Colour Depth & Metadata + Image File Size | 2.4 | OCR GCSE Computer Science | J277

7 flashcards

Colour depth: The number of bits used to represent each pixel's colour. e.g. 2 bits (2³) = 8 possible colours 5 bits (2⁵) = 32 possible colours
Describe images with a larger colour depth.: They will have an improved image quality, however the file size will be larger as there are more bits per pixel. More colours can be represented.
Metadata: Additional data about an file to provide further context.
What does metadata include?: - width - height - colour depth - resolution - geolocation - creation date - date file was last edited - file type - file name
What would happen without metadata?: Devices would not be able to display the image on screen as intended.
How do you calculate file size of an image?: resolution x colour depth
Colour Depth & Metadata + Image File Size | 2.4 | OCR GCSE Computer Example: An image has a width of 120 pixels and a height of 210 pixels. It has a colour depth of 6 bits. What is the file size in KB?: 120 x 210 x 6 = 151,200 bits 151,200 / 8 = 18,900 bytes 18,900 / 1000 = 18.9 kB