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* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
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* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Oracle designates this
* particular file as subject to the "Classpath" exception as provided
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*
* This code 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
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
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*
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package java.awt.image;
import java.awt.color.ICC_Profile;
import java.awt.geom.Rectangle2D;
import java.awt.Rectangle;
import java.awt.RenderingHints;
import java.awt.geom.Point2D;
import sun.awt.image.ImagingLib;
/** {@collect.stats}
* This class implements a convolution from the source
* to the destination.
* Convolution using a convolution kernel is a spatial operation that
* computes the output pixel from an input pixel by multiplying the kernel
* with the surround of the input pixel.
* This allows the output pixel to be affected by the immediate neighborhood
* in a way that can be mathematically specified with a kernel.
*<p>
* This class operates with BufferedImage data in which color components are
* premultiplied with the alpha component. If the Source BufferedImage has
* an alpha component, and the color components are not premultiplied with
* the alpha component, then the data are premultiplied before being
* convolved. If the Destination has color components which are not
* premultiplied, then alpha is divided out before storing into the
* Destination (if alpha is 0, the color components are set to 0). If the
* Destination has no alpha component, then the resulting alpha is discarded
* after first dividing it out of the color components.
* <p>
* Rasters are treated as having no alpha channel. If the above treatment
* of the alpha channel in BufferedImages is not desired, it may be avoided
* by getting the Raster of a source BufferedImage and using the filter method
* of this class which works with Rasters.
* <p>
* If a RenderingHints object is specified in the constructor, the
* color rendering hint and the dithering hint may be used when color
* conversion is required.
*<p>
* Note that the Source and the Destination may not be the same object.
* @see Kernel
* @see java.awt.RenderingHints#KEY_COLOR_RENDERING
* @see java.awt.RenderingHints#KEY_DITHERING
*/
public class ConvolveOp implements BufferedImageOp, RasterOp {
Kernel kernel;
int edgeHint;
RenderingHints hints;
/** {@collect.stats}
* Edge condition constants.
*/
/** {@collect.stats}
* Pixels at the edge of the destination image are set to zero. This
* is the default.
*/
public static final int EDGE_ZERO_FILL = 0;
/** {@collect.stats}
* Pixels at the edge of the source image are copied to
* the corresponding pixels in the destination without modification.
*/
public static final int EDGE_NO_OP = 1;
/** {@collect.stats}
* Constructs a ConvolveOp given a Kernel, an edge condition, and a
* RenderingHints object (which may be null).
* @param kernel the specified <code>Kernel</code>
* @param edgeCondition the specified edge condition
* @param hints the specified <code>RenderingHints</code> object
* @see Kernel
* @see #EDGE_NO_OP
* @see #EDGE_ZERO_FILL
* @see java.awt.RenderingHints
*/
public ConvolveOp(Kernel kernel, int edgeCondition, RenderingHints hints) {
this.kernel = kernel;
this.edgeHint = edgeCondition;
this.hints = hints;
}
/** {@collect.stats}
* Constructs a ConvolveOp given a Kernel. The edge condition
* will be EDGE_ZERO_FILL.
* @param kernel the specified <code>Kernel</code>
* @see Kernel
* @see #EDGE_ZERO_FILL
*/
public ConvolveOp(Kernel kernel) {
this.kernel = kernel;
this.edgeHint = EDGE_ZERO_FILL;
}
/** {@collect.stats}
* Returns the edge condition.
* @return the edge condition of this <code>ConvolveOp</code>.
* @see #EDGE_NO_OP
* @see #EDGE_ZERO_FILL
*/
public int getEdgeCondition() {
return edgeHint;
}
/** {@collect.stats}
* Returns the Kernel.
* @return the <code>Kernel</code> of this <code>ConvolveOp</code>.
*/
public final Kernel getKernel() {
return (Kernel) kernel.clone();
}
/** {@collect.stats}
* Performs a convolution on BufferedImages. Each component of the
* source image will be convolved (including the alpha component, if
* present).
* If the color model in the source image is not the same as that
* in the destination image, the pixels will be converted
* in the destination. If the destination image is null,
* a BufferedImage will be created with the source ColorModel.
* The IllegalArgumentException may be thrown if the source is the
* same as the destination.
* @param src the source <code>BufferedImage</code> to filter
* @param dst the destination <code>BufferedImage</code> for the
* filtered <code>src</code>
* @return the filtered <code>BufferedImage</code>
* @throws NullPointerException if <code>src</code> is <code>null</code>
* @throws IllegalArgumentException if <code>src</code> equals
* <code>dst</code>
* @throws ImagingOpException if <code>src</code> cannot be filtered
*/
public final BufferedImage filter (BufferedImage src, BufferedImage dst) {
if (src == null) {
throw new NullPointerException("src image is null");
}
if (src == dst) {
throw new IllegalArgumentException("src image cannot be the "+
"same as the dst image");
}
boolean needToConvert = false;
ColorModel srcCM = src.getColorModel();
ColorModel dstCM;
BufferedImage origDst = dst;
// Can't convolve an IndexColorModel. Need to expand it
if (srcCM instanceof IndexColorModel) {
IndexColorModel icm = (IndexColorModel) srcCM;
src = icm.convertToIntDiscrete(src.getRaster(), false);
srcCM = src.getColorModel();
}
if (dst == null) {
dst = createCompatibleDestImage(src, null);
dstCM = srcCM;
origDst = dst;
}
else {
dstCM = dst.getColorModel();
if (srcCM.getColorSpace().getType() !=
dstCM.getColorSpace().getType())
{
needToConvert = true;
dst = createCompatibleDestImage(src, null);
dstCM = dst.getColorModel();
}
else if (dstCM instanceof IndexColorModel) {
dst = createCompatibleDestImage(src, null);
dstCM = dst.getColorModel();
}
}
if (ImagingLib.filter(this, src, dst) == null) {
throw new ImagingOpException ("Unable to convolve src image");
}
if (needToConvert) {
ColorConvertOp ccop = new ColorConvertOp(hints);
ccop.filter(dst, origDst);
}
else if (origDst != dst) {
java.awt.Graphics2D g = origDst.createGraphics();
try {
g.drawImage(dst, 0, 0, null);
} finally {
g.dispose();
}
}
return origDst;
}
/** {@collect.stats}
* Performs a convolution on Rasters. Each band of the source Raster
* will be convolved.
* The source and destination must have the same number of bands.
* If the destination Raster is null, a new Raster will be created.
* The IllegalArgumentException may be thrown if the source is
* the same as the destination.
* @param src the source <code>Raster</code> to filter
* @param dst the destination <code>WritableRaster</code> for the
* filtered <code>src</code>
* @return the filtered <code>WritableRaster</code>
* @throws NullPointerException if <code>src</code> is <code>null</code>
* @throws ImagingOpException if <code>src</code> and <code>dst</code>
* do not have the same number of bands
* @throws ImagingOpException if <code>src</code> cannot be filtered
* @throws IllegalArgumentException if <code>src</code> equals
* <code>dst</code>
*/
public final WritableRaster filter (Raster src, WritableRaster dst) {
if (dst == null) {
dst = createCompatibleDestRaster(src);
}
else if (src == dst) {
throw new IllegalArgumentException("src image cannot be the "+
"same as the dst image");
}
else if (src.getNumBands() != dst.getNumBands()) {
throw new ImagingOpException("Different number of bands in src "+
" and dst Rasters");
}
if (ImagingLib.filter(this, src, dst) == null) {
throw new ImagingOpException ("Unable to convolve src image");
}
return dst;
}
/** {@collect.stats}
* Creates a zeroed destination image with the correct size and number
* of bands. If destCM is null, an appropriate ColorModel will be used.
* @param src Source image for the filter operation.
* @param destCM ColorModel of the destination. Can be null.
* @return a destination <code>BufferedImage</code> with the correct
* size and number of bands.
*/
public BufferedImage createCompatibleDestImage(BufferedImage src,
ColorModel destCM) {
BufferedImage image;
int w = src.getWidth();
int h = src.getHeight();
WritableRaster wr = null;
if (destCM == null) {
destCM = src.getColorModel();
// Not much support for ICM
if (destCM instanceof IndexColorModel) {
destCM = ColorModel.getRGBdefault();
} else {
/* Create destination image as similar to the source
* as it possible...
*/
wr = src.getData().createCompatibleWritableRaster(w, h);
}
}
if (wr == null) {
/* This is the case when destination color model
* was explicitly specified (and it may be not compatible
* with source raster structure) or source is indexed image.
* We should use destination color model to create compatible
* destination raster here.
*/
wr = destCM.createCompatibleWritableRaster(w, h);
}
image = new BufferedImage (destCM, wr,
destCM.isAlphaPremultiplied(), null);
return image;
}
/** {@collect.stats}
* Creates a zeroed destination Raster with the correct size and number
* of bands, given this source.
*/
public WritableRaster createCompatibleDestRaster(Raster src) {
return src.createCompatibleWritableRaster();
}
/** {@collect.stats}
* Returns the bounding box of the filtered destination image. Since
* this is not a geometric operation, the bounding box does not
* change.
*/
public final Rectangle2D getBounds2D(BufferedImage src) {
return getBounds2D(src.getRaster());
}
/** {@collect.stats}
* Returns the bounding box of the filtered destination Raster. Since
* this is not a geometric operation, the bounding box does not
* change.
*/
public final Rectangle2D getBounds2D(Raster src) {
return src.getBounds();
}
/** {@collect.stats}
* Returns the location of the destination point given a
* point in the source. If dstPt is non-null, it will
* be used to hold the return value. Since this is not a geometric
* operation, the srcPt will equal the dstPt.
*/
public final Point2D getPoint2D(Point2D srcPt, Point2D dstPt) {
if (dstPt == null) {
dstPt = new Point2D.Float();
}
dstPt.setLocation(srcPt.getX(), srcPt.getY());
return dstPt;
}
/** {@collect.stats}
* Returns the rendering hints for this op.
*/
public final RenderingHints getRenderingHints() {
return hints;
}
}