Bits and pixels

A bit is the smallest unit of digital information that a computer can store or transmit. It is a binary digit, which means that it can have only two possible values: 0 or 1.

In computing, a bit is often used as a building block to represent more complex information. For example, eight bits make up a byte, which is commonly used to represent a single character of text or a small number.

Pixels, on the other hand, are the smallest unit of a digital image. They are tiny dots of colour that combine to create a larger image. Each pixel represents a single point in the image and is usually assigned a specific colour value.

The connection between bits and pixels is that the colour of each pixel in a digital image is represented by a binary value that is stored in the computer's memory as a series of bits. The number of bits used to represent each pixel determines the range of colours that can be displayed for that pixel. For example, a pixel represented by 8 bits can display 256 different colour values, while a pixel represented by 24 bits can display over 16 million different colour values.

Let's explore the relationship between bits and pixels in the context of digital images. A digital image is made up of a grid of pixels, with each pixel representing a specific location on the image. The image's resolution is determined by the number of pixels arranged horizontally and vertically. For example, an image with a resolution of 1920x1080 has a width of 1920 pixels and a height of 1080 pixels.

To represent the colour of each pixel, a certain number of bits is allocated. This allocation is referred to as the colour depth or bit depth. The colour depth determines the range and variety of colours that can be assigned to each pixel.

Common colour depths include:

1. 1-bit colour: Each pixel is represented by a single bit, which can have two values (0 or 1). This results in a black-and-white image, where each pixel is either black or white.

2. 8-bit colour: Each pixel is represented by 8 bits, allowing for 256 different colour values. This colour depth is often used in indexed colour images, where a palette of 256 colours is assigned, and each pixel is associated with a specific index in that palette.

3. 24-bit colour: Each pixel is represented by 24 bits, enabling over 16 million different colour values. This colour depth is commonly used in Truecolor images, where each pixel can be assigned a unique RGB (Red, Green, Blue) colour value.

The relationship between bits and pixels is that the colour depth determines the amount of information or detail that can be stored for each pixel. Higher colour depths result in more realistic and accurate colour representations, as they provide a larger number of possible colours to choose from.

One should keep in mind that when the color depth of an image increases, the file size also tends to increase. This is because more bits are required to store the additional color information. As a result, there is a trade-off between color fidelity and file size. Depending on the specific application or use case, different color depths are selected.