scholarly journals Radiometric Calibration Targets for the Mastcam-Z Camera on the Mars 2020 Rover Mission

2020 ◽  
Vol 216 (8) ◽  
Author(s):  
K. M. Kinch ◽  
M. B. Madsen ◽  
J. F. Bell ◽  
J. N. Maki ◽  
Z. J. Bailey ◽  
...  
Keyword(s):  
Permanent Magnets ◽  
Central Area ◽  
Image Data ◽  
Radiometric Calibration ◽  
Martian Surface ◽  
Primary Target ◽  
Calibration Target ◽  
Black Paint ◽  
Related Information ◽  
Ceramic Color

AbstractThe Mastcam-Z Camera is a stereoscopic, multispectral camera with zoom capability on NASA’s Mars-2020 Perseverance rover. The Mastcam-Z relies on a set of two deck-mounted radiometric calibration targets to validate camera performance and to provide an instantaneous estimate of local irradiance and allow conversion of image data to units of reflectance (R∗ or I/F) on a tactical timescale. Here, we describe the heritage, design, and optical characterization of these targets and discuss their use during rover operations. The Mastcam-Z primary calibration target inherits features of camera calibration targets on the Mars Exploration Rovers, Phoenix and Mars Science Laboratory missions. This target will be regularly imaged during flight to accompany multispectral observations of the martian surface. The primary target consists of a gold-plated aluminum base, eight strong hollow-cylinder Sm2Co17 alloy permanent magnets mounted in the base, eight ceramic color and grayscale patches mounted over the magnets, four concentric, ceramic grayscale rings and a central aluminum shadow post (gnomon) painted with an IR-black paint. The magnets are expected to keep the central area of each patch relatively free of Martian aeolian dust. The Mastcam-Z secondary calibration target is a simple angled aluminum shelf carrying seven vertically mounted ceramic color and grayscale chips and seven identical, but horizontally mounted ceramic chips. The secondary target is intended to augment and validate the calibration-related information derived from the primary target. The Mastcam-Z radiometric calibration targets are critically important to achieving Mastcam-Z science objectives for spectroscopy and photometric properties.

scholarly journals CALIPSO lidar calibration at 1064 nm: version 4 algorithm

2019 ◽  
Vol 12 (1) ◽  
pp. 51-82 ◽  
Author(s):  
Mark Vaughan ◽  
Anne Garnier ◽  
Damien Josset ◽  
Melody Avery ◽  
Kam-Pui Lee ◽  
...  
Keyword(s):  
Molecular Model ◽  
Signal To Noise Ratio ◽  
High Spectral Resolution ◽  
Orthogonal Polarization ◽  
Radiometric Calibration ◽  
Calibration Target ◽  
Full Account ◽  
High Spectral Resolution Lidar ◽  
532 Nm ◽  
Calibration Coefficients

Abstract. Radiometric calibration of space-based elastic backscatter lidars is accomplished by comparing the measured backscatter signals to theoretically expected signals computed for some well-characterized calibration target. For any given system and wavelength, the choice of calibration target is dictated by several considerations, including signal-to-noise ratio (SNR) and target availability. This paper describes the newly implemented procedures used to calibrate the 1064 nm measurements acquired by CALIOP (i.e., the Cloud-Aerosol Lidar with Orthogonal Polarization), the two-wavelength (532 and 1064 nm) elastic backscatter lidar currently flying on the Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observations (CALIPSO) mission. CALIOP's 532 nm channel is accurately calibrated by normalizing the molecular backscatter from the uppermost aerosol-free altitudes of the CALIOP measurement region to molecular model data obtained from NASA's Global Modeling and Assimilation Office. However, because CALIOP's SNR for molecular backscatter measurements is prohibitively lower at 1064 nm than at 532 nm, the direct high-altitude molecular normalization method is not a viable option at 1064 nm. Instead, CALIOP's 1064 nm channel is calibrated relative to the 532 nm channel using the backscatter from a carefully selected subset of cirrus cloud measurements. In this paper we deliver a full account of the revised 1064 nm calibration algorithms implemented for the version 4.1 (V4) release of the CALIPSO lidar data products, with particular emphases on the physical basis for the selection of “calibration quality” cirrus clouds and on the new averaging scheme required to characterize intra-orbit calibration variability. The V4 procedures introduce latitudinally varying changes in the 1064 nm calibration coefficients of 25 % or more, relative to previous data releases, and are shown to substantially improve the accuracy of the V4 1064 nm attenuated backscatter coefficients. By evaluating calibration coefficients derived using both water clouds and ocean surfaces as alternate calibration targets, and through comparisons to independent, collocated measurements made by airborne high spectral resolution lidar, we conclude that the CALIOP V4 1064 nm calibration coefficients are accurate to within 3 %.

scholarly journals Spectral and Radiometric Calibration of the Next Generation Airborne Visible Infrared Spectrometer (AVIRIS-NG)

2019 ◽  
Vol 11 (18) ◽  
pp. 2129 ◽  
Author(s):  
John W. Chapman ◽  
David R. Thompson ◽  
Mark C. Helmlinger ◽  
Brian D. Bue ◽  
Robert O. Green ◽  
...  
Keyword(s):  
Infrared Imaging ◽  
Image Data ◽  
Radiometric Calibration ◽  
Next Generation ◽  
Imaging Spectrometer ◽  
In Situ Data ◽  
Novel Approach ◽  
Infrared Spectrometer ◽  
Calibration Techniques ◽  
Spectrometer Data

We describe advanced spectral and radiometric calibration techniques developed for NASA’s Next Generation Airborne Visible Infrared Imaging Spectrometer (AVIRIS-NG). By employing both statistically rigorous analysis and utilizing in situ data to inform calibration procedures and parameter estimation, we can dramatically reduce undesirable artifacts and minimize uncertainties of calibration parameters notoriously difficult to characterize in the laboratory. We describe a novel approach for destriping imaging spectrometer data through minimizing a Markov Random Field model. We then detail statistical methodology for bad pixel correction of the instrument, followed by the laboratory and field protocols involved in the corrections and evaluate their effectiveness on historical data. Finally, we review the geometric processing procedure used in production of the radiometrically calibrated image data.

scholarly journals SITE SELECTION AND EVALUATION OF CHINA'S NEW RADIOMETRIC CALIBRATION TEST SITES

2020 ◽  
Vol XLII-3/W10 ◽  
pp. 511-520
Author(s):  
X. K. Hu ◽  
H. L. Gao ◽  
T. H. Cheng ◽  
S. H. Tang ◽  
L. Liu ◽  
...  
Keyword(s):  
Site Selection ◽  
Spatial Scales ◽  
Spectral Characteristics ◽  
Satellite Image ◽  
Image Data ◽  
Surface Characteristics ◽  
Surface Damage ◽  
Test Site ◽  
Radiometric Calibration ◽  
National Test

Abstract. The ideal radiometric calibration site is the basis for achieving on-orbit radiometric calibration. At present, China mainly uses the Dunhuang national test site for on-orbit radiometric calibration. However, the Dunhuang national test site has a shortage of ground objects and surface damage, and it is urgent to select and evaluate the new calibration sites. By analyzing the calibration site selection requirements, three new radiometric calibration sites were selected in Dunhuang and Golmud. Obtaining high-resolution satellite image data of each calibration site and evaluating the spatial uniformity of the site on different spatial scales. The radiometric stability of the sites is evaluated using the long-term sequence of Landsat8 image data from 2013 to 2019. Atmospheric and surface tests were carried out at various sites in August 2019, and atmospheric information and ground spectral data were obtained to evaluate the spectral characteristics of the sites. The surface directional characteristics of the sites are evaluated by using MODIS images at different angles in sunny weather on adjacent dates. Obtaining MOD05 water vapor products from 2013 to 2019 of each calibration site and conducting monthly statistics. The number of sunny days at each calibration site is counted and the drought conditions of the site are evaluated. The results show that the three new radiometric calibration sites have uniform and stable surface characteristics and atmospheric characteristics, and are suitable for on-orbit radiometric calibration of satellite sensors, which provides a reference for the location and evaluation of future calibration sites.

scholarly journals The Use of TERRA-ASTER Satellite for Landslide Detection

Geosciences ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 258
Author(s):  
Filippo Vecchiotti ◽  
Nils Tilch ◽  
Arben Kociu
Keyword(s):  
Vegetation Change ◽  
Central Area ◽  
Image Data ◽  
Weather Conditions ◽  
Optical Data ◽  
Visual Interpretation ◽  
Aerial Photos ◽  
Medium Resolution ◽  
Before And After ◽  
Very High

In August 2005, numerous shallow landslides occurred in the region of Vorarlberg (Austria), particularly induced by unfavourable event-related weather conditions. Two scenes of TERRA-ASTER sensor were used for the identification of the vegetation change induced by the landslides. The focus of this study is the establishment of a reliable method, comparable to aerial-photo visual interpretation standards, able to identify accurately landslides by processing a series of medium-resolution remote sensing optical data, before and after a catastrophic event. A very intuitive workflow for a semi-automatic image classification for the detection of landslide-induced change on the image data is proposed. The accuracy and validation assessment was carried out by means of a landslide (aerial-photos derived) inventory. By taking into account the central area of investigation, the landslide detection method, which adopted an innovative double classification workflow (a first supervised followed by an unsupervised algorithm), delivered a very high producer accuracy (81.5%) coupled to a more-than-acceptable user accuracy (68.9%) and kappa coefficient (72.9%).

scholarly journals PERFORMANCE ASSESSMENT AND GEOMETRIC CALIBRATION OF RESOURCESAT-2

2016 ◽  
Vol XLI-B1 ◽  
pp. 237-244
Author(s):  
P. V. Radhadevi ◽  
S. S. Solanki ◽  
A. Akilan ◽  
M. V. Jyothi ◽  
V. Nagasubramanian
Keyword(s):  
Accuracy Assessment ◽  
Image Data ◽  
System Level ◽  
Radiometric Calibration ◽  
Location Accuracy ◽  
Geometric Calibration ◽  
Geometry Model ◽  
Ground Control Points ◽  
Datum Transformation ◽  
The Stability

Resourcesat-2 (RS-2) has successfully completed five years of operations in its orbit. This satellite has multi-resolution and multi-spectral capabilities in a single platform. A continuous and autonomous co-registration, geo-location and radiometric calibration of image data from different sensors with widely varying view angles and resolution was one of the challenges of RS-2 data processing. On-orbit geometric performance of RS-2 sensors has been widely assessed and calibrated during the initial phase operations. Since then, as an ongoing activity, various geometric performance data are being generated periodically. This is performed with sites of dense ground control points (GCPs). These parameters are correlated to the direct geo-location accuracy of the RS-2 sensors and are monitored and validated to maintain the performance. This paper brings out the geometric accuracy assessment, calibration and validation done for about 500 datasets of RS-2. The objectives of this study are to ensure the best absolute and relative location accuracy of different cameras, location performance with payload steering and co-registration of multiple bands. This is done using a viewing geometry model, given ephemeris and attitude data, precise camera geometry and datum transformation. In the model, the forward and reverse transformations between the coordinate systems associated with the focal plane, payload, body, orbit and ground are rigorously and explicitly defined. System level tests using comparisons to ground check points have validated the operational geo-location accuracy performance and the stability of the calibration parameters.

scholarly journals Overcoming the Challenges of Thermal Infrared Orthomosaics Using a Swath-Based Approach to Correct for Dynamic Temperature and Wind Effects

2021 ◽  
Vol 13 (16) ◽  
pp. 3255 ◽  
Author(s):  
Yoann Malbéteau ◽  
Kasper Johansen ◽  
Bruno Aragon ◽  
Samir K. Al-Mashhawari ◽  
Matthew F. McCabe
Keyword(s):  
Surface Temperature ◽  
Rapid Development ◽  
Image Data ◽  
Surface Characteristics ◽  
Thermal Infrared ◽  
Radiometric Calibration ◽  
Agricultural Field ◽  
Infrared Sensors ◽  
Flight Direction ◽  
Significant Difference

The miniaturization of thermal infrared sensors suitable for integration with unmanned aerial vehicles (UAVs) has provided new opportunities to observe surface temperature at ultra-high spatial and temporal resolutions. In parallel, there has been a rapid development of software capable of streamlining the generation of orthomosaics. However, these approaches were developed to process optical and multi-spectral image data and were not designed to account for the often rapidly changing surface characteristics inherent in the collection and processing of thermal data. Although radiometric calibration and shutter correction of uncooled sensors have improved, the processing of thermal image data remains difficult due to (1) vignetting effects on the uncooled microbolometer focal plane array; (2) inconsistencies between images relative to in-flight effects (wind-speed and direction); (3) unsuitable methods for thermal infrared orthomosaic generation. Here, we use thermal infrared UAV data collected with a FLIR-based TeAx camera over an agricultural field at different times of the day to assess inconsistencies in orthophotos and their impact on UAV-based thermal infrared orthomosaics. Depending on the wind direction and speed, we found a significant difference in UAV-based surface temperature (up to 2 °C) within overlapping areas of neighboring flight lines, with orthophotos collected with tail wind being systematically cooler than those with head wind. To address these issues, we introduce a new swath-based mosaicking approach, which was compared to three standard blending modes for orthomosaic generation. The swath-based mosaicking approach improves the ability to identify rapid changes of surface temperature during data acquisition, corrects for the influence of flight direction relative to the wind orientation, and provides uncertainty (pixel-based standard deviation) maps to accompany the orthomosaic of surface temperature. It also produced more accurate temperature retrievals than the other three standard orthomosaicking methods, with a root mean square error of 1.2 °C when assessed against in situ measurements. As importantly, our findings demonstrate that thermal infrared data require appropriate processing to reduce inconsistencies between observations, and thus, improve the accuracy and utility of orthomosaics.

scholarly journals Current achievements and future developments of a novel AI based visual monitoring of beehives in ecotoxicology and for the monitoring of landscape structures

2020 ◽  
Author(s):  
Frederic Tausch ◽  
Katharina Schmidt ◽  
Matthias Diehl
Keyword(s):  
Honey Bees ◽  
Large Scale ◽  
Image Data ◽  
Visual Monitoring ◽  
Future Developments ◽  
Related Information ◽  
The Central Nervous System ◽  
Visual Monitoring System ◽  
Study Designs ◽  
Shed Light

Abstract in EnglishHoney bees are valuable bio-indicators. As such, they hold a vast potential to help shed light on the extent and interdependencies of factors influencing the decline in the number of insects. However, to date this potential has not yet been fully leveraged, as the production of reliable data requires large-scale study designs, which are very labour intensive and therefore costly.A novel Artificial Intelligence (AI) based visual monitoring system could enable the partial automatization of data collection on activity, forager loss and impairment of the central nervous system. The possibility to extract features from image data could prospectively also allow an assessment of pollen intake and a differentiation of dead bees, drones and worker bees as well as other insects such as wasps or hornets.The technology was validated in different studies with regards to its scalability and its ability to extract motion and feature related information.The prospective possibilities were analyzed regarding their potential to enable advances both within ecotoxicological research and the monitoring of pollinator habitats.

scholarly journals Topographic mapping of the Mars MC quadrangles using HRSC data

2021 ◽  
Author(s):  
Elke Kersten ◽  
Klaus Gwinner ◽  
Gregory Michael ◽  
Alexander Dumke ◽  
Ralf Jaumann
Keyword(s):  
High Resolution ◽  
Image Data ◽  
Landing Site ◽  
Planetary Science ◽  
Space Science ◽  
Topographic Map ◽  
Martian Surface ◽  
Global Mapping ◽  
Science Conference ◽  
Map Series

<p>The High Resolution Stereo Camera (HRSC) of ESA’s Mars Express mission [1, 2] is still running nominally and delivering new image strips to fill remaining gaps that lead to a contiguous coverage of the Martian surface at high resolution stereo. As a push broom scanning instrument with nine CCD line detectors mounted in parallel, its unique feature is the ability to obtain along-track stereo images and four colors during a single orbital pass. Thus, panchromatic stereo and color images from single orbits of the HRSC have been used to produce digital terrain models (DTMs) and orthoimages of the Martian surface since 2004 [3].</p><p>Since 2010 new HRSC multi-orbit data products have been generated, which have been developed into a global mapping program organized into MC-30 half-tiles, since 2014 [4,5]. Based on continuous coverage of an area, regional DTMs and orthomosaics can be produced by combining image data from multiple orbits using specifically adapted techniques for block-adjustment, DTM interpolation and image equalization [6]. The resulting DTMs and color orthomosaics are the baseline for a controlled topographic map series of Mars. The extents of the regional products follow the MC-30 (Mars Chart) global mapping scheme of Greeley and Batson [7]. For the generation of the DTMs and color mosaics, the MC-30 quadrangles are further divided into East (E) and West (W). In parallel to the completion of the first half-tile DTM and color mosaic (MC-11-E) we developed a concept for a topographic map series of Mars [8,9]. To limit data volumes and map sizes, each quadrangle is subdivided into eight tiles (i.e. each half-tile into four tiles). The map scale of 1:700,000 is a compromise between the high DTM and orthomosaic resolution of 50 m/pxl and an acceptable hardcopy format of about 1 m in width to 2 m in height (≜14 pxl/mm). MC-11 was selected to be produced first because it contains the finally selected landing site, Oxia Planum, of ESA’s ExoMars mission with the Rosalind Franklin rover. After MC-11, the Global Topography and Mosaics Task Group (GTMTG) of the HRSC Science Team focussed on MC-13, which hosts the landing site of the Perseverance rover from NASA’s Mars 2020 mission, Jezero crater. The next HRSC MC quadrangles will also be equatorial ones (i.e. 19 and 20).</p><p>All maps are available for the public at the HRSC team website (http://hrscteam.dlr.de/HMC30/index.html).</p><p>[1] Neukum, G., et al., ESA Special Publication, 1240, pp. 17-36, 2004. [2] Jaumann, R., et al., Planetary and Space Science 55, pp. 928-952, 2007. [3] Gwinner, K., et al., Earth and Planetary Science Letters, 294, pp. 506-519, 2010. [4] Gwinner, K, et al., 41st Lunar and Planetary Science Conference, #2727, 2010. [5] Dumke, A., et al., Lunar and Planetary Science Conference, #1533, 2010. [6] Gwinner, K. et al., Planetary and Space Science, 126, pp. 93-138, 2016. [7] Greeley, R. and Batson, G., Planetary Mapping, Cambridge University Press, Cambridge, 1990. [8] Schulz, K., Bachelor Thesis, Beuth Hochschule für Technik Berlin, 2017. [9] Kersten, E., et al., EPSC Abstracts Vol. 12, EPSC2018-352, 2018.</p>

scholarly journals A 3D Scan Model and Thermal Image Data Fusion Algorithms for 3D Thermography in Medicine

2017 ◽  
Vol 2017 ◽  
pp. 1-9 ◽  
Author(s):  
Adam Chromy ◽  
Ondrej Klima
Keyword(s):  
Data Fusion ◽  
Spatial Data ◽  
Thermal Imaging ◽  
3D Model ◽  
Image Data ◽  
Point Clouds ◽  
Thermal Image ◽  
The Body ◽  
Related Information ◽  
Application Potential

Objectives. At present, medical thermal imaging is still considered a mere qualitative tool enabling us to distinguish between but lacking the ability to quantify the physiological and nonphysiological states of the body. Such a capability would, however, facilitate solving the problem of medical quantification, whose presence currently manifests itself within the entire healthcare system. Methods. A generally applicable method to enhance captured 3D spatial data carrying temperature-related information is presented; in this context, all equations required for other data fusions are derived. The method can be utilized for high-density point clouds or detailed meshes at a high resolution but is conveniently usable in large objects with sparse points. Results. The benefits of the approach are experimentally demonstrated on 3D thermal scans of injured subjects. We obtained diagnostic information inaccessible via traditional methods. Conclusion. Using a 3D model and thermal image data fusion allows the quantification of inflammation, facilitating more precise injury and illness diagnostics or monitoring. The technique offers a wide application potential in medicine and multiple technological domains, including electrical and mechanical engineering.

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