The Wavelet Digest Homepage
Return to the homepage
Search the complete Wavelet Digest database
Help about the Wavelet Digest mailing list
About the Wavelet Digest
The Digest The Community
 Latest Issue  Back Issues  Events  Gallery
The Wavelet Digest
   -> Volume 5, Issue 2

Web: Steerable Pyramid design data available
images/spacer.gifimages/spacer.gif Reply into Digest
Previous :: Next  
Author Message
Ken Castleman (

PostPosted: Wed Dec 04, 2002 9:49 am    
Subject: Web: Steerable Pyramid design data available
Reply with quote

Web: Steerable Pyramid design data available

I recently added an example of the steerable pyramid transform [1] to
my Web page. The steerable pyramid decomposition uses directional
derivative bandpass filters that have useful shiftability properties
in both position and orientation. It avoids aliasing when
downsampling, effecting a modestly overcomplete representation. It can
be designed to use any number, k, of directional bandpass filters (k =
1 is omnidirectional, k = 2 is bidirectional, etc.).

You can download 17x17 versions of the convolution kernels required to
implement the steerable pyramid transform for k = 1, 2, 3, and 4;
MathCAD(TM) [2] files that compute and plot these kernels and their
transfer functions, and WiT(TM) [3] igraph files that implement the
decomposition and reconstruction of an image.

The Web page also has examples of the 2-dimensional Haar transform
done on a small matrix in MathCAD and on an image in WiT. You can
download these files as well. The page is at:


1. E. P. Simoncelli, W. T. Freeman, E. H. Adelson and D. J. Heeger,
"Shiftable Multiscale Transforms," IEEE Trans. IT-38(2)587-607, March, 1992.
2. Mathsoft, Inc.,
3. Logical Vision, Ltd,

Kenneth R. Castleman, Ph. D.
Perceptive Scientific Instruments, Inc. 713-334-3027 (voice)
2525 South Shore Blvd. Suite 100 713-538-2222 (fax)
League City, TX 77573
All times are GMT + 1 Hour
Page 1 of 1

Jump to: 

disclaimer -
Powered by phpBB

This page was created in 0.025731 seconds : 18 queries executed : GZIP compression disabled