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Dye, R. H.

Publications and source records attributed to Dye, R. H..

A quantitative assessment of resampling errors

Applications associated with digital geographic imagery are subject to great diversity in required cell size, cartographic projection, etc. The need for resampling remote sensing scaner data is evident in all but the most undemanding cases. It is shown that proper resampling of such data is dependent in important ways on the detailed knowledge of the original scanner's effective point-spread function and to the desired point-spread function of resampled data. When both of these are known, it is relatively straightforward to compute the resampling coefficients which do the best job of approximating the shape and position of the synthesized point-spread function. The resulting synthesized psf are compared with an ideal psf located at various interpixel positions and any differences observed as errors.

Dye, R. H.

The Remote Analysis Station (RAS) as an instructional system

"Hands-on" training in LANDSAT data analysis techniques can be obtained using a desk-top, interactive remote analysis station (RAS) which consists of a color CRT imagery display, with alphanumeric overwrite and keyboard, as well as a cursor controller and modem. This portable station can communicate via modem and dial-up telephone with a host computer at 1200 baud or it can be hardwired to a host computer at 9600 baud. A Z80 microcomputer controls the display refresh memory and remote station processing. LANDSAT data is displayed as three-band false-color imagery, one-band color-sliced imagery, or color-coded processed imagery. Although the display memory routinely operates at 256 x 256 picture elements, a display resolution of 128 x 128 can be selected to fill the display faster. In the false color mode the computer packs the data into one 8-bit character. When the host is not sending pictorial information the characters sent are in ordinary ASCII code. System capabilities are described.

Rogers, R. H.

Analog table look-up device identifies unknown terrain

Table provides a probability map defining unknown terrain in terms of known terrain inputs. Device consists of analog transformation network and flying spot scanner. Information is useful to manufacturers and users of remote sensing equipment and applies to automated quality control.

Dye, R. H.