Image analysis – Applications – Biomedical applications
Reexamination Certificate
1998-12-21
2001-08-07
Mancuso, Joseph (Department: 2721)
Image analysis
Applications
Biomedical applications
C250S455110
Reexamination Certificate
active
06272234
ABSTRACT:
FIELD OF THE INVENTION
This invention relates in general to image processing and relates in particular to contrast adjustment in a laser imager.
BACKGROUND OF THE INVENTION
Laser printers have become widely used in medical imaging to produce hard copy (film) images of electronic medical images derived from a variety of sources (e.g., medical film digitizers, computed and direct radiography, diagnostic imaging modalities—CT, MRI, PET, US). Typically, electronic medical images are processed before printing for various image characteristics, such as contrast, window, level, reverse image, density. A change in contrast changes the code value to density mapping. In existing wet process laser printers, contrast was included in an output look-up-table, taking advantage of the inherent nonlinearity of the printer's code value to density relationship to provide roll-off at low and high densities for contrast greater than 0.
With the advent of dry laser printers, it is desirable to provide greater control over contrast which is greater than zero.
SUMMARY OF THE INVENTION
According to the present invention, there is provided a solution to the problems of the prior art.
According to a feature of the present invention, there is provided a method of processing a digital image comprising the steps of: providing a digital medical image; and processing the digital medical image for contrast as follows: for contrast <0 use a linear function to calculate the entire contrast look-up-table; for contrast 0, the contrast look-up-table is an identity table, and for contrast greater than 0, a linear function is used to calculate the linear region and for regions near D
min
and D
max
, the nonlinear function y=x
n
is used.
ADVANTAGEOUS EFFECT OF THE INVENTION
The invention provides for control of contrast in medical laser printers.
REFERENCES:
patent: 4991093 (1991-02-01), Roberge et al.
patent: 5046118 (1991-09-01), Ajewole et al.
patent: 5172419 (1992-12-01), Manian
patent: 5332898 (1994-07-01), Toro-Lira et al.
patent: 5827942 (1998-10-01), Madsen et al.
Eastman Kodak Company
Mancuso Joseph
Noval William F.
Tabatabai Abolfazl
LandOfFree
Contrast adjustment in a laser imager does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Contrast adjustment in a laser imager, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Contrast adjustment in a laser imager will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2494436