US6424730B1 — Medical image enhancement method for hardcopy pri…

Claim 1

Independent Claim 172 words

A method for the enhancement of medical images for hardcopy prints comprising the steps of: obtaining a medical image having a shadow region and a highlight region in digital format; conducting a plurality of operations for Human Visual System (HVS)-based edge enhancement with each operation having a uniquely specified high frequency amplification function and range such that edges are more enhanced in the shadow region than in the highlight region; adjusting image tone scale, for reflection prints increase the contrast in the shadow region and decrease the contrast in the highlight region, and for transparency prints decrease the contrast in the shadow region and increase the contrast in the highlight region; sending the processed image to an output device for producing hardcopy prints; and wherein said conducting step is based on P n−1 =L n +α n *H n , and wherein L n and H n are the respective low frequency and high frequency components of image P n at processing step n, α n is the amplification function and n≧0.

Claim 2

Independent Claim 172 words

A method for the enhancement of medical images for hardcopy prints comprising the steps of: obtaining a medical image having a shadow region and a highlight region in digital format; conducting a plurality of operations for Human Visual System (HVS)-based edge enhancement with each operation having a uniquely specified high frequency amplification function and range such that edges are more enhanced in the shadow region than in the highlight region; adjusting image tone scale, for reflection prints increase the contrast in the shadow region and decrease the contrast in the highlight region, and for transparency prints decrease the contrast in the shadow region and increase the contrast in the highlight region; sending the processed image to an output device for producing hardcopy prints; and wherein said conducting step is based on P n−1 =L n +α n *H n , and wherein L n and H n are the respective low frequency and high frequency components of image P n at processing step n, α n is the amplification function and n≧0.

Claim 3

Dependent Claim 49 words

The method according to claim 1 wherein said medical image is obtained from a variety of modalities of medical imaging, including, but not limited to, one of the following: Computed Radiography, Direct Radiography, radiographic digitizer, Computed Tomography, Magnetic Resonance Imaging, Ultrasound Imaging, Nuclear Imaging, digital angiography, and digital fluorography.

Claim 4

Dependent Claim 28 words

The method according to claim 1 wherein said medical image in digital format is in film optical density space, including, but not limited to, scaled optical density space.

Claim 5

Dependent Claim 30 words

The method according to claim 1 wherein said obtaining step includes converting a digital image to the film optical density space using a transform curve as in FIG. 3 .

Claim 6

Dependent Claim 38 words

The method according to claim 1 wherein said high frequency amplification function and range are determined by the human visual system, as well as medical imaging modality, diagnostic region of interest and the characteristics of the output device.

Claim 7

Dependent Claim 34 words

The method according to claim 1 wherein said amplification is performed in such a way that said high frequency range is emphasized more in the image shadow region than in the image highlight region.

Claim 8

Dependent Claim 63 words

The method according to claim 1 wherein the low frequency and high frequency components are obtained using a convolution filter, including but limited to a linear convolution filter and a non-linear convolution filter. The linear convolution filter includes but is not limited to a high-pass filter such as a Laplacian filter, and a low pass filter such as a rectangle uniform convolution filter.

Claim 9

Dependent Claim 23 words

The method according to claim 7 wherein the kernel shape is based on K x K y = P y P x .

Claim 10

Dependent Claim 26 words

The method according to claim 7 wherein the kernel size is based on imaging modality, diagnostic regions of interest and the characteristics of the output device.

Claim 11

Dependent Claim 22 words

The method according to claim 7 wherein the low frequency and high frequency components are obtained using 7 an image decomposition method.

Claim 12

Dependent Claim 37 words

The method according to claim 1 wherein the amplification function α n is a function of the low frequency image component L n and it monotonically increases as L n changes from highlight region to shadow region.

Claim 13

Dependent Claim 33 words

The method according to claim 1 wherein the amplification function α n is a function of image P n and it monotonically increases as P n changes from highlight region to shadow region.

Claim 14

Dependent Claim 33 words

The method according to claim 1 wherein the amplification function α n is a function of image P n and it monotonically increases as P n changes from highlight region to shadow region.

Claim 15

Dependent Claim 75 words

The method according to claim 1 wherein the amplification function α n is based on α n = α min + ( α max - α min ) · L n - L min L max - L min ; wherein d min and d max are respectively the minimum and maximum values of d and L min and L max are respectively the minimum and maximum values of L n the low frequency component.

Claim 16

Dependent Claim 15 words

The method according to claim 1 wherein the amplification function α n is a constant.

Claim 17

Dependent Claim 84 words

The method according to claim 1 wherein said conducting step is based on P n + 1 = L 0 + ∑ i = 0 n   [ α n · H n ] ; where n≧0 is the index for processing steps; L 0 is the low frequency component of the original image 0 ; H n is the high frequency component of image 0 at processing step n; P n+1 is the resulting image; and α n is the amplification function.

Claim 18

Dependent Claim 63 words

The method according to claim 16 wherein the low frequency and high frequency components are obtained using a convolution filter, including but limited to a linear convolution filter and a non-linear convolution filter, wherein the linear convolution filter includes, but is not limited to, a high-pass filter such as a Laplacian filter, and a low pass filter, such as a rectangle uniform convolution.

Claim 19

Dependent Claim 49 words

The method according to claim 18 using a kernel shape is based on K x K y = P y P x ; where P x and P y are the pixel width and pixel height, respectively; K x and K y are the kernel width and height, respectively.

Claim 20

Dependent Claim 27 words

The method according to claim 17 using a kernel size which is based on imaging modality, diagnostic regions of interest and the characteristics of the output device.

Claim 21

Dependent Claim 26 words

The method according to claim 7 wherein the low frequency and high frequency components are obtained using the image decomposition method as in FIG. 2 .

Claim 22

Dependent Claim 37 words

The method according to claim 16 wherein the amplification function α n is a function of the low frequency image component L 0 and it monotonically increases as L 0 changes from highlight region to shadow region.

Claim 23

Dependent Claim 40 words

The method according to claim 16 wherein the amplification function α n is based on α n = α min + ( α max - α min ) · L 0 - L min L max - L min .

Claim 24

Dependent Claim 15 words

The method according to claim 16 wherein the amplification function α n is a constant.

Claim 25

Dependent Claim 157 words

The method according to claim 1 wherein said adjusting image tone scale step uses a function which is based on the derivation based on: log   L I = a + c · ln   I + e · ( ln  I ) 2 + g · ( ln   I ) 3 + j · ( ln   I ) 4 1 + b · ln   I + d · ( ln   I ) 2 + f · ( ln   I ) 3 + h · ( ln   I ) 4 + k · ( ln   I ) 5 ; L ( D )= L 0 ·10 −D ; l ( d )= l 0 ·10 −D ; jnd - jnd min jnd max - jnd min = JND - JND min JND max - JND min ;  and D→L(D)→JND(L)→jnd(l)→l(d)→d.

Claim 26

Dependent Claim 35 words

The method according to claim 1 wherein said adjusting tone scale step for reflection prints uses a function which increases the image contrast in the shadow region while decreases the contrast in the highlight region.

Claim 27

Dependent Claim 35 words

The method according to claim 1 wherein said adjusting tone scale step for transparency prints uses a function which decreases the image contrast in the shadow region while increases the contrast in the highlight region.

Claim 28

Dependent Claim 60 words

The method according to claim 1 wherein said adjusting tone scale step for transparency prints uses a function which is based on  T  ( D )  D  D = D2 ≥  T  ( D )  D  D = D1 ≥ 0 , where D 1 <D 2 ; and D is density.

Claim 29

Dependent Claim 60 words

The method according to claim 1 wherein said adjusting tone scale step for transparency prints uses a function which is based on  T  ( D )  D  D = D2 ≤  T  ( D )  D  D = D1 ≥ 0 , where D 1 <D 2 ; and D is density.

Claim 30

Dependent Claim 64 words

The method according to claim 1 wherein said adjusting tone scale step uses a function which is based on d - d min d max - d min = D - D min D max - D min + k  ( D max - D ) , where k≧0 for reflection prints and k≦0 for transparency prints; and d and D are densities.

Claim 31

Dependent Claim 29 words

The method according to claim 1 wherein said sending the processed image step includes linearizing the response of output optical density and input code value of said output device.

Claim 32

Dependent Claim 35 words

The method according to claim 1 wherein said adjusting tone scale step and said sending the processed image step is actually one step in case said output device can provide the required tone scale curve.

Claim 33

Dependent Claim 130 words

A computer storage product comprising: a computer readable storage medium having a computer program for performing a method for the enhancement of medical images for hardcopy prints comprising the steps of: obtaining a medical image in digital format; conducting a plurality of operations for Human Visual System (HVS)-based edge enhancement with each operation having a uniquely specified high frequency amplification function and range such that edges are more enhanced in the shadow region than in the highlight region; adjusting image tone scale, for reflection prints increase the contrast in the shadow region and decrease the contrast in the highlight region, and for transparency prints decrease the contrast in the shadow region and increase the contrast in the highlight region; sending the processed image to the output device for hardcopy prints.

Claim 34

Dependent Claim 130 words

A computer storage product comprising: a computer readable storage medium having a computer program for performing a method for the enhancement of medical images for hardcopy prints comprising the steps of: obtaining a medical image in digital format; conducting a plurality of operations for Human Visual System (HVS)-based edge enhancement with each operation having a uniquely specified high frequency amplification function and range such that edges are more enhanced in the shadow region than in the highlight region; adjusting image tone scale, for reflection prints increase the contrast in the shadow region and decrease the contrast in the highlight region, and for transparency prints decrease the contrast in the shadow region and increase the contrast in the highlight region; sending the processed image to the output device for hardcopy prints.

Claim 35

Dependent Claim 23 words

The method of claim 1 wherein said medical image in digital format is obtained through a network interface from a network input device.

Claim 36

Dependent Claim 20 words

The method of claim 1 wherein said processed image is sent through a network interface to a network output device.

Claim 37

Dependent Claim 23 words

The method of claim 1 wherein said medical image in digital format is obtained through a network interface from a network storage device.

Annuity Stage	Window Opens	Payment Deadline	Surcharge Period Until	Estimated Fee	Status
3.5 Years (Year 4)	2005-07-22	2006-01-21	2006-07-23	$2000.00	Window Closed / Lapsed
7.5 Years (Year 8)	2009-07-22	2010-01-21	2010-07-23	$3760.00	Window Closed / Lapsed
11.5 Years (Year 12)	2013-07-22	2014-01-21	2014-07-23	$7700.00	Window Closed / Lapsed

Medical image enhancement method for hardcopy prints

Abstract

Inventors

Bibliographic Details

Claims Analysis

References Cited (Backward Citations)

USPTO Annuity & Maintenance Windows

Assigned Categories & Tags

Assign Category Tag