CE FIT - Contrast Enhancement - FIT the histogram

(10/03/05)

PURPOSE

Finds the linear transformation (applied to pixels) which fits the histogram of the image file to the histogram of the reference file.

SEE ALSO

CE OD [Contrast Enhancement - adjust Optical Densities]
CE GNC [Contrast Enhancement - Graduated Non Convex restoration]
DN MED [Denoise - Median Filtering]

USAGE

.OPERATION: CE FIT

.REFERENCE IMAGE FILE: REFER001
[Enter the name of the reference file.]

.IMAGE TO BE CORRECTED: IMG001
[Enter the name of the input image whose histogram is to be corrected.]

.MASK FOR THE IMAGE TO CORRECTED: MASK999
[Enter the name of the mask file. This file has to have the dimensions equal to the dimensions of the file to be corrected. The non-zero elements indicate 'active' pixels.]

.OUTPUT FILE: OUT001
[Enter the name of the output file. Please note that all the pixels will be transformed according to the linear transformation found for the pixels under the mask.]

NOTES

  1. Reference file does not have to have the dimensions related to the dimensions of the corrected file. Both files can be either 2D or 3D in any combination (for example reference file can be 3D and corrected file 2D). It is reasonable to have more pixels in the reference file.

  2. The reference file should contain the background noise of the micrograph, and the mask should be prepared in such a way that it cuts out any structure from the corrected file. In this way the histograms of the background noise will be matched.

  3. Memory requirements: both files are kept in the memory.

  4. Implemented by Paul Penczek.

  5. Application described in Lambert O., N.Boisset, P.Penczek, J.Lamy, J-Ch.Taveau, J. Frank, J.N.Lamy. Quaternary structure of Octopus vulgaris hemocyanin. J. Mol. Biol. (1994), 238, 75-87.

SUBROUTINES

HISTE

CALLER

UTIL2