Showing papers on "Histogram equalization published in 1986"

Color equalization method and its application to color image processing

Abstract: A method of digital color-image processing is described that leads to the equalization of the brightness histogram and of conditional saturation histograms for each hue area. Means for solving problems that arise in the practical realization of the method are considered. Color equalization can be directly used for preparation of color images for interpretation and for the enhancement of color pictures for visual quality. In the first case, application of the method can result in an increase of the visibility of objects that are initially almost indistinguishable. In the second case it leads to multicolored pictures with unchanged color features.

Method for eliminating noise in regions of a color image exhibiting a specific color

Abstract: A spatial image processing method for noise elimination, including the steps of subjecting an image signal representing a color image and including a density data signal component and a color data signal component to processing for extracting color data for each picture element of the image, discriminating regions of the color image exhibiting a specific color on the basis of the extracted color data, and subjecting the image signal to spatial image processing for elimination of noise under different processing conditions for regions of the image exhibiting the specific color and the remaining regions of the image not exhibiting the specific color.

Image Processing For Automatic Alignment In The Nova Laser Facility

Abstract: The Nova laser is a high-power, pulsed, neodymium-glass system used for inertial confinement fusion and X-ray laser research at the Lawrence Livermore National Laboratory. The control system aligns the ten 250-m-long beams by closing approximately 300 automatic loops. TV alignment sensor images are image processed to extract laser beam and reference information. Two-dimensional techniques that have been applied to process these images include correlation, convolution, gradient, centroid, Hough transform, and histogram equalization. These techniques combine to form algorithms that are relatively insensitive to image Intensity. This paper describes practical image processing methods and reliability measures developed for automatic alignment.

Image processing device

Abstract: PURPOSE:To display a picture whose brightness is properly converted without needing an external computer and to improve the workability by providing a luminance conversion table memory, a histogram memory, and plural selectors. CONSTITUTION:An input data is supplied to the address in the luminance conversion table memory 1 through the selector 12, and after the conversion by the table, inputted to an output selector 13. This data is selected by the selector 22 at the time of histogram measuring. The selector 21 selects the data-input of the histogram memory 2, but selects the output of an adder 24 at the time of histogram measuring. Also, the selector 23 supplies an addition-data to an adder 24, and selects '0' or '1' at the time of histogram measuring. The histogram equalization for the input data is completed by the above components joined by the selector 11, a register 25, a counter 26, and a control part 27. By the selector 13 selecting the memory 1, a picture whose brightness is properly converted can be displayed and the workability is improved.

Digital Image Enhancement Techniques For Nondestructive Evaluation

Abstract: Computer image enhancement of digitized radiographic and conventional photographs have taken advantage of several unique state-of-the-art developments to reveal anomalies in aerospace hardware. Signal processing of such imagery at TASC includes multi-frame averaging to increase signal-to-noise levels, applying specially-developed filters to sharpen details without sacrificing image information, and performing local contrast stretch and histogram equalization to display structure in low-contrast areas. Edge detection, normally complicated in radiographic images by low-contrast, poor spatial resolution, and noise, is performed as a post-processing operation and utilizes a difference-of-Gaussians method and a least-squares fitting procedure. With these software tools, multi-image signal processing allows for the precise measurement (to within + 0.02 inches, rms) of structural motion within a rocket motor during a static test firing as well as identifying stress conditions in turbine blades and matrix anomalies in composite materials. These and other image enhancement examples of aerospace hardware analysis are detailed in the presentation.

One approach to color image processing

Abstract: A basic concept is shown of color image processings without destroying the color balance. Applications to the emphasis of endoscopic images and to a color image restoration are presented.

Some Aspects of Mr Image Processing and Display: Simulation Studies, Multiresolution Segmentation, and Adaptive Histogram Equalization

Abstract: In the years 1982–1984 we have designed and built a software system for the quantitative processing, analysis and display of magnetic resonance 2D and 3D images and timeseries of images This system supports two research projects in our university, “NMR in Oncology”, and “MRI Processing and Simulation Studies”