Code in python

1.2 1.1 (3p) Sub-band coding is beneficial when different quantization errors are acceptable for different fre- quency ranges. In this problem you shall implement a simple sub-band coding scheme as follows: 1. Load an 16k audio signal, e.g., the one we usually use in the exercises. 2. Make a low pass and a high pass filter with cut-off frequency 4kHz. You can use code snippets from the exercises. 3. Filter the signal with the two filters so that you obtain one signal containing frequencies be- low 4kHz and one signal containing frequencies above 4kHz. (There will be no frequencies higher than 8kHz since the orginal signal is sampled 16kHz and we assume it was filtered appropriately for this. ) 4. Downsample the two signals to the lowest sampling rate that is possible without introducing alias effects. 5. Quantize the signal with 8 bits for the low frequency signal and with 4 bits for the high frequency signal. You can use quantization functions from the previous HW. 6. Reconstruct the original signal, i.e., upsample the two signals again (be careful to apply the appropriate filtering afterwards) and merge them