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Applying the 1-D DWT analysis filterbank in dimension {{math|N1}}, it is now split into two chunks of size {{math| {{frac|N1|2}} × N2 × N3}}. Applying 1-D DWT in {{math|N2}} dimension, each of these chunks is split into two more chunks of {{math|{{frac|N1|2}} × {{frac|N2|2}} × N3}}. This repeated in 3-D gives a total of 8 chunks of size {{math| {{frac|N1|2}} × {{frac|N2|2}} × {{frac|N3|2}}}}. The first chunk is passed via a low pass filter in each of these dimensions and the second one via high-pass.
[[File:Wiki figures1.pdf|thumbnail|The figure depicts 3-D separable DWT procedure by applying 1-D DWT for each dimension and splitting the data into chunks to obtain wavelets for different subbands]]
====Disadvantages of M-D separable DWT====
The wavelets generated by the separable DWT procedure are highly shift variant. A small shift in the input signal changes the wavelet coefficients to a large extent. Also, these wavelets are almost equal in their magnitude in all directions and thus do not reflect the orientation or directivity that could be present in the multidimensional signal. For example, there could be an edge discontinuity in an image or an object moving smoothly along a straight line in the space-time 4D dimension. A separable DWT does not fully capture the same.
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