Create Histograms Dialog

The raster operation create histograms dialog window allows the user to generate histograms for visually enhancing one or more geospatial image files.

The dialog controls are:

• Files To Process
  
  A list of one or more geospatial imagery files that the user wants to generate a histogram for.
• Remove All
  
  When this button is clicked all the file paths are removed from the list.
• Browse
  
  When this button is clicked a file select dialog is displayed for the user to select one or more geospatial imagery files to be added to the list.
• Approximate
  
  Select this option to generate the histograms using a random sampling of pixel values from the source image(s). This option creates histograms fast and the approximations are generally pretty close to actual results but the quality of the hsitogram can degenerate if the source images contain a lot of transparent areas. When images contain large areas of transparency the random sampling algorithm can break down because it may not sample enough pixels that have actual data and skew the results. When this happens the resulting image(s) may end up being completely black or transparent. To resolve this issue do not select this option and build full histograms. Full histograms use every valid pixel in the image when computing the histogram values but are slower to compute than the approximate method.
• Include Values That Fall Outside Of Range
  
  Select this option to include values that fall outside the range of the data type color space. Sometimes image files contain pixel values that are outside the range of possible color values for the pixel data type. If this option is selected then the color values that fall outside the range will be included in the bucket count that is closest to the pixel value. In other words, pixels that fall below the range will be accumulated into the minimum pixel value count and pixels that fall above the range will be accumulated into the maximum pixel value count. Choosing this option can skew the histogram results so use this option only if you are sure you want to include these values.
• Replace Existing Histograms
  
  Select this option if existing histogram files with the same file names as the source images should be replaced.
• OK
  
  When this button is clicked the dialog queues the Create Histograms task with the Parallel Processing Server and closes the dialog. Use the Task Pane window to monitor the task progress. A popup balloon window and the Task Pane will alert the user when the task is complete.
• Cancel
  
  Closes the dialog window.