KS4 - Representing Images

Colour depth refers to:

• How many bits are used in a file to store colour information in every pixel
• Resolution divided by the number of colours in an image.
• Degree of file compression applied to an image file.
• Repeated resampling of an image.

Most graphic formats create many colours from:

• Red, green, blue.
• Red, pink, yellow.
• Red, white, blue.
• Black, white, green.

How many colours do we get from 2 bits

• 2 colours
• 4 colours
• 8 colours
• 24 colours

How many colours do we get from 3 bits?

• 2 colours
• 4 colours
• 8 colours
• 24 colours

The higher the resolution, the ____ the file size.

• Smaller
• Larger

The higher the colour depth, the _________the image file size.

• Smaller
• Larger

What is the calculation to work out how many bits a bitmap is?

• height * width * colour depth

• height / width * colour depth

• height - width + colour depth

• height * width / colour depth

What is the calculation to work out how many bytes a bitmap is?

• height * width * colour depth / 8

• height / width * colour depth / 8

• height - width + colour depth / 8

• height * width / colour depth / 8

A bitmap image is 20 pixels high and 5 pixels wide, with a colour depth of 2 bits. How many bits is this image?

• 200 bits

• 100 bits

• 500 bits

• 150 bits

Bitmaps are made up of _______

• Shapes and lines

• Pixels