CRT luminofor fading simulation

Discuss emulation of the Nintendo Entertainment System and Famicom.

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tepples
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Re: CRT luminofor fading simulation

Post by tepples »

Eugene.S wrote:It's the LSD emulator
What does that stand for? Lovely sweet dream?
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Eugene.S
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Re: CRT luminofor fading simulation

Post by Eugene.S »

My Battletoads video
Micro64 PAL and CRT monitor emulation
MAME HLSL CRT Emulator
When you look at CRT Display in dark room... nice glow effect too:
Image
Last edited by Eugene.S on Wed Jun 19, 2013 4:12 pm, edited 3 times in total.
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Zepper
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Re: CRT luminofor fading simulation

Post by Zepper »

I played with pixels and colors a bit here... and looks like a 60hz wouldn't allow that glowing tail. A star that moves on screen would be seen as a trace of it with different brightness, like a .ooOO, and not something really blended.

EDIT: example of what I mean. The brighter palette, the greater the trail.
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example2.png
example.png
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Eugene.S
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Re: CRT luminofor fading simulation

Post by Eugene.S »

Can you show this filter on motion?
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rainwarrior
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Re: CRT luminofor fading simulation

Post by rainwarrior »

I made this a while back:
Image
https://www.youtube.com/watch?v=VSZH0zGz7ho


It's not a good realtime effect though, it's a linear fade with hue shifting subimposing the last few seconds worth of frames under the current one.
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mikejmoffitt
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Re: CRT luminofor fading simulation

Post by mikejmoffitt »

These trails are the right idea, especially since they are spaced and not blended, but the intensity of even the first brightest trail should be much dimmer than the image that produced it.
rainwarrior wrote:I made this a while back:
Image
https://www.youtube.com/watch?v=VSZH0zGz7ho


It's not a good realtime effect though, it's a linear fade with hue shifting subimposing the last few seconds worth of frames under the current one.
Any chance you wanna share that filter? It's pretty neat.
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Zepper
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Re: CRT luminofor fading simulation

Post by Zepper »

Eugene.S wrote:Can you show this filter on motion?
Do you know any software that captures a windowed region of the screen?
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mikejmoffitt
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Re: CRT luminofor fading simulation

Post by mikejmoffitt »

Zepper wrote:
Eugene.S wrote:Can you show this filter on motion?
Do you know any software that captures a windowed region of the screen?
Camstudio can do an okay job sometimes. Microsoft's Expression Encoder is free for ten minutes at a time and does a bit of a better job than Camstudio.
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mikejmoffitt
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Re: CRT luminofor fading simulation

Post by mikejmoffitt »

I have implemented something like phosphors into my game:

Image

It needs a lot of tweaking, but it is not far off from the right idea. It's a little more like a slow LCD simulator, but its blending is additive so a moving black box would not have the effect a moving light box would.

Image

This is the same effect, but tweaked further and with some scanlines. I think it looks pretty decent; I'd say the phosphor trails are generally not very perceivable to the human eye on a real CRT unless the person is using the CRT in the dark, where the lack of external light makes them much more apparent. The above effect looks much like that scenario.
Last edited by mikejmoffitt on Sat Jun 22, 2013 8:50 pm, edited 1 time in total.
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tokumaru
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Re: CRT luminofor fading simulation

Post by tokumaru »

You guys keep posting images, but to actually appreciate these effects we need video!
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mikejmoffitt
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Re: CRT luminofor fading simulation

Post by mikejmoffitt »

tokumaru wrote:You guys keep posting images, but to actually appreciate these effects we need video!
Screen recording software is kind of shit since the stuttering breaks the effect... my game does not have video logging so the best I can do is an actual camera.
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rainwarrior
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Re: CRT luminofor fading simulation

Post by rainwarrior »

mikejmoffitt wrote:These trails are the right idea, especially since they are spaced and not blended, but the intensity of even the first brightest trail should be much dimmer than the image that produced it.

Any chance you wanna share that filter? It's pretty neat.
Well it's not supposed to be a phosphor fade or anything, was just supposed to be some trippy trails.

As for sharing, there's really nothing to share other than the description of what it is. The implementation is something specific to my own video making program (which I will not share), but it's fairly trivial to write if you already have some sort of video processing framework: keep the last X frames, for each output frame just draw each of them in turn (faded and hue shifted) wherever the transparent key colour remains in the image.
tepples
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Re: CRT luminofor fading simulation

Post by tepples »

If you save every frame of raw RGB pixel data to a file as you generate it, you can pipe it through FFmpeg with zero dropped frames.
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mikejmoffitt
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Re: CRT luminofor fading simulation

Post by mikejmoffitt »

tepples wrote:If you save every frame of raw RGB pixel data to a file as you generate it, you can pipe it through FFmpeg with zero dropped frames.
This sounds tedious, unless scripts are readily available with little to no setup that will run on Windows. I am not booting linux for this.
Plus, I am not aware of a function Allegro has that will let me easily save the backbuffer as a file. This sounds like filesystem havoc as too...
rainwarrior wrote:
mikejmoffitt wrote:These trails are the right idea, especially since they are spaced and not blended, but the intensity of even the first brightest trail should be much dimmer than the image that produced it.

Any chance you wanna share that filter? It's pretty neat.
Well it's not supposed to be a phosphor fade or anything, was just supposed to be some trippy trails.

As for sharing, there's really nothing to share other than the description of what it is. The implementation is something specific to my own video making program (which I will not share), but it's fairly trivial to write if you already have some sort of video processing framework: keep the last X frames, for each output frame just draw each of them in turn (faded and hue shifted) wherever the transparent key colour remains in the image.
I see, I don't have any such. I thought it was something you did to FCEUX.

Gosh this looks awful:

http://www.youtube.com/watch?v=rK64l4hA ... e=youtu.be
zzo38
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Re: CRT luminofor fading simulation

Post by zzo38 »

Is it possible with ImageMagick to make something like this?
(Free Hero Mesh - FOSS puzzle game engine)
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