Pixels in Binary

How is a pixel made?

Explain the representation of an image as a series of pixels represented in binary

Each pixel is stored in order as a series of binary digits. The more colours in the image, the more binary you need to represent each pixel. The amount of bits (binary digits) used for each pixel is called the colour depth of the image. With a 1 bit colour depth you can represent two colours (because a bit can be either 0 or 1). With 8 bit colour depth you can have 256 colours. That’s 00000000 to 11111111 in binary. Pictures actually have more colours than you’d expect, so the .jpg format has a colour depth of 24 bits (16777216 colours).

Explain the need for metadata

Metadata is used to determine the height, width and length of an image. It also controls the colour depth and how many colours are in each picture. The metadata may include the type of file it is, .jpeg or .pdf, or the resolution of the image, or when it was taken. In a database, pieces of data may have

metadata attached.

Discuss the effect of colour depth and resolution

The higher the resolution, the more information needs to be stored for an image of any given size. Colour depth is used to describe the maximum number of colours that are used in the image. The higher the number of colours then the more realistic the image will appear. With bitmap images, the chosen colour depth will affect the final file size.