Overlap Add Method is used to calculate the linear convolution of very long signals with finite impulse response. In this method, the long signal is first broken down into smaller parts. These smaller signals are then convoluted with the given h[n]. The result obtained from these convolutions is then added in such a way so as to get the linear convolution of the original signal.
Overlap Save method is similar to Overlap Add method with respect to the splitting of the signal. But the smaller signals are then circularly convoluted with the given h[n] and concatenated in such a way to obtain the final result.
In both the methods, FFT is used to obtain faster calculations
Go to the link below to view the codes for Overlap Add and Overlap Save Method
https://drive.google.com/open?id=0B8OWu2Drhsp0WjJ3SjJoU3RjSkE
In OSM, aliasing is present in first M-1 samples whereas no aliasing effect is present in OAM.
ReplyDeleteYes, you could say that..Also, in OSM, the first sample is not defined. Hence, OAM method is majorly preferred.
DeleteCan oam/osm method be used in filters ?
ReplyDeleteOAM can be used, but OSM.... I'm not quite sure, since the first sample of OSM is not known... So I guess OSM is no that useful for filters
DeleteBoth the methods can be used for FIR filtering
DeleteOAM and OSM requires the same amount of computations and hence same memory space.
ReplyDelete