AllCode.py

def windowfn(X):
    return X

def MDCT(X, blocksize=64):
    originalN = len(X)
    N = blocksize

    # zero pad the signal right away. Calls within FFT functions will be
    # effectively ignored.
    nzeros, X = padData(X)

    # Length of padded X
    newN = len(X)
    numBlocks = newN//blocksize

    state = [0]*2*N
    result = []

    # for block in range(0,N,blocksize):
    # for block in X[0:N:blocksize]:
    for i in range(numBlocks):
        temp = windowfn(X[i*N:(i+1)*N])
        state = [0]*2*N

        for i in range(N//2):
            state[i] = -temp[N//2+i] - temp[N//2+i]
            state[N//2+i] = state[N+i] - state[2*N-i-1]

        for i in range(N):
            state[N+i] = temp[i]

        state = DCT4(state)

        result.extend(state[:N])

    return result

def iMDCT(X, blocksize=64):
    # zero padding not done. It is assumed this came from an MDCT
    # and will be correct size

    N = blocksize
    newN = len(X)
    numBlocks = newN//blocksize

    # right now assuming sin windowfn
    normalfactor = N

    state = [0]*2*N
    result = []

    for i in range(numBlocks):
        temp = windowfn(X[i*N:(i+1)*N])

        for i in range(N//2):
            state[i] = -state[N + N//2  -i -1]
            state[N//2 + i] = -state[N + i]

        for i in range(N):
            state[N+i] = temp[i]

        # ? should this be iDCT4, or just DCT4
        state = iDCT4(state)

        for i in range(N//2):
            state[i] = (state[i] + state[N + N//2 +1]) / normalfactor
            state[N//2 + i] = (state[N//2 + i] + state[2*N - i - 1]) / normalfactor

        result.extend(state[:N])

    return result