Biomedical applications of spacecraft image processing techniques, volume 2
Explore the source record for details and available documents.
Source record↗
SEARCH · Search NASA
Results for “imaging techniques”
Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.
Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.
Digital image enhancement techniques used in some ERTS application problems
Enhancements discussed include contrast stretching, multiratio color displays, Fourier plane operations to remove striping and boosting MTF response to enhance high spatial frequency content. The use of each technique in a specific application in the fields of geology, geomorphology and oceanography is demonstrated.
Goetz, A. F. H.↗
A search for sulfide-bearing areas using LANDSAT-1 data and digital image-processing techniques
Two experiments were conducted using LANDSAT-1 multispectral scanner data to identify ground features that are indicators of sulfide-bearing rock. A nearby known sulfide deposit was used as a control. In the first experiment, false-color composites were examined visually to locate possible favorable areas; in the second, favorable areas were classified by digital-computer processing. The results of the experiment show that outcrops of hydrothermally altered and mineralized rock can be identified from LANDSAT-1 data under favorable conditions. The empirical method of digital-computer classification of the multispectral scanner data was relatively unrefined and rapid. The five mineralized prospecting sites identified are in locations that the geologist would not have selected as favorable on the basis of geologic knowledge or photogeologic interpretation at the time of the investigation.
Schmidt, R. G.↗
The integration of manual and automatic image analysis techniques with supporting ground data in a multistage sampling framework for timber resource inventories: Three examples
An approach to information acquisition is discussed in the context of meeting user-specified needs in a cost-effective, timely manner through the use of remote sensing data, ground data, and multistage sampling techniques. The roles of both LANDSAT imagery and Skylab photography are discussed as first stages of three separate multistage timber inventory systems and results are given for each system. Emphasis is placed on accuracy and meeting user needs.
Gialdini, M.↗
Experimental study of digital image processing techniques for LANDSAT data
The author has identified the following significant results. Results are reported for: (1) subscene registration, (2) full scene rectification and registration, (3) resampling techniques, (4) and ground control point (GCP) extraction. Subscenes (354 pixels x 234 lines) were registered to approximately 1/4 pixel accuracy and evaluated by change detection imagery for three cases: (1) bulk data registration, (2) precision correction of a reference subscene using GCP data, and (3) independently precision processed subscenes. Full scene rectification and registration results were evaluated by using a correlation technique to measure registration errors of 0.3 pixel rms thoughout the full scene. Resampling evaluations of nearest neighbor and TRW cubic convolution processed data included change detection imagery and feature classification. Resampled data were also evaluated for an MSS scene containing specular solar reflections.
Rifman, S. S.↗
Image analysis techniques with special reference to analysis and interpretation of geological features from LANDSAT imagery
The principal component analysis enhances the contrast existing between the different cover types present in an imagery. A procedure is presented with regards to the determination of the principal components. The method is tested for a portion of the LANDSAT imagery pertaining to Anantapur region. Another technique, using the concept of non-linear contrast stretching is defined and developed and carried out on the same imagery. The results are presented as photographs. An interpretation of the geology of the region is derived from these photographs.
Kamat, D. S.↗
Feasibility of automated dropsize distributions from holographic data using digital image processing techniques
An automated technique for measuring particle diameters and their spatial coordinates from holographic reconstructions is being developed. Preliminary tests on actual cold-flow holograms of impinging jets indicate that a suitable discriminant algorithm consists of a Fourier-Gaussian noise filter and a contour thresholding technique. This process identifies circular as well as noncircular objects. The desired objects (in this case, circular or possibly ellipsoidal) are then selected automatically from the above set and stored with their parametric representations. From this data, dropsize distributions as a function of spatial coordinates can be generated and combustion effects due to hardware and/or physical variables studied.
Feinstein, S. P.↗
Application of digital image processing techniques to astronomical imagery 1980
Topics include: (1) polar coordinate transformations (M83); (2) multispectral ratios (M82); (3) maximum entropy restoration (M87); (4) automated computation of stellar magnitudes in nebulosity; (5) color and polarization; (6) aliasing.
Lorre, J. J.↗
Radar image interpretation techniques applied to sea ice geophysical problems
The geophysical science problems in the sea ice area which at present concern understanding the ice budget, where ice is formed, how thick it grows and where it melts, and the processes which control the interaction of air-sea and ice at the ice margins is discussed. The science problems relate to basic questions of sea ice: how much is there, thickness, drift rate, production rate, determination of the morphology of the ice margin, storms feeling for the ice, storms and influence at the margin to alter the pack, and ocean response to a storm at the margin. Some of these questions are descriptive and some require complex modeling of interactions between the ice, the ocean, the atmosphere and the radiation fields. All involve measurements of the character of the ice pack, and SAR plays a significant role in the measurements.
Carsey, F. D.↗
Application of computer image enhancement techniques to shuttle hand-held photography
With the advent of frequent Space Transportation System Shuttle missions, photography from hyperaltitudes stands to become an accessible and convenient resource for scientists and environmental managers. As satellite products (such as LANDSAT) continue to spiral in costs, all but the most affluent consumer is finding Earth imagery from space to be more and more unavailable. Therefore, the potential for Shuttle photography to serve a wide variety of users is increasing. However, despite the popularity of photos from space as public relations tools and report illustrations, little work has been performed to prove their scientific worth beyond that as basic mapping bases. It is the hypothesis of this project that hand-held Earth photography from the Space Shuttle has potentially high scientific merit and that primary data can be extracted. In effect, Shuttle photography should be considered a major remote sensing information resource.
David, B. E.↗
Spectral images of HD 199178
High-resolution IUE spectra of the Mg II k line of HD 199178 were analyzed, applying spectral imaging techniques to derive an image of the chromospheric structure and to study the transient behavior of the chromosphere. All spectra in the IUE archives were uniformly reduced and analyzed. Results are compared with ground-based observations of the photosphere. Four ultraviolet flares on HD 199178 are observed; 3 of these occurred at roughly the same rotational phase. There is no clear phase-dependence of the SWP line fluxes, but there is for the Mg II k flux. The emission centroid of the Mg II k line varies in a quasi-sinusoidal fashion, presumably due to the rotation of a nonuniform chromosphere.
Neff, J. E.↗
Microgravity science requirements and the need for data compression
The Microgravity Science and Applications Div. (MSAD) of the NASA Office of Space Science and Applications (OSSA) is responsible for encouraging and directing the research of a wide range of physical phenomena in reduced gravity. Under MSAD's direction, NASA-Lewis is presently developing the concept of a multiuser facility which will perform combustion science experiments in space. This facility, the Combustion Experiment Module (CEM), will be located in either the Shuttle Spacelab or the Space Station Freedom lab and will be operational by mid-1997. In addition to standard instrumentation to measure temperature, pressure, and acceleration, CEM shall use a variety of imaging and optical diagnostic techniques. Images shall be the primary source of experimental data. These images create an enormous amount of data which must be archived on orbit for later analysis. Also, ground based investigators will require enough data from the orbiting facility to determine if the experimental parameters need to be changed before proceeding with the next run. The storage and transmission of this data present a major challenge to the CEM design. Data compression will play a major role in the design of the CEM diagnostics system.
Hartz, William G.↗
Theoretical studies of the outer envelopes of young stellar objects
With the Monte Carlo code developed by Whitney and Hartmann, a series of models was computed of scattering in disks around young stellar objects. The code calculates scattering by dust, including polarization, in arbitrary geometries. By computing model images, it was found that disk, by themselves, around young stellar objects would be very difficult to detect with present day imaging techniques. In comparing these images to observations of young stellar objects which show diffuse structure, little resemblance was found. A flared disk system will only give high polarization when viewed edge-on, and the position angle is always oriented perpendicular to the disk plane. This suggests that an envelope, perhaps the remnant infalling envelope, must be present to scatter more stellar light than a disk can, and obscure the star at many inclinations. A grid was computed of models of scattering in a disk+envelope system. Evidence is presented that the wind of the pre-main sequence object FU Orionis arises from the surface of the luminous prostellar accretion disk. A disk wind model calculated assuming radiative equilibrium explains the differential behavior of the observed asymmetrical absorption line profiles. The model predicts that strong lines should be asymmetric and blueshifted, while weak lines should be symmetric and doubled peaked due to disk rotation, in agreement with observations.
Hartmann, Lee↗
Space Shuttle photographic/television analysis project - An overview of image analysis techniques
The Space Shuttle photographic and television analysis project (SSPTAP) at the Johnson Space Center (JSC) is described. The films and videos of every Space Shuttle launch and landing are scrutinized for information on the vehicle's condition and performance which can only be obtained by photographic means when necessary. On-orbit video is used to assess problems. The photographic information is used with various other data sources to develop feasible scenarios for particular events. The data and methods used to analyze the state of the Shuttle launch vehicle are analyzed, and examples are given of some of the studies that have been conducted.
Dailey, Christine L.↗
VTM--a new method of measuring ocular torsion using image-processing techniques
No abstract available
Non-NASA Center↗
Assessing Hurricane Katrina Vegetation Damage at Stennis Space Center using IKONOS Image Classification Techniques
Hurricane Katrina inflicted widespread damage to vegetation in southwestern coastal Mississippi upon landfall on August 29, 2005. Storm damage to surface vegetation types at the NASA John C. Stennis Space Center (SSC) was mapped and quantified using IKONOS data originally acquired on September 2, 2005, and later obtained via a Department of Defense ClearView contract. NASA SSC management required an assessment of the hurricane s impact to the 125,000-acre buffer zone used to mitigate rocket engine testing noise and vibration impacts and to manage forestry and fire risk. This study employed ERDAS IMAGINE software to apply traditional classification techniques to the IKONOS data. Spectral signatures were collected from multiple ISODATA classifications of subset areas across the entire region and then appended to a master file representative of major targeted cover type conditions. The master file was subsequently used with the IKONOS data and with a maximum likelihood algorithm to produce a supervised classification later refined using GIS-based editing. The final results enabled mapped, quantitative areal estimates of hurricane-induced damage according to general surface cover type. The IKONOS classification accuracy was assessed using higher resolution aerial imagery and field survey data. In-situ data and GIS analysis indicate that the results compare well to FEMA maps of flooding extent. The IKONOS classification also mapped open areas with woody storm debris. The detection of such storm damage categories is potentially useful for government officials responsible for hurricane disaster mitigation.
Spruce, Joseph P.↗
Assessing Hurricane Katrina Vegetation Damage at Stennis Space Center using IKONOS Image Classification Techniques
Hurricane Katrina hit southwestern Mississippi on August 29, 2005, at 9:45 a.m. CDT as a category 3 storm with surges up to approx. 9 m and sustained winds of approx. 120 mph. The hurricane's wind, rain, and flooding devastated several coastal towns, from New Orleans through Mobile. The storm also caused significant damage to infrastructure and vegetation of NASA's SSC (Stennis Space Center). Storm recovery at SSC involved not only repairs of critical infrastructure but also forest damage mitigation (via timber harvests and control burns to reduce fire risk). This presentation discusses an effort to use commercially available high spatial resolution multispectral IKONOS data for vegetation damage assessment, based on data collected over SSC on September 2, 2005.
Spruce, Joseph P.↗
Using Electronic Noses to Detect Tumors During Neurosurgery
It has been proposed to develop special-purpose electronic noses and algorithms for processing the digitized outputs of the electronic noses for determining whether tissue exposed during neurosurgery is cancerous. At present, visual inspection by a surgeon is the only available intraoperative technique for detecting cancerous tissue. Implementation of the proposal would help to satisfy a desire, expressed by some neurosurgeons, for an intraoperative technique for determining whether all of a brain tumor has been removed. The electronic-nose technique could complement multimodal imaging techniques, which have also been proposed as means of detecting cancerous tissue. There are also other potential applications of the electronic-nose technique in general diagnosis of abnormal tissue. In preliminary experiments performed to assess the viability of the proposal, the problem of distinguishing between different types of cultured cells was substituted for the problem of distinguishing between normal and abnormal specimens of the same type of tissue. The figure presents data from one experiment, illustrating differences between patterns that could be used to distinguish between two types of cultured cancer cells. Further development can be expected to include studies directed toward answering questions concerning not only the possibility of distinguishing among various types of normal and abnormal tissue but also distinguishing between tissues of interest and other odorous substances that may be present in medical settings.
Homer, Margie L.↗