Generate Orthophoto

Feature Description

A Digital Orthophoto Map (DOM), often abbreviated as an orthophoto, is an image dataset generated by vertically projecting aerial or satellite imagery of the Earth's surface. During this vertical projection, the system eliminates geometric distortions caused by factors such as terrain relief and camera tilt, endowing the orthophoto with uniform geometric accuracy. Simultaneously, orthophotos can be seamlessly overlaid with maps, vector data, etc., providing reliable support for precise spatial analysis and measurement. Generating an orthophoto refers to the process of outputting these processed image datasets.

In the process production flow, only panchromatic orthophotos are output by default.

Supported starting from SuperMap iDesktopX 11i(2023) version.

Parameter Description

Parameter Name Parameter Interpretation Parameter Type
Dataset

Displays the original image used for generating the panchromatic orthophoto; it is not editable.

 DatasetMosaic
Export Directory Uses the Processing Path parameter from Set the Image Path; it is not editable. File
Resolution Type

Specifies the method for defining the output resulting image resolution. The default is Original Resolution.

  • Original Resolution: Preserves the original resolution of the input image.
  • Fixed Value: Uses the entered fixed value as the resolution for the output image.
  • Custom: Outputs different resolutions based on different satellite sensor types. Selecting the Custom option will pop up the Custom Resolution: dialog. You can click the Add button on the toolbar to add a new record. Then click the cell in the Satellite Sensor Type column to select a sensor type. Finally, enter the resolution corresponding to the sensor type in the cell of the Resolution column.
    Note:
    • If the corresponding satellite sensor type is not found, please select the USEDEFINE option. When this option is selected, 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 simultaneously (e.g., ZY3, GF-2, LandSat) but only setting the resolution for one sensor type (e.g., only setting for ZY3), then images from 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 from Set the Image Path; it is not editable. PrjCoordSys
Output Format Uses the Output Format parameter from Set the Image Path; it is not editable. FileType
Compression Method Uses the Compression Method parameter from Set the Image Path; it is not editable. CompressMethod
Downscale to 8-bit Unsigned

Specifies whether to convert the image's pixel format to 8-bit unsigned for output.

By default, it is not checked, meaning no pixel format conversion is performed, and the image is output using the original image's pixel format to ensure data precision is lossless.

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

 Boolean
Stretch Method Available after Downscale to 8-bit Unsigned is checked. Default is Percent Clip. Also provides Minimum Maximum, Gaussian, Gamalashin, Histogram Equalization, and Logarithmic Stretch. For more method introductions, please refer to Image Stretching Methods. DesktopImageStretchingType
Minimum Percentage

Available when Stretch Method is Percent Clip. The default value is 1.

 Double
Maximum Percentage Available when Stretch Method is Percent Clip. The default value is 99. Double
Gaussian Standard Deviation Coefficient Available when Stretch Method is Gaussian. The default value is 3. Integer
Gamma Stretch Parameter Available when Stretch Method is Gamalashin. The default value is 0.5. Double

Output Result

  • Outputs the panchromatic image data processed with orthorectification to a local file folder.
  • Automatically creates an OrthoPanmosaic dataset in the OrthoData data source based on the panchromatic image data.

Related Topics

Block Network Adjustment

Multispectral and Panchromatic Registration

Image Fusion