| /* Copyright (C) 2004, 2006, Free Software Foundation |
| |
| This file is part of GNU Classpath. |
| |
| GNU Classpath is free software; you can redistribute it and/or modify |
| it under the terms of the GNU General Public License as published by |
| the Free Software Foundation; either version 2, or (at your option) |
| any later version. |
| |
| GNU Classpath is distributed in the hope that it will be useful, but |
| WITHOUT ANY WARRANTY; without even the implied warranty of |
| MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| General Public License for more details. |
| |
| You should have received a copy of the GNU General Public License |
| along with GNU Classpath; see the file COPYING. If not, write to the |
| Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA |
| 02110-1301 USA. |
| |
| Linking this library statically or dynamically with other modules is |
| making a combined work based on this library. Thus, the terms and |
| conditions of the GNU General Public License cover the whole |
| combination. |
| |
| As a special exception, the copyright holders of this library give you |
| permission to link this library with independent modules to produce an |
| executable, regardless of the license terms of these independent |
| modules, and to copy and distribute the resulting executable under |
| terms of your choice, provided that you also meet, for each linked |
| independent module, the terms and conditions of the license of that |
| module. An independent module is a module which is not derived from |
| or based on this library. If you modify this library, you may extend |
| this exception to your version of the library, but you are not |
| obligated to do so. If you do not wish to do so, delete this |
| exception statement from your version. */ |
| |
| package java.awt.image; |
| |
| import gnu.java.awt.Buffers; |
| |
| /** |
| * MultiPixelPackedSampleModel provides a single band model that supports |
| * multiple pixels in a single unit. Pixels have 2^n bits and 2^k pixels fit |
| * per data element. |
| * |
| * @author Jerry Quinn (jlquinn@optonline.net) |
| */ |
| public class MultiPixelPackedSampleModel extends SampleModel |
| { |
| private int scanlineStride; |
| private int[] bitMasks; |
| private int[] bitOffsets; |
| private int[] sampleSize; |
| private int dataBitOffset; |
| private int elemBits; |
| private int numberOfBits; |
| private int numElems; |
| |
| /** |
| * Creates a new <code>MultiPixelPackedSampleModel</code> with the specified |
| * data type, which should be one of: |
| * <ul> |
| * <li>{@link DataBuffer#TYPE_BYTE};</li> |
| * <li>{@link DataBuffer#TYPE_USHORT};</li> |
| * <li>{@link DataBuffer#TYPE_INT};</li> |
| * </ul> |
| * |
| * @param dataType the data type. |
| * @param w the width (in pixels). |
| * @param h the height (in pixels). |
| * @param numberOfBits the number of bits per pixel (must be a power of 2). |
| */ |
| public MultiPixelPackedSampleModel(int dataType, int w, int h, |
| int numberOfBits) |
| { |
| this(dataType, w, h, numberOfBits, 0, 0); |
| } |
| |
| /** |
| * Creates a new <code>MultiPixelPackedSampleModel</code> with the specified |
| * data type, which should be one of: |
| * <ul> |
| * <li>{@link DataBuffer#TYPE_BYTE};</li> |
| * <li>{@link DataBuffer#TYPE_USHORT};</li> |
| * <li>{@link DataBuffer#TYPE_INT};</li> |
| * </ul> |
| * |
| * @param dataType the data type. |
| * @param w the width (in pixels). |
| * @param h the height (in pixels). |
| * @param numberOfBits the number of bits per pixel (must be a power of 2). |
| * @param scanlineStride the number of data elements from a pixel on one |
| * row to the corresponding pixel in the next row. |
| * @param dataBitOffset the offset to the first data bit. |
| */ |
| public MultiPixelPackedSampleModel(int dataType, int w, int h, |
| int numberOfBits, int scanlineStride, |
| int dataBitOffset) |
| { |
| super(dataType, w, h, 1); |
| |
| switch (dataType) |
| { |
| case DataBuffer.TYPE_BYTE: |
| elemBits = 8; |
| break; |
| case DataBuffer.TYPE_USHORT: |
| elemBits = 16; |
| break; |
| case DataBuffer.TYPE_INT: |
| elemBits = 32; |
| break; |
| default: |
| throw new IllegalArgumentException("MultiPixelPackedSampleModel" |
| + " unsupported dataType"); |
| } |
| |
| this.dataBitOffset = dataBitOffset; |
| |
| this.numberOfBits = numberOfBits; |
| if (numberOfBits > elemBits) |
| throw new RasterFormatException("MultiPixelPackedSampleModel pixel size" |
| + " larger than dataType"); |
| switch (numberOfBits) |
| { |
| case 1: case 2: case 4: case 8: case 16: case 32: break; |
| default: |
| throw new RasterFormatException("MultiPixelPackedSampleModel pixel" |
| + " size not 2^n bits"); |
| } |
| numElems = elemBits / numberOfBits; |
| |
| // Compute scan line large enough for w pixels. |
| if (scanlineStride == 0) |
| scanlineStride = ((dataBitOffset + w * numberOfBits) - 1) / elemBits + 1; |
| this.scanlineStride = scanlineStride; |
| |
| |
| sampleSize = new int[1]; |
| sampleSize[0] = numberOfBits; |
| |
| bitMasks = new int[numElems]; |
| bitOffsets = new int[numElems]; |
| for (int i=0; i < numElems; i++) |
| { |
| bitOffsets[numElems - i- 1] = numberOfBits * i; |
| bitMasks[numElems - i - 1] = ((1 << numberOfBits) - 1) << |
| bitOffsets[numElems - i - 1]; |
| } |
| } |
| |
| /** |
| * Creates a new <code>MultiPixelPackedSample</code> model with the same |
| * data type and bits per pixel as this model, but with the specified |
| * dimensions. |
| * |
| * @param w the width (in pixels). |
| * @param h the height (in pixels). |
| * |
| * @return The new sample model. |
| */ |
| public SampleModel createCompatibleSampleModel(int w, int h) |
| { |
| /* FIXME: We can avoid recalculation of bit offsets and sample |
| sizes here by passing these from the current instance to a |
| special private constructor. */ |
| return new MultiPixelPackedSampleModel(dataType, w, h, numberOfBits); |
| } |
| |
| /** |
| * Creates a DataBuffer for holding pixel data in the format and |
| * layout described by this SampleModel. The returned buffer will |
| * consist of one single bank. |
| * |
| * @return A new data buffer. |
| */ |
| public DataBuffer createDataBuffer() |
| { |
| int size = scanlineStride * height; |
| if (dataBitOffset > 0) |
| size += (dataBitOffset - 1) / elemBits + 1; |
| return Buffers.createBuffer(getDataType(), size); |
| } |
| |
| /** |
| * Returns the number of data elements required to transfer a pixel in the |
| * get/setDataElements() methods. |
| * |
| * @return <code>1</code>. |
| */ |
| public int getNumDataElements() |
| { |
| return 1; |
| } |
| |
| /** |
| * Returns an array containing the size (in bits) of the samples in each |
| * band. The <code>MultiPixelPackedSampleModel</code> class supports only |
| * one band, so this method returns an array with length <code>1</code>. |
| * |
| * @return An array containing the size (in bits) of the samples in band zero. |
| * |
| * @see #getSampleSize(int) |
| */ |
| public int[] getSampleSize() |
| { |
| return (int[]) sampleSize.clone(); |
| } |
| |
| /** |
| * Returns the size of the samples in the specified band. Note that the |
| * <code>MultiPixelPackedSampleModel</code> supports only one band -- this |
| * method ignored the <code>band</code> argument, and always returns the size |
| * of band zero. |
| * |
| * @param band the band (this parameter is ignored). |
| * |
| * @return The size of the samples in band zero. |
| * |
| * @see #getSampleSize() |
| */ |
| public int getSampleSize(int band) |
| { |
| return sampleSize[0]; |
| } |
| |
| /** |
| * Returns the index in the data buffer that stores the pixel at (x, y). |
| * |
| * @param x the x-coordinate. |
| * @param y the y-coordinate. |
| * |
| * @return The index in the data buffer that stores the pixel at (x, y). |
| * |
| * @see #getBitOffset(int) |
| */ |
| public int getOffset(int x, int y) |
| { |
| return scanlineStride * y + ((dataBitOffset + x * numberOfBits) / elemBits); |
| } |
| |
| /** |
| * The bit offset (within an element in the data buffer) of the pixels with |
| * the specified x-coordinate. |
| * |
| * @param x the x-coordinate. |
| * |
| * @return The bit offset. |
| */ |
| public int getBitOffset(int x) |
| { |
| return (dataBitOffset + x * numberOfBits) % elemBits; |
| } |
| |
| /** |
| * Returns the offset to the first data bit. |
| * |
| * @return The offset to the first data bit. |
| */ |
| public int getDataBitOffset() |
| { |
| return dataBitOffset; |
| } |
| |
| /** |
| * Returns the number of data elements from a pixel in one row to the |
| * corresponding pixel in the next row. |
| * |
| * @return The scanline stride. |
| */ |
| public int getScanlineStride() |
| { |
| return scanlineStride; |
| } |
| |
| /** |
| * Returns the number of bits per pixel. |
| * |
| * @return The number of bits per pixel. |
| */ |
| public int getPixelBitStride() |
| { |
| return numberOfBits; |
| } |
| |
| /** |
| * Returns the transfer type, which is one of the following (depending on |
| * the number of bits per sample for this model): |
| * <ul> |
| * <li>{@link DataBuffer#TYPE_BYTE};</li> |
| * <li>{@link DataBuffer#TYPE_USHORT};</li> |
| * <li>{@link DataBuffer#TYPE_INT};</li> |
| * </ul> |
| * |
| * @return The transfer type. |
| */ |
| public int getTransferType() |
| { |
| if (numberOfBits <= DataBuffer.getDataTypeSize(DataBuffer.TYPE_BYTE)) |
| return DataBuffer.TYPE_BYTE; |
| else if (numberOfBits <= DataBuffer.getDataTypeSize(DataBuffer.TYPE_USHORT)) |
| return DataBuffer.TYPE_USHORT; |
| return DataBuffer.TYPE_INT; |
| } |
| |
| /** |
| * Normally this method returns a sample model for accessing a subset of |
| * bands of image data, but since <code>MultiPixelPackedSampleModel</code> |
| * only supports a single band, this overridden implementation just returns |
| * a new instance of <code>MultiPixelPackedSampleModel</code>, with the same |
| * attributes as this instance. |
| * |
| * @param bands the bands to include in the subset (this is ignored, except |
| * that if it is non-<code>null</code> a check is made to ensure that the |
| * array length is equal to <code>1</code>). |
| * |
| * @throws RasterFormatException if <code>bands</code> is not |
| * <code>null</code> and <code>bands.length != 1</code>. |
| */ |
| public SampleModel createSubsetSampleModel(int[] bands) |
| { |
| if (bands != null && bands.length != 1) |
| throw new RasterFormatException("MultiPixelPackedSampleModel only" |
| + " supports one band"); |
| return new MultiPixelPackedSampleModel(dataType, width, height, |
| numberOfBits, scanlineStride, dataBitOffset); |
| } |
| |
| /** |
| * Extract one pixel and return in an array of transfer type. |
| * |
| * Extracts the pixel at x, y from data and stores into the 0th index of the |
| * array obj, since there is only one band. If obj is null, a new array of |
| * getTransferType() is created. |
| * |
| * @param x The x-coordinate of the pixel rectangle to store in |
| * <code>obj</code>. |
| * @param y The y-coordinate of the pixel rectangle to store in |
| * <code>obj</code>. |
| * @param obj The primitive array to store the pixels into or null to force |
| * creation. |
| * @param data The DataBuffer that is the source of the pixel data. |
| * @return The primitive array containing the pixel data. |
| * @see java.awt.image.SampleModel#getDataElements(int, int, Object, |
| * DataBuffer) |
| */ |
| public Object getDataElements(int x, int y, Object obj, DataBuffer data) |
| { |
| int pixel = getSample(x, y, 0, data); |
| switch (getTransferType()) |
| { |
| case DataBuffer.TYPE_BYTE: |
| if (obj == null) |
| obj = new byte[1]; |
| ((byte[]) obj)[0] = (byte) pixel; |
| return obj; |
| case DataBuffer.TYPE_USHORT: |
| if (obj == null) |
| obj = new short[1]; |
| ((short[]) obj)[0] = (short) pixel; |
| return obj; |
| case DataBuffer.TYPE_INT: |
| if (obj == null) |
| obj = new int[1]; |
| ((int[]) obj)[0] = pixel; |
| return obj; |
| default: |
| // Seems like the only sensible thing to do. |
| throw new ClassCastException(); |
| } |
| } |
| |
| /** |
| * Returns an array (of length 1) containing the sample for the pixel at |
| * (x, y) in the specified data buffer. If <code>iArray</code> is not |
| * <code>null</code>, it will be populated with the sample value and |
| * returned as the result of this function (this avoids allocating a new |
| * array instance). |
| * |
| * @param x the x-coordinate of the pixel. |
| * @param y the y-coordinate of the pixel. |
| * @param iArray an array to populate with the sample values and return as |
| * the result (if <code>null</code>, a new array will be allocated). |
| * @param data the data buffer (<code>null</code> not permitted). |
| * |
| * @return An array containing the pixel sample value. |
| * |
| * @throws NullPointerException if <code>data</code> is <code>null</code>. |
| */ |
| public int[] getPixel(int x, int y, int[] iArray, DataBuffer data) |
| { |
| if (iArray == null) |
| iArray = new int[1]; |
| iArray[0] = getSample(x, y, 0, data); |
| return iArray; |
| } |
| |
| /** |
| * Returns the sample value for the pixel at (x, y) in the specified data |
| * buffer. |
| * |
| * @param x the x-coordinate of the pixel. |
| * @param y the y-coordinate of the pixel. |
| * @param b the band (in the range <code>0</code> to |
| * <code>getNumBands() - 1</code>). |
| * @param data the data buffer (<code>null</code> not permitted). |
| * |
| * @return The sample value. |
| * |
| * @throws NullPointerException if <code>data</code> is <code>null</code>. |
| */ |
| public int getSample(int x, int y, int b, DataBuffer data) |
| { |
| int pos = |
| ((dataBitOffset + x * numberOfBits) % elemBits) / numberOfBits; |
| int offset = getOffset(x, y); |
| int samples = data.getElem(offset); |
| return (samples & bitMasks[pos]) >>> bitOffsets[pos]; |
| } |
| |
| /** |
| * Set the pixel at x, y to the value in the first element of the primitive |
| * array obj. |
| * |
| * @param x The x-coordinate of the data elements in <code>obj</code>. |
| * @param y The y-coordinate of the data elements in <code>obj</code>. |
| * @param obj The primitive array containing the data elements to set. |
| * @param data The DataBuffer to store the data elements into. |
| */ |
| public void setDataElements(int x, int y, Object obj, DataBuffer data) |
| { |
| int transferType = getTransferType(); |
| try |
| { |
| switch (transferType) |
| { |
| case DataBuffer.TYPE_BYTE: |
| { |
| byte[] in = (byte[]) obj; |
| setSample(x, y, 0, in[0] & 0xFF, data); |
| return; |
| } |
| case DataBuffer.TYPE_USHORT: |
| { |
| short[] in = (short[]) obj; |
| setSample(x, y, 0, in[0] & 0xFFFF, data); |
| return; |
| } |
| case DataBuffer.TYPE_INT: |
| { |
| int[] in = (int[]) obj; |
| setSample(x, y, 0, in[0], data); |
| return; |
| } |
| default: |
| throw new ClassCastException("Unsupported data type"); |
| } |
| } |
| catch (ArrayIndexOutOfBoundsException aioobe) |
| { |
| String msg = "While writing data elements" + |
| ", x=" + x + ", y=" + y + |
| ", width=" + width + ", height=" + height + |
| ", scanlineStride=" + scanlineStride + |
| ", offset=" + getOffset(x, y) + |
| ", data.getSize()=" + data.getSize() + |
| ", data.getOffset()=" + data.getOffset() + |
| ": " + aioobe; |
| throw new ArrayIndexOutOfBoundsException(msg); |
| } |
| } |
| |
| /** |
| * Sets the sample value for the pixel at (x, y) in the specified data |
| * buffer to the specified value. |
| * |
| * @param x the x-coordinate of the pixel. |
| * @param y the y-coordinate of the pixel. |
| * @param iArray the sample value (<code>null</code> not permitted). |
| * @param data the data buffer (<code>null</code> not permitted). |
| * |
| * @throws NullPointerException if either <code>iArray</code> or |
| * <code>data</code> is <code>null</code>. |
| * |
| * @see #setSample(int, int, int, int, DataBuffer) |
| */ |
| public void setPixel(int x, int y, int[] iArray, DataBuffer data) |
| { |
| setSample(x, y, 0, iArray[0], data); |
| } |
| |
| /** |
| * Sets the sample value for a band for the pixel at (x, y) in the |
| * specified data buffer. |
| * |
| * @param x the x-coordinate of the pixel. |
| * @param y the y-coordinate of the pixel. |
| * @param b the band (in the range <code>0</code> to |
| * <code>getNumBands() - 1</code>). |
| * @param s the sample value. |
| * @param data the data buffer (<code>null</code> not permitted). |
| * |
| * @throws NullPointerException if <code>data</code> is <code>null</code>. |
| */ |
| public void setSample(int x, int y, int b, int s, DataBuffer data) |
| { |
| int bitpos = |
| ((dataBitOffset + x * numberOfBits) % elemBits) / numberOfBits; |
| int offset = getOffset(x, y); |
| |
| s = s << bitOffsets[bitpos]; |
| s = s & bitMasks[bitpos]; |
| |
| int sample = data.getElem(offset); |
| sample |= s; |
| data.setElem(offset, sample); |
| } |
| |
| /** |
| * Tests this sample model for equality with an arbitrary object. This |
| * method returns <code>true</code> if and only if: |
| * <ul> |
| * <li><code>obj</code> is not <code>null</code>; |
| * <li><code>obj</code> is an instance of |
| * <code>MultiPixelPackedSampleModel</code>; |
| * <li>both models have the same: |
| * <ul> |
| * <li><code>dataType</code>; |
| * <li><code>width</code>; |
| * <li><code>height</code>; |
| * <li><code>numberOfBits</code>; |
| * <li><code>scanlineStride</code>; |
| * <li><code>dataBitOffsets</code>. |
| * </ul> |
| * </li> |
| * </ul> |
| * |
| * @param obj the object (<code>null</code> permitted) |
| * |
| * @return <code>true</code> if this model is equal to <code>obj</code>, and |
| * <code>false</code> otherwise. |
| */ |
| public boolean equals(Object obj) |
| { |
| if (this == obj) |
| return true; |
| if (! (obj instanceof MultiPixelPackedSampleModel)) |
| return false; |
| MultiPixelPackedSampleModel that = (MultiPixelPackedSampleModel) obj; |
| if (this.dataType != that.dataType) |
| return false; |
| if (this.width != that.width) |
| return false; |
| if (this.height != that.height) |
| return false; |
| if (this.numberOfBits != that.numberOfBits) |
| return false; |
| if (this.scanlineStride != that.scanlineStride) |
| return false; |
| if (this.dataBitOffset != that.dataBitOffset) |
| return false; |
| return true; |
| } |
| |
| /** |
| * Returns a hash code for this <code>MultiPixelPackedSampleModel</code>. |
| * |
| * @return A hash code. |
| */ |
| public int hashCode() |
| { |
| // this hash code won't match Sun's, but that shouldn't matter... |
| int result = 193; |
| result = 37 * result + dataType; |
| result = 37 * result + width; |
| result = 37 * result + height; |
| result = 37 * result + numberOfBits; |
| result = 37 * result + scanlineStride; |
| result = 37 * result + dataBitOffset; |
| return result; |
| } |
| |
| /** |
| * Creates a String with some information about this SampleModel. |
| * @return A String describing this SampleModel. |
| * @see java.lang.Object#toString() |
| */ |
| public String toString() |
| { |
| StringBuffer result = new StringBuffer(); |
| result.append(getClass().getName()); |
| result.append("["); |
| result.append("scanlineStride=").append(scanlineStride); |
| for(int i=0; i < bitMasks.length; i+=1) |
| { |
| result.append(", mask[").append(i).append("]=0x").append(Integer.toHexString(bitMasks[i])); |
| } |
| |
| result.append("]"); |
| return result.toString(); |
| } |
| } |