sparse image representation via combined transforms - Convex ...

128 CHAPTER 6. SIMULATIONS
• Utilities—supporting files, for example, functions to read images and functions to
analyze results.
• Workouts—scripts to produce results for my thesis and some conference papers.
This package depends heavily on WaveLab [42] and we may integrate it as part of WaveLab.
6.8 Scale of Efforts
This project was started near the end of 1997. 1 Extensive efforts have been spent in the
development of fast code for the edgelet transform and the implementation and adaptation
of iterative algorithms. The code that carries out the edgelet-like transform is completely
written in C, which should give us a tremendous gain in speed for numerical computing.
The formulation of our approach to the minimum l 1 norm problem is new. It is the first
time that LSQR has been implemented for this problem. (Chen, Donoho and Saunders
mention LSQR in their paper, but did not implement it [27].)
1 An unofficial version: We started this project about two years ago. As usual, it was mixed with countless
useful and useless diversions and failures. During the past two years, I have written tens of thousands of
lines of C code and thousands of Matlab functions. There were many exciting and sleep-deprived nights.
Unfortunately, only a small proportion of the effort became the work that is presented in this thesis.