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Overview |
DigitalGlobe’s WorldView-1 satellite is the most agile commercial satellite ever flown. The high-capacity, panchromatic imaging system features half-meter resolution imagery. The satellite is also equipped with state-of-the-art geolocation accuracy capabilities and exhibits stunning agility with rapid pointing and efficient in-track stereo collection.
WorldView-1 is designed to efficiently and accurately image large areas with industry-leading geolocatio n accuracy. The WorldView-1 spacecraft is capable of collecting up to 750,000 square kilometers (290,000 square miles) of imagery per day.
WorldView-1 Characteristics |
| Launch Information |
Date: September 18, 2007 Launch Vehicle: Delta II 7920 Launch Site: Vandenberg Air Force Base |
| Orbit |
Altitude: 496 kilometers Type: Sun synchronous, 10:30 am descending node Period: 94.6 minutes |
| Sensor Bands |
Panchromatic |
| Sensor Resolution (GSD = Ground Sample Distance) |
0.50 meters GSD at nadir 0.59 meters GSD at 25° off-nadir |
| NIIRS Equivalency |
NIIRS potential of greater than 5.0 |
| Dynamic Range |
11-bits per pixel |
| Swath Width |
17.6 kilometers at nadir |
| Pointing Accuracy & Knowledge |
Accuracy: <500 meters at image start and stop Knowledge: Supports geolocation accuracy below |
| Retargeting Agility |
Acceleration: 2.5 deg/s/s Rate: 4.5 deg/s Time to slew 300 kilometers: 10.5 seconds |
| Onboard Storage |
2199 gigabits solid state with EDAC |
| Max Viewing Angle / Accessible Ground Swath |
Nominally +/-45° off-nadir = 1036 km wide swath Higher angles selectively available |
| Per Orbit Collection |
331 gigabits |
| Max Contiguous Area Collected in a Single Pass |
60 x 110 km mono 30 x 110 km stereo |
| Revisit Frequency |
1.7 days at 1 meter GSD 4.6 days at 25° off-nadir or less (0.59 meter GSD) |
| Geolocation Accuracy (CE90) |
Geolocation Accuracy specification of 6.5m CE90% at nadir, with actual accuracy in the range of 4.0 – 5.5m CE90%, excluding terrain and off-nadir effects |
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| Product Types |
DigitalGlobe offers WorldView-1 Imagery Products in Basic, Standard, and Orthorectified
options. The levels of processing and geolocation accuracy for Basic and Standard are
shown in the table below.
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| Product Level |
Processing |
CE90 |
| Basic Imagery |
Sensor Corrected (Raw) |
6.5-meters* |
| Standard Imagery |
Georectified |
6.5-meters* |
*Measured using Image Support Data files and GCPs
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| Basic Imagery Products |
Basic Imagery products are the least processed of the WorldView-1 Imagery Products. Each strip in a Basic Imagery order is processed individually; therefore, multi-strip BasicImagery products are not mosaicked.
Processing: Basic Imagery products are radiometrically corrected and sensor corrected, but not projected to a plane using a map projection or datum. The sensor correction blends all pixels from all detectors into the synthetic array to form a single image. The resulting GSD varies over the entire product because the attitude & ephemeris slowly change during the imaging process.
Physical Structure: Basic Imagery products are delivered at full swath width, cut into 14km lengths. Full strip width is 17.6 km at nadir; the area that this width represents on the ground depends on the collection parameters (off-nadir angle, orientation of collection, etc). Note that depending on area ordered, the length of the last piece could be less than 14 km. There will be at least 1.8 km overlap between each 14 km length delivered.
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Physical characteristics – Basics imagery |
| Minimum orderable area |
25 sqkm archive/64 sqkm tasking |
| Minimum deliverable area |
1scene |
| Maximum orderable area (single order) |
50,000 km2 |
| Product framing |
Product are delivered at full swath width, cut into 14km length. Full strip width is 17.6km at nadir ; the area that this width represent on the ground depends on the collection parameters (off – nadir angle, orientation of collection, etc). |
| Final product physical structure |
Frame to full sensor width |
| Pan strip width (pixels) |
35,170 |
| Pan strip width (km, approximate at nadir) |
17.6 km |
| MS scene dimensions (pixels col, row) |
N/A |
| MS scene size ( approximate at nadir) |
N/A |
Processing specifications |
| Absolute geolocation accuracy (nadir) |
Geometrically raw, supplied image support data and user supplied DEM allows processing to 6.5m CE90% with actual accuracy in the range of 4.0 – 5.5m CE90%, excluding viewing geometry terrain displacement. |
| Additional geometric correction applied |
N/A |
| Geolocation information applied |
N/A |
| Applied terrain information |
N/A |
| Spatial mosnicing information |
N/A |
| Color balance applied |
N/A |
| Radiometric correction |
Relative radiometric response between detectors; non-responsive detector fill; conversion for absolute radiometry. |
| Sensor correction |
Internal detector geometry; optical distortion; scan distortion; line- rate variations. |
Product parameters |
| Product option |
Panchromatic only |
| Number of bits per pixel in delivered product |
8or 16 |
| Digital scaling method (applies to 8 bit only) |
Linear with a maximum value set to 255 |
| Resampling option |
4x4 cubic convolution (default);2x2 bilinear; nearest neighbor; 8 pt sinc; MTF kernel |
| Output pixel spacing |
As collected |
| Map projections |
N/A |
| Eliipsolds and datums |
N/A |
| Output alignment |
N/A |
| Cloud cover |
0-20% |
Delivery parameters |
| Output product delivery media option |
FTP pull, DVD, firewire |
| Image data format option |
NITF 2.0; NITF 2.1; GeoTIFF 1.0 |
| Image compression option |
N/A |
Image support data |
| ISD files supplied to customer |
Delivery (top level index) README file; layout file, shapefiles, browse image; product README, image metadata file, ephemeris file; attitude file; geometric calibration file;RPC00B file, license text file; tile map file |
| Spacecraft telemetry |
Refined attitude/ ephemeris(supplied with ISD) |
Characteristics of Worldview-1 Basic Imagery Products |
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Standard Imagery Products |
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Standard Imagery products are processed to a further extent than Basic Imagery. They are more suitable for users that require imagery in a familiar ground-based coordinate system (such as UTM Zone or State Plane).
Processing: Standard Imagery products are radiometrically corrected, sensor corrected, and projected to a plane using the map projection and datum of the customer's choice. All Standard Imagery products have uniform GSD throughout the entire product.
Physical Structure: Standard Imagery products are area based and may be ordered by the square kilometer. Standard Imagery products are delivered as one image file for each strip the order polygon intersects. If the order polygon intersects more than one strip, the imagery in each strip will be delivered as separate files, will not be mosaicked together to form a single image, and will not be radiometrically balanced. The delivered area for Standard Products is the order polygon is black-filled to the Minimum Bounding
Rectangle. Standard Imagery comes in two varieties:
Standard Imagery: Standard Imagery has a coarse DEM applied to it, which is used to correct for topographic relief with respect to the reference ellipsoid. The degree of normalization is relatively small, so while this product has terrain corrections, it is not considered orthorectified.
Ortho Ready Standard Imagery: Ortho Ready Standard Imagery has no topographic relief applied, making it suitable for orthorectification by the customer. Ortho Ready Standard Imagery is projected to an average elevation, either calculated from a terrain elevation model or can be supplied by the customer.
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| Physical characteristics - standard imagery |
| Minimum deliverable area |
25 sqkm archive/64 sqkm tasking |
| Maximum orderable area ( single order) |
50,000km2 |
| Product framed |
Area-based |
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Final product physical structure |
Blackfill to MBR surrounding the image pixels |
| Pan strip width (pixels) |
N/A |
| Pan strip width(km, approximate at nadir) |
N/A |
| MS scene dimensions (pixels col, row) |
N/A |
| MS scene size (approximate at nadir) |
N/A |
Processing specification |
| Absolute geolocation accuracy (nadir) |
Geolocation accuracy specification of 6.5m CE90% at nadir, with actual accuracy in the range of 4.0-5.5m CE90%, excluding terrain and off-nadir effects |
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Additional geometric correction applied |
Spacecraft orbit position and attitude uncertainty; earth rotation; earth curvature; panoramic distortion; terrain elevation(coarse) |
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Geolocaiton information applied |
Ephemeris and attitude; rotation and alignment to map projection |
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Applied terrain information |
None (ortho ready); coarse DEM (standard) |
| Spatial mosaicing applied |
N/A |
| Color balance applied |
N/A |
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Radiometric corrections |
Relative radiometric response between detectors; non-responsive detectors fill; conversion for absolute radiometry |
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Sensor corrections |
Internal detector geometry; optical distortion; scan distortion; line rate variations |
Product parameters |
| Product option |
Panchromatic only |
| Number of bits per pixel in delivered product |
8 or 16 |
| Digital scaling method ( applies to 8 bit only) |
Linear with a maximum value set to 255 |
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Resampling option |
4x4 cubic convolution (default); 2x2 bilinear; nearest neighbor; 8 pt sinc; MTF kernel
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| Dynamic range adjustment (DRA) option |
Contrast enhancement (8bit only) |
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Output tile size option |
None; 8k x 8k pixels; 14k x 14k pixels; 16k x 16k pixels |
| Output pixel option |
50 cm |
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Map projection |
See Quickbird Imagery Products-Products guide |
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Ellipsoids and datums |
See Quickbird Imagery Products guide-products guide |
| Output elingnment |
Rotated to Map North up |
| Cloud cover |
0-100% |
Delivery Parameters |
| Output product delivery media options |
FTP pull, DVD, firewire |
| Image data format option |
NITF 2.0; NITF 2.1; GeoTIFF 1.0 |
| Image compression option |
N/A |
Image support data |
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ISD files supplied to customer |
Delivery (top level index) README file, layout file, shapefiles, browse image, Product README, Image metadata file, geometric calibration file,RPC00B file, (OR2A only); license text file; bit map file |
| Spacecraft telemetry |
Refined attitude/ephemeris ( use to create product) |
Characteristics of Worldview-1 Basic Imagery Products |
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Orthorectified Imagery Products |
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Orthorectified Imagery products are GIS-ready and are used as image base maps for a wide variety of applications. These products can also be used for numerous applications that require a higher degree of absolute accuracy. As shown in Table , the product levels equate to different levels of processing and geolocation accuracy.
| Product Level |
Processing |
CE90 |
RMSE |
| Ortho 1:12,000 |
Orthorectified |
10.2-meters |
6.2-meters |
| Ortho 1:5000 |
Orthorectified |
4.23-meters |
2.6-meters |
| Ortho 1:4,800 |
Orthorectified |
4.1-meters |
2.5-meters |
| Custom Ortho |
Orthorectified |
variable* |
variable* |
* Accuracy of the Custom Ortho is determined by the accuracy and quality of customer supplied support data.
WorldView-1 Orthorectified Imagery Products and Associated Accuracies.
Processing: Orthorectified Imagery products are radio metrically corrected, sensor corrected, and orthorectified with a fine digital terrain model using the map projection and datum requested by the customer (reference QuickBird Imagery Products – Product Guide). For order polygons that require more than 1 strip, customers have the option to have their products mosaicked into a single product.
Orthorectified Imagery products require DEMs to remove relief displacement. Ground Control Points (GCPs) can also be used to improve the absolute accuracy. Before an order for an Orthorectified Imagery product is accepted, Digital Globe will determine whether it has the appropriate support data to make the desired product. The accuracy of the DEMs and/or GCPs required to make each product depends on the scale of the Orthorectified Imagery product ordered. Quotes for the support data will be provided on request (for locations where GCPs can be collected).
Digital Globe also offers customers the opportunity to order Custom Orthorectified Imagery products. To create these products Digital Globe uses customer provided support data to orthorectify WorldView-1 Imagery. There is no stated accuracy associated with the Custom Orthorectified Imagery product because the quality and accuracy of the finished product is directly dependent on the quality and accuracy of the support data. DEMs and GCPs are the most typical types of support data that customers provide to Digital Globe. Please contact Digital Globe for a complete list of acceptable types of support data and formats. |
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Physical characteristics – ortho imagery |
| Minmum deliverable area |
100 km2 |
| Maximum orderable area ( single order) |
50,00km2 |
| Product framing |
Area – based |
| Final product physical structure |
Blackfill to MBR surrounding the orderd image pixels |
| Pan strip width (pixels) |
N/A |
| Pan strip width (km, approximate at nadir) |
N/A |
| MS scene dimensions (pixel col, row) |
N/A |
| MS scene size (approximate at nadir) |
N/A |
Processing specifications |
| Absolute geolocation accuracy (nadir) |
1:12 000(without control),1:5000(with control),1:4800(with control) custom( with customer supplied control) |
| Additional geometric correction applied |
Spacecraft orbit position and attitude uncertainty; Earth rotation; Earth curvature; panoramic distortion; terrain elevation (fine) |
| Geolocation information applied |
Refined ephemeris and attitude; rotation and alignment to map projection |
| Applied terrain information |
Fine DEM |
| Spatial mosaicing applied |
Images mosaicked to minimize seamlines |
| Radiometric balance applied |
Yes |
| Radiometric correction |
Relative radiometric response between detectors; non – responsive detector fill; conversion for absolute radiometry |
| Sensor correction |
Internal detector geometry; optical distortion; scan distortion; line rate variations |
Product parameters |
| Product options |
Panchromatic only |
| Number bits per pixel in delivered product |
8 or 16 |
| Digital scaling method (applies to 8 bit only) |
Linear with a maximum value set to 255 |
| Resampling option |
4x4 cubic convolution (default); 2x2 bilinear; nearest neighbor; 8 pt sinc; MTF kernel |
| Dynamic range adjustment (DRA) option |
Contrast enhancement (8 bit only) |
| Output tile size option |
None; 8k x 8k pixels; 14k x 14k pixels; 16k x 16k pixels product units – customer specified (mosaic only) |
| Output pixel spacing |
50 cm |
| Map projections |
See quickbird imagery products- product guide |
| Ellipsoids and datums |
See quickbird imagery products- product guide |
Characteristics of Worldview -1 Orthorectified Imagery Products |
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