java.awt.image
Class MultiPixelPackedSampleModel

java.lang.Object   
  java.awt.image.SampleModel   
      java.awt.image.MultiPixelPackedSampleModel

public class MultiPixelPackedSampleModel
extends SampleModel   

The MultiPixelPackedSampleModel class represents one-banded images and can pack multiple one-sample pixels into one data element. Pixels are not allowed to span data elements. The data type can be DataBuffer.TYPE_BYTE, DataBuffer.TYPE_USHORT, or DataBuffer.TYPE_INT. Each pixel must be a power of 2 number of bits and a power of 2 number of pixels must fit exactly in one data element. Pixel bit stride is equal to the number of bits per pixel. Scanline stride is in data elements and the last several data elements might be padded with unused pixels. Data bit offset is the offset in bits from the beginning of the DataBuffer to the first pixel and must be a multiple of pixel bit stride.

The following code illustrates extracting the bits for pixel x, y from DataBuffer data and storing the pixel data in data elements of type dataType:

      int dataElementSize = DataBuffer.getDataTypeSize(dataType);
      int bitnum = dataBitOffset + x*pixelBitStride;
      int element = data.getElem(y*scanlineStride + bitnum/dataElementSize);
      int shift = dataElementSize - (bitnum & (dataElementSize-1))
                  - pixelBitStride;
      int pixel = (element >> shift) & ((1 << pixelBitStride) - 1);
 

Field Summary

Fields inherited from class java.awt.image.SampleModel

dataType , height , numBands , width

Constructor Summary

MultiPixelPackedSampleModel (int dataType, int w, int h, int numberOfBits)
Constructs a MultiPixelPackedSampleModel with the specified data type, width, height and number of bits per pixel.

MultiPixelPackedSampleModel (int dataType, int w, int h, int numberOfBits, int scanlineStride, int dataBitOffset)
Constructs a MultiPixelPackedSampleModel with specified data type, width, height, number of bits per pixel, scanline stride and data bit offset.

Method Summary

SampleModel	createCompatibleSampleModel (int w, int h) Creates a new MultiPixelPackedSampleModel with the specified width and height.
DataBuffer	createDataBuffer () Creates a DataBuffer that corresponds to this MultiPixelPackedSampleModel.
SampleModel	createSubsetSampleModel (int[] bands) Creates a new MultiPixelPackedSampleModel with a subset of the bands of this MultiPixelPackedSampleModel.
boolean	equals (Object o) Indicates whether some other object is "equal to" this one.
int	getBitOffset (int x) Returns the offset, in bits, into the data element in which it is stored for the xth pixel of a scanline.
int	getDataBitOffset () Returns the data bit offset in bits.
Object	getDataElements (int x, int y, Object obj, DataBuffer data) Returns data for a single pixel in a primitive array of type TransferType.
int	getNumDataElements () Returns the number of data elements needed to transfer one pixel via the getDataElements(int, int, java.lang.Object, java.awt.image.DataBuffer) and setDataElements(int, int, java.lang.Object, java.awt.image.DataBuffer) methods.
int	getOffset (int x, int y) Returns the offset of pixel (x, y) in data array elements.
int[]	getPixel (int x, int y, int[] iArray, DataBuffer data) Returns the specified single band pixel in the first element of an int array.
int	getPixelBitStride () Returns the pixel bit stride in bits.
int	getSample (int x, int y, int b, DataBuffer data) Returns as int the sample in a specified band for the pixel located at (x, y).
int[]	getSampleSize () Returns the number of bits per sample for all bands.
int	getSampleSize (int band) Returns the number of bits per sample for the specified band.
int	getScanlineStride () Returns the scanline stride.
int	getTransferType () Returns the TransferType used to transfer pixels by way of the getDataElements and setDataElements methods.
int	hashCode () Returns a hash code value for the object.
void	setDataElements (int x, int y, Object obj, DataBuffer data) Sets the data for a single pixel in the specified DataBuffer from a primitive array of type TransferType.
void	setPixel (int x, int y, int[] iArray, DataBuffer data) Sets a pixel in the DataBuffer using an int array for input.
void	setSample (int x, int y, int b, int s, DataBuffer data) Sets a sample in the specified band for the pixel located at (x, y) in the DataBuffer using an int for input.

Methods inherited from class java.awt.image.SampleModel

getDataElements , getDataType , getHeight , getNumBands , getPixel , getPixel , getPixels , getPixels , getPixels , getSampleDouble , getSampleFloat , getSamples , getSamples , getSamples , getWidth , setDataElements , setPixel , setPixel , setPixels , setPixels , setPixels , setSample , setSample , setSamples , setSamples , setSamples

Methods inherited from class java.lang.Object

clone , finalize , getClass , notify , notifyAll , toString , wait , wait , wait

Constructor Detail

MultiPixelPackedSampleModel

public MultiPixelPackedSampleModel(int dataType,
                                   int w,
                                   int h,
                                   int numberOfBits)

Constructs a MultiPixelPackedSampleModel with the specified data type, width, height and number of bits per pixel.

Parameters:

dataType - the data type for storing samples

w - the width, in pixels, of the region of image data described

h - the height, in pixels, of the region of image data described

numberOfBits - the number of bits per pixel

Throws:

IllegalArgumentException - if dataType is not either DataBuffer.TYPE_BYTE, DataBuffer.TYPE_USHORT, or DataBuffer.TYPE_INT

MultiPixelPackedSampleModel

public MultiPixelPackedSampleModel(int dataType,
                                   int w,
                                   int h,
                                   int numberOfBits,
                                   int scanlineStride,
                                   int dataBitOffset)

Constructs a MultiPixelPackedSampleModel with specified data type, width, height, number of bits per pixel, scanline stride and data bit offset.

Parameters:

dataType - the data type for storing samples

w - the width, in pixels, of the region of image data described

h - the height, in pixels, of the region of image data described

numberOfBits - the number of bits per pixel

scanlineStride - the line stride of the image data

dataBitOffset - the data bit offset for the region of image data described

Throws:

RasterFormatException - if the number of bits per pixel is not a power of 2 or if a power of 2 number of pixels do not fit in one data element.

IllegalArgumentException - if w or h is not greater than 0

IllegalArgumentException - if dataType is not either DataBuffer.TYPE_BYTE, DataBuffer.TYPE_USHORT, or DataBuffer.TYPE_INT

Method Detail

createCompatibleSampleModel

public SampleModel    createCompatibleSampleModel(int w,
                                               int h)

Creates a new MultiPixelPackedSampleModel with the specified width and height. The new MultiPixelPackedSampleModel has the same storage data type and number of bits per pixel as this MultiPixelPackedSampleModel.

Specified by:

createCompatibleSampleModel in class SampleModel

Parameters:

w - the specified width

h - the specified height

Returns:

a SampleModel with the specified width and height and with the same storage data type and number of bits per pixel as this MultiPixelPackedSampleModel.

Throws:

IllegalArgumentException - if w or h is not greater than 0

createDataBuffer

public DataBuffer    createDataBuffer()

Creates a DataBuffer that corresponds to this MultiPixelPackedSampleModel. The DataBuffer object's data type and size is consistent with this MultiPixelPackedSampleModel. The DataBuffer has a single bank.

Specified by:

createDataBuffer in class SampleModel

Returns:

a DataBuffer with the same data type and size as this MultiPixelPackedSampleModel.

getNumDataElements

public int getNumDataElements()

Returns the number of data elements needed to transfer one pixel via the getDataElements(int, int, java.lang.Object, java.awt.image.DataBuffer) and setDataElements(int, int, java.lang.Object, java.awt.image.DataBuffer) methods. For a MultiPixelPackedSampleModel, this is one.

Specified by:

getNumDataElements in class SampleModel

Returns:

the number of data elements.

See Also:

SampleModel.getDataElements(int, int, Object, DataBuffer) , SampleModel.getDataElements(int, int, int, int, Object, DataBuffer) , SampleModel.setDataElements(int, int, Object, DataBuffer) , SampleModel.setDataElements(int, int, int, int, Object, DataBuffer) , SampleModel.getTransferType()

getSampleSize

public int[] getSampleSize()

Returns the number of bits per sample for all bands.

Specified by:

getSampleSize in class SampleModel

Returns:

the number of bits per sample.

getSampleSize

public int getSampleSize(int band)

Returns the number of bits per sample for the specified band.

Specified by:

getSampleSize in class SampleModel

Parameters:

band - the specified band

Returns:

the number of bits per sample for the specified band.

getOffset

public int getOffset(int x,
                     int y)

Returns the offset of pixel (x, y) in data array elements.

Parameters:

x, y - the specified pixel

Returns:

the offset of the specified pixel.

getBitOffset

public int getBitOffset(int x)

Returns the offset, in bits, into the data element in which it is stored for the xth pixel of a scanline. This offset is the same for all scanlines.

Parameters:

x - the specified pixel

Returns:

the bit offset of the specified pixel.

getScanlineStride

public int getScanlineStride()

Returns the scanline stride.

Returns:

the scanline stride of this MultiPixelPackedSampleModel.

getPixelBitStride

public int getPixelBitStride()

Returns the pixel bit stride in bits. This value is the same as the number of bits per pixel.

Returns:

the pixelBitStride of this MultiPixelPackedSampleModel.

getDataBitOffset

public int getDataBitOffset()

Returns the data bit offset in bits.

Returns:

the dataBitOffset of this MultiPixelPackedSampleModel.

getTransferType

public int getTransferType()

Returns the TransferType used to transfer pixels by way of the getDataElements and setDataElements methods. The TransferType might or might not be the same as the storage DataType. The TransferType is one of DataBuffer.TYPE_BYTE, DataBuffer.TYPE_USHORT, or DataBuffer.TYPE_INT.

Overrides:

getTransferType in class SampleModel

Returns:

the transfertype.

See Also:

SampleModel.getDataElements(int, int, Object, DataBuffer) , SampleModel.getDataElements(int, int, int, int, Object, DataBuffer) , SampleModel.setDataElements(int, int, Object, DataBuffer) , SampleModel.setDataElements(int, int, int, int, Object, DataBuffer) , SampleModel.getNumDataElements()