/**
* Creates a zeroed destination <CODE>Raster</CODE> with the correct size and number of bands. An
* <CODE>IllegalArgumentException</CODE> may be thrown if the number of bands in the source is
* incompatible with the matrix. See the class comments for more details.
*
* @param src The <CODE>Raster</CODE> to be filtered.
* @return The zeroed destination <CODE>Raster</CODE>.
*/
public WritableRaster createCompatibleDestRaster(Raster src) {
int nBands = src.getNumBands();
if ((ncols != nBands) && (ncols != (nBands + 1))) {
throw new IllegalArgumentException(
"Number of columns in the "
+ "matrix ("
+ ncols
+ ") must be equal to the number"
+ " of bands ([+1]) in src ("
+ nBands
+ ").");
}
if (src.getNumBands() == nrows) {
return src.createCompatibleWritableRaster();
} else {
throw new IllegalArgumentException(
"Don't know how to create a " + " compatible Raster with " + nrows + " bands.");
}
}
public final double resample(final Raster raster, final Index index) throws Exception {
final int[] x = new int[kernelSize];
final int[] y = new int[kernelSize];
final double[][] samples = new double[kernelSize][kernelSize];
final double[] winX = new double[kernelSize];
final double cx = index.ki[0] + halfKernelSize;
double sumX = 0.0;
for (int n = 0; n < kernelSize; n++) {
x[n] = (int) index.i[n];
y[n] = (int) index.j[n];
winX[n] = sincHanning(cx - n);
sumX += winX[n];
}
if (!raster.getSamples(x, y, samples)) {
if (Double.isNaN(samples[halfKernelSize][halfKernelSize])) {
return samples[halfKernelSize][halfKernelSize];
}
BiCubicInterpolationResampling.replaceNaNWithMean(samples);
}
final double cy = index.kj[0] + halfKernelSize;
double sumY = 0, winY;
double v = 0.0;
for (int j = 0; j < kernelSize; j++) {
winY = sincHanning(cy - j);
sumY += winY;
for (int i = 0; i < kernelSize; i++) {
v += samples[j][i] * winX[i] * winY;
}
}
v /= sumX * sumY;
return v;
}
/**
* Returns the bounding box of the transformed destination. Since this is not a geometric
* operation, the bounding box is the same for the source and destination. An <CODE>
* IllegalArgumentException</CODE> may be thrown if the number of bands in the source is
* incompatible with the matrix. See the class comments for more details.
*
* @param src The <CODE>Raster</CODE> to be filtered.
* @return The <CODE>Rectangle2D</CODE> representing the destination image's bounding box.
* @throws IllegalArgumentException If the number of bands in the source is incompatible with the
* matrix.
*/
public final Rectangle2D getBounds2D(Raster src) {
return src.getBounds();
}
/**
* Transforms the <CODE>Raster</CODE> using the matrix specified in the constructor. An <CODE>
* IllegalArgumentException</CODE> may be thrown if the number of bands in the source or
* destination is incompatible with the matrix. See the class comments for more details.
*
* <p>If the destination is null, it will be created with a number of bands equalling the number
* of rows in the matrix. No exception is thrown if the operation causes a data overflow.
*
* @param src The <CODE>Raster</CODE> to be filtered.
* @param dst The <CODE>Raster</CODE> in which to store the results of the filter operation.
* @return The filtered <CODE>Raster</CODE>.
* @throws IllegalArgumentException If the number of bands in the source or destination is
* incompatible with the matrix.
*/
public WritableRaster filter(Raster src, WritableRaster dst) {
int nBands = src.getNumBands();
if (ncols != nBands && ncols != (nBands + 1)) {
throw new IllegalArgumentException(
"Number of columns in the "
+ "matrix ("
+ ncols
+ ") must be equal to the number"
+ " of bands ([+1]) in src ("
+ nBands
+ ").");
}
if (dst == null) {
dst = createCompatibleDestRaster(src);
} else if (nrows != dst.getNumBands()) {
throw new IllegalArgumentException(
"Number of rows in the "
+ "matrix ("
+ nrows
+ ") must be equal to the number"
+ " of bands ([+1]) in dst ("
+ nBands
+ ").");
}
if (ImagingLib.filter(this, src, dst) != null) {
return dst;
}
int[] pixel = null;
int[] dstPixel = new int[dst.getNumBands()];
float accum;
int sminX = src.getMinX();
int sY = src.getMinY();
int dminX = dst.getMinX();
int dY = dst.getMinY();
int sX;
int dX;
if (ncols == nBands) {
for (int y = 0; y < src.getHeight(); y++, sY++, dY++) {
dX = dminX;
sX = sminX;
for (int x = 0; x < src.getWidth(); x++, sX++, dX++) {
pixel = src.getPixel(sX, sY, pixel);
for (int r = 0; r < nrows; r++) {
accum = 0.f;
for (int c = 0; c < ncols; c++) {
accum += matrix[r][c] * pixel[c];
}
dstPixel[r] = (int) accum;
}
dst.setPixel(dX, dY, dstPixel);
}
}
} else {
// Need to add constant
for (int y = 0; y < src.getHeight(); y++, sY++, dY++) {
dX = dminX;
sX = sminX;
for (int x = 0; x < src.getWidth(); x++, sX++, dX++) {
pixel = src.getPixel(sX, sY, pixel);
for (int r = 0; r < nrows; r++) {
accum = 0.f;
for (int c = 0; c < nBands; c++) {
accum += matrix[r][c] * pixel[c];
}
dstPixel[r] = (int) (accum + matrix[r][nBands]);
}
dst.setPixel(dX, dY, dstPixel);
}
}
}
return dst;
}
