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At least 469 records · Page 26
All sourcesNASA NTRSDOE OSTI
NASA NTRS1983

Evaluation of LANDSAT-4 TM and MSS ground geometry performance without ground control

Techniques and software developed to characterize the Washington, D.C. scene were improved and are being systematically applied to an Imperial Valley, CA scene. Digital elevation files are being acquired. One hundred seventy-two tiepoints were located in the Imperial Valley scene. They were digitized from USGS maps to determine their lat-long coordinates. A least squares fit is currently being performed between line-sample image data and the lat-long positions of the tiepoints. Thematic mapper scanner sweeps were determined for the Imperial Valley P-data. VICAR jobs are currently under way to analyze sample-direction offsets between sweeps in the data, as well as band to band registration offsets. Tiepoint location is about to begin in the Harrisburg, PA scene.

Bryant, N. A.↗
NASA NTRS1983

Impact of LANDSAT MSS sensor differences on change detection analysis

Some 512 by 512 pixel subwindows for simultaneously acquired scene pairs obtained by LANDSAT 2,3 and 4 multispectral band scanners were coregistered using LANDSAT 4 scenes as the base to which the other images were registered. Scattergrams between the coregistered scenes (a form of contingency analysis) were used to radiometrically compare data from the various sensors. Mode values were derived and used to visually fit a linear regression. Root mean square errors of the registration varied between .1 and 1.5 pixels. There appear to be no major problem preventing the use of LANDSAT 4 MSS with previous MSS sensors for change detection, provided the noise interference can be removed or minimized. Data normalizations for change detection should be based on the data rather than solely on calibration information. This allows simultaneous normalization of the atmosphere as well as the radiometry.

Likens, W. C.↗
NASA NTRS1983

Shear zone ice deformation using supervised analysis of Seasat data

Spacecraft and aircraft Synthetic-Aperture Radar (SAR) images are commonly used to compute sea ice conditions including especially the drift velocities of ice features. Recent developments, described in this paper, in computer-aided analysis and in digital image processing have extended the analysis speed and accuracy of registration to the point that ice deformation can be examined on the geophysically important scales of about 100 m over tens of kilometers between two 'snapshots.' Examples are shown for the ice motion and rotation in the shear zone near the Alaska coast from Seasat data in 1978.

Carsey, F.↗
NASA NTRS1983

Comparison of winter-nocturnal geostationary satellite infrared-surface temperature with shelter-height temperature in Florida

Geostationary satellite surface temperatures derived from a Visible and Infrared Spin Scan Radiometer (VISSR) sensor (10.5 to 12.6 microns) were compared with 1.5-m air temperatures collected by a thermocouple on a traversing vehicle along rural highway transects in Florida, and with two fixed thermographs located in rural and agricultural areas. Statistical comparisons between satellite and 1.5-m observations yielded a mean correlation coefficient of 0.87 and an average sample standard deviation from regression of 1.57 C during clear nights for four winters (1978-1981). The satellite-temperature image of Lake Okeechobee was compared with its geographic outline for areal image registration. Manual overlays of temporal images were repeatable to within one pixel. Satellite-sensed water temperature of Lake Okeechobee was used as an indicator of satellite radiometer repeatability and stability.

Chen, E.↗
NASA NTRS1985

Relational Information Management Data-Base System

DBMS with several features particularly useful to scientists and engineers. RIM5 interfaced with any application program written in language capable of Calling FORTRAN routines. Applications include data management for Space Shuttle Columbia tiles, aircraft flight tests, high-pressure piping, atmospheric chemistry, census, university registration, CAD/CAM Geometry, and civil-engineering dam construction.

Storaasli, O. O.↗
NASA NTRS1983

LANDSAT-D investigations in snow hydrology

Progress on the registration of TM data to digital topographic data; on comparison of TM, MSS and NOAA meteorological satellite data for snowcover mapping; and on radiative transfer models for atmospheric correction is reported. Some methods for analyzing spatial contiguity of snow within the snow covered area were selected. The methods are based on a two-channel version of the grey level co-occurence matrix, combined with edge detection derived from an algorithm for computing slopes and exposures from digital terrain data.

Dozier, J.↗
NASA NTRS1983

LANDSAT-4 sensor performance

Preflight and in-orbit sensor and data measurements indicate that TM meets or exceeds most specifications. Measured spectral band edges meet instrument specifications in 12 out of 14 cases; there is ample dynamic range. The signal-to-noise ratio exceeds specifications, except for band 3, channel 4; and band 7 channel 7 is very noisy but still meets specifications. The modulation transfer function of channel 4, band 2, is smaller than specified. Registration errors between the primary focal plane (PFP) and the cold focal plane (CFP) are about 0.75 pixels along-scan and 0.2 pixels across scan. Forward and reverse scan discontinuities, are well within ground-processing capabilities to rectify. Instrument gain variability, up to 7% for band 5, requires use of the internal calibration (IC) system to assure radiometric accuracy. Preliminary applications evaluation of image contents indicates that TM provides much better definition of edges than MSS.

Barker, J. L.↗
NASA NTRS1983

Crop identification of SAR data using digital textural analysis

After preprocessing SEASAT SAR data which included slant to ground range transformation, registration to LANDSAT MSS data and appropriate filtering of the raw SAR data to minimize coherent speckle, textural features were developed based upon the spatial gray level dependence method (SGLDM) to compute entropy and inertia as textural measures. It is indicated that the consideration of texture features are very important in SAR data analysis. The SEASAT SAR data are useful for the improvement of field boundary definitions and for an earlier season estimate of corn and soybean area location than is supported by LANDSAT alone.

Nuesch, D. R.↗
NASA NTRS1983

Performance evaluation of the JPL interim digital SAR processor

The performance of the Interim Digital SAR Processor (IDP) was evaluated. The IDP processor was originally developed for experimental processing of digital SEASAT SAR data. One phase of the system upgrade which features parallel processing in three peripheral array processors, automated estimation for Doppler parameters, and unsupervised image pixel location determination and registration was executed. The method to compensate for the target range curvature effect was improved. A four point interpolation scheme is implemented to replace the nearest neighbor scheme used in the original IDP. The processor still maintains its fast throughput speed. The current performance and capability of the processing modes now available on the IDP system are updated.

Wu, C.↗
NASA NTRS1983

Investigation of several aspects of LANDSAT-4 data quality

Preliminary analysis of band-to-band registration in a TM scene of San Francisco, California by flickering different band pairs on the display showed no major problems. The power spectra of individual lines in each band on the A-tape of a Washington, D.C. scene, which represented data from individual detectors, was calculated. The power spectra for each detector were averaged and the peak-to-peak amplitudes were calculated as a function of frequency. Estimated system modulation transfer functions were calculated for bands 3 and 4 for a 128 x 128 pixel area of the San Francisco Bay containing the San Matteo Bridge. The shape and width of the modulation transfer functions appear reasonable, but further study is required to establish confidence in the results which yield an effective-instantaneous field of view of 33.6 meters and 40.8 meters in bands 3 and 4, respectively.

Wrigley, R. C.↗
NASA NTRS1983

Performance appraisal of VAS radiometry for GOES-4, -5 and -6

The first three VISSR Atmospheric Sounders (VAS) were launched on GOES-4, -5, and -6 in 1980, 1981 and 1983. Postlaunch radiometric performance is assessed for noise, biases, registration and reliability, with special attention to calibration and problems in the data processing chain. The postlaunch performance of the VAS radiometer meets its prelaunch design specifications, particularly those related to image formation and noise reduction. The best instrument is carried on GOES-5, currently operational as GOES-EAST. Single sample noise is lower than expected, especially for the small longwave and large shortwave detectors. Detector to detector offsets are correctable to within the resolution limits of the instrument. Truncation, zero point and droop errors are insignificant. Absolute calibration errors, estimated from HIRS and from radiation transfer calculations, indicate moderate, but stable biases. Relative calibration errors from scanline to scanline are noticeable, but meet sounding requirements for temporarily and spatially averaged sounding fields of view. The VAS instrument is a potentially useful radiometer for mesoscale sounding operations. Image quality is very good. Soundings derived from quality controlled data meet prelaunch requirements when calculated with noise and bias resistant algorithms.

Chesters, D.↗
NASA NTRS1984

CCRS proposal for evaluating LANDSAT-4 MSS and TM data

The measurement of registration errors in LANDSAT MSS data is discussed as well as the development of a revised algorithm for the radiometric calibration of TM data and the production of a geocoded TM image.

Strome, W. M.↗
NASA NTRS1984

Performance evaluation and geologic utility of LANDSAT-4 TM and MSS data

Radiometric calibration accuracy of TM data, radiometric comparison of A-, B-, and P-format data, and geometric registration accuracy of the TM data at enlarged scales were analyzed. Radiometric analysis of the Wind River Basin, Wyoming scene demonstrates that the TM system can be used to extract image reflectance spectra from ground targets following calibration of the system. It was also demonstrated that: (1) image DN (radiance values) vs. ground reflectance calibration scatterplots yield parameters which can be used to constrain atmospheric models and can determine TM radiometric sensitivity; (2) no significant degradation occurs as a result of radiometric and geometric correction by SCROUNGE processing; and (3) TM data can be enlarged to 1:24000 with no major geometric distortions or misregistration problems to USGS topographic maps.

Paylor, E. D.↗
NASA NTRS1983

Remote sensing of agricultural crops and soils

Research in the correlative and noncorrelative approaches to image registration and the spectral estimation of corn canopy phytomass and water content is reported. Scene radiation research results discussed include: corn and soybean LANDSAT MSS classification performance as a function of scene characteristics; estimating crop development stages from MSS data; the interception of photosynthetically active radiation in corn and soybean canopies; costs of measuring leaf area index of corn; LANDSAT spectral inputs to crop models including the use of the greenness index to assess crop stress and the evaluation of MSS data for estimating corn and soybean development stages; field research experiment design data acquisition and preprocessing; and Sun-view angles studies of corn and soybean canopies in support of vegetation canopy reflection modeling.

Bauer, M. E.↗
NASA NTRS1984

Application of LANDSAT data to the study of urban development in Brasilia

The urban growth of Brasilia within the last ten years is analyzed with special emphasis on the utilization of remote sensing orbital data and automatic image processing. The urban spatial structure and the monitoring of its temporal changes were examined in a whole and dynamic way by the utilization of MSS-LANDSAT images for June (1973, 1978 and 1983). In order to aid data interpretation, a registration algorithm implemented in the Interactive Multispectral Image Analysis System (IMAGE-100) was utilized aiming at the overlap of multitemporal images. The utilization of suitable digital filters, combined with the images overlap, allowed a rapid identification of areas of possible urban growth and oriented the field work. The results obtained in this work permitted an evaluation of the urban growth of Brasilia, taking as reference the proposal stated for the construction of the city in the Pilot Plan elaborated by Lucio Costa.

Parada, N. D. J.↗
NASA NTRS1984

Evaluating LANDSAT-4 MSS and TM data

Interband line pixel misregistrations were determined for the four MSS bands of the Mistassini, Ontario scene and multitemporal registration of LANDSAT-4 products were tested for two different geocoded scenes. Line and pixel misregistrations are tabulated as determined by the manual ground control points and the digital band to band correlation techniques. A method was developed for determining the spectral information content of TM images for forestry applications.

Strome, W. M.↗
NASA NTRS1984

Thematic Mapper Sensor Characteristics

The characteristics of the thematic mapper (TM) sensor onboard the LANDSAT 4 satellite are discussed. Topics include instantaneous field of view size, rise time, delay time, square wave response, bright target recovery, altitude effects, band to band registration, and scan profile linearity.

Engel, J.↗