Images in homogeneous areas may display vertical striping artifacts where pixel brightness varies relative to other nearby pixels. The striping artifacts make images difficult to visualize, and they may negatively impact image processing algorithms.

The SPEAR Vertical Stripe Removal tool is best used when the image background is relatively homogenous (consistent brightness level throughout image). Because it can cause artifacts, using this tool on heterogeneous images (like coastal images containing bright land and dark water) is not recommended.

  1. From the Toolbox, select SPEAR > SPEAR Vertical Stripe Removal. The Vertical Stripe Removal Wizard displays the File Selection panel.
  2. Click Select Input File, choose a multispectral or thermal-infrared file, then click OK.
  3. To optionally process only a portion of the scene, click Select Subset. A small Select Spatial Subset dialog appears.
  4. Click Spatial Subset. The standard Select Spatial Subset dialog appears. When finished, click OK to return to the File Selection panel.
  5. By default, output files are saved to the same directory and use the same rootname as the input file, minus any extension. Output files are appended with a unique suffix. To change the directory and/or root filename, click Select Output Root Name.
  6. Click Next. The Create Mask dialog appears.
  7. Apply an optional mask to the data by clicking Input Band and selecting the desired mask image.

    The darkest and brightest 5% of the image will be masked by default. Dark pixels are displayed as blue, and bright pixels as red. Modify the red and blue percentages to include more or fewer pixels in the mask.

    Right-click on the red or blue color boxes to change the colors used to represent the dark and bright pixels. To remove the highlighted pixels from the display, disable the Show check boxes. The highlighted pixels will not be displayed, but will be available for statistical calculations.

  8. Click Next. The Examine Results dialog appears.

    The original image and the image with vertical striping removed are opened in the display and are dynamically linked for comparison. Use Auto-Flicker to examine your results.

  9. When you are finished examining your results, click Next in the Examine Results panel, then click Finish to exit the Wizard.