parts. :D

The video processing is performed by two ICs: the ADV7280A (ADC) and the ADV7391 (DAC). The rest is just to support these two.

I'm on my mobile at the moment, so I'll just end this post by saying that the firmware source code and sufficient technical documentation for further development by community members will be provided soon(tm).
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