New sensors benchmark report on WorldView-3

Imagery collected by recently launched WorldView-3 satellite can be potentially used in The Common Agricultural Policy (CAP) image acquisition Campaign. The qualification and certificate is conducted by performing benchmarking tests namely, it has to be checked whether planimetric accuracy of produced orthoimagery does not exceed certain values regulated by JRC. Therefore, benchmarking tests were carried out on two WorldView-3 imagery acquired in October and November 2014. This report describes in detail how the tests were performed i.e. auxiliary data used, methodology and workflow as well as outcome from the Internal Quality Control. However, to make the tests objective, the orthoimagery was handed to JRC for External Quality Control which is a base for certification of the sensor. Such external QC has been performed by the JRC and included in Chapter 7.JRC.H.6-Digital Earth and Reference Dat

Mapping eucalyptus species using worldview 3 and random forest

Recent advances in remote sensing technologies have allowed the development of new innovative methodologies to obtain geospatial information about Eucalyptus genus distribution. This is an important task for forest stakeholders due to the high presence of this genus in forest plantations worldwide. Therefore, the next step in research should focus on exploring remote sensing possibilities to discern between Eucalytpus species. It would be an important step forward in forest management since different Eucalyptus species present different characteristics and properties that imply different management plans and industrial usages. This study accomplish the classification of E. nitens and E. globulus, the most common Eucalyptus species in the Iberian Peninsula. Worldview-3 images and random forest are used in a forest area placed in Galicia (Northwest of Spain). The differentiation of Eucalyptus species resulted in a producer’s accuracy of 84% and a users’ accuracy of 70% for E. nitens, while for E. globulus accuracy metrics did not reach 70%. The most important bands in the classification were the coastal blue and the blue, followed by the red related ones. The resulting unequal accuracy metrics might be caused by an imbalanced presence of both species in the selected study area. Therefore, further studies might be developed in different locations

Vertical Artifacts in High-Resolution WorldView-2 and Worldview-3 Satellite Imagery of Aquatic Systems

Satellite image artefacts are features that appear in an image but not in the original imaged object and can negatively impact the interpretation of satellite data. Vertical artefacts are linear features oriented in the along-track direction of an image system and can present as either banding or striping; banding are features with a consistent width, and striping are features with inconsistent widths. This study used high-resolution data from DigitalGlobeʻs (now Maxar) WorldView-3 satellite collected at Lake Okeechobee, Florida (FL), on 30 August 2017. This study investigated the impact of vertical artefacts on both at-sensor radiance and a spectral index for an aquatic target as WorldView-3 was primarily designed as a land sensor. At-sensor radiance measured by six of WorldView-3ʻs eight spectral bands exhibited banding, more specifically referred to as non-uniformity, at a width corresponding to the multispectral detector sub-arrays that comprise the WorldView-3 focal plane. At-sensor radiance measured by the remaining two spectral bands, red and near-infrared (NIR) #1, exhibited striping. Striping in these spectral bands can be attributed to their time delay integration (TDI) settings at the time of image acquisition, which were optimized for land. The impact of vertical striping on a spectral index leveraging the red, red edge, and NIR spectral bands—referred to here as the NIR maximum chlorophyll index (MCINIR)—was investigated. Temporally similar imagery from the European Space Agencyʻs Sentinel-3 and Sentinel-2 satellites were used as baseline references of expected chlorophyll values across Lake Okeechobee as neither Sentinel-3 nor Sentinel-2 imagery showed striping. Striping was highly prominent in the MCINIR product generated using WorldView-3 imagery, as noise in the at-sensor radiance exceeded any signal of chlorophyll in the image. Adjusting the image acquisition parameters for future tasking of WorldView-3 or the functionally similar WorldView-2 satellite may alleviate these artefacts. To test this, an additional WorldView-3 image was acquired at Lake Okeechobee, FL, on 26 May 2021 in which the TDI settings and scan line rate were adjusted to improve the signal-to-noise ratio. While some evidence of non-uniformity remained, striping was no longer noticeable in the MCINIR product. Future image tasking over aquatic targets should employ these updated image acquisition parameters. Since the red and NIR #1 spectral bands are critical for inland and coastal water applications, archived images not collected using these updated settings may be limited in their potential for analysis of aquatic variables that require these two spectral bands to derive

BATHYMETRY FROM WORLDVIEW-3 SATELLITE DATA USING RADIOMETRIC BAND RATIO

The use of optical satellite sensors allows to obtain bathymetry data on large area ina short time and in a cheap way. In addition, in particular places where it is difficult to carry out the survey by classic methods, the bathymetry from satellite data can be the only mode to obtain the depth of the backdrop. So, the aim of this research paper is to analyse the potential of the eight bands and the very high resolution of the commercial satellite WorldView-3 (WV-3) in order to obtain bathymetric data. Using WV-3 satellite data and the Stumpf method, the paper intends to investigate the possibility of obtaining bathymetric data in a specific area where the water is not particularly clear. To achieve this goal, in Geographic Information System (GIS) environment, several algorithms have been developed. The comparison between the results and the reference bathymetric data shows a huge potential of the WV-3 satellite data. The area of study concerns the port area of the city of Lisbon and a part of the river Rio Tejo, in Portugal

Georeferencing accuracy analysis of a single worldview-3 image collected over Milan

The use of rational functions has become a standard for very high-resolution satellite imagery (VHRSI). On the other hand, the overall geolocalization accuracy via direct georeferencing from on board navigation components is much worse than image ground sampling distance (predicted < 3.5 m CE90 for WorldView-3, whereas GSD = 0.31 m for panchromatic images at nadir). This paper presents the georeferencing accuracy results obtained from a single WorldView-3 image processed with a bias compensated RPC camera model. Orientation results for an image collected over Milan are illustrated and discussed for both direct and indirect georeferencing strategies as well as different bias correction parameters estimated from a set of ground control points. Results highlight that the use of a correction based on two shift parameters is optimal for the considered dataset

Integrasi Algoritma Lacunarity dan Analisis Penajaman Citra Worldview 3 untuk Penentuan Prioritas dan Jenis Tindak Penanganan Kawasan Kumuh (Kasus di Kecamatan Wonokromo, Kota Surabaya)

Perkembangan jumlah penduduk dan meningkatnya pergerakan penduduk di suatu kota akan menciptakan pertumbuhan kawasan permukiman – permukiman baru. Kemudahan akses terhadap lokasi pekerjaan dan fasilitas umum dapat memicu munculnya hunian – hunian ilegal di beberapa kawasan tertentu. Data penginderaan jauh mampu menyajikan informasi spasial secara detail sehingga dapat digunakan sebagai sumber data dalam mengetahui kondisi permukiman perkotaan. Tujuan dari penelitian ini adalah (1) mengetahui akurasi yang dihasilkan citra Worldview 3 dalam deteksi dan identifikasi permukiman kumuh dengan algoritma lacunarity, dan (2) menentukan prioritas dan jenis tindak penanganan kawasan kumuh di Kecamatan Wonokromo.Metode penelitian yang digunakan adalah metode penginderaan jauh dengan analisis kualitatif dan kuantitatif terhadap variabel yang diuji, yaitu algoritma lacunarity dan variabel kekumuhan PU. Hasil Penajaman Citra Worldview 3 (perekaman 27 Juli 2015) digunakan untuk interpretasi pemanfaatan blok permukiman. Survei lapangan dilakukan pada 5 April hingga 10 Mei 2016 untuk menguji hasil klasifikasi dan pemanfaatan blok permukiman, deteksi kekumuhan algoritma lacunarity, dan deteksi kekumuhan PU. Hasil akhir penelitian ini adalah akurasi deteksi algoritma lacunarity, peta lokasi kumuh di Kecamatan Wonokromo, peringkat prioritas penanganan, dan jenis tindak penanganan kawasan kumuh.Hasil penelitian menunjukkan bahwa citra Worldview 3 memberikan akurasi sedang pada deteksi permukiman kumuh (sebesar 33,3%, pada jendela bergerak 7x7, sebesar 50,0% pada jendela bergerak 5x5, dan 58,3% pada jendela bergerak 3x3). Semakin kecil ukuran jendela bergerak yang digunakan meningkatkan kemampuan algoritma dalam mendeteksi kekumuhan. Prioritas penanganan tingkat pertama berada di Kelurahan Sawunggaling dan Darmo. Jenis tindak penanganan yang digunakan menggunakan pendekatan property development pada semua lokasi kumuh di Kecamatan Wonokromo

Pansharpening techniques to detect mass monument damaging in Iraq

The recent mass destructions of monuments in Iraq cannot be monitored with the terrestrial survey methodologies, for obvious reasons of safety. For the same reasons, it’s not advisable the use of classical aerial photogrammetry, so it was obvious to think to the use of multispectral Very High Resolution (VHR) satellite imagery. Nowadays VHR satellite images resolutions are very near airborne photogrammetrical images and usually they are acquired in multispectral mode. The combination of the various bands of the images is called pan-sharpening and it can be carried on using different algorithms and strategies. The correct pansharpening methodology, for a specific image, must be chosen considering the specific multispectral characteristics of the satellite used and the particular application. In this paper a first definition of guidelines for the use of VHR multispectral imagery to detect monument destruction in unsafe area, is reported. The proposed methodology, agreed with UNESCO and soon to be used in Libya for the coastal area, has produced a first report delivered to the Iraqi authorities. Some of the most evident examples are reported to show the possible capabilities of identification of damages using VHR images