Representing Images
Computer Science: KS3, topic 4.1.6
Bitmap
Most digital images are stored as bitmaps.
Bitmap
- A bitmap image is split up into tiny squares called pixels.
- The colour of each pixel is stored as a binary number.
Colour-depth
- The number of bits used to store the colour of each pixel is known as the colour depth.
- The greater the number of bits used to represent each pixel, the more unique colours can be stored.
- Common colour depths are 1-bit, 8-bit, 16-bit, and 24-bit.
Resolution
- Resolution represents the number of pixels in an image.
- The number of pixels is found by multiplying the width by the height of the image.
- An example resolution is 1080p which is 1920x1080.
Metadata
- Metadata is extra information that is added to an image file such as:
- The resolution.
- The colour-depth.
- The encoding format.
- The time and date of taking the photo.