Color transforms (brightness, contrast, hue) in Computer Vision - Cheat Sheet & Quick Revision

Recall & Review

beginner

What does adjusting brightness in an image do?

Adjusting brightness makes the whole image lighter or darker by adding or subtracting a constant value to all pixels.

beginner

How does changing contrast affect an image?

Changing contrast stretches or shrinks the difference between light and dark areas, making details stand out more or less.

beginner

What is hue in the context of color transforms?

Hue refers to the color type itself, like red, green, or blue. Changing hue shifts all colors around the color wheel.

intermediate

Why do we use color transforms like brightness, contrast, and hue in machine learning?

We use them to make models more robust by showing images in different lighting and color conditions, helping models learn better.

intermediate

How can you adjust brightness and contrast using simple math on pixel values?

Brightness is adjusted by adding a value to pixels; contrast is adjusted by multiplying pixel differences from a midpoint by a factor.

What happens when you increase the brightness of an image?

A The image colors shift around the color wheel

B The difference between light and dark areas increases

C The image becomes lighter overall

D The image becomes blurry

Increasing brightness adds a constant to all pixels, making the image lighter.

Which color transform changes the vividness of colors by stretching differences between light and dark?

A Saturation adjustment

B Brightness adjustment

C Hue adjustment

D Contrast adjustment

Contrast adjustment changes how much light and dark areas differ, affecting vividness.

What does changing the hue of an image do?

A Shifts all colors around the color wheel

B Makes the image lighter or darker

C Increases the sharpness

D Blurs the image

Hue shifts the colors to different points on the color wheel, changing their color type.

Why is adjusting brightness and contrast useful in training machine learning models?

A To create more varied training data

B To reduce image size

C To make images blurry

D To remove colors

Adjusting brightness and contrast helps create varied images so models learn to handle different lighting.

Which operation would you use to make an image darker?

A Add a positive value to pixel brightness

B Subtract a value from pixel brightness

C Shift hue values

D Multiply pixel values by a number greater than 1

Subtracting a value from pixel brightness makes the image darker.

Explain how brightness, contrast, and hue adjustments affect an image and why they are important in machine learning.

Think about how each transform changes the look of an image and why variety helps learning.

Describe a simple way to adjust brightness and contrast using pixel values.

Consider basic math operations on pixel numbers.