private synchronized void computeHistogram(Rectangle visibleRect, PlanarImage image) {
int channels = image.getSampleModel().getNumBands();
Histogram hist = new Histogram(256, 256, 512, channels);
bins = hist.getBins();
// Raster raster = image.getData(visibleRect);
Rectangle bounds = visibleRect; // image.getBounds();
int pixel[] = null;
int maxPixels = 256;
int incX = bounds.width >= 2 * maxPixels ? bounds.width / maxPixels : 1;
int incY = bounds.height >= 2 * maxPixels ? bounds.height / maxPixels : 1;
double log2 = Math.log(2);
int minTileX = image.XToTileX(bounds.x);
int maxTileX = image.XToTileX(bounds.x + bounds.width - 1);
int minTileY = image.YToTileY(bounds.y);
int maxTileY = image.YToTileY(bounds.y + bounds.height - 1);
for (int tx = minTileX; tx <= maxTileX; tx++)
for (int ty = minTileY; ty <= maxTileY; ty++) {
Raster raster = image.getTile(tx, ty);
int minX = Math.max(bounds.x, raster.getMinX());
int maxX = Math.min(bounds.x + bounds.width, raster.getMinX() + raster.getWidth());
int minY = Math.max(bounds.y, raster.getMinY());
int maxY = Math.min(bounds.y + bounds.height, raster.getMinY() + raster.getHeight());
for (int x = minX; x < maxX; x += incX)
for (int y = minY; y < maxY; y += incY) {
pixel = raster.getPixel(x, y, pixel);
for (int c = 0; c < channels; c++) {
int v = (int) (511 * logTable[pixel[c]] / (16 * log2));
if (v > 255) bins[c][v - 256]++;
else bins[c][0]++;
}
}
}
bins = hist.getBins();
}
private BufferedImage cropScaleGrayscale(Rectangle visibleRect, RenderedImage image) {
int minX = image.getMinX();
int minY = image.getMinY();
int width = image.getWidth();
int height = image.getHeight();
Rectangle bounds = new Rectangle(minX, minY, width, height);
visibleRect = bounds.intersection(visibleRect);
if (bounds.contains(visibleRect)) {
ParameterBlock pb = new ParameterBlock();
pb.addSource(image);
pb.add((float) visibleRect.x);
pb.add((float) visibleRect.y);
pb.add((float) visibleRect.width);
pb.add((float) visibleRect.height);
image = JAI.create("Crop", pb, JAIContext.noCacheHint);
}
Dimension previewSize = getSize();
if ((visibleRect.width > previewSize.width) || (visibleRect.height > previewSize.height)) {
float scale =
Math.min(
previewSize.width / (float) visibleRect.width,
previewSize.height / (float) visibleRect.height);
image = ConvolveDescriptor.create(image, Functions.getGaussKernel(.25 / scale), null);
ParameterBlock pb = new ParameterBlock();
pb.addSource(image);
pb.add(scale);
pb.add(scale);
image = JAI.create("Scale", pb, JAIContext.noCacheHint);
}
image = Functions.toColorSpace(image, JAIContext.systemColorSpace, null);
if (image.getSampleModel().getDataType() == DataBuffer.TYPE_USHORT) {
image = Functions.fromUShortToByte(image, null);
}
return Functions.toFastBufferedImage(image);
}
