💣 Notes To Self: What Is an Image?

I write something for myself to remember in the future.

Photo by Markus Spiske on Unsplash

“Sight is what you see with your eyes, vision is what you see with your mind.”- Robert Kiyosaki

How the Eye Works Animation — How Do We See Video — Nearsighted & Farsighted Human Eye Anatomy

📚📖📃Content

1. What is an Image?

2. How Do We See Color?

3. How Do We Digitally Represent a Grayscale Image?

4. How Do We Digitally Represent a Colored Image?

5. What are the types of Digital Image Formats?

What is an Image?

It looks easy to describe what is an image? but most people don’t know what is exactly. First, we should start to think about how do we see images? and what is color? An image is a visual representation of something, while a digital image is a binary representation of visual data. These images can take the form of photographs, graphics, and individual video frames. For this purpose, an image is a picture that was created or copied and stored in electronic form.

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How Do We See Color?

Waves are observed by the human eye and translated in the visual cortex into color. Then, when you look at a banana, the wavelengths of reflected light determine what color you see. The light waves reflect off the banana and hit your eye has a wavelength of 570 to 580 nanometers. These are the wavelength of yellow light.

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How Do We Digitally Represent a Grayscale Image?

A grayscale image is a system of 256 tones with values ranging from 0 to 255. And ‘0’ represents black ‘255’ represents white. So We can think why it is 0 to 255 and that is because of binary code. In binary code ‘0’ means ‘00000000’ and ‘1’ means ‘11111111’ so 8 digits mean 8 bits what a coincidence also 2 power 8 is 256 :) However, starts from 0 and because of it ends at 255. And Pixel represents the smallest part of an image.

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How Do We Digitally Represent a Colored Image?

Each pixel coordinate (x,y) contains 3 layers(values, channel) if colorful. Those layers are RGB(Red, Green, Blue) if you see other colors on the image those are mixed of these three colors.

Sundog Education with Franck Kane

And this is all about mathematics and as you see below this is a one-dimensional matrix and only has white and black.

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And you can imagine an image with 3 layers lined up like below for colorful images.

Python Simplified

What are the types of Digital Image Formats?

Common Image File Formats

1. JPEG (And JPG) — Joint Photographic Experts Group
2. PNG — Portable Network Graphics
3. GIF — Graphics Interchange Format
4. WebP
5. TIFF
6. BMP — Bitmap
7. HEIF — HighEfficiency Image File Format
8. SVG — Scalable Vector Graphics
9. EPS — Encapsulated Postscript
10. PDF — Portable Document Format
11. PSD — Photoshop Document
12. AI — Adobe Illustrator Artwork
13. XCF — eXperimental Computing Facility
14. INDD — Adobe InDesign Document
15. Raw Image File Types

In short, I will try to publish notes to myself about the subjects I have learned recently, the subjects I have repeated, or the subjects I want to write about. If you have a question or something in your mind you can communicate with me on Linkedin.

Keep having fun, developing, and living 🙂