Package com.twelvemonkeys.image

Class BrightnessContrastFilter

  • All Implemented Interfaces:
    java.awt.image.ImageConsumer, java.lang.Cloneable
    public class BrightnessContrastFilter
extends java.awt.image.RGBImageFilter
    Adjusts the contrast and brightness of an image.

    For brightness, the valid range is -2.0,..,0.0,..,2.0. A value of 0.0 means no change. Negative values will make the pixels darker. Maximum negative value (-2) will make all filtered pixels black. Positive values will make the pixels brighter. Maximum positive value (2) will make all filtered pixels white.

    For contrast, the valid range is -1.0,..,0.0,..,1.0. A value of 0.0 means no change. Negative values will reduce contrast. Maximum negative value (-1) will make all filtered pixels grey (no contrast). Positive values will increase contrast. Maximum positive value (1) will make all filtered pixels primary colors (either black, white, cyan, magenta, yellow, red, blue or green).

    Version:
    $Id: //depot/branches/personal/haraldk/twelvemonkeys/release-2/twelvemonkeys-core/src/main/java/com/twelvemonkeys/image/BrightnessContrastFilter.java#1 $

    • Field Summary

      Fields 
      Modifier and Type Field Description
      private int[] LUT  

      • Fields inherited from class java.awt.image.RGBImageFilter

        canFilterIndexColorModel, newmodel, origmodel

      • Fields inherited from class java.awt.image.ImageFilter

        consumer

      • Fields inherited from interface java.awt.image.ImageConsumer

        COMPLETESCANLINES, IMAGEABORTED, IMAGEERROR, RANDOMPIXELORDER, SINGLEFRAME, SINGLEFRAMEDONE, SINGLEPASS, STATICIMAGEDONE, TOPDOWNLEFTRIGHT

    • Constructor Summary

      Constructors 
      Constructor Description
      BrightnessContrastFilter()
      Creates a BrightnessContrastFilter with default values (brightness=0.3, contrast=0.3).
      BrightnessContrastFilter​(float pBrightness, float pContrast)
      Creates a BrightnessContrastFilter with the given values for brightness and contrast.

    • Method Summary

      All Methods Static Methods Instance Methods Concrete Methods 
      Modifier and Type Method Description
      private static int clamp​(int i)  
      private static int[] createLUT​(float pBrightness, float pContrast)  
      int filterRGB​(int pX, int pY, int pARGB)
      Filters one pixel, adjusting brightness and contrast according to this filter.

      • Methods inherited from class java.awt.image.RGBImageFilter

        filterIndexColorModel, filterRGBPixels, setColorModel, setPixels, setPixels, substituteColorModel

      • Methods inherited from class java.awt.image.ImageFilter

        clone, getFilterInstance, imageComplete, resendTopDownLeftRight, setDimensions, setHints, setProperties

      • Methods inherited from class java.lang.Object

        equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

    • Field Detail

      • LUT

        private final int[] LUT

    • Constructor Detail

      • BrightnessContrastFilter

        public BrightnessContrastFilter()
        Creates a BrightnessContrastFilter with default values (brightness=0.3, contrast=0.3).

        This will slightly increase both brightness and contrast.

      • BrightnessContrastFilter

        public BrightnessContrastFilter​(float pBrightness,
                                float pContrast)
        Creates a BrightnessContrastFilter with the given values for brightness and contrast.

        For brightness, the valid range is -2.0,..,0.0,..,2.0. A value of 0.0 means no change. Negative values will make the pixels darker. Maximum negative value (-2) will make all filtered pixels black. Positive values will make the pixels brighter. Maximum positive value (2) will make all filtered pixels white.

        For contrast, the valid range is -1.0,..,0.0,..,1.0. A value of 0.0 means no change. Negative values will reduce contrast. Maximum negative value (-1) will make all filtered pixels grey (no contrast). Positive values will increase contrast. Maximum positive value (1) will make all filtered pixels primary colors (either black, white, cyan, magenta, yellow, red, blue or green).

        Parameters:
        pBrightness - adjust the brightness of the image, in the range -2.0,..,0.0,..,2.0.
        pContrast - adjust the contrast of the image, in the range -1.0,..,0.0,..,1.0.

    • Method Detail

      • createLUT

        private static int[] createLUT​(float pBrightness,
                               float pContrast)

      • clamp

        private static int clamp​(int i)

      • filterRGB

        public int filterRGB​(int pX,
                     int pY,
                     int pARGB)
        Filters one pixel, adjusting brightness and contrast according to this filter.
        Specified by:
        filterRGB in class java.awt.image.RGBImageFilter
        Parameters:
        pX - x
        pY - y
        pARGB - pixel value in default color space
        Returns:
        the filtered pixel value in the default color space