In this problem, we will study the filter banks that are based on the DCT. Use Eq. (6.41a) to implement a $M$-point DCT of $x(n)$ given in Figure 6.31. Assume $M=8$.
a. Give the plots of $|X(k)|$.
b. Also plot the frequency response of the second and third channel analysis filters that are associated with the basis vectors $h_1(n)$ and $h_2(n)$.
c. Plot the impulse response of $h_1(n)$ and see if it is symmetric.
d. Is the DCT filter bank evenly stacked or oddly stacked?