Image Color Balancing

Instructions for Use

Due to factors such as weather conditions, human factors, and sensor characteristics, acquired remote sensing imagery often suffers from inconsistencies in color and brightness. These issues not only lead to errors during image mosaicking but also cause noticeable color differences on both sides of the seams in the mosaicked image, significantly affecting the visual quality and usability of the entire image.

Image color balancing adjusts the color, brightness, and contrast of the imagery, effectively reducing tonal differences between images. It achieves uniform tones, moderate contrast, and distinct layers while ensuring that ground object colors remain undistorted, significantly improving the overall quality and visual consistency of the imagery.

SuperMap iDesktopX11i(2023) version starts to support this feature.

Figure: Original Image Figure: Color Balancing Template Figure: Color Balance Result

Parameter Description

Parameter Name Parameter Interpretation Parameter Type
Data Type

This parameter is available only when the function is launched from the Imagery tab -> DOM Data Production group -> Image Color Balancing.

Select the source of the input image data. Options include Image Files and Mosaic Dataset. The default is Image Files.
Image Files

This parameter is available only when the function is launched from the Imagery tab -> DOM Data Production group -> Image Color Balancing.

After selecting Image Files in Data Type, you can directly input the local path information, and all images under that path will be automatically retrieved.

 File
Image Data Source

This parameter is available only when the function is launched from the Imagery tab -> DOM Data Production group -> True Color Output.

After selecting Mosaic Dataset in Data Type, specify the data source where the image dataset is located.

 Datasource
Image Data After selecting Mosaic Dataset in Data Type, specify the image dataset. If it is a production workflow, only the dataset is displayed and cannot be edited. DatasetMosaic
Color Balancing Method

Two methods are provided: Template Color Balancing and Adaptive Color Uniformity.

  • Template Color Balancing: Refers to the method of adjusting the color characteristics of the image to be balanced based on a template file.
  • Adaptive Color Uniformity: An adaptive method that combines global and local color consistency processing. It does not require specifying a color balancing template and adaptively processes the image.
Color Balancing Template

Available after selecting Template Color Balancing in Color Balancing Method.

Specify local image files as the template and adjust the color characteristics of the image to be balanced based on this template, ensuring that the colors of the image to be balanced are consistent with or highly similar to the template.

 File
Color Balancing Method

Available after selecting Template Color Balancing in Color Balancing Method. The default is Uniform Light and Color.

  • Uniform Light and Color: Maps the grayscale mean and variance of local images to given grayscale mean and variance values. It is a local image transformation where the grayscale variance and mean at different positions in the image have approximately equal values. This increases the contrast in areas with low contrast and decreases it in areas with high contrast, enhancing subtle grayscale information in the image.
  • Color Mapping Uniform Color: Uses a lower-resolution color balancing template to map the template colors onto the image to be processed, completing image color balancing. This method achieves good color balancing results while improving processing efficiency.
 ColorBalanceMethod
Block Size Default is 1024*1024. Smaller block sizes yield better color balancing results but require more time. BlockSizeOption
Red Band Index Set the red band. Default is 0. Integer
Green Band Index Set the green band. Default is 1. Integer
Blue Band Index Set the blue band. Default is 2. Integer
Brightness Used to adjust the brightness of the result image. The value range is [-100,100], and the default value is 0.0. A larger value results in a brighter image. Double
Contrast Used to adjust the contrast of the result image. The value range is [-100,100], and the default value is 0.0. A larger value results in stronger contrast. Double
Saturation Used to adjust the saturation of the result image. The value range is [-100,100], and the default value is 0.0. A larger value results in stronger saturation. Double
Mask Data Not selected by default. If selected and mask data is set, the system will exclude that area before outputting the image color balancing results. Boolean
Data Source Available after selecting Mask Data. Specify the data source where the mask dataset is located.If executing a production workflow, this parameter is not provided. DataSource
Dataset Available after selecting Mask Data. Specify the mask dataset.If executing a production workflow, the mask data from True Color Output is used by default. DatasetVector
Color Balancing Preview Not selected by default, meaning the image color balance result is not previewed. If this checkbox is selected, the execution will be paused during workflow production or standalone image color balancing, and the image color balancing effect will be output to the preview window based on the Preview Resolution. Boolean
Color Balancing Resolution

Available after selecting Color Balancing Preview.

Set the resolution for color balancing preview. The default is Reduce by 4 times, which is 1/4 of the original image resolution. You can click the Preview button on the right to view the image color balancing effect.

 OrthoRatioDecreaseMethod
Export Directory

Set the storage path for the result image.

If executing a production workflow, use the Processing path parameter from Set Image Path or Add Orthophoto, and this field is not editable.

 File
Resampling Method Set the image resampling method. Options include Nearest, Bilinear, and Cubic. The default is Bilinear. For more information, refer to Resampling Method. ResampleMethod
Result Minimum Value Set the minimum pixel value in the result image. The default is 1. Integer
Result Maximum Value Set the maximum pixel value in the result image. The default is 255. Integer
NoData Value Set the pixel value for no-data areas in the image. The default is 0.0. Double
Resolution Type

Specify the method for outputting the resulting image resolution. The default is Original Resolution.

  • Original Resolution: Retains the original resolution of the input image.
  • Fixed Value: Uses the 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 will pop up. You can click the Add button on the toolbar to add a record. Then click the cell in the Satellite Sensor Type column to select the sensor type. Finally, enter the resolution corresponding to the sensor type in the Resolution column cell.
    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 simultaneously (e.g., ZY3, GF-2, LandSat) but only set the resolution for one satellite sensor type (e.g., only set for ZY3), images from other satellite sensor types (e.g., GF-2 and LandSat) will be output using their original resolution.
 OrthoRatioType
Output Format

Set the storage type for the result image. Options include Not Set, Tiff/GeoTIFF, Erdas Image, and PCIDSK. The default is Tiff/GeoTIFF, which means using the original storage type of the image for output.

If executing a production workflow, use the Output Format parameter from Set Image Path or Add Orthophoto, and this field is not editable.

 FileType
Compression Method

Set the compression method for the output image. Available only when the output format is Tiff/GeoTIFF. The default is NONE.

If executing a production workflow, use the Compression Method parameter from Set Image Path or Add Orthophoto, and this field is not editable.

 CompressMethod
Output as Original Image Coordinate Select this parameter to output the coordinate system of the result data using the image coordinate system of the input data. Otherwise, use the Output Coordinate System parameter from Set Image Path or Add Orthophoto, and this field is not editable. Boolean
Add Results to Map Window

This parameter is available only when the function is launched from the Imagery tab -> DOM Data Production group -> Image Color Balancing.

Selected by default, meaning the result data will be added to the map window for display after successful execution.

 Boolean
Create Image Pyramid Selected by default. Builds pyramids for the image data based on the specified resampling method, improving image zoom display rendering and performance. Boolean
Resampling Method Available after selecting Create Image Pyramid. The default is Average. For more information, refer to Resampling Method. ResamplingMethod
Asynchronously Create Statistics During image browsing, the layer will be stretched based on statistics information. If the image does not have statistics information, it will be displayed using the default stretch method, and 8-bit data will not be stretched. Selected by default, meaning statistics will be created for the image in the background without affecting workflow execution. If deselected, statistics will be created while executing this tool, which may consume time. Boolean

Output Result

  • Output the image data after color balancing processing to the local folder.
  • Automatically create an image color balancing mosaic dataset in the OrthoData data source based on the output image data.

Related Topics

True Color Output

Image Fusion

Image Mosaic