componentsamplemodel.java

JAVA基本类源代码,大家可以学习学习!

    public DataBuffer createDataBuffer() {
        DataBuffer dataBuffer = null;

        int size = (int)getBufferSize();
        switch (dataType) {
        case DataBuffer.TYPE_BYTE:
            dataBuffer = new DataBufferByte(size, numBanks);
            break;
        case DataBuffer.TYPE_USHORT:
            dataBuffer = new DataBufferUShort(size, numBanks);
            break;
        case DataBuffer.TYPE_SHORT:
            dataBuffer = new DataBufferShort(size, numBanks);
            break;
        case DataBuffer.TYPE_INT:
            dataBuffer = new DataBufferInt(size, numBanks);
            break;
        case DataBuffer.TYPE_FLOAT:
            dataBuffer = new DataBufferFloat(size, numBanks);
            break;
        case DataBuffer.TYPE_DOUBLE:
            dataBuffer = new DataBufferDouble(size, numBanks);
            break;
        }

        return dataBuffer;
    }


    /** Gets the offset for the first band of pixel (x,y).
     *  A sample of the first band can be retrieved from a 
     * <code>DataBuffer</code>
     *  <code>data</code> with a <code>ComponentSampleModel</code>
     * <code>csm</code> as
     * <pre>
     *        data.getElem(csm.getOffset(x, y));
     * </pre>
     * @param x,&nbsp;y the location of the pixel
     * @return the offset for the first band of the specified pixel.
     */
    public int getOffset(int x, int y) {
        int offset = y*scanlineStride + x*pixelStride + bandOffsets[0];
        return offset;
    }
 
    /** Gets the offset for band b of pixel (x,y).
     *  A sample of band <code>b</code> can be retrieved from a
     *  <code>DataBuffer</code> <code>data</code>
     *  with a <code>ComponentSampleModel</code> <code>csm</code> as
     * <pre>
     *       data.getElem(csm.getOffset(x, y, b));
     * </pre>
     * @param x,&nbsp;y the location of the specified pixel
     * @param b the specified band
     * @return the offset for the specified band of the specified pixel.
     */
    public int getOffset(int x, int y, int b) {
        int offset = y*scanlineStride + x*pixelStride + bandOffsets[b];
        return offset;
    }
 
    /** Returns the number of bits per sample for all bands. 
     *  @return an array containing the number of bits per sample 
     *          for all bands, where each element in the array 
     *          represents a band.   
     */
    public final int[] getSampleSize() {
        int sampleSize[] = new int [numBands];
        int sizeInBits = getSampleSize(0);

        for (int i=0; i<numBands; i++)
            sampleSize[i] = sizeInBits;

        return sampleSize;
    }

    /** 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.
     */
    public final int getSampleSize(int band) {
        return DataBuffer.getDataTypeSize(dataType);
    }

    /** Returns the bank indices for all bands.
     *  @return the bank indices for all bands.
     */
    public final int [] getBankIndices() {
        return (int[]) bankIndices.clone();
    }

    /** Returns the band offset for all bands.
     *  @return the band offsets for all bands.
     */
    public final int [] getBandOffsets() {
        return (int[])bandOffsets.clone();
    }

    /** Returns the scanline stride of this ComponentSampleModel.
     *  @return the scanline stride of this <code>ComponentSampleModel</code>.
     */
    public final int getScanlineStride() {
        return scanlineStride;
    }

    /** Returns the pixel stride of this ComponentSampleModel.
     *  @return the pixel stride of this <code>ComponentSampleModel</code>.
     */
    public final int getPixelStride() {
        return pixelStride;
    }

    /**
     * Returns the number of data elements needed to transfer a pixel
     * with the 
     * {@link #getDataElements(int, int, Object, DataBuffer) } and 
     * {@link #setDataElements(int, int, Object, DataBuffer) }
     * methods.
     * For a <code>ComponentSampleModel</code>, this is identical to the
     * number of bands.
     * @return the number of data elements needed to transfer a pixel with
     *         the <code>getDataElements</code> and 
     *         <code>setDataElements</code> methods.
     * @see java.awt.image.SampleModel#getNumDataElements
     * @see #getNumBands
     */ 
    public final int getNumDataElements() {
	return getNumBands();
    }

    /** 
     * Returns data for a single pixel in a primitive array of type
     * <code>TransferType</code>.  For a <code>ComponentSampleModel</code>,
     * this is the same as the data type, and samples are returned
     * one per array element.  Generally, <code>obj</code> should
     * be passed in as <code>null</code>, so that the <code>Object</code>
     * is created automatically and is the right primitive data type.
     * <p>
     * The following code illustrates transferring data for one pixel from
     * <code>DataBuffer</code> <code>db1</code>, whose storage layout is 
     * described by <code>ComponentSampleModel</code> <code>csm1</code>, 
     * to <code>DataBuffer</code> <code>db2</code>, whose storage layout 
     * is described by <code>ComponentSampleModel</code> <code>csm2</code>.
     * The transfer is usually more efficient than using 
     * <code>getPixel</code> and <code>setPixel</code>.
     * <pre>
     * 	     ComponentSampleModel csm1, csm2;
     *	     DataBufferInt db1, db2;
     * 	     csm2.setDataElements(x, y,
     *                            csm1.getDataElements(x, y, null, db1), db2);
     * </pre>
     *
     * Using <code>getDataElements</code> and <code>setDataElements</code>
     * to transfer between two <code>DataBuffer/SampleModel</code> 
     * pairs is legitimate if the <code>SampleModel</code> objects have
     * the same number of bands, corresponding bands have the same number of
     * bits per sample, and the <code>TransferType</code>s are the same.
     * <p>
     * If <code>obj</code> is not <code>null</code>, it should be a 
     * primitive array of type <code>TransferType</code>.
     * Otherwise, a <code>ClassCastException</code> is thrown.  An
     * <code>ArrayIndexOutOfBoundsException</code> might be thrown if the 
     * coordinates are not in bounds, or if <code>obj</code> is not 
     * <code>null</code> and is not large enough to hold
     * the pixel data.
     *
     * @param x,&nbsp;y the coordinates of the pixel location
     * @param obj       if non-<code>null</code>, a primitive array
     *                  in which to return the pixel data 
     * @param data      the <code>DataBuffer</code> containing the image data
     * @return the data of the specified pixel
     * @see #setDataElements(int, int, Object, DataBuffer)
     *
     * @throws NullPointerException if data is null.
     * @throws ArrayIndexOutOfBoundsException if the coordinates are
     * not in bounds, or if obj is too small to hold the ouput.
     */
    public Object getDataElements(int x, int y, Object obj, DataBuffer data) {
        if ((x < 0) || (y < 0) || (x >= width) || (y >= height)) {
            throw new ArrayIndexOutOfBoundsException
                ("Coordinate out of bounds!");
        }

	int type = getTransferType();
	int numDataElems = getNumDataElements();
	int pixelOffset = y*scanlineStride + x*pixelStride;

	switch(type) {

	case DataBuffer.TYPE_BYTE:

	    byte[] bdata;

	    if (obj == null)
		bdata = new byte[numDataElems];
	    else
		bdata = (byte[])obj;

	    for (int i=0; i<numDataElems; i++) {
		bdata[i] = (byte)data.getElem(bankIndices[i],
                                              pixelOffset + bandOffsets[i]);
	    }

	    obj = (Object)bdata;
	    break;

	case DataBuffer.TYPE_USHORT:
        case DataBuffer.TYPE_SHORT:
            
	    short[] sdata;

	    if (obj == null)
		sdata = new short[numDataElems];
	    else
		sdata = (short[])obj;

	    for (int i=0; i<numDataElems; i++) {
		sdata[i] = (short)data.getElem(bankIndices[i],
                                               pixelOffset + bandOffsets[i]);
	    }

	    obj = (Object)sdata;
	    break;

	case DataBuffer.TYPE_INT:

	    int[] idata;

	    if (obj == null)
		idata = new int[numDataElems];
	    else
		idata = (int[])obj;

	    for (int i=0; i<numDataElems; i++) {
		idata[i] = data.getElem(bankIndices[i],
                                        pixelOffset + bandOffsets[i]);
	    }

	    obj = (Object)idata;
	    break;

	case DataBuffer.TYPE_FLOAT:

	    float[] fdata;

	    if (obj == null)
		fdata = new float[numDataElems];
	    else
		fdata = (float[])obj;

	    for (int i=0; i<numDataElems; i++) {
		fdata[i] = data.getElemFloat(bankIndices[i],
                                             pixelOffset + bandOffsets[i]);
	    }

	    obj = (Object)fdata;
	    break;

	case DataBuffer.TYPE_DOUBLE:

	    double[] ddata;

	    if (obj == null)
		ddata = new double[numDataElems];
	    else
		ddata = (double[])obj;

	    for (int i=0; i<numDataElems; i++) {
		ddata[i] = data.getElemDouble(bankIndices[i],
                                              pixelOffset + bandOffsets[i]);
	    }

	    obj = (Object)ddata;
	    break;
        }
        
	return obj;
    }

    /**
     * Returns all samples for the specified pixel in an int array,
     * one sample per array element.
     * An <code>ArrayIndexOutOfBoundsException</code> might be thrown if 
     * the coordinates are not in bounds.
     * @param x,&nbsp;y The coordinates of the pixel location
     * @param iArray    If non-null, returns the samples in this array
     * @param data      The DataBuffer containing the image data
     * @return the samples of the specified pixel.
     * @see #setPixel(int, int, int[], DataBuffer)
     *
     * @throws NullPointerException if data is null.
     * @throws ArrayIndexOutOfBoundsException if the coordinates are
     * not in bounds, or if iArray is too small to hold the output.
     */
    public int[] getPixel(int x, int y, int iArray[], DataBuffer data) {
        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 pixelOffset = y*scanlineStride + x*pixelStride;
        for (int i=0; i<numBands; i++) {
            pixels[i] = data.getElem(bankIndices[i],
                                     pixelOffset + bandOffsets[i]);
        }
        return pixels;
    }

    /**
     * Returns all samples for the specified rectangle of pixels in
     * an int array, one sample per array element.
     * An <code>ArrayIndexOutOfBoundsException</code> might be thrown if 
     * the coordinates are not in bounds.
     * @param x,&nbsp;y  the coordinates of the upper left pixel location
     * @param w         The width of the pixel rectangle
     * @param h         The height of the pixel rectangle  
     * @param iArray    If non-null, returns the samples in this array
     * @param data      The DataBuffer containing the image data
     * @return the samples of the pixels within the specified region. 
     * @see #setPixels(int, int, int, int, int[], DataBuffer)
     */
    public int[] getPixels(int x, int y, int w, int h,
                           int iArray[], DataBuffer data) {
        if ((x < 0) || (y < 0) || (x + w > width) || (y + h > height)) {
            throw new ArrayIndexOutOfBoundsException
                ("Coordinate out of bounds!");
        }
        int pixels[];
        if (iArray != null) {
           pixels = iArray;
        } else {
           pixels = new int [w*h*numBands];
        }
        int lineOffset = y*scanlineStride + x*pixelStride;
        int srcOffset = 0;

        for (int i = 0; i < h; i++) {
           int pixelOffset = lineOffset;
           for (int j = 0; j < w; j++) {
              for (int k=0; k < numBands; k++) {
                 pixels[srcOffset++] =
                    data.getElem(bankIndices[k], pixelOffset + bandOffsets[k]);
              }
              pixelOffset += pixelStride;
           }
           lineOffset += scanlineStride;
        }
        return pixels;
    }

    /**
     * Returns as int the sample in a specified band for the pixel
     * located at (x,y).
     * An <code>ArrayIndexOutOfBoundsException</code> might be thrown if 
     * the coordinates are not in bounds.
     * @param x,&nbsp;y  the coordinates of the pixel location
     * @param b         the band to return
     * @param data      the <code>DataBuffer</code> containing the image data
     * @return the sample in a specified band for the specified pixel
     * @see #setSample(int, int, int, int, DataBuffer)
     */
    public int getSample(int x, int y, int b, DataBuffer data) {
        // Bounds check for 'b' will be performed automatically
        if ((x < 0) || (y < 0) || (x >= width) || (y >= height)) {
            throw new ArrayIndexOutOfBoundsException
                ("Coordinate out of bounds!");
        }
        int sample = data.getElem(bankIndices[b],
                                  y*scanlineStride + x*pixelStride +
                                  bandOffsets[b]);
        return sample;
    }

    /**
     * Returns the sample in a specified band
     * for the pixel located at (x,y) as a float.
     * An <code>ArrayIndexOutOfBoundsException</code> might be 
     * thrown if the coordinates are not in bounds.
     * @param x,&nbsp;y  The coordinates of the pixel location
     * @param b         The band to return
     * @param data      The DataBuffer containing the image data
     * @return a float value representing the sample in the specified
     * band for the specified pixel.
     */
    public float getSampleFloat(int x, int y, int b, DataBuffer data) {