Chapter 1 (1.1, 1.2, 1.3) Data representation Flashcards
What is Pixel
The smallest element used to make up an image on a display.
What is an image
a series of pixels that are converted to binary, which is processed by a computer
What is Colour depth
The number of bits used to represent the colours of a pixel.
What is Image resolution
The total number of pixels that make up an image.
File size of an image
Image resolution * colour depth
What is Sample rate
Number of samples taken per second
What is sampling resolution
The number of bits used to represent sound amplitude in a digital sound recording.
What is lossy compression
The file compression algorithm eliminates unnecessary data from the file. This means the original file cannot be reconstructed once it has been compressed. Eg: MP3, JPEG
What is bit depth
Number of bits used to represent the smallest unit in a sound file
How to calculate file size of a mono sound file
Sample rate * sample resolution * length of sample * number of channels
What are the two types of compression
Lossy
Lossless
What is a bit
Basic computing Element that is either 0 or 1.
What is compression
Reduction in file size by removing or reorganising redundant or repeated pieces of data
What happens when lossy compression is applied
to an img
to a sound file
img - reduce the resolution and/or the bit/colour depth
sound - reduce the sampling rate and/or the resolution.
What is lossless compression
A file compression method that reorganises runs of data to compress the file. The original file can be fully restored.