Steerable pyramid.

The steerable pyramid, a steerable, multi-scale oriented image transform, is useful for image analysis and synthesis. It has non-aliased sub-bands, which offers advantages over orthogonal wavelet image transforms.

Applications and source code:

Code: Prof. Eero Simoncelli (NYU) has written and made available C and Matlab code and documentation for the steerable pyramid on his steerable pyramid web-page .
Example noise removal application.
Example linear shape from shading application.
Texture synthesis application, by Prof. David J. Heeger (Stanford University) and James R. Bergen (SRI Sarnoff Labs). Abstract and pointer to paper and figures.
Ken Castleman's steerable pyramid web page . With filter taps and algorithm diagram. (Link to his home page. )

References

E. P. Simoncelli and W. T. Freeman, The steerable pyramid: a flexible architecture for multi-scale derivative computation, 2nd Annual IEEE Intl. Conference on Image Processing, Washington, DC. October, 1995. MERL-TR95-15.

E. P. Simoncelli, W. T. Freeman, E. H. Adelson and D. J. Heeger. Shiftable Multi-Scale Transforms. IEEE Trans. Information Theory, Special Issue on Wavelets. Vol. 38, No. 2, pp. 587-607, March 1992. Abstract / Full (1.1M)

W. T. Freeman and E. H. Adelson, The design and use of steerable filters, IEEE Trans. on Pattern Analysis and Machine Intelligence, vol. 13, no. 9, pp. 891 - 906, September, 1991. MIT Vision and Modeling Group TR 126.

H. Greenspan, S. Belongie, R. Goodman, P. Perona, S. Rakshit, and C. H. Anderson, Overcomplete steerable pyramid filters and rotation invariance, Proceedings Computer Vision and Pattern Recognition (CVPR '94), IEEE Computer Society, p. 222 - 228.

D. Shy and P. Perona, X-Y separable pyramid steerable scalable kernels, Proceedings Computer Vision and Pattern Recognition (CVPR '94), IEEE Computer Society, p. 237 - 244.