How is color constancy achieved?

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Besides human's not being able to detect UV wavelengths, I understand they also can damage our eyes upon excessive exposure (like during arc welding). How are these wavelengths interacting with the eye to cause it potentially permanent harm? How does color opponency work with non-spectral hues? Is it just the exact opposite on the color wheel, or somewhat less reliable than that? At which level of the visual pathway does the subjective preference for colors arise? Just curious if there have been any study looking into that. It's hard to describe whether everyone percept the a certain color in the same way and quantify subjective parameters to indicate their preference, the question is nontheless interesting to me. We are often shown optical illusions in class where we must focus on a colored "point" or "dot" for a few seconds. When looking at these optical illusions where I must focus on one location, I find it straining for my eyes. I often have to blink or catch my eyes refusing to focus. What causes this

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Besides human's not being able to detect UV wavelengths, I understand they also can damage our eyes upon excessive exposure (like during arc welding). How are these wavelengths interacting with the eye to cause it potentially permanent harm? - PowerPoint PPT Presentation

Transcript of How is color constancy achieved?

Page 1: How is color constancy achieved?

Besides human's not being able to detect UV wavelengths, I understand they also can damage our eyes upon excessive exposure (like during arc welding). How are these wavelengths interacting with the eye to cause it potentially permanent harm?

How does color opponency work with non-spectral hues? Is it just the exact opposite on the color wheel, or somewhat less reliable than that?

At which level of the visual pathway does the subjective preference for colors arise? Just curious if there have been any study looking into that. It's hard to describe whether everyone percept the a certain color in the same way and quantify subjective parameters to indicate their preference, the question is nontheless interesting to me.

We are often shown optical illusions in class where we must focus on a colored "point" or "dot" for a few seconds. When looking at these optical illusions where I must focus on one location, I find it straining for my eyes. I often have to blink or catch my eyes refusing to focus. What causes this

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How is color constancy achieved?

What is the reason for organizing color processing in an opponent fashion?

What happens to color processing after color opponent organization in LGN and V!? Is there a brain location where hues corresponding to color names are coded? Eg wine red, lemon, etc

What is the importance of color for perception? Does it help find things? Identify things?

How good is color discrimination?

Why don’t people know they are color blind?

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Readings for week for – Motion and Stereo

Wolfe Ch 6 and 8

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Low level circuitry in visual cortex (V1/V2) probably responsible for contours and surfaces

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Cooperative interactions betweenV1 cells might also help groupingof line elements to form contours.

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Perceptual Learning is Task Specific

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Neurons in V1 are modified during perceptual learning

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The brain looks for changesacross space – spatial outliers

(similar to the retina)

Detecting outliers depends on learning.

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Figure 4.20 Examples of camouflage

The flip side - camouflage