Representing images in binary...

Representing Images in Binary

Computers do not see a picture as colours, they see their binary equivalent. They have a key of binary numbers representing colours, for instance; white = 00, red = 01, blue = 10, purple = 11 and would be shown as 00 01 01 11 01 11 01 00 00 10 11 10 11 00 whereas it would be shown to the user as, e.g. a flower!


Metadata is the extra information a computer needs to create a picture. Due to the computer only seeing the picture as a long string of binary, it needs to know what the dimensions of the picture are, such as the height and width, so that the picture that is created is distinguishable.


Changing the resolution, changes the picture quality. You can increase and decrease the resolution.

Changing the resolution can make a picture more pixelated if you lower the resolution, however, when you try to increase the resolution, it simply makes the image larger as the computer cannot improve the picture because it only sees the pixels as binary.

We would pick a lower resolution because pictures that have a higher resolution have a bigger file size than a lower resolution picture which means it will take up more file storage and, if it’s an internet image, the page it is on will take quicker to download if it is a picture with a lower resolution

Original Picture

Lower Resolution Picture (20ppi)

Higher Resolution Picture (150ppi)

Colour Depth

Changing the colour depth is when you edit how many colours the computer uses when creating the image.

When you lower the colour depth to 4 (2-bit) than the image changes to have less colours which makes the image more distorted and its appearance is worse, on the other hand, increasing the colour depth to 256 (8-bit) makes the image clearer with more colours.

Lower Colour Depth (4 colours)

Higher Colour Depth (256 colours)