13 (a) Analog to digital conversion requires two steps: sampling and quantization 0 Explain what is quantization and quantization noise (using illustrations if necessary) () Describe how audio dithering is able to compensate for quantization error Hint: Think about the advantages of the method. (b) Assume you have 12-bit audio samples. You are going to transmit the signal at a bit depth of 6, and expand it back to 12 bits at the recerving end Given an initial 12-bit sample of -600, apply nonlinear companding method to determine the sample value at the receiving end Compute the error in percentage