Hi Farhad,
I understand that you would like to know about the Contourlet decomposition levels in MATLAB and how they are represented by the code snippets nlevels=[0,2,3,4], nlevels=[0,1,3], and nlevels=[2].
Contourlet decomposition is a multi-scale and directional decomposition technique used in image processing to capture the intrinsic geometrical structures of images. It involves applying a Laplacian Pyramid followed by a Directional Filter Bank.
The "nlevels" variable specifies the number of decomposition levels at each scale in the Contourlet transform. Each element in "nlevels" corresponds to a scale, and its value indicates the number of directional subbands at that scale.
For nlevels=[0,2,3,4]:
- The first element 0 indicates no directional decomposition at the coarsest scale.
- The second element 2 indicates 2 directional subbands at the second scale.
- The third element 3 indicates 3 directional subbands at the third scale.
- The fourth element 4 indicates 4 directional subbands at the finest scale.
For nlevels=[0,1,3]:
- The first element 0 indicates no directional decomposition at the coarsest scale.
- The second element 1 indicates 1 directional subband at the second scale.
- The third element 3 indicates 3 directional subbands at the finest scale.
For nlevels=[2]:
- The single element 2 indicates 2 directional subbands at the only scale considered for decomposition.
Refer to the documentation of Contourlet Transform for more details on its properties and usage:
Hope this helps!
