7 ms·

Blur Busters Open Source Display Initiative – Refresh Cycle Shaders

87 points by NavinF 2y ago

JonathanFly 2y ago
So this a new method that simulates a CRT and genuinely reduces motion blur on any type of higher framerate displays, starting a 120hz. But it doesn't dim the image like black frame insertion which is the only current method that comes close to the clarity of a CRT. But it also simulates other aspects of CRT displays, right? Can you use this method just to reduce blur without reducing brightness, on any game? They mention reducing blur for many things other than retro games in "Possible Use Cases of Refresh Cycle Shaders" but does reducing blur in a flight simulator also make it visually look like a CRT with phosphors?
- delusional 2y ago
  They do mention that it does reduce brightness. The selling point compared to strobing sounds to be less eyestrain. I'd expect it to lose more brightness than strobing, considering the lower relative pixel on time.
vlovich123 2y ago
Does this mean that the original duck hunt gun might work again?
- AnthonBerg 2y ago
  There’s a really interesting discussion of precisely this in the comments under the article! Recommended. Might have to dig to see it.
  - vlovich123 2y ago
    I don’t see any comments under the article. Maybe have to be logged in?
    - paulbgd 2y ago
      It’s on the article before this one. The tldr is that no, this doesn’t reduce latency so there’s no chance of making the original light guns work without modifying either them or the game.
rasz 2y ago
If this is proven to work for 99% people and high refresh displays become cheap GPUs could optimize for rendering just a sliver of screen at a time.
stevage 2y ago
I do not understand at all what this is talking about or why. Is it some elaborate joke? Don't visual effects people go to lots of effort to add motion blur? Why would you want to remove it? Why are they trying to simulate old CRT displays? Can someone explain what this is about?
- martini333 2y ago
  Why exactly do you think motion blur is added?
- fishermanbill 2y ago
  Yeah they are two different effects. Theres motion blur on individual objects that you want (as human eyes see/have) then there is full screen motion blur that is due to the display technology (lcd,oled etc) that you dont want (as human eyes dont see/have). CRTs dont have this motion blur as the screen is blank most of the time - see slo mo guys on youtube for crt displays.
- Springtime 2y ago
  This is about improving motion clarity, so each displayed frame of moving content looks crisp rather than having blur (something that monitors can struggle with even at high refresh rates / high Hz). Most good monitor reviews of high Hz displays (eg: 120Hz+) take fast photographs of moving objects (typically from Blur Busters' 'Test UFO' web page) to demonstrate how good or poorly a monitor handles fast moving content. One technique of significantly improving motion clarity is inserting frames of pure black in the display output (aka BFI, black frame insertion). A downside is some are sensitive to this where it causes eyestrain. This CRT beam simulating shader is said to be similarly effective to BFI at improving motion clarity but with the benefit of reducing eyestrain. However from what I understand the current version is limited to simulating a lower Hz display and requires a higher Hz monitor. All this is distinct from the kind of in-media motion blur that can be enabled in games or seen in recorded video. It's instead about the monitor not being able to render fast moving content clearly enough which leads to non-crisp output frames.
  - stevage 2y ago
saagarjha 2y ago
Past discussion: https://news.ycombinator.com/item?id=42506211 https://news.ycombinator.com/item?id=42506211
fishermanbill 2y ago
We need display manufacturers to provide a refresh cycle that is agnostic of the incoming signal hz sent down the cable AND to either provide shader support (ideally) at the displays hz OR to implement this shader. There really is no need for an expensive RetroTink if we had this. Some manufacturer must be able to do it and the rest would follow.
P_I_Staker 2y ago
Cycle refresh shaders where someting my last team really nailed. The key challenge was during the day there is a lot of sun. Adjustments can be made to the location, it really pays dividents.
nopurpose 2y ago
With about half of the screen is black, can it also boost FPS by not spending GPU time on pixels in those areas if integrated deep into engine?
- kevingadd 2y ago
  You could definitely do this, but a lot of modern rendering techniques rely on having full copies of previous frames lying around, like TXAA, screen-space reflections, etc.
  - rzzzt 2y ago
    The images are briefly persisted and averaged in the back of the viewer's eye.
- Scene_Cast2 2y ago
  I don't think this is how it works. The technique is for when you have X fps content and Y fps capable monitor, where Y > X. In games, you'll still render at your old FPS cap, but this shader is for relatively cheaply generating extra frames that will make the content look smoother / sharper.
fishermanbill 2y ago
Does all this shader really get around is the problem of display inversion? From Gemini: "Display inversion is the process of alternating the voltage between positive and negative for each pixel on an LCD screen to prevent damage. This process is called polarity inversion." If display manufacturers knocked that on the head for certain scenarios then surely we could just have a simple block of horizontal screen scrolling down the display at high refresh rates? Phosphor fall off as far as can be seen in Slo Mo Guys is quite a small effect not on the scale of this shader.
parski 2y ago
I'd buy a new TV or monitor for this feature alone.

87 points by NavinF 2y ago

So this a new method that simulates a CRT and genuinely reduces motion blur on any type of higher framerate displays, starting a 120hz. But it doesn't dim the image like black frame insertion which is the only current method that comes close to the clarity of a CRT. But it also simulates other aspects of CRT displays, right? Can you use this method just to reduce blur without reducing brightness, on any game? They mention reducing blur for many things other than retro games in "Possible Use Cases of Refresh Cycle Shaders" but does reducing blur in a flight simulator also make it visually look like a CRT with phosphors?

delusional 2y ago
They do mention that it does reduce brightness. The selling point compared to strobing sounds to be less eyestrain. I'd expect it to lose more brightness than strobing, considering the lower relative pixel on time.

vlovich123 2y ago

Does this mean that the original duck hunt gun might work again?

AnthonBerg 2y ago
There’s a really interesting discussion of precisely this in the comments under the article! Recommended. Might have to dig to see it.
- vlovich123 2y ago
  I don’t see any comments under the article. Maybe have to be logged in?
  - paulbgd 2y ago
    It’s on the article before this one. The tldr is that no, this doesn’t reduce latency so there’s no chance of making the original light guns work without modifying either them or the game.

rasz 2y ago

If this is proven to work for 99% people and high refresh displays become cheap GPUs could optimize for rendering just a sliver of screen at a time.

stevage 2y ago

I do not understand at all what this is talking about or why. Is it some elaborate joke? Don't visual effects people go to lots of effort to add motion blur? Why would you want to remove it? Why are they trying to simulate old CRT displays? Can someone explain what this is about?

martini333 2y ago
Why exactly do you think motion blur is added?
fishermanbill 2y ago
Yeah they are two different effects. Theres motion blur on individual objects that you want (as human eyes see/have) then there is full screen motion blur that is due to the display technology (lcd,oled etc) that you dont want (as human eyes dont see/have). CRTs dont have this motion blur as the screen is blank most of the time - see slo mo guys on youtube for crt displays.
Springtime 2y ago
This is about improving motion clarity, so each displayed frame of moving content looks crisp rather than having blur (something that monitors can struggle with even at high refresh rates / high Hz). Most good monitor reviews of high Hz displays (eg: 120Hz+) take fast photographs of moving objects (typically from Blur Busters' 'Test UFO' web page) to demonstrate how good or poorly a monitor handles fast moving content. One technique of significantly improving motion clarity is inserting frames of pure black in the display output (aka BFI, black frame insertion). A downside is some are sensitive to this where it causes eyestrain. This CRT beam simulating shader is said to be similarly effective to BFI at improving motion clarity but with the benefit of reducing eyestrain. However from what I understand the current version is limited to simulating a lower Hz display and requires a higher Hz monitor. All this is distinct from the kind of in-media motion blur that can be enabled in games or seen in recorded video. It's instead about the monitor not being able to render fast moving content clearly enough which leads to non-crisp output frames.
- stevage 2y ago

saagarjha 2y ago

Past discussion: https://news.ycombinator.com/item?id=42506211 https://news.ycombinator.com/item?id=42506211

fishermanbill 2y ago

We need display manufacturers to provide a refresh cycle that is agnostic of the incoming signal hz sent down the cable AND to either provide shader support (ideally) at the displays hz OR to implement this shader. There really is no need for an expensive RetroTink if we had this. Some manufacturer must be able to do it and the rest would follow.

P_I_Staker 2y ago

Cycle refresh shaders where someting my last team really nailed. The key challenge was during the day there is a lot of sun. Adjustments can be made to the location, it really pays dividents.

nopurpose 2y ago

With about half of the screen is black, can it also boost FPS by not spending GPU time on pixels in those areas if integrated deep into engine?

kevingadd 2y ago
You could definitely do this, but a lot of modern rendering techniques rely on having full copies of previous frames lying around, like TXAA, screen-space reflections, etc.
- rzzzt 2y ago
  The images are briefly persisted and averaged in the back of the viewer's eye.
Scene_Cast2 2y ago
I don't think this is how it works. The technique is for when you have X fps content and Y fps capable monitor, where Y > X. In games, you'll still render at your old FPS cap, but this shader is for relatively cheaply generating extra frames that will make the content look smoother / sharper.

fishermanbill 2y ago

Does all this shader really get around is the problem of display inversion? From Gemini: "Display inversion is the process of alternating the voltage between positive and negative for each pixel on an LCD screen to prevent damage. This process is called polarity inversion." If display manufacturers knocked that on the head for certain scenarios then surely we could just have a simple block of horizontal screen scrolling down the display at high refresh rates? Phosphor fall off as far as can be seen in Slo Mo Guys is quite a small effect not on the scale of this shader.

parski 2y ago

I'd buy a new TV or monitor for this feature alone.