Generate Orthophotos

Feature Description

Digital Orthophoto Map (DOM), referred to as orthophoto, is an image dataset generated by vertically projecting aerial or space imagery. During vertical projection, the system eliminates geometric distortions caused by terrain relief, camera tilt, and other factors, so that the orthophoto has uniform geometric accuracy. At the same time, the orthophoto can be seamlessly overlaid with maps, vector data, etc., providing reliable support for precise spatial analysis and measurement. Generating orthophotos is the process of outputting these processed image datasets.

In production workflows, only the panchromatic orthophoto is output by default.

Parameter Description

Parameter Name Parameter Interpretation Parameter Type
Dataset

Displays the original image used to generate the panchromatic orthophoto. Not editable.

 DatasetMosaic
Export Directory Uses the Processing path parameter in Set Image Path. Not editable. File
Resolution Type

Specifies the method for determining the output image resolution. Default is Original resolution.

  • Original resolution: Preserves the original resolution of the input image.
  • Fixed Value: Uses an input fixed value as the output image resolution.
  • Custom: Outputs different resolutions based on different satellite sensor types. After selecting Custom, the Custom Resolution: dialog box will appear. You can click the Add button on the toolbar to add a new row. Then click the cell in the Satellite sensor type column to select the sensor type. Finally, enter the corresponding resolution for the sensor type in the cell of the Resolution column.
    Note:
    • If the corresponding satellite sensor type is not found, select the USEDEFINE option. After selecting this option, the system will use the resolution corresponding to USEDEFINE to output data for all unsupported satellite sensor types.
    • If processing image data from multiple satellite sensor types (e.g., ZY3, GF-2, LandSat) simultaneously, but only setting the resolution for one satellite sensor type (e.g., only ZY3), then images of other satellite sensor types (e.g., GF-2 and LandSat) will be output using their original resolution.
 OrthoRatioType
Coordinate System Settings Uses the Output coordinate system parameter in Set Image Path. Not editable. PrjCoordSys
Output Format Uses the Output format parameter in Set Image Path. Not editable. FileType
Compression Method Uses the Compression method parameter in Set Image Path. Not editable. CompressMethod
Downscale to 8-Bit Unsigned

Specifies whether to convert the pixel format of the image to 8-bit unsigned before output.

Default is unchecked, meaning the pixel format of the image is not converted, and the output uses the original image's pixel format to ensure no loss of data precision.

If checked, the output image's pixel format will be converted to 8-bit unsigned according to the specified stretch method. This processing method can reduce storage space and improve processing efficiency, but may cause overexposure or information loss in the image, thereby affecting subsequent imagery and analysis.

 Boolean
Stretch Method Available after checking Downscale to 8-Bit Unsigned. Default is Percent Clip, and also provides Minimum Maximum, Gaussian, Gamalashin, Histogram Equalization, and Logarithmic Stretch. For more information on methods, refer to Image Stretching Method. DesktopImageStretchingType
Minimum Percentage

Available when Stretch method is Percent Clip. Default is 1.

 Double
Maximum Percentage Available when Stretch method is Percent Clip. Default is 99. Double
Gaussian Standard Deviation Coefficient Available when Stretch method is Gaussian. Default is 3. Integer
Gamma Stretch Parameter Available when Stretch method is Gamalashin. Default is 0.5. Double

Output Result

  • Outputs the panchromatic image data after orthorectification processing into a local folder.
  • Automatically creates an OrthoPanmosaic dataset in the OrthoData datasource based on the panchromatic image data.

Related Topics

Block Adjustment

Multispectral and Panchromatic Registration

Image Fusion