OSSC (DIY video digitizer & scandoubler)

The place for all discussion on gaming hardware
User avatar
SGGG2
Posts: 747
Joined: Thu Dec 31, 2009 1:03 am
Location: East Coast, US

Re: DIY video digitizer & scandoubler

Post by SGGG2 »

Das Muel wrote:I'm using my XPC-4 to transcode at the moment, but the image from the El Cheapo VGA adapter I've used is not notably worse (and personally I don't need the other features you've referred to). Bear in mind that that particular model (if we do in fact have the same one) is an extremely cheap, generic converter. There are many, many others out there. I think the HDFurys are extortionately priced and there's something of a placebo effect involved, but each to their own.
I only use HDMI transcoding to feed 720p Wii U and 360 signals into a Gefen DVI to VGA Scaler Plus - Brightness is definitely increased, and the colors are washed out, my perception of "softness" could be based on that. Other scenarios might be okay, and perhaps adjusting some settings can compensate, but I can't be arsed to do any further testing. I mean, for $10 you can hardly complain, but if you already have a Fury...
User avatar
marqs
Posts: 1034
Joined: Sat Dec 15, 2012 12:11 pm
Location: Finland

Re: DIY video digitizer & scandoubler

Post by marqs »

deltronik wrote:Here is what my eMachines E211H shows in line triple, I had to set the genesis to 4:3 generic and the nesrgb to 16:9 generic modes to get the correct aspect ratios for each for some reason:

Genesis
Spoiler
Image
NESRGB
Spoiler
Image
The monitor does not detect the modes correctly - the active area is 1280x720.
fafangus wrote:I've got problem with 480i signal (only tested saturn for the moment), the picture is cut in 2, some tips for that ?
Is that using AV3 or AV1, and what's reported if you press 'info'?
ZellSF wrote:I was sure I posted this already:

1: Repeating my request for 240p passthrough, it's not an essential feature but if easy to do would be useful for connecting the OSSC to a scaler that can do better with a unmodified picture that either lacks RGB input or has a terrible A/D stage. Example being connecting to a XRGB-mini. I know there's basically no scaler that fits that criteria, so again not an important feature at all, but if it's easy to implement...?

2: I asked for discrete IR buttons for line3x off and on, while I still think that should be implemented, if you want to conserve IR buttons then having discrete buttons for profiles would be more important. Example being a line2x/scanline profile and a separate line3x profile to easily switch between.
I'll add these to wishlist on wiki, along with N64 de-interpolation feature.
Calle W wrote:I know marqs used the SC-512N1 when he gave us a sneak peak at what the OSSC could do, so maybe he could shed some light on this. Any kind of help would be appreciated.

EDIT: Just took a quick look at the compability spreadsheet and saw this: "SC-512N1 receiver bandwidth set to 125% to avoid dropouts caused by uneven hsync from PPU" from marqs own test of the SNES. I wonder why my setup is giving me weird colors in the same mode.
SC-512N1 has that strange coloring issue if input has 341*5=1705 dots per line, and there seems to be nothing you could do about that (I also tried generating the mode via PC to verify the problem isn't related to OSSC). 256x240 mode using SNES was not stable with my SC-512N1 either.
User avatar
fafangus
Posts: 386
Joined: Fri Jun 01, 2012 6:25 pm
Location: France

Re: DIY video digitizer & scandoubler

Post by fafangus »

marqs wrote:fafangus wrote:
I've got problem with 480i signal (only tested saturn for the moment), the picture is cut in 2, some tips for that ?
Is that using AV3 or AV1, and what's reported if you press 'info'?
lol didn't know there was source info, I'll tell you what it says

Tested in the two inputs (rgbs, yuv for AV1, rgbhv for AV3), maybe it's causing by the CII, but the PS2 is showing her menu in 480i & the pal DQ8 game in 576i, tonight I'll try directly to TV
On Saturn, I have tested DBZ shin (240p to 480i when loading the fight), Digital Pinball (576i), and VF2(480i title screen & ingame & 240p characters selection)

Edit : ok connected roughtly the saturn to the OSSC > works fine !! Great 480i & 576i !!
now I've got to find a way to hook the audio to my setup xp

Bonus : https://youtu.be/YJbu3wtf3mk
Sonic 2 multiplayer ^^
Calle W
Posts: 24
Joined: Sun May 12, 2013 10:38 pm

Re: DIY video digitizer & scandoubler

Post by Calle W »

marqs wrote:SC-512N1 has that strange coloring issue if input has 341*5=1705 dots per line, and there seems to be nothing you could do about that (I also tried generating the mode via PC to verify the problem isn't related to OSSC). 256x240 mode using SNES was not stable with my SC-512N1 either.
Oh yeah, I remember now. I think you wrote that just a few days after I signed up for the device. 1704 and 1706 were fine if I recall correctly. So this should affect the NES as well right? I wonder if the issue is present on the portable versions of the card.

Anyway, thanks for making such a delightful little device. It's by far my best purchase in years!
kardus
Posts: 81
Joined: Sun Dec 20, 2015 4:21 am

Re: DIY video digitizer & scandoubler

Post by kardus »

Is it possible to use the OSSC to output 240p from a 480i component signal?
lui
Posts: 37
Joined: Fri Mar 21, 2014 4:17 am

Re: DIY video digitizer & scandoubler

Post by lui »

ImageImage
ImageImage
ImageImage
Full size images: http://imgur.com/a/oiqzn

Monitor is a BVME250A
PS2 component 240p > OSSC output for the images above. (Scan line strength - 25%)
Unfortunately linetriple does not seem to be working, however the monitor has its own built in linex2 as seen above which can be used in conjunction to produce 960

Also @marqs, I had mistakenly plugged in a JP21 into the scart socket, (as of now everything seems to be working component side) this would not have damaged the ossc by any chance would it?
User avatar
Guspaz
Posts: 3136
Joined: Tue Oct 06, 2015 7:37 pm
Location: Montréal, Canada

Re: DIY video digitizer & scandoubler

Post by Guspaz »

Errm, that's a still-on-the-market $23,400 monitor... and it should support 240p (well, it does 480i) natively... Is the OSSC adding any value there?
ZellSF
Posts: 2642
Joined: Mon Apr 09, 2012 11:12 pm

Re: DIY video digitizer & scandoubler

Post by ZellSF »

I know VGA adapters won't work, but I got one more so I tried it, this one:
http://www.ebay.com/itm/Convertisseur-H ... SwbsBXl1kh
It actually doesn't work with 480p at all. More fun, if you connect it it turns on the OSSC's power LED and display backlight. So yeah, don't get this adapter.
Guspaz wrote:Errm, that's a still-on-the-market $23,400 monitor... and it should support 240p (well, it does 480i) natively... Is the OSSC adding any value there?
Didn't he more or less write that? He uses OSSC's linedouble in combination with his display's 2X function for a 4X scale.
User avatar
Das Muel
Posts: 140
Joined: Tue Feb 03, 2015 7:50 pm
Location: Manchester, UK
Contact:

Re: DIY video digitizer & scandoubler

Post by Das Muel »

Still slightly confused by the Dreamcast aspect ratio thing. When I set the OSSC to DTV for 480p, the image is fantastic but the aspect ratio is squished on a 16:9 display. If I set to VGA, it is in the correct ratio but the sampling is a little messed-up. Is there any way around this other than adjusting with another processor?

*Edit: If I convert the OSSC's DVI into VGA, feed it into my XPC-4 and pass it through (unprocessed) to my TV, the aspect ratio is correct. Weird. Loving how you can get PC CRT-style thin scanlines with the 480pX2 feature.
I am the geezer from the Retro Muel Channel:
https://www.youtube.com/channel/UCIg73A ... u89QcCBD3A
User avatar
Fudoh
Posts: 13015
Joined: Mon Mar 06, 2006 3:29 am
Location: Germany
Contact:

Re: DIY video digitizer & scandoubler

Post by Fudoh »

If I convert the OSSC's DVI into VGA, feed it into my XPC-4 and pass it through (unprocessed) to my TV
can't you connect the OSSC via DVI-D to DVI-D to the XPC-4 and still get VGA from it ? Or just not unprocessed any longer ?

The whole input sampling on the Dreamcast has been discussed a lot, but it's hardly understood. I *think* THIS explains it about right. Point being that even VESA sampling doesn't get the AR right (and you're losing resolution on top of it). The lower part (OSSC in VESA sampling mode) is also what happens on all TVs with VGA input, most LCD monitors with VGA inputs and all the cheap VGA to HDMI converters out there.

Image
User avatar
pyrotek85
Posts: 214
Joined: Fri May 25, 2012 8:34 pm

Re: DIY video digitizer & scandoubler

Post by pyrotek85 »

Yikes, what did you do Sega? lol
User avatar
Fudoh
Posts: 13015
Joined: Mon Mar 06, 2006 3:29 am
Location: Germany
Contact:

Re: DIY video digitizer & scandoubler

Post by Fudoh »

on a CRT (and with this on all Naomi cabs) this isn't a problem at all since there's no digital sampling applied and you can adjust the AR till it fits the screen.

Converters with a frame buffer (XPC-4, Gefen Scaler and others) can sample the input correctly with DTV timings and then "re-package" the UNSCALED image into a VESA timing 640x480 output. This way LCDs can display a correct 1,33:1 aspect ratio for the Dreamcast's active image area. The OSSC v2 will certainly be able to do the same :mrgreen:
CobraKing
Posts: 166
Joined: Thu Mar 31, 2016 4:07 pm

Re: DIY video digitizer & scandoubler

Post by CobraKing »

^^
Hold up, there's a V2 on the way already? I think there's less than 100 people who actually have the V1! :lol:
User avatar
Fudoh
Posts: 13015
Joined: Mon Mar 06, 2006 3:29 am
Location: Germany
Contact:

Re: DIY video digitizer & scandoubler

Post by Fudoh »

no, sorry. Didn't mean to confuse anybody. You can call it wishful thinking from my side :lol:
User avatar
Unseen
Posts: 723
Joined: Sun May 25, 2014 8:12 pm
Contact:

Re: DIY video digitizer & scandoubler

Post by Unseen »

Fudoh wrote:The OSSC v2 will certainly be able to do the same :mrgreen:
I think it could be implemented on the current hardware, but it would need some PLL trickery to get the timing right. Alternatively you could sample the signal with DTV timing and output only 640 active pixels on the output, but that would be a non-standard video signal (720x480 timing with larger horizontal front-/backporch)
meneerbeer
Posts: 50
Joined: Thu Mar 26, 2015 9:14 am

Re: DIY video digitizer & scandoubler

Post by meneerbeer »

Unseen wrote:
Fudoh wrote:The OSSC v2 will certainly be able to do the same :mrgreen:
I think it could be implemented on the current hardware, but it would need some PLL trickery to get the timing right. Alternatively you could sample the signal with DTV timing and output only 640 active pixels on the output, but that would be a non-standard video signal (720x480 timing with larger horizontal front-/backporch)
What is the advantage of converting it to VESA? Just so you will not have borders in 16:9?
User avatar
Fudoh
Posts: 13015
Joined: Mon Mar 06, 2006 3:29 am
Location: Germany
Contact:

Re: DIY video digitizer & scandoubler

Post by Fudoh »

it would give you a proper 4:3 ratio (1.33:1) instead of 1.25:1 or 1.18:1 in the samples above.
meneerbeer
Posts: 50
Joined: Thu Mar 26, 2015 9:14 am

Re: DIY video digitizer & scandoubler

Post by meneerbeer »

Fudoh wrote:it would give you a proper 4:3 ratio (1.33:1) instead of 1.25:1 or 1.18:1 in the samples above.
Does 720x480p on an LCD then assume non square pixels?

Otherwise, I do not see how it does not result in a 4:3 ratio. If you would display 720x480p with square pixels, but only having an active image of 640x480 (so padded with black borders) you would have a proper 4:3 ratio, right?
User avatar
Fudoh
Posts: 13015
Joined: Mon Mar 06, 2006 3:29 am
Location: Germany
Contact:

Re: DIY video digitizer & scandoubler

Post by Fudoh »

Does 720x480p on an LCD then assume non square pixels?
yes, always. It's either 4:3 or 16:9, but not 3:2 (which would assume square pixels).
If you would display 720x480p with square pixels, but only having an active image of 640x480 (so padded with black borders) you would have a proper 4:3 ratio, right?
right, but show me a display which can do that!
meneerbeer
Posts: 50
Joined: Thu Mar 26, 2015 9:14 am

Re: DIY video digitizer & scandoubler

Post by meneerbeer »

Fudoh wrote:
Does 720x480p on an LCD then assume non square pixels?
yes, always. It's either 4:3 or 16:9, but not 3:2 (which would assume square pixels).
If you would display 720x480p with square pixels, but only having an active image of 640x480 (so padded with black borders) you would have a proper 4:3 ratio, right?
right, but show me a display which can do that!
This is rather interesting. Wouldn't the GameCube suffer from this problem too? Afaik, it uses 858 pixels per line, but usually games have an active resolution of less than 720x480. Or does GameCube already assume non square pixels, whereas Dreamcast assumes square pixels?

Also, what about interlaced mode on Dreamcast. Same problem?
User avatar
marqs
Posts: 1034
Joined: Sat Dec 15, 2012 12:11 pm
Location: Finland

Re: DIY video digitizer & scandoubler

Post by marqs »

Unseen wrote:
Fudoh wrote:The OSSC v2 will certainly be able to do the same :mrgreen:
I think it could be implemented on the current hardware, but it would need some PLL trickery to get the timing right. Alternatively you could sample the signal with DTV timing and output only 640 active pixels on the output, but that would be a non-standard video signal (720x480 timing with larger horizontal front-/backporch)
800/858 ratio cannot be exactly achieved with Cyclone IV PLL, so a dedicated horizontal genlock PLL (freely selectable divisor using hsync reference) would be needed. Similar operation in vertical direction would allow setting the number of output scanlines which would greatly increase compatibility.

Marking the active length to 640 in 858-pixel scanline will be possible with current HW when timing tweaker gets implemented, but display compatibility will be probably on par with linetriple.
meneerbeer
Posts: 50
Joined: Thu Mar 26, 2015 9:14 am

Re: DIY video digitizer & scandoubler

Post by meneerbeer »

marqs wrote:
Unseen wrote:
Fudoh wrote:The OSSC v2 will certainly be able to do the same :mrgreen:
I think it could be implemented on the current hardware, but it would need some PLL trickery to get the timing right. Alternatively you could sample the signal with DTV timing and output only 640 active pixels on the output, but that would be a non-standard video signal (720x480 timing with larger horizontal front-/backporch)
800/858 ratio cannot be exactly achieved with Cyclone IV PLL, so a dedicated horizontal genlock PLL (freely selectable divisor using hsync reference) would be needed. Similar operation in vertical direction would allow setting the number of output scanlines which would greatly increase compatibility.
You can cascade two PLLs. Probably even more if necessary, but your clock jitter might become too much.
User avatar
Fudoh
Posts: 13015
Joined: Mon Mar 06, 2006 3:29 am
Location: Germany
Contact:

Re: DIY video digitizer & scandoubler

Post by Fudoh »

This is rather interesting. Wouldn't the GameCube suffer from this problem too? Afaik, it uses 858 pixels per line, but usually games have an active resolution of less than 720x480. Or does GameCube already assume non square pixels, whereas Dreamcast assumes square pixels?
first of all the GC doesn't output in RGBHV, but in component (or HDMI with a mod) and with component (or HDMI) a TV never assumes a VESA timing. Also the Cube assumes 720x480p to be 4:3 and uses it accordingly, while the DC (and that's the actual problem) assumes a square pixel ratio (your 3:2 -> 4:3 theory from above) and considers the borders between 640x480 and 720x480 to be overscan.
lui
Posts: 37
Joined: Fri Mar 21, 2014 4:17 am

Re: DIY video digitizer & scandoubler

Post by lui »

ImageImage
ImageImage
ImageImage
ImageImage
http://imgur.com/a/5UBIw


Component 480i comparison
Left is 480i output via OSSC, right is 480i component output directly to the monitor via input card
Guspaz wrote:-
It is essentially as zell had said. Although, the OSSC is considerably less expensive than the input card that is required for RGB/Component.

Is there any benefit to the "even scanline" setting? As "odd" provides an extra line of signal
User avatar
LDigital
Posts: 341
Joined: Sun Jan 17, 2016 9:15 am

Re: DIY video digitizer & scandoubler

Post by LDigital »

What is x3 mode supposed to look like? When I use it for 240p stuff it just makes a super sharp small image in the center of the screen. It's not terribly big and I usually play on a 55 inch HD screen
User avatar
Fudoh
Posts: 13015
Joined: Mon Mar 06, 2006 3:29 am
Location: Germany
Contact:

Re: DIY video digitizer & scandoubler

Post by Fudoh »

in terms of visible height it should look identical to 480p output. Maybe your display treats it differently because it doesn't detect it as a ED/HD resolution. But you should have zoom controls available somewhere nevertheless.
User avatar
parodius
Posts: 720
Joined: Wed Jan 26, 2005 5:54 am
Location: Singapore

Re: DIY video digitizer & scandoubler

Post by parodius »

I don't know if this has been reported, but with FW 0.71 there is a bug on using odd horizontal scanlines with lineX3 mode.
Scanline will be set on the 2nd line instead of the 3rd line as expected.

Also, while I tested some arcade PCBs (M92, System 18, Toaplan V2, SPI) I had only 1 issue : the SPI gave me a black screen (on a BenQ G2400W) without any red led, either through AV1 RGBS or AV3 RGBHV (through Sync Strike), the only way to make it work was to upscale it first to 31khz (Micomsoft DISPL to AV3 RGBHV).

Note : this is minor and performance/features have been nothing but stellar since I started using OSSC.
My sales thread : 2020/07/20..MASTER.VER.
User avatar
ceramiclion
Posts: 55
Joined: Thu Dec 22, 2011 11:39 pm

Re: DIY video digitizer & scandoubler

Post by ceramiclion »

I got my OSSC today and I have been having an issue that I haven't read here yet.
When I use the SNES (while playing MegaMan X3) I get an issue that when I shoot a charged up shot the screen desyncs and goes back for a second. I tried on 3 tvs and all did this. I then hooked it up with my DVDO Edge and it does the same thing...
So then I hooked it up with my sync strike and it works fine even in line trippler mode...
The genesis works perfectly.
The PSX however is having the same issue on SCART as the SNES on Symphony of the night.
Is this normal?

Thank you.
ZellSF
Posts: 2642
Joined: Mon Apr 09, 2012 11:12 pm

Re: DIY video digitizer & scandoubler

Post by ZellSF »

ceramiclion wrote:I got my OSSC today and I have been having an issue that I haven't read here yet.
When I use the SNES (while playing MegaMan X3) I get an issue that when I shoot a charged up shot the screen desyncs and goes back for a second. I tried on 3 tvs and all did this. I then hooked it up with my DVDO Edge and it does the same thing...
So then I hooked it up with my sync strike and it works fine even in line trippler mode...
The genesis works perfectly.
The PSX however is having the same issue on SCART as the SNES on Symphony of the night.
Is this normal?

Thank you.
Have you tried increasing sync lpf in OSSC's settings?
User avatar
marqs
Posts: 1034
Joined: Sat Dec 15, 2012 12:11 pm
Location: Finland

Re: DIY video digitizer & scandoubler

Post by marqs »

meneerbeer wrote:You can cascade two PLLs. Probably even more if necessary, but your clock jitter might become too much.
Yes, it's possible to get exact 800/858 ratio by cascading 2 PLLs (e.g. (40/78)*(20/11)) but it's not a generic solution which works for every ratio.
parodius wrote:I don't know if this has been reported, but with FW 0.71 there is a bug on using odd horizontal scanlines with lineX3 mode.
Scanline will be set on the 2nd line instead of the 3rd line as expected.
Good note - I'll add that to bug list.
parodius wrote:Also, while I tested some arcade PCBs (M92, System 18, Toaplan V2, SPI) I had only 1 issue : the SPI gave me a black screen (on a BenQ G2400W) without any red led, either through AV1 RGBS or AV3 RGBHV (through Sync Strike), the only way to make it work was to upscale it first to 31khz (Micomsoft DISPL to AV3 RGBHV).
SPI (Viper Phase 1) worked on an old fw so I'll need to check that again when I have a chance.
ceramiclion wrote:I got my OSSC today and I have been having an issue that I haven't read here yet.
When I use the SNES (while playing MegaMan X3) I get an issue that when I shoot a charged up shot the screen desyncs and goes back for a second. I tried on 3 tvs and all did this. I then hooked it up with my DVDO Edge and it does the same thing...
So then I hooked it up with my sync strike and it works fine even in line trippler mode...
The genesis works perfectly.
The PSX however is having the same issue on SCART as the SNES on Symphony of the night.
Is this normal?
Those are usually signs of a low quality cable which has insufficient shielding, but you can try setting sync LPF to max and possibly reduce sync vth to see if it helps.
Post Reply