Representing images, sound and other data Flashcards
Describe analogue signals
A continuous signal, represented usually as a curved wave
Describe digital signals
A discrete signal, represented usually as a stepped wave
What is data?
Values or information
What is an ADC?
Analogue to digital converter, converts an analogue signal to a digital signal
What is a signal?
The electric or electromagnetic impulses that are used to transmit data
What is a DAC?
Digital to analogue converter, converts a digital signal to an analogue signal
What is the main difference between analogue and digital signals.
Analogue is continuous, digital discrete
Why is it not possible to store analogue on a computer system?
It is not discrete.
Name some devices with ADCs in them
Microphone
Digital Camera
What is amplitude
A measure of how large a vibration or velocity is
What is the sample rate?
Rate at which samples are taken, typically measured in kHz.
What is sample resolution.
Bits per sample
What is Nyquist’s theorem?
The rule that sample rate should be at least twice the maximum frequency the human ear can hear
What is MIDI?
A type of file that uses the instructions for how to create each note rather than capture analogue sound waves
When sound is recorded what is measured?
Amplitude
