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Billingsley, F. C.

Publications and source records attributed to Billingsley, F. C..

At least 55 records · Page 3
All sourcesNASA NTRSDOE OSTI
NASA NTRS1973

Image data rate converter having a drum with a fixed head and a rotatable head

A data-rate converter is disclosed comprising a rotatable data-storing drum with at least one fixed read/record head and a rotatable read/record head. The latter is rotatable in a circular path about the drum axis of rotation. The drum is positionable in any one of a plurality of axial positions with respect to the heads, so that at least one drum track is aligned with the fixed head in one drum position and with the rotatable head in another drum position. When a track is aligned with the fixed head, data may be recorded therin or read out therefrom at a rate which is a function of drum rotation, while when aligned with the rotatable head, data may be recorded or read out at a rate which is a function of the rates and directions of rotation of both the drum and the head.

Billingsley, F. C.↗
NASA NTRS1973

Machine processing methods for earth observational data

A brief review of the development over the last decade of earth resource information systems is presented. Machine data preprocessing and analysis methods are surveyed and illustrated. These include preprocessing steps intended to modify geometric and radiometric aspects of earth observational image data to enhance the ability of either human interpreters or machine algorithms to extract information from the data. Illustrations of processed and analyzed images from spaceborne sensors including the Earth Resources Technology Satellite are discussed.

Landgrebe, D. A.↗
NASA NTRS1973

Application of ERTS and EREP images to geologic investigations of the basin and range: Colorado Plateau boundary in northwestern and north central Arizona

The author has identified the following significant results. Regional mapping using ERTS-1 images has led to the recognition of two parallel northeast-trending systems of normal faults, the Bright Angel and Mesa Butte fault systems, each of which can be traced at least 100 miles. Many eruptive centers appear to be localized along these fault systems or along their extensions. The faults are chiefly observed in Phanerozoic rocks and have minor displacement, but are interpreted to reflect fault zones of major displacement in the crystalline Precambrian basement. The location of epicenters of recent earthquakes and reports of earthquakes by residents in the region suggest that the Bright Angel and Mesa Butte fault systems are currently active.

Goetz, A. F. H.↗
NASA NTRS1973

Image data rate converter: A concept

Establish data tracks on periphery of rotating drum and axially displace entire drum to place given track in alignment with either fixed or rotating read/record head. Accurate control of speed drum and rotating head can be accomplished by using separate synchronous motors driven by digitally-set oscillators to provide required difference in speed.

Billingsley, F. C.↗
NASA NTRS1973

Digital image processing for information extraction.

The modern digital computer has made practical image processing techniques for handling nonlinear operations in both the geometrical and the intensity domains, various types of nonuniform noise cleanup, and the numerical analysis of pictures. An initial requirement is that a number of anomalies caused by the camera (e.g., geometric distortion, MTF roll-off, vignetting, and nonuniform intensity response) must be taken into account or removed to avoid their interference with the information extraction process. Examples illustrating these operations are discussed along with computer techniques used to emphasize details, perform analyses, classify materials by multivariate analysis, detect temporal differences, and aid in human interpretation of photos.

Billingsley, F. C.↗
NASA NTRS1973

Preliminary geologic investigations in the Colorado Plateau using enhanced ERTS images

Bulk and computer enhanced frames of the Verde Valley region of Central Arizona, have been analyzed for structural information and rock unit identification. Most major rock units in areas of sparse ground cover are identifiable on enhanced false-color composites. Regional structural patterns are strikingly visible on the ERTS images. New features have been identified which will aid in the search for ground water near Flagstaff, Sedona and Stewart Ranch.

Goetz, A. F. H.↗
NASA NTRS1973

Computer techniques used for some enhancements of ERTS images

The JPL VICAR image processing system has been used for the enhancement of images received from the ERTS for the Arizona geology mapping experiment. This system contains flexible capabilities for reading and repairing MSS digital tape images, for geometric corrections and interpicture registration, for various enhancements and analyses of the data, and for display of the images in black and white and color.

Billingsley, F. C.↗
NASA NTRS1973

Some digital techniques for enhancing ERTS imagery

In addition to the use of simple contrast stretching to improve visibility of detail, axis rotation and ratioing have been found useful for certain applications. These processes allow a considerably greater contrast stretch than is possible on normal images, with consequent increased separability of different materials. They have inherent advantages over classifier techniques for geologic studies, as they allow the interpreter to take into account other factors such as context and structure before interpreting boundaries between units. Color images reconstructed from these pictures display color variations among various materials unattainable by any combination of normal photography.

Billingsley, F. C.↗
NASA NTRS1972

Digital image processing for photo-reconnaissance applications

Digital image-processing techniques developed for processing pictures from NASA space vehicles are analyzed in terms of enhancement, quantitative restoration, and information extraction. Digital filtering, and the action of a high frequency filter in the real and Fourier domain are discussed along with color and brightness.

Billingsley, F. C.↗
NASA NTRS1972

Photo-reconnaissance applications of computer processing of images.

Discussion of imaging processing techniques for enhancement and calibration of Jet Propulsion Laboratory imaging experiment pictures returned from NASA space vehicles such as Ranger, Mariner and Surveyor. Particular attention is given to data transmission, resolution vs recognition, and color aspects of digital data processing. The effectiveness of these techniques in applications to images from a wide variety of sources is noted. It is anticipated that the use of computer processing for enhancement of imagery will increase with the improvement and cost reduction of these techniques in the future.

Billingsley, F. C.↗