Kernel vs impulse response what's the difference? [duplicate]

1. What is impulse response in image processing?
2. What is the difference between convolution and multiplication?
3. Why do you flip the kernel?
4. What is impulse response convolution?

What is impulse response in image processing?

In signal processing and control theory, the impulse response, or impulse response function (IRF), of a dynamic system is its output when presented with a brief input signal, called an impulse (δ(t)). More generally, an impulse response is the reaction of any dynamic system in response to some external change.

What is the difference between convolution and multiplication?

d) Convolution is a multiplication of added signals. Explanation: Convolution is defined as weighted superposition of time shifted responses where the whole of the signals is taken into account. But multiplication leads to loss of those signals which are after the limits.

Why do you flip the kernel?

Basically it's because time goes along the x axis with the small time values on the left and the big (later) time values on the right. So if you start shifting in, you're having the big time values hit your signal first, which is not right (causal). So you have to flip it to make the small time values shift in first.

What is impulse response convolution?

Convolution is a very powerful technique that can be used to calculate the zero state response (i.e., the response to an input when the system has zero initial conditions) of a system to an arbitrary input by using the impulse response of a system. It uses the power of linearity and superposition.