OSSC (DIY video digitizer & scandoubler)

[marqs]

Yep, upcoming HDMI 2.1 adds Adaptive Sync / FreeSync! So Variable Refresh Rates are possible with HDMI 2.1. It's called "Game Mode VRR features variable refresh rate".

"HDMI FORUM ANNOUNCES VERSION 2.1 OF THE HDMI SPECIFICATION":
http://www.hdmi.org/press/press_release.aspx?prid=145

That's great news for console games which (excluding VR) aren't likely to jump up from 30-60 fps range anytime soon. PC games I personally prefer to play with higher fps and fixed-interval strobed picture to keep blur minimal

If they'll ever come, how do you guys plan do manage major hardware/software improvements to the current OSSC? Something like an HDMI 2.1 integration, new features that get past actual memory limitations, etc. Would it be possible to provide additional boards/components to attach to the unit, in order to make it more compatible and/or powerful?

I'm probably just looking too forward, but the whole project has been exciting to follow since the very beginning, for me, so it comes quite natural to wonder if the idea behind it is to reach the limits of what it can do at this stage - and then move on to the OSSC2, or whatever its successor will be named - or to expand it beyond its current capabilities, and have a device that basically grows up along with the technology it's meant to support.

You can get a good overview on what's planned for current OSSC hw by looking into roadmap section on the wiki. Profile support (which is pretty much finished) and line4/5x are the remaining major features that you can expect to be added on mainline fw. Then there are features like scaling filters (e.g. eagle) and line offset adjust (for interlaced sources) that are likely to get implemented as alternative firmwares at least initially. It doesn't make much sense to try upgrading current board by duct taping additional components on it. There might still be one new OSSC DIY board revision with audio support for all inputs (required parts and extra 3.5mm connector should be fittable within current PCB/case dimensions), but beyond that we should be looking into completely new hardware to properly implement any advanced features.

But what I don't like is that the OSSC always loads profile 0 on each power cycle. It's a bit user-unfriendly. If I use profile 4 and switch off the OSSC, I expect that profile 4 is loaded again on the next power cycle.

So what I did is: I kept away profile 0 from the user selection and use this slot as a copy of the latest loaded/saved profile. If you like, marqs, I can send you the code changes

I'm a bit wary of erasing/writing flash blocks when user is not explicitly saving settings, but I see your point about usability. I'd rather save last used profile number (not data) in the extra slot that currently contains remote control configuration. That way there's less data to write and smaller risk that a profile slot gets corrupted if unit is powered off at wrong moment. I'll implement that in a few days and upload code to github for evaluation.

Btw. does anybody know if there is PCB mounted female HDMI connectors in existence which would have DVI connector's footprint? I am of course thinking about replacing DVI connector of the OSSC with HDMI connector as adapter adds bulkiness a lot. I think there are none as Googling did not reveal anything... Yeah I should've had bought DIY kit but did not have time back then to do the assembly.

I doubt such HDMI connector assembly. exists.

[borti4938]

Of course... how could I forget about the mem-space behind the one for the profiles. Clearly, a more elegant way than my quick 'n' dirty approach.

[dandiego]

The OSSC unit with the digital audio add-on that was recently reviewed (https://www.videogameperfection.com/201 ... de-review/) apparently can't accept audio input through the 3.5mm jack, only via SCART... But according to the wiki (http://junkerhq.net/xrgb/index.php/OSSC ... dio_output), it should be able to.
Is this a recent firmware and/or hardware change? I plan on getting an OSSC with the audio upgrade once they're available and would like to use the 3.5mm jack for audio input vs. having to purchase a SCART adapter.

[BuckoA51]

That's great news for console games which (excluding VR) aren't likely to jump up from 30-60 fps range anytime soon. PC games I personally prefer to play with higher fps and fixed-interval strobed picture to keep blur minimal

I play most of my PC games on my HDTV just because I like the bigger picture and my surround sound is set up there, so I think this is going to be pretty awesome. Doesn't adaptive sync also reduce input lag in some games? (I usally play vsync on because I find tearing distracting).

Small number of OSSC invites went out, if your number is between 1768 and 1776 check your inbox!

[bobrocks95]

Doesn't adaptive sync also reduce input lag in some games? (I usally play vsync on because I find tearing distracting).

With Freesync, if the framerate is lower than the max refresh rate of the monitor, Freesync is active and you get the reduced lag from having Vsync off, but also no screen tearing. At or above the max refresh rate, it looks at your VSync setting.

[Asbrandt]

Yeah. AdaptiveSync/FreeSync/GSync don't inherently reduce latency themselves, they let you avoid the latency buffered VSync introduces, if you absolutely cannot stand screen tearing.
A high refresh rate monitor does save you a few milliseconds on PC games (thanks to the faster pixel clock) even if the game itself is only running at a lower framerate, but that's not specific to AdaptiveSync/FreeSync/GSync.

[orange808]

The OSSC unit with the digital audio add-on that was recently reviewed (https://www.videogameperfection.com/201 ... de-review/) apparently can't accept audio input through the 3.5mm jack, only via SCART... But according to the wiki (http://junkerhq.net/xrgb/index.php/OSSC ... dio_output), it should be able to.
Is this a recent firmware and/or hardware change? I plan on getting an OSSC with the audio upgrade once they're available and would like to use the 3.5mm jack for audio input vs. having to purchase a SCART adapter.

Well, it's time to say the truth:

That article is a poorly written and cryptic mess.

The audio upgrade is properly described here: https://github.com/borti4938/ossc/tree/ ... /diy-audio

Video Game Perfection needs to sack that article and write a proper replacement. That's an embarrassment.

[BuckoA51]

Well, clearly someone got out of bed on the wrong side today

So how does one feed in audio through the 3.5mm then? I see no option for doing so in the menus.

Edit - NM figured it out, it works but if you have the SCART connector connected it makes the audio fed in via 3.5mm VERY quiet, not great news.

I'd update the review but clearly such an omission by myself is so embarrassing that I just can't face writing ever again. I must "sack" my article (not sure how to do that?) Regalsin himself could probably write more coherently than me.

[Guspaz]

IIRC, the SCART audio pins and the 3.5mm jack are simply connected with no components between them.

[orange808]

Well, clearly someone got out of bed on the wrong side today

So how does one feed in audio through the 3.5mm then? I see no option for doing so in the menus.

Edit - NM figured it out, it works but if you have the SCART connector connected it makes the audio fed in via 3.5mm VERY quiet, not great news.

I'd update the review but clearly such an omission by myself is so embarrassing that I just can't face writing ever again. I must "sack" my article (not sure how to do that?) Regalsin himself could probably write more coherently than me.

Yeah. I let my bad morning ruin yours.

I owe you an apology.

So, I am sorry.

Do you have a SCART switch attached?

[BuckoA51]

Do you have a SCART switch attached?

Yeah, well, Extron Crosspoint.

[Galdelico]

Thanks for replying, marqs. ^_-

[Blair]

semi-pro tip

after testing a bunch of Samsung TV's with the OSSC (line double and line triple modes) I kept having a similar problem with a number of them, no matter what I did I couldn't seem to get even scanlines. even if I threw in an extra video processor like the DVDO's or HD3000.

so I made this discovery.







changing the MPEG noise filter setting seem to fix every television that was giving me trouble, near as I can tell like most TV "enhancement" features it's incredibly broken. especially when "Game Mode" is enabled. (PC mode seems to be the only time this feature actually turns off, but only a few Samsung firmware's have that option).

setting to "auto" seem to yield the best results, and the scanlines looked perfect every time. and unlike the other settings (low, med, high) it didn't change brightness or other values.

for anybody that's having scanline alignment issues try adjusting this setting or any similar setting on your monitor/television. (it might work for other brands and models, please report here or in the videogame perfection forums with your findings)

hope that helps somebody.

[Xyga]

Lol Samsung. I doubt the same thing would be valid with other brands since it really looks uncommon (this setting shouldn't affect scaling that way) and therefore probably a 'bug' created by their engineering.
Still, whatever happens it's a nice find indeed, since Samsung sets showing that uneven scanlines issue are not rare.

[fafangus]

I've got an UE32J6300 (Samsung), seems not be affected, I have to double check that

[BuckoA51]

A trickle of OSSC invites just went out, if you're number 1778 to 1789, check your inbox. This will continue until they're all gone, there's just 5 left. Anyone who misses out will get a 2nd chance in February of course.

[borti4938]

But what I don't like is that the OSSC always loads profile 0 on each power cycle. It's a bit user-unfriendly. If I use profile 4 and switch off the OSSC, I expect that profile 4 is loaded again on the next power cycle.

So what I did is: I kept away profile 0 from the user selection and use this slot as a copy of the latest loaded/saved profile. If you like, marqs, I can send you the code changes

I'm a bit wary of erasing/writing flash blocks when user is not explicitly saving settings, but I see your point about usability. I'd rather save last used profile number (not data) in the extra slot that currently contains remote control configuration. That way there's less data to write and smaller risk that a profile slot gets corrupted if unit is powered off at wrong moment. I'll implement that in a few days and upload code to github for evaluation.

Thank you for the quick implementation. I took a quick look on the profile save/load and it works flawless for me. Also the quick load works well. I haven't tested the 'last input' configuration yet...

IIRC, the SCART audio pins and the 3.5mm jack are simply connected with no components between them.

That's correct. This is also the reason why one can use the 3.5mm jack as an input connector. If someone do so, I suggest to remove the Scart-plugged device.
Intentionally, this is also the reason why someone has the option to swap left and right as the channels are exchanged on Rev. 1.3 OSSC boards at the 3.5mm jack.

The audio upgrade is properly described here: https://github.com/borti4938/ossc/tree/ ... /diy-audio

Thanks for linking to that I have to say that this repository branch is outdated since marqs has included the firmware adaptations to the release branch.
I put the PCBs into a new/separate repository: https://github.com/borti4938/Audio4OSSC

[dandiego]

IIRC, the SCART audio pins and the 3.5mm jack are simply connected with no components between them.

That's correct. This is also the reason why one can use the 3.5mm jack as an input connector. If someone do so, I suggest to remove the Scart-plugged device.
Intentionally, this is also the reason why someone has the option to swap left and right as the channels are exchanged on Rev. 1.3 OSSC boards at the 3.5mm jack.

Have you encountered the low volume issue described below? Any idea if using component video + 3.5mm audio input -- and making sure nothing is plugged in via SCART (AV1) -- would allow for 3.5mm audio input at a normal volume?

From https://www.videogameperfection.com/201 ... de-review/:
"Update – several readers pointed out that it’s also possible to feed in audio via the 3.5mm headphone jack. To do this, simply connect an audio source and make sure there’s no audio being fed in via SCART. Unfortunately, if you have a SCART cable connected to AV1 (even if there’s no signal coming down it), the audio fed in via the 3.5mm connector becomes very quiet."

[borti4938]

It's never a good idea to connect two outputs (one audio source at the 3.5mm jack; the other at the SCART jack) together even if one source is switched off, in my point of view. One might never know what happens... The result depends on how the sources are designed.

If you disconnect one source while using the other you will have the normal behaviour. So it should get the normal volume over the 3.5mm jack.

[Guspaz]

Idea for hardware revision: a place to install an optional two-position switch that connects the audio board to either the 3.5mm or SCART inputs, but features solder bridges that are populated at the factory such that the default is to connect the 3.5mm/scart audio as it is today.

Alternatively, there could simply be solder bridges on the OSSC to split the audio in half (disconnect SCART half and 3.5mm half), and the Borti board is connected to both halves and it handles there being two separate audio inputs.

[Jdurg]

Okay, I'm not sure if this is the right place, and my apology if it is not, but I have been looking into the OSSC for connecting my SNES to my HDMI Receiver/TV. I currently have my SNES connected to a generic SCART to HDMI Converter that goes into my HDMI Switcher which then goes into my AV Receiver and finally the TV. (Yes, that's a lot of steps along the way but magically i cannot notice any lag and love the picture quality).

I only have a modicum of issues with this setup, however. The SCART to HDMI adapter, even when it's not receiving a signal from my SNES, is outputing something to the switcher since it won't automatically switch to the SNES when I turn my Super Nintendo on. (It does auto switch when I turn on my UltraHDMI modded N64 on). Another issue is that the adapter stretches out the SNES image to the full 16:9 format when upscaling to 1080p. While I can just adjust the aspect ratio on my TV, it would be nice if I didn't have to do that and the black borders on the sides could be used to "fill in" the image before sending out via HDMI. The third item is that there are no scanline options available, and while I wouldn't use them all the time I would like to at least have that option.

I understand that the SNES doesn't have the ability to really be modded like the N64 and NES are since I think the video data comes out of the processor as an analog signal and therefore can't be intercepted digitally. So no UltraSNES mod. Heh. (I just recently installed the UltraHDMI mod in my N64 and am super happy that it was simple to install, I was able to handle the fine soldering, and it looks amazing in use).

So I'd like to have a converter/scaler that will output via HDMI in the proper aspect ratio for the SNES, will include audio in the HDMI Stream, and will give me the option to add scanlines all without introducing a ton of lag.

Is the OSSC something that I could put together myself in a DIY kit and achieve this, or would I perhaps be better off waiting to see what Woozle is able to do in his project, or gulp, design a board myself just for the purpose of using in my SNES?

[Guspaz]

Update on 240p GARO on OSSC not syncing, where it syncs on SCART only if the VGA is connected to the GARO, even if VGA is not in use:

I built a VGA terminator for the GARO to see if loading the VGA is what fixed the SCART output. 75 ohm resistors on the R/G/B pins, 2.2 kohm resistors on the H/V sync pins. No luck. Image dims as expected, but OSSC still won't stay sync'd.

Further testing would require a custom VGA cable whereby I try to figure out which VGA pins being connected solves the issue. I had previously verified continuity between the GARO and OSSC ground planes, so I wouldn't think the VGA ground was the issue, but who knows.

Sadly, I don't feel like building a custom VGA cable to test, so I'll probably just live with the workaround.

[marqs]

Idea for hardware revision: a place to install an optional two-position switch that connects the audio board to either the 3.5mm or SCART inputs, but features solder bridges that are populated at the factory such that the default is to connect the 3.5mm/scart audio as it is today.

Alternatively, there could simply be solder bridges on the OSSC to split the audio in half (disconnect SCART half and 3.5mm half), and the Borti board is connected to both halves and it handles there being two separate audio inputs.

There might still be one new OSSC DIY board revision with audio support for all inputs (required parts and extra 3.5mm connector should be fittable within current PCB/case dimensions)

As mentioned above, I'd rather make a revision that has dedicated 3.5mm connectors for AV2 and AV3 (no scart audio passthru), enabling audio support for all inputs without any tricks. I'm not big fan of 3.5mm connectors but there's no space for RCAs on the PCB.

Update on 240p GARO on OSSC not syncing, where it syncs on SCART only if the VGA is connected to the GARO, even if VGA is not in use:

I built a VGA terminator for the GARO to see if loading the VGA is what fixed the SCART output. 75 ohm resistors on the R/G/B pins, 2.2 kohm resistors on the H/V sync pins. No luck. Image dims as expected, but OSSC still won't stay sync'd.

Further testing would require a custom VGA cable whereby I try to figure out which VGA pins being connected solves the issue. I had previously verified continuity between the GARO and OSSC ground planes, so I wouldn't think the VGA ground was the issue, but who knows.

Sadly, I don't feel like building a custom VGA cable to test, so I'll probably just live with the workaround.

Is there any schematic or PCB photo for GARO? It'd help guessing the cause if I knew which parts it uses.

[Guspaz]

I don't believe so, and the chips on the board have also had their markings permanently removed.

I'll ask and see if I can get that information. Another thing I should test is with 240p component from another console. The only thing I can think of that I could produce that with is from my SNES with the HD Retrovision component cables feeding into the GARO.

[Galdelico]

Hey Marqs, hope you don't mind another question, a suggestion from you would be extremely helpful.

Within this week, I'll be buying a new PC monitor, to use exclusively with the OSSC as my one and only 'retro' display. I tested the device on my current Asus 24" (1080p), and it's perfectly compatible with every mode, to the point I'm looking at Asus again, for my upcoming purchase.
Now, I need a 27" for my setup, and I'm wondering whether to stick with a 1080p monitor, or to go 1440p, in LineX4 perspective. Since the difference in price would be quite substantial - and LineX3 (honestly, even LineX2) looks already pretty phenomenal to me - I'm asking you for an opinion on what I should look at. I can't imagine how Line Quadruple mode is gonna look on a 1440 monitor, or if it's going to bring major improvements with interlaced resolutions.

The point is, I don't plan to buy a cheap monitor for the sake of saving a few hundred bucks, but I wouldn't burn 500+ euros for and 'overkill' display, even more considered I wouldn't be using it with a PS4 or a gaming PC.

Thanks in advance!

[JeffreyQ]

Maybe you need to take the video resolution into consideration so that to have a better watching experience. There is a free program that can adjust the regulation with high quality, like transferring 720p to 1080p or vise versa.

[chrono88]

Hello marqs.
480x3=1440p is this possible at some point marqs?
Yeah I know that ossc not support 4k but can it support 1440p?

[marqs]

Within this week, I'll be buying a new PC monitor, to use exclusively with the OSSC as my one and only 'retro' display. I tested the device on my current Asus 24" (1080p), and it's perfectly compatible with every mode, to the point I'm looking at Asus again, for my upcoming purchase.
Now, I need a 27" for my setup, and I'm wondering whether to stick with a 1080p monitor, or to go 1440p, in LineX4 perspective. Since the difference in price would be quite substantial - and LineX3 (honestly, even LineX2) looks already pretty phenomenal to me - I'm asking you for an opinion on what I should look at. I can't imagine how Line Quadruple mode is gonna look on a 1440 monitor, or if it's going to bring major improvements with interlaced resolutions.

The point is, I don't plan to buy a cheap monitor for the sake of saving a few hundred bucks, but I wouldn't burn 500+ euros for and 'overkill' display, even more considered I wouldn't be using it with a PS4 or a gaming PC.

Thanks in advance!

How Line3x/4x/5x:ed 240p sources end up looking on a monitor depends primarily on monitor's scaling, i.e. there shouldn't be an inherent advantage in any of those modes. If you get a 1080p monitor which provides a 1:1 scaling mode, then you should get optimal results from Line4x & 5x. 1:1 mode typically adds some latency, but it should be proportional to the height difference between the mode and the maximum. 1440p would be optimal for Line3x, assuming that scaling from 720p is done properly.

[marqs]

Firmware 0.75 is now officially out, with following changes:

* Added support for up to 10 profiles (incl. menu settings and adv. timing parameters)
* Remote hotkey added for quick profile loading
* Remote hotkeys added for sampling phase adjustment
* Improved remote keymap customization procedure
* Default analog sync LPF set to max
* Diy-audio fw: default TX_mode set to HDMI
* Optionally track last used input and restore it on powerup

As always, instructions and details are found on the wiki

[Galdelico]

How Line3x/4x/5x:ed 240p sources end up looking on a monitor depends primarily on monitor's scaling, i.e. there shouldn't be an inherent advantage in any of those modes. If you get a 1080p monitor which provides a 1:1 scaling mode, then you should get optimal results from Line4x & 5x. 1:1 mode typically adds some latency, but it should be proportional to the height difference between the mode and the maximum. 1440p would be optimal for Line3x, assuming that scaling from 720p is done properly.

Awesome, thanks for taking the time!
That's a good point in 1440p monitors' favour.

And great to see the new firmware is out. Can't wait to be set and ready next week, to finally start to enjoy some gaming.