# Human Vision, Color spaces, Transform

### Eyes are such a basic word for us, However it is more profound than just saying it. Eyes are evolved long time ago and today's world a great deal of creatures have complex eyes. Understanding the functioning of eyes contributed a lot to humanbeing and computer vision one of them.

### Why do things have eyes:

* **To see other things!**
* **Visual stimulus is an important signal**
* **Started as photoreceptive protein (eyespots)**

## **How do humans eyes work:**

* **Complex!**
* **Light passes through**
  * **Cornea, humours, lens refract light to focus**
* **Hit the retina**
* **Absorbed by photosensitive cells**
* **Info transmitted through optic nerve, processed by visual cortex**

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### Extra :trophy: : [One of the most famous experiment in physics is the double slit experiment](https://plus.maths.org/content/physics-minute-double-slit-experiment-0)

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:bulb: Light is a combination of waves and objects reflect only some light
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## RGB is a cube

![](https://2797135393-files.gitbook.io/~/files/v0/b/gitbook-legacy-files/o/assets%2F-M99TkJnCKaTvw9u9gQJ%2F-MAR3yZQH69plZ9-d21t%2F-MAR5AP_UI3JX1KWIb9T%2FRGB.png?alt=media\&token=3584a8ba-abd6-4dec-ba43-210e24642354)

## HSV is cylinder

![](https://2797135393-files.gitbook.io/~/files/v0/b/gitbook-legacy-files/o/assets%2F-M99TkJnCKaTvw9u9gQJ%2F-MAR3yZQH69plZ9-d21t%2F-MAR5GLHHc39taTv23L0%2FHSV.png?alt=media\&token=57c8f80c-bba1-4af4-a49d-66179821bccd)

### HUE, SATURATION, VALUE

* **Different model based on perception of light**
* **Hue: what color**
* **Saturation: how much color**
* **Value: how bright**
* **Allows easy image transforms**
  * **Shift the hue**
  * **Increase saturation**