46 lines (34 with data), 1.3 kB

/*
 * Transform histogram of an image to match another image
 *   version to be used inside a IJ macro:
 *  > bshText = File.openAsString( "%s" );  // open script as text
 *  > eval("bsh", bshText );  // evaluate script
 *
 * Copyright (C) 2019 Ignacio Arganda-Carreras <ignacio.arganda@ehu.eus>
 */

import ij.IJ;
import histogram2.HistogramMatcher;
import ij.process.StackStatistics;
import ij.ImageStack;
import ij.ImagePlus;
import ij.WindowManager;

targetImage = WindowManager.getImage( "targetImage" );
sourceImage = WindowManager.getImage( "sourceImage" );


stats1 = new StackStatistics( sourceImage );
stats2 = new StackStatistics( targetImage );

hist1 = stats1.histogram; // ip1.getHistogram();
hist2 = stats2.histogram; // ip2.getHistogram();

matcher = new HistogramMatcher();
newHist = matcher.matchHistograms(hist1, hist2);

//ip1.applyTable(newHist);
//sourceImage.setProcessor(ip1);

is = new ImageStack( sourceImage.getWidth(), sourceImage.getHeight() );

boolean isStack = sourceImage.getImageStackSize() > 1;

for( n=1; n<=sourceImage.getImageStackSize(); n++)
{
	ip = sourceImage.getImageStack().getProcessor( n );
	ip.applyTable(newHist);
	label = isStack ? sourceImage.getImageStack().getSliceLabel( n ) : "";
	is.addSlice( label, ip );
}

sourceImage.setStack( is );