Chapter 1: Information Representation, Multimedia Notes

File Size Calculation:

Q. A picture has been drawn and is saved as a monochrome bitmap image. State how many pixels are stored in 1 byte?

8 pixels

Q. A second picture has a width of 2048 pixels and a height of 512 pixels. It is saved as a 256-color image. Calculate the file size in kilobytes. Show your work.

256 colours = 8-bit depth

= 2048 * 512 * 8

= 8388608 bits (Divide by 8)

= 1048576 bytes (Divide by 1024)

= 1024 kilobytes

Q. Match the representation term to its correct definition.

Pixel: The smallest identifiable component of an image.

Bit Depth: The number of bits used to represent each colour.

Image Resolution: The number of pixels wide by several pixels high.

File Header: Stores data about the image file .e.g file format, number of bits per pixel, and file size.

1.2 Multimedia

Bit-map image:

Important terminology:

• Smallest identifiable picture element that makes up an image.
• Small square of one color.
• Pixels are normally square but can take any shape.