True Color Output

Feature Description

True color output refers to the process of utilizing image stretching and image enhancement techniques to improve the display effects of imagery, making its colors closer to the actual ground features. This process also converts the imagery into three-band 8-bit unsigned pixel format for output, facilitating subsequent imagery analysis and visualization.

The true color output results can display surface features with colors closely resembling real-world objects. Therefore, it plays a significant role in urban planning, land use classification, agricultural monitoring, map production and updating, etc.

SuperMap ImageX Pro 11i (2023) version starts to support this feature.

Feature Entry

  • Imagery Tab->DOM Data Production Group->True Color Output.
  • DOM Automated Processing Flow/Ortho Data DOM Automated Processing Process Window->True Color Output Node.

Parameter Description

Parameter Name Description Type
Data Type

Available only when launching from Imagery Tab->DOM Data Production Group->True Color Output.

Selects the source of input image data. Options include Image Files and Mosaic Dataset. Default is Image Files.

 Enum
Image Files

Available only when launching from Imagery Tab->DOM Data Production Group->True Color Output.

When Image Files is selected in Data Type, directly input local path information to automatically acquire all images under this path.

 File
Image Datasource

Available only when launching from Imagery Tab->DOM Data Production Group->True Color Output.

When Mosaic Dataset is selected in Data Type, specifies the datasource containing the image dataset.

 Datasource
Image Data When Mosaic Dataset is selected in Data Type, specifies the image dataset. For workflow production, only displays datasets (non-editable). DatasetMosaic
Red Band Index Specifies the red band. Default is 2. Integer
Green Band Index Specifies the green band. Default is 1. Integer
Blue Band Index Specifies the blue band. Default is 0. Integer
Near-Infrared (NIR) Band Index Specifies the near-infrared band. Default is not set. Required when vegetation enhancement is needed. Integer
Automatically Calculate Truncation Percentage

Specifies whether to use Percent Clip method for image stretching. Unchecked by default.

  • Checked: Automatically calculates truncation percentage based on image brightness and performs percent clip accordingly.
  • Unchecked: Uses maximum/minimum truncation percentage for image stretching.
 Boolean
Minimum Truncation Percentage

Available when Automatically Calculate Truncation Percentage is unchecked.

Sets the minimum truncation percentage for linear stretch. Value range: [0,100]. Default is 0.2.

 Double
Maximum Truncation Percentage

Available when Automatically Calculate Truncation Percentage is unchecked.

Sets the maximum truncation percentage for linear stretch. Value range: [0,100]. Default is 99.8.

 Double
Highlighted White Spot Threshold

Available when Automatically Calculate Truncation Percentage is checked.

During image stretching, if the area of highlighted white spots exceeds the specified threshold, the truncation percentage is considered too large. Otherwise, the percentage can be further increased.

Default value is 20000, unit: m². For images with fewer highlighted areas, increase this parameter to obtain higher contrast.

 Double
Use Gamma Correction

Applies gamma correction for non-linear brightness and contrast adjustment to enhance image details and improve display quality.

Unchecked by default. Check to enable gamma correction and select correction method.

 Boolean
Gamma Correction

Available when Use Gamma Correction is checked. Options: Adaptive (default) and Custom.

  • Adaptive: Automatically adjusts gamma values for RGB bands based on image characteristics.
  • Custom: Manually set gamma values for RGB bands. Default is 1.5 for each (range: 0-10).
    • Gamma=1: No correction applied.
    • Gamma>1: Increases contrast in dark areas (brightens overall image).
    • Gamma<1: Increases contrast in bright areas (darkens overall image).
 GammaCorrectMethod
Vegetation Enhancement

Available when all RGB and NIR band indices are specified.

Enhances display effects of vegetation areas. Unchecked by default.

 Boolean
NDVI Threshold

Available when Vegetation Enhancement is checked.

Determines vegetation areas. Vegetation enhancement activates when NDVI exceeds this threshold. Default: 0.0. NDVI = (NIR - Red)/(NIR + Red).

 Double
Green Band Weight

Available when Vegetation Enhancement is checked.

Sets weight of green band in vegetation enhancement. Range: [0,1]. Default: 0.7. Sum with NIR weight must equal 1.

 Double
Near-Infrared Weight

Available when Vegetation Enhancement is checked.

Sets weight of NIR band in vegetation enhancement. Range: [0,1]. Default: 0.3. Sum with green band weight must equal 1.

 Double
Contrast Enhancement Recommended when image contrast is low or using automatic truncation percentage. Enhances display effects. Checked by default. Boolean
Contrast Limit

Available when Contrast Enhancement is checked.

Determines enhancement intensity. Higher values increase enhancement. Default: 1.5.

 Double
Mask Datasource Specifies datasource containing mask dataset. DataSource
Dataset Empty by default (mask disabled). When set, Imagery Data Processing will avoid dataset bounds. DatasetVector
Output Format

Sets storage type for result images. Options: Not Set, Tiff/GeoTIFF (default), Erdas Image, PCIDSK.

For DOM automated processing flow: Uses Processing Path parameter from Set Image Path (non-editable).

For Ortho data DOM process: Uses Processing Path from Add Orthophoto (non-editable).

 FileType
Compression Method

Sets compression method for output images (only for Tiff/GeoTIFF). Default: NONE.

Follows same processing path rules as Output Format.

 CompressMethod
Export Directory

Specifies storage path for result images.

Follows same processing path rules as Output Format.

 File
Add Results to Map Window

Available only when launching from Imagery Tab->DOM Data Production Group->True Color Output.

Checked by default. Displays results in map window upon successful execution.

 Boolean
Create Image Pyramid Checked by default. Builds pyramids using specified resampling method to improve display performance. Boolean
Resampling Method Available when Create Image Pyramid is checked. Default: Average. See Resampling Method. PyramidResampleType
Asynchronously Create Statistics Checked by default. Creates statistics in background for stretch display. Unchecking will create statistics during tool execution (may take longer). Boolean

Output

  • Exports stretched and enhanced image data to local folders.
  • Automatically creates true color image mosaic dataset in OrthoData datasource.

Related Topics

Image Fusion

Image Color Balancing

Image Mosaic