摘要:

The geometric accuracy of Landsat Multispectral Scanner (MSS) images both in photographic and digital form was tested by employing different mathematical models. An r.m.s. distortion vector of ± 58 m in the photographic images and of ±65 m in the digital images was obtained. Parametric corrections of distortions caused by along-track variation of the satellite's heading angle were carried out. Without using ground control points, it was possible to reduce the r.m.s. errors in the digital images from ±169 m before correction, to ± 83 m after correction. Working with scenes covering the U.K., with adequate overlapping between adjacent orbits, it was possible to investigate the heighting accuracy of that system. Stereoscopic models were formed by analytical add analogue methods. A modified method of relative orientation was developed to form an analytical model, and the Wild-A8 plotter was employed to measure model coordinates and to examine the plotting possibilities. The r.m.s. ofy-parallax was ±82μmi with the conventional analytical relative orientation method and ±22 μm with the modified method. Different mathematical models were used to fit model coordinates to ground coordinates. Space resection and intersection also were employed to compute ground coordinates from plate coordinates at any adjacent images. An r.m.s. error in height of 69 m was obtained.

ISSN:0143-1161    

DOI:10.1080/01431168108948348

出版商:Taylor & Francis Group    

年代:1981

数据来源: Taylor

摘要:

Spectral hand ratioing in the form of radiance,/radiance, was examined as a proposed means for reducing the topographic effect from muitispectral data. The topographic effect is defined as the variation in radiances from inclined surfaces compared with radiance from a horizontal surface as a function of the orientation of the surfaces relative to the light source and sensor position (Holben and Justice 1980). A ground based nadir pointing two channel radiometer filtered for the red and photographic infrared portions of the electromagnetic spectrum was used to measure the topographic effect from a uniform surface inclined from horizontal to 60°, at 16 compass points, for several solar elevations.

ISSN:0143-1161    

DOI:10.1080/01431168108948349

出版商:Taylor & Francis Group    

年代:1981

数据来源: Taylor

摘要:

A preliminary project was devised to study the forest monitoring potential of side-looking airborne radar. A group often photo interpreters was assembled to evaluate the forest regrowth content of a radar image. A series of 20 cutting locations was selected from U.S. Forest Service data. Categories and category associations were tabulated from each participant's results. Some success was achieved in distinguishing between five major forest categories. Little success was achieved in attempting to subdivide the image content into highly specific categories. It was concluded that the radar has the potential to segregate categories, but interpreters must possess as much radar interpretation expertise as forestry expertise.

ISSN:0143-1161    

DOI:10.1080/01431168108948350

出版商:Taylor & Francis Group    

年代:1981

数据来源: Taylor

摘要:

Landsat multispectral scanner (MSS) data, and U-2 colour and colour infrared photographs were combined within situdata for the assessment of water quality parameters within the San Francisco Bay-Delta. The water quality parameters of interest included turbidity and suspended solids. The U-2 photography and water quality samples were obtained simultaneously and coincidently with Landsat overpass. Regression models were developed between each of the water quality parameter measurements and Landsat digital data for 29 pre-selected sample sites. These regression models were then extended to the entire study area for mapping the water quality parameters of interest. The results included a series of colour-coded maps, each pertaining to one of the water quality parameters, and the statistical summaries. Areas of relatively high biological activity were clearly discernible on digitally enhanced Landsat MSS data.

ISSN:0143-1161    

DOI:10.1080/01431168108948351

出版商:Taylor & Francis Group    

年代:1981

数据来源: Taylor

摘要:

A set of side-looking radar images has been collected over an area in the Sierrita Pediment, Arizona, U.S.A. The dates of image acquisition vary from 1965-1979 and the images are taken at various look angles, frequencies, flight directions and polarizations. The objective of the study is to demonstrate the photogrammetric orthophoto technique applied to radar images and at the same time to study the characteristics of this unique set of radar images taken over the same area by many different sensors. Ten images are presented here, of which five have been rectified using ground control points and a digital height model taken from a map. Errors prior to rectification are shown to amount to several hundred metres on the ground in all cases; after rectification, residual coordinate errors in ground control range from ± 19 m to ±70 m. The contents of the radar images, including one pass from Seasat, were compared with a Landsat image and aerial photography. Observations made confirm a range of conclusions on the effect of system parameters on the radar image. The data set also permitted a unique review of changes that occurred in the area over time, and of variations in radar performance as a function of some system parameters.

ISSN:0143-1161    

DOI:10.1080/01431168108948352

出版商:Taylor & Francis Group    

年代:1981

数据来源: Taylor

摘要:

Two simple photographic methods have recently been proposed for the measurement of relative bidirectional reflectance (Lillesand and Kiefer 1979, Curran 1980). These two methods were used to calculate the relative bidirectional reflectance of ten contrasting surfaces. The photographic relative bidirectional reflectance so recorded, was then compared with the radiometric bidirectional reflectance for each surface. Two conclusions were drawn: first, that relative bidirectional reflectance can be measured using these simple photographic techniques, and second, that there was no significant difference between the Lillesand and Kiefer and Curran methods for photographically deriving relative bidirectional reflectance.

ISSN:0143-1161    

DOI:10.1080/01431168108948353

出版商:Taylor & Francis Group    

年代:1981

数据来源: Taylor

ISSN:0143-1161    

DOI:10.1080/01431168108948354

出版商:Taylor & Francis Group    

年代:1981

数据来源: Taylor

ISSN:0143-1161    

DOI:10.1080/01431168108948355

出版商:Taylor & Francis Group    

年代:1981

数据来源: Taylor

ISSN:0143-1161    

DOI:10.1080/01431168108948356

出版商:Taylor & Francis Group    

年代:1981

数据来源: Taylor