Hi,
I've got an assignment where I needed to check four types of convolution methods: linear, circular, Overlap add and Overlap save. Convolution performed between low pass filter and audio mp3 file. My assumption was that it shouldn't be any difference between results. However, I've got an errors as following: 1. Between linear and circular convolutions:
Error1_LinConvVSCircConv =
2. Between linear and Overlap save/add convolutions:
Error2_LinConvVSOverlapSave =
Error3_LinConvVSOverlapAdd =
3. Between Overlap Save and Overlap Add convolutions:
Error4_OverlapSaveVSOverlapAdd =
Error estimation was performed by mean percentage absolute error method:
% Error Calculation
Error1_LinConvVSCircConv = abs(mean(abs(pxx1 - pxx2)./pxx1)*100)
Error2_LinConvVSOverlapSave = abs(mean(abs(pxx1 - pxx3)./pxx1)*100)
Error3_LinConvVSOverlapAdd = abs(mean(abs(pxx1 - pxx4)./pxx1)*100)
Error4_OverlapSaveVSOverlapAdd = abs(mean(abs(pxx3 - pxx4)./pxx3)*100)
Comparison was performed in frequency domain. As I mentioned, received error was expected to be 0, and instead I got or very small value or 45%. Was my assumption wrong, or did I make mistake in a code?
