File Size Reduction (CIE IGCSE ICT)

File size reduction is crucial for storing, sharing, and loading digital images effectively and efficiently

It becomes especially important when dealing with large images or limited storage space

One common way to reduce file size is by reducing the image resolution

• Image resolution refers to the amount of detail an image has
• The higher the resolution, the more pixels the image has, and the larger the file size
• Reducing resolution decreases the number of pixels and therefore reduces file size
• Be aware that reducing resolution can cause a loss of image quality, especially when viewed at larger sizes

Another method to reduce file size is by reducing the colour depth of an image

• Colour depth, also known as bit depth, refers to the number of bits used to represent the colour of a single pixel
• The more bits used, the more colours can be represented, but the larger the file size
• Reducing colour depth means using fewer bits and therefore fewer colours, which can reduce the file size
• Like with resolution, reducing colour depth can lead to a loss of image quality, resulting in an image that looks more "flat" or "posterised"