Java java.awt.image Class RGBImageFilter（JDK8）

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Java™ Platform
Standard Ed. 8

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Method

Detail:
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Constr |
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java.lang.Object
- java.awt.image.ImageFilter
- - java.awt.image.RGBImageFilter

All Implemented Interfaces:

ImageConsumer, Cloneable

Direct Known Subclasses:

GrayFilter
```
public abstract class RGBImageFilter
extends ImageFilter
```
This class provides an easy way to create an ImageFilter which modifies the pixels of an image in the default RGB ColorModel. It is meant to be used in conjunction with a FilteredImageSource object to produce filtered versions of existing images. It is an abstract class that provides the calls needed to channel all of the pixel data through a single method which converts pixels one at a time in the default RGB ColorModel regardless of the ColorModel being used by the ImageProducer. The only method which needs to be defined to create a useable image filter is the filterRGB method. Here is an example of a definition of a filter which swaps the red and blue components of an image:
```
      class RedBlueSwapFilter extends RGBImageFilter {
          public RedBlueSwapFilter() {
              // The filter's operation does not depend on the
              // pixel's location, so IndexColorModels can be
              // filtered directly.
              canFilterIndexColorModel = true;
          }

          public int filterRGB(int x, int y, int rgb) {
              return ((rgb & 0xff00ff00)
                      | ((rgb & 0xff0000) >> 16)
                      | ((rgb & 0xff) << 16));
          }
      }

 
```
See Also:

FilteredImageSource, ImageFilter, ColorModel.getRGBdefault()

Field Summary

Fields
Modifier and Type	Field and Description
`protected boolean`	`canFilterIndexColorModel` This boolean indicates whether or not it is acceptable to apply the color filtering of the filterRGB method to the color table entries of an IndexColorModel object in lieu of pixel by pixel filtering.
`protected ColorModel`	`newmodel` The `ColorModel` with which to replace `origmodel` when the user calls `substituteColorModel`.
`protected ColorModel`	`origmodel` The `ColorModel` to be replaced by `newmodel` when the user calls `substituteColorModel`.

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 and Description

RGBImageFilter()

Method Summary

All Methods Instance Methods Abstract Methods Concrete Methods
Modifier and Type	Method and Description
`IndexColorModel`	`filterIndexColorModel(IndexColorModel icm)` Filters an IndexColorModel object by running each entry in its color tables through the filterRGB function that RGBImageFilter subclasses must provide.
`abstract int`	`filterRGB(int x, int y, int rgb)` Subclasses must specify a method to convert a single input pixel in the default RGB ColorModel to a single output pixel.
`void`	`filterRGBPixels(int x, int y, int w, int h, int[] pixels, int off, int scansize)` Filters a buffer of pixels in the default RGB ColorModel by passing them one by one through the filterRGB method.
`void`	`setColorModel(ColorModel model)` If the ColorModel is an IndexColorModel and the subclass has set the canFilterIndexColorModel flag to true, we substitute a filtered version of the color model here and wherever that original ColorModel object appears in the setPixels methods.
`void`	`setPixels(int x, int y, int w, int h, ColorModel model, byte[] pixels, int off, int scansize)` If the ColorModel object is the same one that has already been converted, then simply passes the pixels through with the converted ColorModel.
`void`	`setPixels(int x, int y, int w, int h, ColorModel model, int[] pixels, int off, int scansize)` If the ColorModel object is the same one that has already been converted, then simply passes the pixels through with the converted ColorModel, otherwise converts the buffer of integer pixels to the default RGB ColorModel and passes the converted buffer to the filterRGBPixels method to be converted one by one.
`void`	`substituteColorModel(ColorModel oldcm, ColorModel newcm)` Registers two ColorModel objects for substitution.

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
  - origmodel
```
protected ColorModel origmodel
```
    The ColorModel to be replaced by newmodel when the user calls substituteColorModel.
  - newmodel
```
protected ColorModel newmodel
```
    The ColorModel with which to replace origmodel when the user calls substituteColorModel.
  - canFilterIndexColorModel
```
protected boolean canFilterIndexColorModel
```
    This boolean indicates whether or not it is acceptable to apply the color filtering of the filterRGB method to the color table entries of an IndexColorModel object in lieu of pixel by pixel filtering. Subclasses should set this variable to true in their constructor if their filterRGB method does not depend on the coordinate of the pixel being filtered.
    
    See Also:
    
    substituteColorModel(java.awt.image.ColorModel, java.awt.image.ColorModel), filterRGB(int, int, int), IndexColorModel
- Constructor Detail
  - RGBImageFilter
```
public RGBImageFilter()
```
- Method Detail
  - setColorModel
```
public void setColorModel(ColorModel model)
```
    If the ColorModel is an IndexColorModel and the subclass has set the canFilterIndexColorModel flag to true, we substitute a filtered version of the color model here and wherever that original ColorModel object appears in the setPixels methods. If the ColorModel is not an IndexColorModel or is null, this method overrides the default ColorModel used by the ImageProducer and specifies the default RGB ColorModel instead.
    Note: This method is intended to be called by the ImageProducer of the Image whose pixels are being filtered. Developers using this class to filter pixels from an image should avoid calling this method directly since that operation could interfere with the filtering operation.
    
    Specified by:
    
    setColorModel in interface ImageConsumer
    
    Overrides:
    
    setColorModel in class ImageFilter
    
    Parameters:
    
    model - the specified ColorModel
    
    See Also:
    
    ImageConsumer, ColorModel.getRGBdefault()
  - substituteColorModel
```
public void substituteColorModel(ColorModel oldcm,
                                 ColorModel newcm)
```
    Registers two ColorModel objects for substitution. If the oldcm is encountered during any of the setPixels methods, the newcm is substituted and the pixels passed through untouched (but with the new ColorModel object).
    
    Parameters:
    
    oldcm - the ColorModel object to be replaced on the fly
    
    newcm - the ColorModel object to replace oldcm on the fly
  - filterIndexColorModel
```
public IndexColorModel filterIndexColorModel(IndexColorModel icm)
```
    Filters an IndexColorModel object by running each entry in its color tables through the filterRGB function that RGBImageFilter subclasses must provide. Uses coordinates of -1 to indicate that a color table entry is being filtered rather than an actual pixel value.
    
    Parameters:
    
    icm - the IndexColorModel object to be filtered
    
    Returns:
    
    a new IndexColorModel representing the filtered colors
    
    Throws:
    
    NullPointerException - if icm is null
  - filterRGBPixels
```
public void filterRGBPixels(int x,
                            int y,
                            int w,
                            int h,
                            int[] pixels,
                            int off,
                            int scansize)
```
    Filters a buffer of pixels in the default RGB ColorModel by passing them one by one through the filterRGB method.
    
    Parameters:
    
    x - the X coordinate of the upper-left corner of the region of pixels
    
    y - the Y coordinate of the upper-left corner of the region of pixels
    
    w - the width of the region of pixels
    
    h - the height of the region of pixels
    
    pixels - the array of pixels
    
    off - the offset into the pixels array
    
    scansize - the distance from one row of pixels to the next in the array
    
    See Also:
    
    ColorModel.getRGBdefault(), filterRGB(int, int, int)
  - setPixels
```
public void setPixels(int x,
                      int y,
                      int w,
                      int h,
                      ColorModel model,
                      byte[] pixels,
                      int off,
                      int scansize)
```
    If the ColorModel object is the same one that has already been converted, then simply passes the pixels through with the converted ColorModel. Otherwise converts the buffer of byte pixels to the default RGB ColorModel and passes the converted buffer to the filterRGBPixels method to be converted one by one.
    Note: This method is intended to be called by the ImageProducer of the Image whose pixels are being filtered. Developers using this class to filter pixels from an image should avoid calling this method directly since that operation could interfere with the filtering operation.
    
    Specified by:
    
    setPixels in interface ImageConsumer
    
    Overrides:
    
    setPixels in class ImageFilter
    
    Parameters:
    
    x - the X coordinate of the upper-left corner of the area of pixels to be set
    
    y - the Y coordinate of the upper-left corner of the area of pixels to be set
    
    w - the width of the area of pixels
    
    h - the height of the area of pixels
    
    model - the specified ColorModel
    
    pixels - the array of pixels
    
    off - the offset into the pixels array
    
    scansize - the distance from one row of pixels to the next in the pixels array
    
    See Also:
    
    ColorModel.getRGBdefault(), filterRGBPixels(int, int, int, int, int[], int, int)
  - setPixels
```
public void setPixels(int x,
                      int y,
                      int w,
                      int h,
                      ColorModel model,
                      int[] pixels,
                      int off,
                      int scansize)
```
    If the ColorModel object is the same one that has already been converted, then simply passes the pixels through with the converted ColorModel, otherwise converts the buffer of integer pixels to the default RGB ColorModel and passes the converted buffer to the filterRGBPixels method to be converted one by one. Converts a buffer of integer pixels to the default RGB ColorModel and passes the converted buffer to the filterRGBPixels method.
    Note: This method is intended to be called by the ImageProducer of the Image whose pixels are being filtered. Developers using this class to filter pixels from an image should avoid calling this method directly since that operation could interfere with the filtering operation.
    
    Specified by:
    
    setPixels in interface ImageConsumer
    
    Overrides:
    
    setPixels in class ImageFilter
    
    Parameters:
    
    x - the X coordinate of the upper-left corner of the area of pixels to be set
    
    y - the Y coordinate of the upper-left corner of the area of pixels to be set
    
    w - the width of the area of pixels
    
    h - the height of the area of pixels
    
    model - the specified ColorModel
    
    pixels - the array of pixels
    
    off - the offset into the pixels array
    
    scansize - the distance from one row of pixels to the next in the pixels array
    
    See Also:
    
    ColorModel.getRGBdefault(), filterRGBPixels(int, int, int, int, int[], int, int)
  - filterRGB
```
public abstract int filterRGB(int x,
                              int y,
                              int rgb)
```
    Subclasses must specify a method to convert a single input pixel in the default RGB ColorModel to a single output pixel.
    
    Parameters:
    
    x - the X coordinate of the pixel
    
    y - the Y coordinate of the pixel
    
    rgb - the integer pixel representation in the default RGB color model
    
    Returns:
    
    a filtered pixel in the default RGB color model.
    
    See Also:
    
    ColorModel.getRGBdefault(), filterRGBPixels(int, int, int, int, int[], int, int)

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Java™ Platform
Standard Ed. 8

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Detail:
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Java java.awt.image Class RGBImageFilter（JDK8）

Class RGBImageFilter

Field Summary

Fields inherited from class java.awt.image.ImageFilter

Fields inherited from interface java.awt.image.ImageConsumer

Constructor Summary

Method Summary

Methods inherited from class java.awt.image.ImageFilter

Methods inherited from class java.lang.Object

Field Detail

origmodel

newmodel

canFilterIndexColorModel

Constructor Detail

RGBImageFilter

Method Detail

setColorModel

substituteColorModel

filterIndexColorModel

filterRGBPixels

setPixels

setPixels

filterRGB