Abstract: A method is disclosed for resolving misregistration errors resulting from dual energy double-shot projection radiographic image acquisition. The method involves an iterative multi-scale, multi-resolution registration process that corrects misregistration errors progressively at scales ranging from bulk anatomical drift down to smaller scale motion such as that of fine pulmonary vasculature. The method may be incorporated as part of a dual energy image processing chain to create dual energy images with improved image quality and diagnostic performance.

Abstract: Methods are provided for cardiac gating of multiple-energy projection radiographic imaging utilizing an apparatus that measures the patient's peripheral blood perfusion. The choice of methods is dependant on the patient's heart rate and the delays inherent in the imaging system. A first method allows for imaging during the diastole period of the current cardiac cycle. A second method provides an implemented delay to acquire the image during the diastole period of a subsequent cardiac cycle. The use of the apparatus that measures the patient's peripheral blood perfusion allows for an efficient and convenient means of cardiac gating while avoiding occlusion of diagnostically important anatomy.

Abstract: A method is disclosed for resolving misregistration errors resulting from dual energy double-shot projection radiographic image acquisition. The method involves an iterative multi-scale, multi-resolution registration process that corrects misregistration errors progressively at scales ranging from bulk anatomical drift down to smaller scale motion such as that of fine pulmonary vasculature. The method may be incorporated as part of a dual energy image processing chain to create dual energy images with improved image quality and diagnostic performance.

Abstract: Methods are provided for cardiac gating of multiple-energy projection radiographic imaging utilizing an apparatus that measures the patient's peripheral blood perfusion. The choice of methods is dependant on the patient's heart rate and the delays inherent in the imaging system. A first method allows for imaging during the diastole period of the current cardiac cycle. A second method provides an implemented delay to acquire the image during the diastole period of a subsequent cardiac cycle. The use of the apparatus that measures the patient's peripheral blood perfusion allows for an efficient and convenient means of cardiac gating while avoiding occlusion of diagnostically important anatomy.

Abstract: A method for displaying components of a multi-component image in which a smaller selected region of one image component of a multi-component image is superimposed upon a larger section of another image component of the same multi-component image. The method includes: providing a multi-component digital image having at least first and second image components; displaying the first image component of the digital image; selecting a region of interest from the first image component; selecting the second image-component that is to be viewed in the region of interest of the first image component; and replacing the first image component with the second image component in the selected region of interest.

Abstract: 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.

Abstract: A phantom for use in measuring parameters in a digital radiography image system comprising a substantially rectangular member of an x-ray attenuating material; a first rectangular array of landmarks associated with the member for use in geometry measurements; a set of regions associated with the central position of the member for exposure linearity and accuracy measurement and a set of sharp angular edges part of one of the regions for modulation transfer function measurements.

Abstract: A method of analyzing the low- and high-frequency components of a digital image comprising the steps of: providing a rectangular digital image; specifying the size of a rectangular kernel; partitioning the image into nine sub-regions; processing each of said sub-regions using a unique image processing algorithm; combining said processed sub-regions into a resulting image of the low frequency component and of the original image subtracting the low frequency component from the original image to obtain the high frequency component of said original image.

Abstract: A method of selecting a tone scale adjustment function for displaying a medical image on a display comprising the steps of: providing a medical image object having a header with image attributes including at least modality value and manufacturer value; extracting the image attribute values from the header of the medical image object; providing a plurality of tone scale adjustment look up tables, each of which is uniquely identified by at least two image attributes; selecting a tone scale adjustment table from a tone scale selection criteria table; applying the selected tone scale adjustment table to the provided medical image; and displaying the tone scale adjusted medical image.

Abstract: A method for compressing the dynamic range of a digital radiographic image comprising the steps of: providing an original digital radiographic image; processing the original digital radiographic image with an unsharp masking technique to produce a low frequency digital radiographic image having low frequency components; subtracting the low frequency digital radiographic image from the original digital radiographic image to produce a high frequency digital radiographic image; multiplying the low frequency image by a first gain factor and the high frequency image by a second gain factor to produce respective modified low and high frequency images; combining the modified low and high frequency images with a mid-range image to produce an output digital image; and passing the output digital image through a look-up table to render an image with code values that represent optical density of a printed or displayed rendering of the image.

Abstract: A method for enhancing a digital image comprises the following steps.1. Providing a digital image.2. Decomposing the image into a multiresolution representation having low frequency images and high frequency images.3. Performing dynamic range modification on the low frequency images.4. Modifying the high frequency images with a method incorporating noise estimation, anatomical regions of importance, and edge estimation, such modification being a combination of attenuation and amplification.5. Combining the processed resolution images to form a resulting image.6. Shifting the pixel values of the resulting image to map the values into a desired range.7. Applying a tonescale to the shifted image for display.

Abstract: A method is disclosed for constructing a tone scale curve. In this curve, equal log exposure differences in an x-ray image of an object produce substantially equal brightness differences in a displayed image.