← Back to Patent Explorer
US5426684A Expired / Lapsed US ⏱️ 0.0 years remaining

Technique for finding the histogram region of interest for improved tone scale reproduction of digital radiographic images

Assignee: Carestream Health Inc
•
Filing: 1993-11-15
•
Granted: 1995-06-20
•
Expires: 2013-11-15
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract An image processing technique especially useful in processing digital radiographic images. A method for finding a histogram region of interest for improved tone scale reproduction of digital radiographic images includes the following steps. A digital radiographic image is randomly sampled with a sample having an appropriate size to delineate an object of interest. Each sample is processed using texture analysis techniques to extract a plurality of texture features. Using the extracted texture features, each sample is classified with a previously trained neural network classifier to determine its class. Last, the pixel values belonging to the same class are accumulated to form separate histograms for each class. Each of the histograms are then used to optimize tone scale reproduction.

Inventors

  • 👤 Roger S. Gaborski
  • 👤 Lori L. Barski

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-02 16:05
CPC Classifications
G; G06; G06T; G06T5/00; G06T5/40; G06T5/90; G06T5/92; G06T7/00; G06T7/40; G06T7/41; G16; G16H; G16H30/00; G16H30/40; G16H50/00; G16H50/20; G06T2207/00; G06T2207/10; G06T2207/10116; G06T2207/20; G06T2207/20021; G06T2207/30; G06T2207/30004; Y; Y10; Y10S; Y10S128/00; Y10S128/92; Y10S128/925; Y10S378/00; Y10S378/901; Y10S706/00; Y10S706/902; Y10S706/924

Claims Analysis

Total Claims: 10
Claim 1
Independent Claim 103 words
A method of finding a histogram region of interest for improved tone scale reproduction of digital radiographic images comprising the steps of: pseudo-randomly sampling a digital radiographic image with a sample having an appropriate size to delineate a region of interest; processing each sample using texture analysis techniques to extract a plurality of texture features; using the extracted texture features, classifying said sample with a previously trained neural network classifier to determine its class; and accumulating pixel values belonging to the same class to form separate histograms for each said class, wherein each said histogram can be used to optimize tone scale reproduction.
Claim 2
Independent Claim 103 words
A method of finding a histogram region of interest for improved tone scale reproduction of digital radiographic images comprising the steps of: pseudo-randomly sampling a digital radiographic image with a sample having an appropriate size to delineate a region of interest; processing each sample using texture analysis techniques to extract a plurality of texture features; using the extracted texture features, classifying said sample with a previously trained neural network classifier to determine its class; and accumulating pixel values belonging to the same class to form separate histograms for each said class, wherein each said histogram can be used to optimize tone scale reproduction.
Claim 3
Dependent Claim 40 words
The method of claim 1 including the step of segmenting said digital radiographic image into a background region, a foreground region, and an object region of interest, and wherein said sampling step is performed on said object region of interest.
Claim 4
Dependent Claim 15 words
The method of claim 1 wherein said sampling step includes a linear pixel shuffling technique.
Claim 5
Dependent Claim 50 words
The method of claim 1 wherein, before said processing step, each said sample is preprocessed by reducing the digital value of each sample pixel, and performing an adaptive histogram equalization operation on each said sample, and wherein said processing step is performed on the central region of said preprocessed sample.
Claim 6
Dependent Claim 63 words
The method of claim 1 wherein said processing step is performed using a gray-level co-occurrence matrix texture analysis technique to extract a first set of texture features, and also using a neighboring gray-level dependence matrix texture analysis technique to extract a second set of texture features, and wherein said classifying step is performed using said first and said second sets of texture features.
Claim 7
Dependent Claim 41 words
The method of claim 5 wherein said first set of texture features include energy, contrast, correlation, local homogeneity, and entropy, and wherein said second set of texture features include small number emphasis, large number emphasis, number nonuniformity, second moment, and entropy.
Claim 8
Dependent Claim 50 words
The method of claim 6 wherein said first and second sets of features are determined at intersample distances of 1, 2, and 3, such that each set of features include at least fifteen features, and wherein said thirty features are used in said neural network classifier of said classifying step.
Claim 9
Dependent Claim 28 words
The method of claim 1 wherein the histograms of one or more classes can be selectively manipulated to change the tonescale reproduction of said one or more classes.
Claim 10
Dependent Claim 41 words
The method of claim 8 wherein said histograms are of one or more body regions of interest and the tonescales of said one or more body regions can be selectively changed to emphasize said on or more body regions of interest.

References Cited (Backward Citations)

US31847A Cited
US4914295A Cited
US4839807A Cited
US4952805A Cited
US5040225A Cited
US4914589A Cited
US5068788A Cited
US5198669A Cited
US5153926A Cited
US5048097A Cited
US5107529A Cited
US5331550A Cited
US5164993A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1998-06-19 1998-12-19 1999-06-20 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2002-06-19 2002-12-19 2003-06-20 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2006-06-19 2006-12-19 2007-06-20 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag