File	Doc	Category	Size	Date	Package
MultiPixelPackedSampleModel.java	API Doc	Java SE 5 API	26460	Fri Aug 26 14:56:54 BST 2005	java.awt.image

MultiPixelPackedSampleModel

• java.lang.Object
  • java.awt.image.SampleModel

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);

Fields Summary
int	pixelBitStride The number of bits from one pixel to the next.
int	bitMask Bitmask that extracts the rightmost pixel of a data element.
int	pixelsPerDataElement The number of pixels that fit in a data element. Also used as the number of bits per pixel.
int	dataElementSize The size of a data element in bits.
int	dataBitOffset The bit offset into the data array where the first pixel begins.
int	scanlineStride ScanlineStride of the data buffer described in data array elements.

Constructors Summary
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. param dataType the data type for storing samples param w the width, in pixels, of the region of image data described param h the height, in pixels, of the region of image data described param numberOfBits the number of bits per pixel throws IllegalArgumentException if dataType is not either DataBuffer.TYPE_BYTE, DataBuffer.TYPE_USHORT, or DataBuffer.TYPE_INT this(dataType,w,h, numberOfBits, (w*numberOfBits+DataBuffer.getDataTypeSize(dataType)-1)/ DataBuffer.getDataTypeSize(dataType), 0); if (dataType != DataBuffer.TYPE_BYTE && dataType != DataBuffer.TYPE_USHORT && dataType != DataBuffer.TYPE_INT) { throw new IllegalArgumentException("Unsupported data type "+ dataType); }
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. param dataType the data type for storing samples param w the width, in pixels, of the region of image data described param h the height, in pixels, of the region of image data described param numberOfBits the number of bits per pixel param scanlineStride the line stride of the image data param dataBitOffset the data bit offset for the region of image data described exception 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. throws IllegalArgumentException if w or h is not greater than 0 throws IllegalArgumentException if dataType is not either DataBuffer.TYPE_BYTE, DataBuffer.TYPE_USHORT, or DataBuffer.TYPE_INT super(dataType, w, h, 1); if (dataType != DataBuffer.TYPE_BYTE && dataType != DataBuffer.TYPE_USHORT && dataType != DataBuffer.TYPE_INT) { throw new IllegalArgumentException("Unsupported data type "+ dataType); } this.dataType = dataType; this.pixelBitStride = numberOfBits; this.scanlineStride = scanlineStride; this.dataBitOffset = dataBitOffset; this.dataElementSize = DataBuffer.getDataTypeSize(dataType); this.pixelsPerDataElement = dataElementSize/numberOfBits; if (pixelsPerDataElement*numberOfBits != dataElementSize) { throw new RasterFormatException("MultiPixelPackedSampleModel " + "does not allow pixels to " + "span data element boundaries"); } this.bitMask = (1 << numberOfBits) - 1;

Methods Summary
public java.awt.image.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. param w the specified width param h the specified height return a {@link 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 SampleModel sampleModel = new MultiPixelPackedSampleModel(dataType, w, h, pixelBitStride); return sampleModel;
public java.awt.image.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. return a DataBuffer with the same data type and size as this MultiPixelPackedSampleModel. DataBuffer dataBuffer = null; int size = (int)scanlineStride*height; switch (dataType) { case DataBuffer.TYPE_BYTE: dataBuffer = new DataBufferByte(size+(dataBitOffset+7)/8); break; case DataBuffer.TYPE_USHORT: dataBuffer = new DataBufferUShort(size+(dataBitOffset+15)/16); break; case DataBuffer.TYPE_INT: dataBuffer = new DataBufferInt(size+(dataBitOffset+31)/32); break; } return dataBuffer;
public java.awt.image.SampleModel	createSubsetSampleModel(int[] bands) Creates a new MultiPixelPackedSampleModel with a subset of the bands of this MultiPixelPackedSampleModel. Since a MultiPixelPackedSampleModel only has one band, the bands argument must have a length of one and indicate the zeroth band. param bands the specified bands return a new SampleModel with a subset of bands of this MultiPixelPackedSampleModel. exception RasterFormatException if the number of bands requested is not one. throws IllegalArgumentException if w or h is not greater than 0 if (bands != null) { if (bands.length != 1) throw new RasterFormatException("MultiPixelPackedSampleModel has " + "only one band."); } SampleModel sm = createCompatibleSampleModel(width, height); return sm;
public boolean	equals(java.lang.Object o) if ((o == null) || !(o instanceof MultiPixelPackedSampleModel)) { return false; } MultiPixelPackedSampleModel that = (MultiPixelPackedSampleModel)o; return this.width == that.width && this.height == that.height && this.numBands == that.numBands && this.dataType == that.dataType && this.pixelBitStride == that.pixelBitStride && this.bitMask == that.bitMask && this.pixelsPerDataElement == that.pixelsPerDataElement && this.dataElementSize == that.dataElementSize && this.dataBitOffset == that.dataBitOffset && this.scanlineStride == that.scanlineStride;
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. param x the specified pixel return the bit offset of the specified pixel. return (x*pixelBitStride+dataBitOffset)%dataElementSize;
public int	getDataBitOffset() Returns the data bit offset in bits. return the dataBitOffset of this MultiPixelPackedSampleModel. return dataBitOffset;
public java.lang.Object	getDataElements(int x, int y, java.lang.Object obj, java.awt.image.DataBuffer data) Returns data for a single pixel in a primitive array of type TransferType. For a MultiPixelPackedSampleModel, the array has one element, and the type is the smallest of DataBuffer.TYPE_BYTE, DataBuffer.TYPE_USHORT, or DataBuffer.TYPE_INT that can hold a single pixel. Generally, obj should be passed in as null, so that the Object is created automatically and is the correct primitive data type. The following code illustrates transferring data for one pixel from DataBuffer db1, whose storage layout is described by MultiPixelPackedSampleModel mppsm1, to DataBuffer db2, whose storage layout is described by MultiPixelPackedSampleModel mppsm2. The transfer is generally more efficient than using getPixel or setPixel. MultiPixelPackedSampleModel mppsm1, mppsm2; DataBufferInt db1, db2; mppsm2.setDataElements(x, y, mppsm1.getDataElements(x, y, null, db1), db2); Using getDataElements or setDataElements to transfer between two DataBuffer/SampleModel pairs is legitimate if the SampleModels have the same number of bands, corresponding bands have the same number of bits per sample, and the TransferTypes are the same. If obj is not null, it should be a primitive array of type TransferType. Otherwise, a ClassCastException is thrown. An ArrayIndexOutOfBoundsException is thrown if the coordinates are not in bounds, or if obj is not null and is not large enough to hold the pixel data. param x, y coordinates of the pixel location. param obj a primitive array in which to return the pixel data or null. param data the DataBuffer containing the image data. return an Object containing data for the specified pixel. exception ClassCastException if obj is not a primitive array of type TransferType or is not null exception ArrayIndexOutOfBoundsException if the coordinates are not in bounds, or if obj is not null or not large enough to hold the pixel data see #setDataElements(int, int, Object, DataBuffer) if ((x < 0) || (y < 0) || (x >= width) || (y >= height)) { throw new ArrayIndexOutOfBoundsException ("Coordinate out of bounds!"); } int type = getTransferType(); int bitnum = dataBitOffset + x*pixelBitStride; int shift = dataElementSize - (bitnum & (dataElementSize-1)) - pixelBitStride; int element = 0; switch(type) { case DataBuffer.TYPE_BYTE: byte[] bdata; if (obj == null) bdata = new byte[1]; else bdata = (byte[])obj; element = data.getElem(y*scanlineStride + bitnum/dataElementSize); bdata[0] = (byte)((element >> shift) & bitMask); obj = (Object)bdata; break; case DataBuffer.TYPE_USHORT: short[] sdata; if (obj == null) sdata = new short[1]; else sdata = (short[])obj; element = data.getElem(y*scanlineStride + bitnum/dataElementSize); sdata[0] = (short)((element >> shift) & bitMask); obj = (Object)sdata; break; case DataBuffer.TYPE_INT: int[] idata; if (obj == null) idata = new int[1]; else idata = (int[])obj; element = data.getElem(y*scanlineStride + bitnum/dataElementSize); idata[0] = (element >> shift) & bitMask; obj = (Object)idata; break; } return obj;
public int	getNumDataElements() Returns the number of data elements needed to transfer one pixel via the {@link #getDataElements} and {@link #setDataElements} methods. For a MultiPixelPackedSampleModel, this is one. return the number of data elements. return 1;
public int	getOffset(int x, int y) Returns the offset of pixel (x, y) in data array elements. param x, y the specified pixel return the offset of the specified pixel. int offset = y * scanlineStride; offset += (x*pixelBitStride+dataBitOffset)/dataElementSize; return offset;
public int[]	getPixel(int x, int y, int[] iArray, java.awt.image.DataBuffer data) Returns the specified single band pixel in the first element of an int array. ArrayIndexOutOfBoundsException is thrown if the coordinates are not in bounds. param x, y the coordinates of the pixel location param iArray the array containing the pixel to be returned or null param data the DataBuffer where image data is stored return an array containing the specified pixel. exception ArrayIndexOutOfBoundsException if the coordinates are not in bounds see #setPixel(int, int, int[], DataBuffer) if ((x < 0) || (y < 0) || (x >= width) || (y >= height)) { throw new ArrayIndexOutOfBoundsException ("Coordinate out of bounds!"); } int pixels[]; if (iArray != null) { pixels = iArray; } else { pixels = new int [numBands]; } int bitnum = dataBitOffset + x*pixelBitStride; int element = data.getElem(y*scanlineStride + bitnum/dataElementSize); int shift = dataElementSize - (bitnum & (dataElementSize-1)) - pixelBitStride; pixels[0] = (element >> shift) & bitMask; return pixels;
public int	getPixelBitStride() Returns the pixel bit stride in bits. This value is the same as the number of bits per pixel. return the pixelBitStride of this MultiPixelPackedSampleModel. return pixelBitStride;
public int	getSample(int x, int y, int b, java.awt.image.DataBuffer data) Returns as int the sample in a specified band for the pixel located at (x, y). An ArrayIndexOutOfBoundsException is thrown if the coordinates are not in bounds. param x, y the coordinates of the specified pixel param b the band to return, which is assumed to be 0 param data the DataBuffer containing the image data return the specified band containing the sample of the specified pixel. exception ArrayIndexOutOfBoundException if the specified coordinates are not in bounds. see #setSample(int, int, int, int, DataBuffer) // 'b' must be 0 if ((x < 0) || (y < 0) || (x >= width) || (y >= height) || (b != 0)) { throw new ArrayIndexOutOfBoundsException ("Coordinate out of bounds!"); } int bitnum = dataBitOffset + x*pixelBitStride; int element = data.getElem(y*scanlineStride + bitnum/dataElementSize); int shift = dataElementSize - (bitnum & (dataElementSize-1)) - pixelBitStride; return (element >> shift) & bitMask;
public int[]	getSampleSize() Returns the number of bits per sample for all bands. return the number of bits per sample. int sampleSize[] = {pixelBitStride}; return sampleSize;
public int	getSampleSize(int band) Returns the number of bits per sample for the specified band. param band the specified band return the number of bits per sample for the specified band. return pixelBitStride;
public int	getScanlineStride() Returns the scanline stride. return the scanline stride of this MultiPixelPackedSampleModel. return scanlineStride;
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. return the transfertype. if (pixelBitStride > 16) return DataBuffer.TYPE_INT; else if (pixelBitStride > 8) return DataBuffer.TYPE_USHORT; else return DataBuffer.TYPE_BYTE;
public int	hashCode() int hash = 0; hash = width; hash <<= 8; hash ^= height; hash <<= 8; hash ^= numBands; hash <<= 8; hash ^= dataType; hash <<= 8; hash ^= pixelBitStride; hash <<= 8; hash ^= bitMask; hash <<= 8; hash ^= pixelsPerDataElement; hash <<= 8; hash ^= dataElementSize; hash <<= 8; hash ^= dataBitOffset; hash <<= 8; hash ^= scanlineStride; return hash;
public void	setDataElements(int x, int y, java.lang.Object obj, java.awt.image.DataBuffer data) Sets the data for a single pixel in the specified DataBuffer from a primitive array of type TransferType. For a MultiPixelPackedSampleModel, only the first element of the array holds valid data, and the type must be the smallest of DataBuffer.TYPE_BYTE, DataBuffer.TYPE_USHORT, or DataBuffer.TYPE_INT that can hold a single pixel. The following code illustrates transferring data for one pixel from DataBuffer db1, whose storage layout is described by MultiPixelPackedSampleModel mppsm1, to DataBuffer db2, whose storage layout is described by MultiPixelPackedSampleModel mppsm2. The transfer is generally more efficient than using getPixel or setPixel. MultiPixelPackedSampleModel mppsm1, mppsm2; DataBufferInt db1, db2; mppsm2.setDataElements(x, y, mppsm1.getDataElements(x, y, null, db1), db2); Using getDataElements or setDataElements to transfer between two DataBuffer/SampleModel pairs is legitimate if the SampleModel objects have the same number of bands, corresponding bands have the same number of bits per sample, and the TransferTypes are the same. obj must be a primitive array of type TransferType. Otherwise, a ClassCastException is thrown. An ArrayIndexOutOfBoundsException is thrown if the coordinates are not in bounds, or if obj is not large enough to hold the pixel data. param x, y the coordinates of the pixel location param obj a primitive array containing pixel data param data the DataBuffer containing the image data see #getDataElements(int, int, Object, DataBuffer) if ((x < 0) || (y < 0) || (x >= width) || (y >= height)) { throw new ArrayIndexOutOfBoundsException ("Coordinate out of bounds!"); } int type = getTransferType(); int bitnum = dataBitOffset + x * pixelBitStride; int index = y * scanlineStride + (bitnum / dataElementSize); int shift = dataElementSize - (bitnum & (dataElementSize-1)) - pixelBitStride; int element = data.getElem(index); element &= ~(bitMask << shift); switch(type) { case DataBuffer.TYPE_BYTE: byte[] barray = (byte[])obj; element |= ( ((int)(barray[0])&0xff) & bitMask) << shift; data.setElem(index, element); break; case DataBuffer.TYPE_USHORT: short[] sarray = (short[])obj; element |= ( ((int)(sarray[0])&0xffff) & bitMask) << shift; data.setElem(index, element); break; case DataBuffer.TYPE_INT: int[] iarray = (int[])obj; element |= (iarray[0] & bitMask) << shift; data.setElem(index, element); break; }
public void	setPixel(int x, int y, int[] iArray, java.awt.image.DataBuffer data) Sets a pixel in the DataBuffer using an int array for input. ArrayIndexOutOfBoundsException is thrown if the coordinates are not in bounds. param x, y the coordinates of the pixel location param iArray the input pixel in an int array param data the DataBuffer containing the image data see #getPixel(int, int, int[], DataBuffer) if ((x < 0) || (y < 0) || (x >= width) || (y >= height)) { throw new ArrayIndexOutOfBoundsException ("Coordinate out of bounds!"); } int bitnum = dataBitOffset + x * pixelBitStride; int index = y * scanlineStride + (bitnum / dataElementSize); int shift = dataElementSize - (bitnum & (dataElementSize-1)) - pixelBitStride; int element = data.getElem(index); element &= ~(bitMask << shift); element |= (iArray[0] & bitMask) << shift; data.setElem(index,element);
public void	setSample(int x, int y, int b, int s, java.awt.image.DataBuffer data) Sets a sample in the specified band for the pixel located at (x, y) in the DataBuffer using an int for input. An ArrayIndexOutOfBoundsException is thrown if the coordinates are not in bounds. param x, y the coordinates of the specified pixel param b the band to return, which is assumed to be 0 param s the input sample as an int param data the DataBuffer where image data is stored exception ArrayIndexOutOfBoundsException if the coordinates are not in bounds. see #getSample(int, int, int, DataBuffer) // 'b' must be 0 if ((x < 0) || (y < 0) || (x >= width) || (y >= height) || (b != 0)) { throw new ArrayIndexOutOfBoundsException ("Coordinate out of bounds!"); } int bitnum = dataBitOffset + x * pixelBitStride; int index = y * scanlineStride + (bitnum / dataElementSize); int shift = dataElementSize - (bitnum & (dataElementSize-1)) - pixelBitStride; int element = data.getElem(index); element &= ~(bitMask << shift); element |= (s & bitMask) << shift; data.setElem(index,element);