Histogram Viewer

Version

The current version is Histogram Viewer 2.0.2 (21. June 2010).

Description

The Histogram Viewer generates the histogram of a selected image. When the user right clicks on an image, the option "Show Histogram of Image" is shown in the context menu. If the user selects this option a new window is opened which shows the histogram of the image.

By default the histogram is generated based on the sum of all 3 RGB color channels. Additionally the histogram for each of the 3 color channels can be shown. Some statistics about the histogram are also shown.

Features

  • Grayscale histogram
  • Option to select the way the grayscale histogram is calculated
    • all color channels have the same weight
    • the color channels are weighted according to the human perception (gray = 0.299*red + 0.587*green + 0.114*blue)
  • shows histograms for each color channel
  • shows statistics about the histogram: min, max, mean, median
  • optional hiding of the statistics
  • optional support for multiple histogram windows besides each other
  • shows the individual value and its number of occurrences, when the user moves the mouse over the histogram

Download

The addon can be downloaded via addons.mozilla.org.

Screenshots

The "Show Histogram of Image" option in the context menu
The "Show Histogram of Image" option in the context menu
The Histogram Window with the generated histogram
The Histogram Window with the generated histogram
The Histogram Window showing the histogram of the blue channel
The Histogram Window showing the histogram of the blue channel
The Preferences Window of the Histogram Viewer
The Preferences Window of the Histogram Viewer

Version History

Version 1.0

4. September 2008
  • initial version
  • show histogram of an image after right clicking on that image and selection the "Show Histogram" option

Version 1.1

12. November 2008
  • compatible with Firefox 3.5(please note that it does not work with early beta versions of 3.1/3.5)
  • bug fix for slow loading images
  • histogram window refreshes when new histogram is generated and old window is still open
  • coordinates of window are stored during the session and new histogram windows are placed at the same position

Version 1.2

11. December 2009
  • Mac OS X Bug fixed
  • Support for background images
  • Code CleanUp

Version 2.0

30. April 2010
  • Histogram for individual color channels
  • Statistics
  • Shows current value when hovering with the mouse over the histogram
  • Preferences window
  • optional switching of gray calculation
  • optional support for multiple histogram windows
  • German localization
  • Code refactoring

Version 2.0.1

5. May 2010
  • Min and Max Values in the GUI were mixed. Fixed that. Thanks Alex for pointing that out.

Version 2.0.2

21. June 2010
  • Rounding error in gray calculation fixed. Thanks Jacob for pointing that out.

ideas for future versions

  • show histograms of all color channels in one histogram