## org.apache.batik.ext.awt.image.codec
Class PNGEncodeParam.Gray

    java.lang.Object
      org.apache.batik.ext.awt.image.codec.PNGEncodeParam
          org.apache.batik.ext.awt.image.codec.PNGEncodeParam.Gray

All Implemented Interfaces:
  java.lang.Cloneable, ImageDecodeParam, ImageEncodeParam, java.io.Serializable

Enclosing class:
  PNGEncodeParam

public static class PNGEncodeParam.Gray
extends PNGEncodeParam

See Also:
  Serialized Form

Nested Class Summary

Nested classes inherited from class org.apache.batik.ext.awt.image.codec.PNGEncodeParam
`PNGEncodeParam.Gray, PNGEncodeParam.Palette, PNGEncodeParam.RGB`

Field Summary

Fields inherited from class org.apache.batik.ext.awt.image.codec.PNGEncodeParam
`bitDepth, bitDepthSet, INTENT_ABSOLUTE, INTENT_PERCEPTUAL, INTENT_RELATIVE, INTENT_SATURATION, PNG_FILTER_AVERAGE, PNG_FILTER_NONE, PNG_FILTER_PAETH, PNG_FILTER_SUB, PNG_FILTER_UP`

Constructor Summary
`PNGEncodeParam.Gray()` Constructs an instance of `PNGEncodeParam.Gray`.

Method Summary
`int` `getBackgroundGray()` Returns the suggested gray level of the background.
`int` `getBitShift()` Returns the desired bit shift for a grayscale image.
`int` `getTransparentGray()` Returns the gray value to be used to denote transparency.
`boolean` `isBackgroundSet()` Returns true if a 'bKGD' chunk will be output.
`boolean` `isBitDepthSet()` Returns true if the bit depth has been set.
`boolean` `isBitShiftSet()` Returns true if the bit shift has been set.
`void` `setBackgroundGray(int gray)` Sets the suggested gray level of the background.
`void` `setBitDepth(int bitDepth)` Sets the desired bit depth for a grayscale image.
`void` `setBitShift(int bitShift)` Sets the desired bit shift for a grayscale image.
`void` `setTransparentGray(int transparentGray)` Sets the gray value to be used to denote transparency.
`void` `unsetBackground()` Suppresses the 'bKGD' chunk from being output.
`void` `unsetBitShift()` Suppresses the setting of the bit shift of a grayscale image.

Methods inherited from class org.apache.batik.ext.awt.image.codec.PNGEncodeParam

`addPrivateChunk, filterRow, getBitDepth, getChromaticity, getCompressedText, getDefaultEncodeParam, getGamma, getICCProfileData, getInterlacing, getModificationTime, getNumPrivateChunks, getPaletteHistogram, getPhysicalDimension, getPrivateChunkData, getPrivateChunkType, getSignificantBits, getSRGBIntent, getSuggestedPalette, getText, isChromaticitySet, isCompressedTextSet, isGammaSet, isICCProfileDataSet, isModificationTimeSet, isPaletteHistogramSet, isPhysicalDimensionSet, isSignificantBitsSet, isSRGBIntentSet, isSuggestedPaletteSet, isTextSet, isTransparencySet, paethPredictor, removeAllPrivateChunks, removeUnsafeToCopyPrivateChunks, setChromaticity, setChromaticity, setCompressedText, setGamma, setICCProfileData, setInterlacing, setModificationTime, setPaletteHistogram, setPhysicalDimension, setPhysicalDimension, setSignificantBits, setSRGBIntent, setSuggestedPalette, setText, unsetBitDepth, unsetChromaticity, unsetCompressedText, unsetGamma, unsetICCProfileData, unsetModificationTime, unsetPaletteHistogram, unsetPhysicalDimension, unsetSignificantBits, unsetSRGBIntent, unsetSuggestedPalette, unsetText, unsetTransparency`

Methods inherited from class java.lang.Object
`clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait`

Constructor Detail

### PNGEncodeParam.Gray

    public PNGEncodeParam.Gray()

  Constructs an instance of `PNGEncodeParam.Gray`.

Method Detail

### unsetBackground

    public void unsetBackground()

  Suppresses the 'bKGD' chunk from being output.

  Overrides:
    `unsetBackground` in class `PNGEncodeParam`

### isBackgroundSet

    public boolean isBackgroundSet()

  Returns true if a 'bKGD' chunk will be output.

  Overrides:
    `isBackgroundSet` in class `PNGEncodeParam`

### setBitDepth

    public void setBitDepth(int bitDepth)

  Sets the desired bit depth for a grayscale image. The bit depth must be one of 1, 2, 4, 8, or 16.

  When encoding a source image of a greater bit depth, pixel values will be clamped to the smaller range after shifting by the value given by `getBitShift()`. When encoding a source image of a smaller bit depth, pixel values will be shifted and left-filled with zeroes.

  Specified by:
    `setBitDepth` in class `PNGEncodeParam`

### setBackgroundGray

    public void setBackgroundGray(int gray)

  Sets the suggested gray level of the background.

  The 'bKGD' chunk will encode this information.

### getBackgroundGray

    public int getBackgroundGray()

  Returns the suggested gray level of the background.

  If the background gray level has not previously been set, or has been unset, an `IllegalStateException` will be thrown.

  Throws:
    `java.lang.IllegalStateException` - if the background gray level is not set.

### setTransparentGray

    public void setTransparentGray(int transparentGray)

  Sets the gray value to be used to denote transparency.

  Setting this attribute will cause the alpha channel of the input image to be ignored.

  The 'tRNS' chunk will encode this information.

### getTransparentGray

    public int getTransparentGray()

  Returns the gray value to be used to denote transparency.

  If the transparent gray value has not previously been set, or has been unset, an `IllegalStateException` will be thrown.

  Throws:
    `java.lang.IllegalStateException` - if the transparent gray value is not set.

### setBitShift

    public void setBitShift(int bitShift)

  Sets the desired bit shift for a grayscale image. Pixels in the source image will be shifted right by the given amount prior to being clamped to the maximum value given by the encoded image's bit depth.

### getBitShift

    public int getBitShift()

  Returns the desired bit shift for a grayscale image.

  If the bit shift has not previously been set, or has been unset, an `IllegalStateException` will be thrown.

  Throws:
    `java.lang.IllegalStateException` - if the bit shift is not set.

### unsetBitShift

    public void unsetBitShift()

  Suppresses the setting of the bit shift of a grayscale image. Pixels in the source image will not be shifted prior to encoding.

### isBitShiftSet

    public boolean isBitShiftSet()

  Returns true if the bit shift has been set.

### isBitDepthSet

    public boolean isBitDepthSet()

  Returns true if the bit depth has been set.

Copyright © 2004 Apache Software Foundation. All Rights Reserved.