BandedSampleModel.java

/* Copyright (C) 2004, 2005, 2006, Free Software Foundation

This file is part of GNU Classpath.

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package java.awt.image;

import gnu.java.awt.Buffers;
import gnu.java.lang.CPStringBuilder;

/**
 * A sample model that reads each sample value from a separate band in the
 * {@link DataBuffer}.
 *
 * @author Jerry Quinn (jlquinn@optonline.net)
 */
public final class BandedSampleModel extends ComponentSampleModel
{
  private int[] bitMasks;
  private int[] bitOffsets;
  private int[] sampleSize;
  private int dataBitOffset;
  private int elemBits;
  private int numberOfBits;
  private int numElems;

  private static int[] createBankArray(int size)
  {
    int[] result = new int[size];
    for (int i = 0; i < size; i++)
      result[i] = i;
    return result;
  }

  /**
   * Creates a new <code>BandedSampleModel</code>.
   *
   * @param dataType  the data buffer type.
   * @param w  the width (in pixels).
   * @param h  the height (in pixels).
   * @param numBands  the number of bands.
   */
  public BandedSampleModel(int dataType, int w, int h, int numBands)
  {
    this(dataType, w, h, w, createBankArray(numBands), new int[numBands]);
  }

  /**
   * Creates a new <code>BandedSampleModel</code>.
   *
   * @param dataType  the data buffer type.
   * @param w  the width (in pixels).
   * @param h  the height (in pixels).
   * @param scanlineStride  the number of data elements from a pixel in one
   *     row to the corresponding pixel in the next row.
   * @param bankIndices  the bank indices.
   * @param bandOffsets  the band offsets.
   */
  public BandedSampleModel(int dataType, int w, int h, int scanlineStride,
                           int[] bankIndices, int[] bandOffsets)
  {
    super(dataType, w, h, 1, scanlineStride, bankIndices, bandOffsets);
  }

  /**
   * Creates a new data buffer that is compatible with this sample model.
   *
   * @return The new data buffer.
   */
  public DataBuffer createDataBuffer()
  {
    int size = scanlineStride * height;
    return Buffers.createBuffer(getDataType(), size, numBanks);
  }

  /**
   * Creates a new <code>SampleModel</code> that is compatible with this
   * model and has the specified width and height.
   *
   * @param w  the width (in pixels, must be greater than zero).
   * @param h  the height (in pixels, must be greater than zero).
   *
   * @return The new sample model.
   *
   * @throws IllegalArgumentException if <code>w</code> or <code>h</code> is
   *     not greater than zero.
   * @throws IllegalArgumentException if <code>w * h</code> exceeds
   *     <code>Integer.MAX_VALUE</code>.
   */
  public SampleModel createCompatibleSampleModel(int w, int h)
  {
    // NOTE: blackdown 1.4.1 sets all offsets to 0.  Sun's 1.4.2 docs
    // disagree.

    // Compress offsets so minimum is 0, others w*scanlineStride
    int[] newoffsets = new int[bandOffsets.length];
    int[] order = new int[bandOffsets.length];
    for (int i = 0; i < bandOffsets.length; i++)
      order[i] = i;
    // FIXME: This is N^2, but not a big issue, unless there's a lot of
    // bands...
    for (int i = 0; i < bandOffsets.length; i++)
      for (int j = i + 1; j < bandOffsets.length; j++)
        if (bankIndices[order[i]] > bankIndices[order[j]]
            || (bankIndices[order[i]] == bankIndices[order[j]]
            && bandOffsets[order[i]] > bandOffsets[order[j]]))
          {
            int t = order[i]; order[i] = order[j]; order[j] = t;
          }
    int bank = 0;
    int offset = 0;
    for (int i = 0; i < bandOffsets.length; i++)
      {
        if (bankIndices[order[i]] != bank)
          {
            bank = bankIndices[order[i]];
            offset = 0;
          }
        newoffsets[order[i]] = offset;
        offset += w * scanlineStride;
      }

    return new BandedSampleModel(dataType, w, h, w, bankIndices, newoffsets);
  }


  public SampleModel createSubsetSampleModel(int[] bands)
  {
    if (bands.length > bankIndices.length)
      throw new
        RasterFormatException("BandedSampleModel createSubsetSampleModel too"
                              +" many bands");
    int[] newoff = new int[bands.length];
    int[] newbanks = new int[bands.length];
    for (int i = 0; i < bands.length; i++)
      {
        int b = bands[i];
        newoff[i] = bandOffsets[b];
        newbanks[i] = bankIndices[b];
      }

    return new BandedSampleModel(dataType, width, height, scanlineStride,
                                 newbanks, newoff);
  }

  /**
   * Extract all samples of one pixel and return in an array of transfer type.
   *
   * Extracts the pixel at x, y from data and stores samples into the array
   * obj.  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,
   *     java.lang.Object, java.awt.image.DataBuffer)
   */
  public Object getDataElements(int x, int y, Object obj, DataBuffer data)
  {
    if (x < 0 || y < 0)
      throw new ArrayIndexOutOfBoundsException(
          "x and y must not be less than 0.");
    int pixel = getSample(x, y, 0, data);
    switch (getTransferType())
    {
    case DataBuffer.TYPE_BYTE:
      {
        byte[] b = (byte[]) obj;
        if (b == null) b = new byte[numBands];
        for (int i = 0; i < numBands; i++)
          b[i] = (byte)getSample(x, y, i, data);
        return b;
      }
    case DataBuffer.TYPE_SHORT:
    case DataBuffer.TYPE_USHORT:
      {
        short[] b = (short[]) obj;
        if (b == null) b = new short[numBands];
        for (int i = 0; i < numBands; i++)
          b[i] = (short)getSample(x, y, i, data);
        return b;
      }
    case DataBuffer.TYPE_INT:
      {
        int[] b = (int[]) obj;
        if (b == null) b = new int[numBands];
        for (int i = 0; i < numBands; i++)
          b[i] = getSample(x, y, i, data);
        return b;
      }
    case DataBuffer.TYPE_FLOAT:
      {
        float[] b = (float[]) obj;
        if (b == null) b = new float[numBands];
        for (int i = 0; i < numBands; i++)
          b[i] = getSampleFloat(x, y, i, data);
        return b;
      }
    case DataBuffer.TYPE_DOUBLE:
      {
        double[] b = (double[]) obj;
        if (b == null)
          b = new double[numBands];
        for (int i = 0; i < numBands; i++)
          b[i] = getSample(x, y, i, data);
        return b;
      }

    default:
      // Seems like the only sensible thing to do.
      throw new ClassCastException();
    }
  }

  /**
   * Returns all the samples for the pixel at location <code>(x, y)</code>
   * stored in the specified data buffer.
   *
   * @param x  the x-coordinate.
   * @param y  the y-coordinate.
   * @param iArray  an array that will be populated with the sample values and
   *   returned as the result.  The size of this array should be equal to the
   *   number of bands in the model.  If the array is <code>null</code>, a new
   *   array is created.
   * @param data  the data buffer (<code>null</code> not permitted).
   *
   * @return The samples for the specified pixel.
   *
   * @see #setPixel(int, int, int[], DataBuffer)
   */
  public int[] getPixel(int x, int y, int[] iArray, DataBuffer data)
  {
    if (iArray == null)
      iArray = new int[numBands];
    for (int i = 0; i < numBands; i++)
      iArray[i] = getSample(x, y, i, data);

    return iArray;
  }

  /**
   * Copy pixels from a region into an array.
   *
   * Copies the samples of the pixels in the rectangle starting at x, y that
   * is w pixels wide and h scanlines high.  When there is more than one band,
   * the samples stored in order before the next pixel.  This ordering isn't
   * well specified in Sun's docs as of 1.4.2.
   *
   * If iArray is null, a new array is allocated, filled, and returned.
   *
   * @param x The x-coordinate of the pixel rectangle to store in
   * <code>iArray</code>.
   * @param y The y-coordinate of the pixel rectangle to store in
   * <code>iArray</code>.
   * @param w The width in pixels of the rectangle.
   * @param h The height in pixels of the rectangle.
   * @param iArray The int 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.
   */
  public int[] getPixels(int x, int y, int w, int h, int[] iArray,
                         DataBuffer data)
  {
    if (x < 0 || y < 0)
      throw new ArrayIndexOutOfBoundsException(
          "x and y must not be less than 0.");
    if (iArray == null)
      iArray = new int[w * h * numBands];
    int outOffset = 0;
    int maxX = x + w;
    int maxY = y + h;
    for (int yy = x; yy < maxY; yy++)
      {
        for (int xx = x; xx < maxX; xx++)
          {
            for (int b = 0; b < numBands; b++)
              {
                int offset = bandOffsets[b] + yy * scanlineStride + xx;
                iArray[outOffset++] =
                  data.getElem(bankIndices[b], offset);
              }
          }
      }
    return iArray;
  }

  /**
   * Returns a 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 offset = bandOffsets[b] + y * scanlineStride + x;
    return data.getElem(bankIndices[b], offset);
  }

  /**
   * Returns a 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>.
   *
   * @see #getSample(int, int, int, DataBuffer)
   */
  public float getSampleFloat(int x, int y, int b, DataBuffer data)
  {
    int offset = bandOffsets[b] + y * scanlineStride + x;
    return data.getElemFloat(bankIndices[b], offset);
  }

  /**
   * 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>.
   *
   * @see #getSample(int, int, int, DataBuffer)
   */
  public double getSampleDouble(int x, int y, int b, DataBuffer data)
  {
    int offset = bandOffsets[b] + y * scanlineStride + x;
    return data.getElemDouble(bankIndices[b], offset);
  }

  /**
   * Copy one band's samples from a region into an array.
   *
   * Copies from one band the samples of the pixels in the rectangle starting
   * at x, y that is w pixels wide and h scanlines high.
   *
   * If iArray is null, a new array is allocated, filled, and returned.
   *
   * @param x The x-coordinate of the pixel rectangle to store in
   * <code>iArray</code>.
   * @param y The y-coordinate of the pixel rectangle to store in
   * <code>iArray</code>.
   * @param w The width in pixels of the rectangle.
   * @param h The height in pixels of the rectangle.
   * @param b The band to retrieve.
   * @param iArray The int 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.
   */
  public int[] getSamples(int x, int y, int w, int h, int b, int[] iArray,
                          DataBuffer data)
  {
    if (x < 0 || y < 0)
      throw new ArrayIndexOutOfBoundsException(
          "x and y must not be less than 0.");
    if (iArray == null)
      iArray = new int[w * h];
    int outOffset = 0;
    int maxX = x + w;
    int maxY = y + h;
    for (int yy = y; yy < maxY; yy++)
      {
        for (int xx = x; xx < maxX; xx++)
          {
            int offset = bandOffsets[b] + yy * scanlineStride + xx;
            iArray[outOffset++] =
              data.getElem(bankIndices[b], offset);
          }
      }
    return iArray;
  }

  /**
   * 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.
   * @see java.awt.image.SampleModel#setDataElements(int, int, int, int, java.lang.Object, java.awt.image.DataBuffer)
   */
  public void setDataElements(int x, int y, Object obj, DataBuffer data)
  {
    int transferType = getTransferType();
    if (getTransferType() != data.getDataType())
      {
        throw new IllegalArgumentException("transfer type ("+
                                           getTransferType()+"), "+
                                           "does not match data "+
                                           "buffer type (" +
                                           data.getDataType() +
                                           ").");
      }

    int offset = y * scanlineStride + x;

    try
      {
        switch (transferType)
          {
          case DataBuffer.TYPE_BYTE:
            {
              DataBufferByte out = (DataBufferByte) data;
              byte[] in = (byte[]) obj;
              for (int i = 0; i < numBands; i++)
                out.getData(bankIndices[i])[offset + bandOffsets[i]] = in[i];
              return;
            }
          case DataBuffer.TYPE_SHORT:
            {
              DataBufferShort out = (DataBufferShort) data;
              short[] in = (short[]) obj;
              for (int i = 0; i < numBands; i++)
                out.getData(bankIndices[i])[offset + bandOffsets[i]] = in[i];
              return;
            }
          case DataBuffer.TYPE_USHORT:
            {
              DataBufferUShort out = (DataBufferUShort) data;
              short[] in = (short[]) obj;
              for (int i = 0; i < numBands; i++)
                out.getData(bankIndices[i])[offset + bandOffsets[i]] = in[i];
              return;
            }
          case DataBuffer.TYPE_INT:
            {
              DataBufferInt out = (DataBufferInt) data;
              int[] in = (int[]) obj;
              for (int i = 0; i < numBands; i++)
                out.getData(bankIndices[i])[offset + bandOffsets[i]] = in[i];
              return;
            }
          case DataBuffer.TYPE_FLOAT:
            {
              DataBufferFloat out = (DataBufferFloat) data;
              float[] in = (float[]) obj;
              for (int i = 0; i < numBands; i++)
                out.getData(bankIndices[i])[offset + bandOffsets[i]] = in[i];
              return;
            }
          case DataBuffer.TYPE_DOUBLE:
            {
              DataBufferDouble out = (DataBufferDouble) data;
              double[] in = (double[]) obj;
              for (int i = 0; i < numBands; i++)
                out.getData(bankIndices[i])[offset + bandOffsets[i]] = in[i];
              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=" + offset
      + ", data.getSize()=" + data.getSize()
      + ", data.getOffset()=" + data.getOffset()
      + ": " + aioobe;
        throw new ArrayIndexOutOfBoundsException(msg);
      }
    }

  /**
   * Sets the samples for the pixel at (x, y) in the specified data buffer to
   * the specified values.
   *
   * @param x  the x-coordinate of the pixel.
   * @param y  the y-coordinate of the pixel.
   * @param iArray  the sample values (<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>.
   */
  public void setPixel(int x, int y, int[] iArray, DataBuffer data)
  {
    for (int b = 0; b < numBands; b++)
      data.setElem(bankIndices[b], bandOffsets[b] + y * scanlineStride + x,
                   iArray[b]);
  }

  /**
   * Sets the sample values for the pixels in the region specified by
   * (x, y, w, h) in the specified data buffer.  The array is
   * ordered by pixels (that is, all the samples for the first pixel are
   * grouped together, followed by all the samples for the second pixel, and so
   * on).
   *
   * @param x  the x-coordinate of the top-left pixel.
   * @param y  the y-coordinate of the top-left pixel.
   * @param w  the width of the region of pixels.
   * @param h  the height of the region of pixels.
   * @param iArray  the pixel sample values (<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>.
   */
  public void setPixels(int x, int y, int w, int h, int[] iArray,
                        DataBuffer data)
  {
    int inOffset = 0;
    for (int hh = 0; hh < h; hh++)
      {
        for (int ww = 0; ww < w; ww++)
          {
            int offset = y * scanlineStride + (x + ww);
            for (int b = 0; b < numBands; b++)
              data.setElem(bankIndices[b], bandOffsets[b] + offset,
                           iArray[inOffset++]);
          }
        y++;
      }
  }

  /**
   * Sets the sample value for band <code>b</code> of the pixel at location
   * <code>(x, y)</code> in the specified data buffer.
   *
   * @param x  the x-coordinate.
   * @param y  the y-coordinate.
   * @param b  the band index.
   * @param s  the sample value.
   * @param data  the data buffer (<code>null</code> not permitted).
   *
   * @see #getSample(int, int, int, DataBuffer)
   */
  public void setSample(int x, int y, int b, int s, DataBuffer data)
  {
    data.setElem(bankIndices[b], bandOffsets[b] + y * scanlineStride + x, s);
  }

  /**
   * 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, float s, DataBuffer data)
  {
    data.setElemFloat(bankIndices[b], bandOffsets[b] + y * scanlineStride + x,
                      s);
  }

  /**
   * 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, double s, DataBuffer data)
  {
    data.setElemDouble(bankIndices[b], bandOffsets[b] + y * scanlineStride + x,
                       s);
  }

  /**
   * Sets the sample values for one band for the pixels in the region
   * specified by (x, y, w, h) in the specified data buffer.
   *
   * @param x  the x-coordinate of the top-left pixel.
   * @param y  the y-coordinate of the top-left pixel.
   * @param w  the width of the region of pixels.
   * @param h  the height of the region of pixels.
   * @param b  the band (in the range <code>0</code> to
   *     </code>getNumBands() - 1</code>).
   * @param iArray  the sample values (<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>.
   */
  public void setSamples(int x, int y, int w, int h, int b, int[] iArray,
                         DataBuffer data)
  {
    if (x < 0 || y < 0)
      throw new ArrayIndexOutOfBoundsException(
          "x and y must not be less than 0.");
    int inOffset = 0;

    switch (getTransferType())
      {
      case DataBuffer.TYPE_BYTE:
        {
          DataBufferByte out = (DataBufferByte) data;
          byte[] bank = out.getData(bankIndices[b]);
          for (int hh = 0; hh < h; hh++)
            {
              for (int ww = 0; ww < w; ww++)
                {
                  int offset = bandOffsets[b] + y * scanlineStride + (x + ww);
                  bank[offset] = (byte)iArray[inOffset++];
                }
              y++;
            }
          return;
        }
      case DataBuffer.TYPE_SHORT:
        {
          DataBufferShort out = (DataBufferShort) data;
          short[] bank = out.getData(bankIndices[b]);
          for (int hh = 0; hh < h; hh++)
            {
              for (int ww = 0; ww < w; ww++)
                {
                  int offset = bandOffsets[b] + y * scanlineStride + (x + ww);
                  bank[offset] = (short)iArray[inOffset++];
                }
              y++;
            }
          return;
        }
      case DataBuffer.TYPE_USHORT:
        {
          DataBufferShort out = (DataBufferShort) data;
          short[] bank = out.getData(bankIndices[b]);
          for (int hh = 0; hh < h; hh++)
            {
              for (int ww = 0; ww < w; ww++)
                {
                  int offset = bandOffsets[b] + y * scanlineStride + (x + ww);
                  bank[offset] = (short)iArray[inOffset++];
                }
              y++;
            }
          return;
        }
      case DataBuffer.TYPE_INT:
        {
          DataBufferInt out = (DataBufferInt) data;
          int[] bank = out.getData(bankIndices[b]);
          for (int hh = 0; hh < h; hh++)
            {
              for (int ww = 0; ww < w; ww++)
                {
                  int offset = bandOffsets[b] + y * scanlineStride + (x + ww);
                  bank[offset] = iArray[inOffset++];
                }
              y++;
            }
          return;
        }
      case DataBuffer.TYPE_FLOAT:
      case DataBuffer.TYPE_DOUBLE:
        break;
      default:
        throw new ClassCastException("Unsupported data type");
      }

    // Default implementation probably slower for float and double
    for (int hh = 0; hh < h; hh++)
      {
        for (int ww = 0; ww < w; ww++)
          {
            int offset = bandOffsets[b] + y * scanlineStride + (x + ww);
            data.setElem(bankIndices[b], offset, iArray[inOffset++]);
          }
        y++;
      }
  }

  /**
   * Creates a String with some information about this SampleModel.
   * @return A String describing this SampleModel.
   * @see java.lang.Object#toString()
   */
  public String toString()
  {
    CPStringBuilder result = new CPStringBuilder();
    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();
  }
}