Bit Depth Conversion

Instructions for use

Bit depth conversion is used to adjust the bit depth of imagery, such as converting 16-bit unsigned imagery to 8-bit unsigned imagery.

A bit is the smallest unit in computer memory, used to record the color value of each pixel. The more colors an image has, the more bits are required. The number of bits used per pixel in a computer is referred to as bit depth.

SuperMap iDesktopX 2025 Update1 version and later support this feature.

Function Entry

  • Toolbox->Imagery->Basic tools->Bit Depth Conversion.
  • Start tab->Common Imagery Tools group->Bit Depth Conversion.

Parameter description

Parameter Name Parameter Interpretation Parameter Type

Image file list

Use Add Image, Select All, Select Reverse, and Delete functions via the Image file list to manage image files.

  • Add Image: Supports setting the imagery for bit depth conversion through four methods: add file, add folder, add list, and add mosaic dataset.
    • Add File: Select specific image files from a local directory as the images to be processed. Supported formats include *.tiff, *.tif, *.img, and *.pix.
    • Add Folder: Select a folder from a local directory; it will automatically retrieve all images (formats: *.tiff, *.tif, *.img, *.pix) within that folder and its subfolders as the images to be processed.
    • Add List: Select a manifest file (*.csv) from a local directory; it will retrieve the images to be processed based on the image names and path information in the manifest file.
    • Add Mosaic Data: Select a dataset from an open data source in the current workspace as the image to be processed.
  • Select All: Select all records in the list.
  • Select Reverse: Invert the selection of all records in the list.
  • Delete: Delete the selected records from the list.
DatasetImage
Pixel format Set the pixel bit depth for the output channels after processing. Available options include:
  • 8-bit Unsigned: Unsigned 8-bit integer.
  • 16-bit Unsigned: Unsigned 16-bit integer.
  • 16-bit: Signed 16-bit integer.
  • 32-bit: Signed 32-bit integer.
PixelFormat
Stretch method

Set the method for image stretching. Default is Percent Clip. Other options include Gaussian, Gamma, Histogram Equalization, and Logarithmic stretch. For more information on methods, please refer to Image Stretching Methods.

ImageStretchingType
Minimum Value Available when Stretch method is set to Percent Clip. Default value is 1. Double
Maximum Value Available when Stretch method is set to Percent Clip. Default value is 99. Double
Gaussian standard deviation coefficient Available when Stretch method is set to Gaussian. Default value is 3. Integer
Gamma coefficient Available when Stretch method is set to Gamma. Default value is 0.5. Double
NoData Value Set the value for the no-data areas in the image. Default is 0. Double
Index Set the index to be exported, corresponding to the order and band values.
Boolean
Output directory Set the storage path for the result image. String
File type Set the storage type for the result image. Options include Not Set, Tiff/GeoTIFF, Erdas Image, and PCIDSK. Default is Tiff/GeoTIFF. Selecting Not Set means the output will use the original storage type of the image. FileType
Compression method Set the compression method for the output image. Available only when the output format is Tiff/GeoTIFF. Default is NONE. CompressMethod

Output Result

The image data after bit depth conversion processing.

Related Topics

Create Image Pyramid

Image resampling

Image export