February 12, 2018 at 8:10 PM #19241rgdelatoParticipant
The UltraHDMI and the Analogue Super NT have something they call “Hybrid Scanlines”, which seems to lighten sections of the scanline based on the surrounding pixels. Here’s an example picture from RetroRGB:
Is there any chance we could see something like this on the OSSC?February 12, 2018 at 10:31 PM #19250
I think this kind of function requires a framebuffer.February 12, 2018 at 11:37 PM #19257BuckoA51Keymaster
Not necessarily, if Scale2x can be done with just a line buffer, this might be possible too, though it depends how the effect works.
Truth of the matter is though there’s not much space left on the OSSC now for big new features.February 13, 2018 at 6:31 AM #19264haloharryParticipant
Is there any plans of making v2 or 1.5 with lot more space.
Or is it possible to move some files into the sdcard.February 18, 2018 at 2:16 PM #19392
Challenge accepted 😀
I did some testing which uses a very simple way of creating hybrid scanlines so it can be used on the OSSC. What do you think about the results? I like how it has a CRT bloom like side effect.
First is hybrid then normal scanlines.
February 18, 2018 at 3:19 PM #19393
*please link to a bigger pictures.
The completely white region should still have scanlines clearly visible, a more realistic look would be 2 rows white and 1 row black (240p in 720p).
Real scanlines are quite uniform and visible at maximum luminance (white), they gradually get thinner on darker regions.
On a properly calibrated CRT (100 Nit peak luminance) the white color is not overbloomed or ‘connected’ as in your example images.
Here are some photos from my 29″ Sony Trinitron:
Mainly this one:
A great option would be to have the white region and black region scanline strength adjusted independently.
Now lets see how they look in 720 after you fix the white region scanlines. 🙂February 18, 2018 at 4:47 PM #19394HarrumphParticipant
Very nice proof-of-concept! But yeah I agree the darkening should not completely disappear in high luminance sections.February 20, 2018 at 12:44 PM #19433
The example given of the UltraHDMI also has the bright areas without scanlines so I tried to make it look like that in the images I posted. You can increase the scanline strength so that bright areas still have scanlines.
I am using a simple comparison to increase the contrast between dark and bright scanline pixels so its not possible to have the dark areas use 2 scanline and bright areas use 1 scanlines for example. I should probably name this feature Scanline contrast.
I have it running on the OSSC and added a Low and High setting. Here is a comparison on lineX3 with scanline strength set to 100% with contrast Off, Low and High:
Here is a lineX3 capture of scanline strength 81% with contrast High:
https://i.imgur.com/MV2MnHK.pngFebruary 20, 2018 at 3:19 PM #19436
Now this is amazing!
Hope to see this in v0.80.February 20, 2018 at 7:51 PM #19438BuckoA51Keymaster
Did you have to remove any other features or does it all fit in the existing firmware?February 21, 2018 at 12:59 AM #19455
It all fits in the firmware. This feature uses very few resources. SoftCPU which contains the menu among other things is getting low on memory but this just adds 1 menu item in there. The processing is done on the FPGA which Quartus reports has around 54% of logic elements used.February 21, 2018 at 9:11 AM #19458HarrumphParticipant
Individually adjustable scanlines is in the FW improvement roadmap. I don’t know if Marqs already has some code for that.
Hypothetically, could “scanline contrast” be merged with adjustable scanlines, or you think they are mutually exclusive?
If they could be combined, that seems to me almost like the ultimate scanline “sculpting” feature! 🙂February 22, 2018 at 12:15 PM #19475
Yea I am fairly sure they can be combined. I’ll have to wait and see how Marqs changed the scanline code 🙂February 23, 2018 at 11:30 AM #19496JeruroParticipant
Wow! can you share the firmware to test?February 23, 2018 at 6:26 PM #19504SRRAEParticipant
This looks very interesting. It will also help against the image looking so dark when you use heavy scanlines.
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