PPG Signal filter validation

I have a noisy PPG signal and I implemented different filters(signal processing techniques) on Matlab to clear the high and low-frequency signal. However, I want to be able to prove if the filter actually works or not. Therefore I am looking to implement the algorithm in Matlab or python to calculate the percentage error between the filtered ppg signal and the ground truth which in this case is the ECG signal. I have the PPG and ECG data collected at the same time in a file.