Edward A. Geiser

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In this paper, we report an active contour algorithm that is capable of using prior shapes. The energy functional of the contour is modified so that the energy depends on the image gradient as well as the prior shape. The model provides the segmentation and the transformation that maps the segmented contour to the prior shape. The active contour is able to(More)
This paper presents an algorithm for speckle reduction and contrast enhancement of echocardiographic images. Within a framework of multiscale wavelet analysis, we apply wavelet shrinkage techniques to eliminate noise while preserving the sharpness of salient features. In addition, nonlinear processing of feature energy is carried out to enhance contrast(More)
Digital signal and image processing techniques are acquiring an increasingly important role in the generation and analysis of cardiac images. This is particularly true of 2D echocardiography, in which image acquisition, manipulation, and storage within the echocardiograph, as well as quantitative analysis of echocardiographic data by means of "off-line"(More)
A new variational PDE based level set method for a simultaneous image segmentation and non-rigid registration using prior shape and intensity information is presented. The segmentation is obtained by finding a non-rigid registration to the prior shape. The non-rigid registration consists of both a global rigid transformation and a local non-rigid(More)
In this note we present a coupled optimization model for boundary determination. One part of the model incorporates a prior shape into a geometric active contour model with a fixed parameter. The second part determines the ‘best’ parameter used in the first part by maximizing the mutual information of the image geometry between the prior and an aligned(More)
This study tests the accuracy of a model to calculate left ventricular volume (LVV) and muscle volume (MV) when optimal data were used. These volumes were calculated using endocardial and epicardial borders traced from photos of cross sections of 20 animal (dog, goat and pig) hearts. A pyramid summation algorithm was used to perform a 3-dimensional (3-D)(More)
The load that the arterial system places upon the myocardium during ventricular ejection is of primary importance in the consideration of ventricular function. This dynamic load can be characterized by the total aortic input impedance spectrum obtained from Fourier analysis of pulsatile pressure and flow waves recorded in the ascending aorta. Certain(More)
This paper presents an approach which addresses both de-noising and contrast enhancement. In a multiscale wavelet analysis framework, we take advantage of both soft thresholding and hard thresholding wavelet shrinkage techniques to reduce noise. In addition, we carry out nonlinear processing to enhance contrast within structures and along boundaries.(More)
Introduction: We evaluated a method for autonomous, user-independent automated border delineation (ABD) developed by Geiser and Wilson, by comparing the accuracy of ABD relative to manual border tracing. Methods: Short axis echocardiographic images of 84 patients from 3 clinical sites were analyzed using ABD and by manual tracing performed by two observers(More)
In this paper we propose a new variational framework for image segmentation that incorporates the information of expected shape and a few points on the boundary into geodesic active contours. The energy functional in this model consists of three terms. One measures high image gradients, the other two measure the disparity in shape between the interface and(More)