llvm-gcc-4.2/libjava/classpath/java/awt/image/ColorConvertOp.java

/* ColorConvertOp.java --
   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)
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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
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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
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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
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package java.awt.image;

import java.awt.Graphics2D;
import java.awt.RenderingHints;
import java.awt.color.ColorSpace;
import java.awt.color.ICC_ColorSpace;
import java.awt.color.ICC_Profile;
import java.awt.geom.Point2D;
import java.awt.geom.Rectangle2D;

/**
 * ColorConvertOp is a filter for converting an image from one colorspace to
 * another colorspace.  The filter can convert the image through a sequence
 * of colorspaces or just from source to destination.
 * 
 * Color conversion is done on the color components without alpha.  Thus
 * if a BufferedImage has alpha premultiplied, this is divided out before
 * color conversion, and premultiplication applied if the destination
 * requires it.
 * 
 * Color rendering and dithering hints may be applied if specified.  This is
 * likely platform-dependent.
 * 
 * @author jlquinn@optonline.net
 */
public class ColorConvertOp implements BufferedImageOp, RasterOp
{
  private ColorSpace srccs;
  private ColorSpace dstcs;
  private RenderingHints hints;
  private ICC_Profile[] profiles;
  private ColorSpace[] spaces;
  private boolean rasterValid;
  

  /**
   * Convert BufferedImage through a ColorSpace.
   * 
   * This filter version is only valid for BufferedImages.  The source image
   * is converted to cspace.  If the destination is not null, it is then
   * converted to the destination colorspace.  Normally this filter will only
   * be used with a null destination.
   * 
   * @param cspace The target color space.
   * @param hints Rendering hints to use in conversion, or null.
   */
  public ColorConvertOp(ColorSpace cspace, RenderingHints hints)
  {
    if (cspace == null)
      throw new NullPointerException();
    spaces = new ColorSpace[]{cspace};
    this.hints = hints;
    rasterValid = false;
  }
  
  public ColorConvertOp(ColorSpace srcCspace, ColorSpace dstCspace,
			RenderingHints hints)
  {
    if (srcCspace == null || dstCspace == null)
      throw new NullPointerException();
    spaces = new ColorSpace[]{srcCspace, dstCspace};
    this.hints = hints;     
  }

  /**
   * Convert from a source image destination image color space.
   * 
   * This constructor builds a ColorConvertOp from an array of ICC_Profiles.
   * The source image will be converted through the sequence of color spaces
   * defined by the profiles.  If the sequence of profiles doesn't give a
   * well-defined conversion, throws IllegalArgumentException.
   * 
   * NOTE: Sun's docs don't clearly define what a well-defined conversion is
   *  - or perhaps someone smarter can come along and sort it out.  
   * 
   * For BufferedImages, when the first and last profiles match the
   * requirements of the source and destination color space respectively, the
   * corresponding conversion is unnecessary.  TODO: code this up.  I don't
   * yet understand how you determine this.
   * 
   * For Rasters, the first and last profiles must have the same number of
   * bands as the source and destination Rasters, respectively.  If this is
   * not the case, or there fewer than 2 profiles, an IllegalArgumentException
   * will be thrown. 
   * 
   * @param profiles
   * @param hints
   */
  public ColorConvertOp(ICC_Profile[] profiles, RenderingHints hints)
  {
    if (profiles == null)
      throw new NullPointerException();
    this.hints = hints; 
    this.profiles = profiles;
    // TODO: Determine if this is well-defined.
    // Create colorspace array with space for src and dest colorspace
    spaces = new ColorSpace[profiles.length];
    for (int i = 0; i < profiles.length; i++)
      spaces[i] = new ICC_ColorSpace(profiles[i]);
  }
  
  /** Convert from source image color space to destination image color space.
   * 
   * Only valid for BufferedImage objects, this Op converts from the source
   * color space to the destination color space.  The destination can't be
   * null for this operation.
   * 
   * @param hints Rendering hints to use during conversion, or null.
   */
  public ColorConvertOp(RenderingHints hints)
  {
    this.hints = hints; 
    srccs = null;
    dstcs = null;
    rasterValid = false;
  }
  
  /* (non-Javadoc)
   * @see java.awt.image.BufferedImageOp#filter(java.awt.image.BufferedImage,
   java.awt.image.BufferedImage)
   */
  public final BufferedImage filter(BufferedImage src, BufferedImage dst)
  {
    // TODO: The plan is to create a scanline buffer for intermediate buffers.
    // For now we just suck it up and create intermediate buffers.
    
    if (dst == null && spaces.length == 0)
      throw new IllegalArgumentException();

    // Make sure input isn't premultiplied by alpha
    if (src.isAlphaPremultiplied())
    {
      BufferedImage tmp = createCompatibleDestImage(src, src.getColorModel());
      copyimage(src, tmp);
      tmp.coerceData(false);
      src = tmp;
    }

    ColorModel scm = src.getColorModel();
    for (int i = 0; i < spaces.length; i++)
    {
      BufferedImage tmp = createCompatibleDestImage(src, scm);
      copyimage(src, tmp);
      src = tmp;
    }

    // Intermediate conversions leave result in src
    if (dst == null)
      return src;
    
    // Apply final conversion
    copyimage(src, dst);
    
    return dst;
  }

  /* (non-Javadoc)
   * @see java.awt.image.BufferedImageOp#createCompatibleDestImage(java.awt.image.BufferedImage, java.awt.image.ColorModel)
   */
  public BufferedImage createCompatibleDestImage(BufferedImage src,
						 ColorModel dstCM)
  {
    // FIXME: set properties to those in src
    return new BufferedImage(dstCM,
			     src.getRaster().createCompatibleWritableRaster(),
			     src.isPremultiplied,
			     null);
  }
  
  public final ICC_Profile[] getICC_Profiles()
  {
    return profiles;
  }

  /** Return the rendering hints for this op. */
  public final RenderingHints getRenderingHints()
  {
    return hints;
  }

  /* (non-Javadoc)
   * @see java.awt.image.RasterOp#filter(java.awt.image.Raster, java.awt.image.WritableRaster)
   */
  public final WritableRaster filter(Raster src, WritableRaster dest)
  {
    if (!rasterValid)
      throw new IllegalArgumentException();
    
    // Need to iterate through each color space - there must be at least 2
    for (int i = 1; i < spaces.length - 1; i++)
    {
      // FIXME: this is wrong.  tmp needs to have the same number of bands as
      // spaces[i] has.
      WritableRaster tmp = createCompatibleDestRaster(src);
      copyraster(src, spaces[i - 1], tmp, spaces[i]);
      src = tmp;
    }
    
    // FIXME: this is wrong.  dst needs to have the same number of bands as
    // spaces[i] has.
    if (dest == null)
      dest = createCompatibleDestRaster(src);
    copyraster(src, spaces[spaces.length - 2],
	       dest, spaces[spaces.length - 1]);
    
    return dest;
  }

  /* (non-Javadoc)
   * @see java.awt.image.RasterOp#createCompatibleDestRaster(java.awt.image.Raster)
   */
  public WritableRaster createCompatibleDestRaster(Raster src)
  {
    return src.createCompatibleWritableRaster();
  }

  /** Return corresponding destination point for source point.
   * 
   * LookupOp will return the value of src unchanged.
   * @param src The source point.
   * @param dst The destination point.
   * @see java.awt.image.RasterOp#getPoint2D(java.awt.geom.Point2D, java.awt.geom.Point2D)
   */
  public final Point2D getPoint2D(Point2D src, Point2D dst)
  {
    if (dst == null) return (Point2D)src.clone();
    dst.setLocation(src);
    return dst;
  }

  /* (non-Javadoc)
   * @see java.awt.image.BufferedImageOp#getBounds2D(java.awt.image.BufferedImage)
   */
  public final Rectangle2D getBounds2D(BufferedImage src)
  {
    return src.getRaster().getBounds();
  }

  /* (non-Javadoc)
   * @see java.awt.image.RasterOp#getBounds2D(java.awt.image.Raster)
   */
  public final Rectangle2D getBounds2D(Raster src)
  {
    return src.getBounds();
  }
  
  // According to Sven de Marothy, we need to copy the src into the dest
  // using Graphics2D, in order to use the rendering hints.
  private void copyimage(BufferedImage src, BufferedImage dst)
  {
    Graphics2D gg = dst.createGraphics();
    
    // If no hints are set there is no need to call
    // setRenderingHints on the Graphics2D object.
    if (hints != null)
      gg.setRenderingHints(hints);
    
    gg.drawImage(src, 0, 0, null);
    gg.dispose();
  }
  
  private void copyraster(Raster src, ColorSpace scs, WritableRaster dst,
      					  ColorSpace dcs)
  {
    float[] sbuf = new float[src.getNumBands()];
    
    if (hints.get(RenderingHints.KEY_COLOR_RENDERING) ==
        RenderingHints.VALUE_COLOR_RENDER_QUALITY)
    {
      // use cie for accuracy
      for (int y = src.getMinY(); y < src.getHeight() + src.getMinY(); y++)
        for (int x = src.getMinX(); x < src.getWidth() + src.getMinX(); x++)
          dst.setPixel(x, y,
		       dcs.fromCIEXYZ(scs.toCIEXYZ(src.getPixel(x, y, sbuf))));
    }
    else
    {
      // use rgb - it's probably faster
      for (int y = src.getMinY(); y < src.getHeight() + src.getMinY(); y++)
        for (int x = src.getMinX(); x < src.getWidth() + src.getMinX(); x++)
          dst.setPixel(x, y,
		       dcs.fromRGB(scs.toRGB(src.getPixel(x, y, sbuf))));
    }
  }

}