Introduction

The ExtractNIRImages service will take a point or polygon and return the near-infrared (NIR) band within one or more color-shifted near-infrared (CIR) images, depending on the parameters of the request. Because the near-infrared band is outside of the visible spectrum, it is necessary to represent the near-infrared band using one of the visible spectrum colors (red, green or blue) using color-shifting. The resulting color-infrared (CIR) image represents the infrared, red and green (IRG) bands as:

• near-infrared band as red

• red band as green

• green band as blue.

• blue band is not returned

Despite being displayed as red, the near-infrared band contains accurate NIR data and can be used for many applications, including:

• See through smoke (in combination with dynamic range processing)

• Normalized difference vegetation indexing (NDVI)

• Analyze agricultural fields (e.g. growth rate, irrigation/fertilizer use)

• Classify land use (vegetated, non-vegetated, water, etc.)

• Disaster assessment (identify living/dead vegetation)

Technical Details

The ExtractNIRImages service is accessed by specifying the point (latitude and longitude) or polygon bounding box (well-known-text). Depending on parameters, this service will return the whole image or a portion of the image. The portion of the image is dimensioned either by request parameters width and height and centered on the requested point when using the xcoordinate and ycoordinate or by the request parameter crop when using the wtk parameter. 

Output Image Specifications:

• 8-bit depth

• 7.5 or 20 cm centimeter resolution (layer dependent)

• CIR color shift RGB → IRG:

  • NIR = R

  • Red = G

  • Green = B

• Jpeg image format

• Output Format: Jpeg images in a compressed folder

  • Folder Name: {layer parameter}.zip

  • Image Name: {year}~{AOI name}~{camera orientation}~{image name}.jpg

Output:

Open

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RGB representation

Open

RGB representation

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Open

Metadata (in JSON format):

[{"requested_point_wkt":"POINT(7761.811630220274 4890.897192878125)","gsd":0.0752518773297423,"image_id":"2019~us-mn-minneapolis-2019~images~NW_20190808_155443_92_27F14C5CEC6930E_irg","processing_date":"2021-06-21T23:18:39","processing_toolset_version":"3.3.0","capture_date":"2019-08-08T15:54:43","original_image_name":"nadir/22194-lvl02-color.tif","original_shot_id":"22194-Lvl02-Color","flight_line_id":"1","utm_zone":"15N","camera_pos_x":479555.9888,"camera_pos_y":4977822.573,"camera_z":1448.63501,"ground_z":262.011597,"omega":-0.001688315042463806,"phi":0.008293094654953778,"kappa":1.6478486375884165,"centre_wkt":"POINT(-93.25930679 44.95352711)","centre_wkt_latlon":"POINT(-93.25930679 44.95352711)","bbox_wkt":"POLYGON((-93.26292109 44.94873433,-93.26394805 44.9578427,-93.25570339 44.95830455,-93.25467894 44.94922342,-93.26292109 44.94873433))","bbox_wkt_latlon":"POLYGON((-93.26292109 44.94873433,-93.26394805 44.9578427,-93.25570339 44.95830455,-93.25467894 44.94922342,-93.26292109 44.94873433))","orientation":"I","projectname":"us-mn-minneapolis-2019","copyrightsentence":"VEXCEL_IMAGING_INC","processingcenter":"","layername":"bluesky-ultra","dtmfile":"","cameratechnology":"VEXCEL","projectext":"us-mn-minneapolis-2019","raster_size_width":13470.0,"raster_size_height":8670.0,"pixel_size":0.0052,"focal_length":82.0,"pp0_x":0.0,"pp0_y":0.0,"k0":0.0,"k1":0.0,"k2":0.0,"k3":0.0,"p1":0.0,"p2":0.0,"b1":0.0,"b2":0.0,"camera_name":"0","id":365612518,"max_zoom":0,"min_zoom":7,"tile_size_x":256,"tile_size_y":256,"relationPolygonInImage":0.0,"relationImageInPolygon":0.0}]

RGB representation

Open