Band Registration Research Articles

유리함수모델 기반 표고시차보상기법을 사용한 Image Registration 방안 제안

위성 카메라의 두 밴드가 다른 관측 각(Look angle)으로 촬영 시, 두 밴드간의 정합이 요구된다. 밴드 정합(Band registration)은 플랫폼의 다이나믹스(Dynamics)와 시차효과로 인하여 상수매개변수(constant parameter)로 수학적인 모델을 수립하여 정합(registration)을 수행하기 어렵다. 시차효과는 지표면 표고에 의해 야기되는 현상으로 이는 두 밴드간 정합 특성이 지표면의 표고의 함수로 주어진다. 두 밴드간 정합이 성공적으로 이뤄지기 위하여 시차효과를 보상하는 표고시차보상기법이 요구된다. 이러한 표고시차보상은 특히 고해상도 영상정합에서 중요하다. 표고시차보상기법은 하나의 밴드를 다른 관측 각을 가지는 다수의 CCD라인으로 구성한 경우에도 적용이 가능하다. 한 밴드에서 촬영된CCD라인 영상들은 연결된CCD라인마다 다른 관측 각을 가짐으로CCD라인간 표고시차가 발생하여 CCD라인간 지상거리 차가 표고에 따라 증가되는 왜곡 현상이 나타나기 때문이다. 이를 보상하기 위해 기준밴드 또는 기준 CCD라인과 대상밴드 또는 대상 CCD라인간 영상과 지상간의 관계를 다항식을 사용하여 수학적으로 모델 하는RFM을 사용하였다. 실험결과, 표고시차가 존재하는 영상에 대해서도 제안된 기법으로 밴드 정합이 성공적으로 수행되는 것을 확인하였다. When two bands have different look angle in a space-borne camera system, the registration between two bands is required. The registration cannot be modeled with constant parameters because of dynamic of platform and parallax effect. The parallax effect is caused by terrain relief, hence it causes local distortion between two bands. Therefore, the terrain relief correction in order to reduce the parallax effect is required for better registration result, especially for high resolution image data. Such terrain relief correction also can be applied to image data acquired from multiple detectors with different look angle within a band, which is a one of commonly used configuration for a wider swath in space-borne camera system, in order to reduce the distortion between detectors. The RFM is a popular abstract model in remote sensing field, which gives us the relationship between the image plane and geodetic coordinate system. Therefore, we propose a terrain relief correction method based on the RFM. The experiment showed very promising result.

AN EXPERIMENTAL ANALYSIS OF BAND TO BAND REGISTRATION ERROR IN HIGH RESOLUTION SATELLITE REMOTE SENSING IMAGERY

Being one of the important factors responsible for image quality,the band to band registration error of high resolution imagery affects considerably the application precision of remote sensing.The guideline of band to band registration error is an important parameter for developing the remote sensing satellite.In the experimental studies,the authors analyzed the influence of band to band registration error on remote sensing application in such aspects as geometry registration,vision effect,image interpretation,unsupervised classification,and data fusion.The guideline of band to band registration error of high resolution imagery is summarized in this paper.

Space-based observations of O 2 A (0,0) band emission near the solar terminator and their interpretation

The LSO (Lightning and Sprite Observations) experiment under sunset/sunrise conditions from International Space Station (ISS) has provided new information about the emission of the visible and near infrared portions of the optical spectrum. Two CCD cameras have been used in the LSO experiment. One of them had a filter for the Atmospheric O 2 (0–0) band registration (762 ± 5 nm). Observations have been performed at limb- and nadir-viewing geometry. Images obtained by both cameras under sunset/sunrise conditions demonstrate the sharp emission layer at an altitude about 90 km. The images have been obtained when tropospheric, stratospheric and lower mesospheric domains were in the Earth’s shadow, and the upper atmosphere regions were illuminated by the rising or setting Sun. The O 2 A (0,0) band emission layer at 90 km was simulated with known chemistry. The major production process of the airglow is O( 1D) production by ozone photolysis followed by energy transfer from O( 1D) to O 2, generating the metastable excited state, O 2 ( b 1 Σ g + ) . It has been shown that under sunset/sunrise conditions the “secondary ozone maximum” provides the main contribution to the observed O 2 A (0,0) band emission. The images taken with these cameras clearly show a vertical distribution of airglow and demonstrate its appreciable variations with horizontal distance across the cameras field of view. The latter feature may be used as a tool for global monitoring of gravity wave activity at the upper mesosphere/lower thermosphere region.

Narrow band deformable registration of prostate magnetic resonance imaging, magnetic resonance spectroscopic imaging, and computed tomography studies

Endorectal (ER) coil-based magnetic resonance imaging (MRI) and magnetic resonance spectroscopic imaging (MRSI) is often used to obtain anatomic and metabolic images of the prostate and to accurately identify and assess the intraprostatic lesions. Recent advancements in high-field (3 Tesla or above) MR techniques affords significantly enhanced signal-to-noise ratio and makes it possible to obtain high-quality MRI data. In reality, the use of rigid or inflatable endorectal probes deforms the shape of the prostate gland, and the images so obtained are not directly usable in radiation therapy planning. The purpose of this work is to apply a narrow band deformable registration model to faithfully map the acquired information from the ER-based MRI/MRSI onto treatment planning computed tomography (CT) images. A narrow band registration, which is a hybrid method combining the advantages of pixel-based and distance-based registration techniques, was used to directly register ER-based MRI/MRSI with CT. The normalized correlation between the two input images for registration was used as the metric, and the calculation was restricted to those points contained in the narrow bands around the user-delineated structures. The narrow band method is inherently efficient because of the use of a priori information of the meaningful contour data. The registration was performed in two steps. First, the two input images were grossly aligned using a rigid registration. The detailed mapping was then modeled by free form deformations based on B-spline. The limited memory Broyden-Fletcher-Goldfarb-Shanno algorithm (L-BFGS), which is known for its superior performance in dealing with high-dimensionality problems, was implemented to optimize the metric function. The convergence behavior of the algorithm was studied by self-registering an MR image with 100 randomly initiated relative positions. To evaluate the performance of the algorithm, an MR image was intentionally distorted, and an attempt was then made to register the distorted image with the original one. The ability of the algorithm to recover the original image was assessed using a checkerboard graph. The mapping of ER-based MRI onto treatment planning CT images was carried out for two clinical cases, and the performance of the registration was evaluated. A narrow band deformable image registration algorithm has been implemented for direct registration of ER-based prostate MRI/MRSI and CT studies. The convergence of the algorithm was confirmed by starting the registration experiment from more than 100 different initial conditions. It was shown that the technique can restore an MR image from intentionally introduced deformations with an accuracy of approximately 2 mm. Application of the technique to two clinical prostate MRI/CT registrations indicated that it is capable of producing clinically sensible mapping. The whole registration procedure for a complete three-dimensional study (containing 256 x 256 x 64 voxels) took less than 15 min on a standard personal computer, and the convergence was usually achieved in fewer than 100 iterations. A deformable image registration procedure suitable for mapping ER-based MRI data onto planning CT images was presented. Both hypothetical tests and patient studies have indicated that the registration is reliable and provides a valuable tool to integrate the ER-based MRI/MRSI information to guide prostate radiation therapy treatment.

A geometric performance assessment of the EO-1 advanced land imager

The Earth Observing 1 (EO-1) Advanced Land Imager (ALI) demonstrates technology applicable to a successor system to the Landsat Thematic Mapper series. A study of the geometric performance characteristics of the ALI was conducted under the auspices of the EO-1 Science Validation Team. This study evaluated ALI performance with respect to absolute pointing knowledge, focal plane sensor chip assembly alignment, and band-to-band registration for purposes of comparing this new technology to the heritage Landsat systems. On-orbit geometric calibration procedures were developed that allowed the generation of ALI geometrically corrected products that compare favorably with their Landsat 7 counterparts with respect to absolute geodetic accuracy, internal image geometry, and band registration.

Geometric processing of hyperspectral image data acquired by VIFIS on board light aircraft

The Variable-Interference-Filter Imaging Spectrometer (VIFIS) is an airborne imaging system. Unlike usual airborne spectrometers, the image acquisition of VIFIS is based on 2D sensors with its pixel spatially registered to different passing wavelengths. The correction of perturbations upon the VIFIS platform, required by the hyperspectral image generation, relies solely on the information extracted from the 2D pushbroom image flow. In this paper, we present an analysis of the distortions of the pushbroom scan caused by perturbations upon the platform. Hyperspectral image generation algorithms and band registration methods are also discussed. A practical pre-processing approach is developed to automatically track the displacements and generate up to 64 hyperspectral bands. Finally, a pre-processing example is presented as a demonstration of the overall methodology.

Abundance and Distribution of Amphibians in Aukštaitija National Park

In 1997, investigations of amphibian species composition, their abundance, distribution in different biotopes were investigated as well as sex ratio was determined, and the abundance of some juveniles after metamorphosis were established. Band registration (with the standard length of 1 km) or “coil-pipe” route methods have been applied for the investigations (Shliakchtin, Golikova, 1986). Ten species of amphibians have been found in Aukstaitija National Park. Within the area of the most common ten biotopes of Aukstaitija NP, three non-caudate amphibian species predominate and are widespread. Common (grass) frog (R. temporaria) is the most common. Its density in the meadows reaches 14.01-57.0 ind/0.1 ha of the territory. Moor frog (R. arvalis) is the most common – 2.13- 20.0 ind/0.1 ha in the upland bogs, whereas common toad is the most abundant – 10.90-37.7 ind/ 0.1 ha in the agrocultural landscape and cultivated land. Other amphibians are considered to be rare or they are less frequently met and they ar...

A Twelve-Band Airborne Digital Video Imaging System (ADVIS)

This article describes an airborne digital video imaging system (ADVIS) and presents multispectral imagery to illustrate its potential use as a remote sensing research tool. The system was primarily designed to acquire multiband images for ascertaining spectral bands and/or band combinations to better characterize and assess natural resources. The ADVIS is comprised of 12 charge coupled device (CCD) analog video cameras and a computer equipped with a single multichannel digitizing board. The system cameras are equipped with various narrowband (6.5–12.6 nm bandwidths) interference filters to acquire images within the visible/near-infrared (NIR) (400–1000 nm) spectral waveband. The ADVIS multichannel capturing board is capable of obtaining 12 analog video inputs that are readily converted into digital images having 640 by 480 pixels resolution. The digitizing board has four RGB banks which have the capability of generating four synchronized real-time false color composite images from any selectable three-band combination among the 12 cameras, as keyed by the RGB inputs of the digitizing board. The computer system has a two GB storage capacity hard drive that can store 2000 RGB 24-bit color images. The system is unique because the quad real-time color composite imagery it provides is of adequate quality for assessing scenes of interest and there is no need for post-processing band registration immediately after the flight mission in order to evaluate the imagery. Also, the display of the quad images readily depicts which composite image(s) provides better differences among land-use cover types in the scene. This imagery, however, needs to be registered for image processing and analysis. The display of the black-and-white (B&W) image components (spectral bands) of the composite images provide basic information to assist in the interpretation of the color composites and to qualitatively understand the interaction of ecological parameters with the electromagnetic spectrum. The ADVIS multispectral image acquisition may determine the best band(s) for characterizing and/or detecting problems of the various natural resources.

Real-time airborne agricultural monitoring

In 1992 growers of high-value crops in central Wisconsin expressed an interest in using real-time remote sensing data for detecting crop stress. In response to this request, the Space Remote Sensing Center built a system based on work carried out by the USDA, ARS in Weslaco, Texas. This new system included a modification from analog to digital cameras that provided a means of overcoming previous barriers that inhibited real-time information delivery. These barriers include automated band to band registration, data calibration, and automated identification and retrieval of desired data frames. During the 1992 growing season weekly airborne acquisitions were attempted with 24–48-hr information delivery to the growers. Digital images were acquired for high value crops such as potatoes, sweet corn, cranberries, and peas. The system enabled detection of stresses such as freeze damage, irrigation problems, and Colorado potato beetle infestations. Experience gained during 1992 guided modification to the system to prepare for the 1993 growing season. This overall effort is helping prepare the market and technology for a real-time agriculture monitoring satellite.

Enzymatic multiplex DNA sequencing

The problem of reading DNA sequence films has been reformulated using an easily implemented, multiplex version of enzymatic DNA sequencing. By utilizing a uniquely tagged primer for each base-specific sequencing reaction, the four reactions can be pooled and electrophoresed in a single lane. This approach has been previously proposed for use with fluorescently labelled probes (1), and is analogous to the principle used in four-dye fluorescence sequencing except that the signals are resolved following electrophoresis (2). After transfer to a nylon membrane, images are obtained separately for each of the four reactions by hybridization using oligonucleotide probes. The images can then be superimposed to reconstitute a complete sequence pattern. In this way the correction of gel distortion effects and accurate band registration are considerably simplified, as each of the four base-specific ladders require very similar corrections. The methods therefore provide the basis for a second generation of more accurate and reliable film reading programs, as well as being useful for conventional multiplex sequencing. Unlike the original multiplex protocol (3), the approach described is suitable for small projects, as multiple cloning vectors are not used. Although more than one vector can be utilized, only a library of fragments cloned into any single phage, phagemid or plasmid vector is actually required, together with a set of tagged oligonucleotide primers.