/* * Copyright (C) 2011-2012 Dr. John Lindsay <jlindsay@uoguelph.ca> * * This program 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 3 of the License, or * (at your option) any later version. * * This program 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 for more details. * * You should have received a copy of the GNU General Public License * along with this program. If not, see <http://www.gnu.org/licenses/>. */ package plugins; import java.awt.Color; import java.util.Date; import whitebox.geospatialfiles.WhiteboxRaster; import whitebox.interfaces.WhiteboxPlugin; import whitebox.interfaces.WhiteboxPluginHost; /** * This tool alters the cumulative distribution function (CDF) of a raster image to match, as closely as possible, the CDF of a uniform distribution. * @author Dr. John Lindsay email: jlindsay@uoguelph.ca */ public class HistogramEqualization implements WhiteboxPlugin { private WhiteboxPluginHost myHost = null; private String[] args; /** * Used to retrieve the plugin tool's name. This is a short, unique name containing no spaces. * @return String containing plugin name. */ @Override public String getName() { return "HistogramEqualization"; } /** * Used to retrieve the plugin tool's descriptive name. This can be a longer name (containing spaces) and is used in the interface to list the tool. * @return String containing the plugin descriptive name. */ @Override public String getDescriptiveName() { return "Histogram Equalization"; } /** * Used to retrieve a short description of what the plugin tool does. * @return String containing the plugin's description. */ @Override public String getToolDescription() { return "Performs a histogram equalization contrast enhancment on an image."; } /** * Used to identify which toolboxes this plugin tool should be listed in. * @return Array of Strings. */ @Override public String[] getToolbox() { String[] ret = { "ImageEnhancement" }; return ret; } /** * Sets the WhiteboxPluginHost to which the plugin tool is tied. This is the class * that the plugin will send all feedback messages, progress updates, and return objects. * @param host The WhiteboxPluginHost that called the plugin tool. */ @Override public void setPluginHost(WhiteboxPluginHost host) { myHost = host; } /** * Used to communicate feedback pop-up messages between a plugin tool and the main Whitebox user-interface. * @param feedback String containing the text to display. */ private void showFeedback(String message) { if (myHost != null) { myHost.showFeedback(message); } else { System.out.println(message); } } /** * Used to communicate a return object from a plugin tool to the main Whitebox user-interface. * @return Object, such as an output WhiteboxRaster. */ private void returnData(Object ret) { if (myHost != null) { myHost.returnData(ret); } } private int previousProgress = 0; private String previousProgressLabel = ""; /** * Used to communicate a progress update between a plugin tool and the main Whitebox user interface. * @param progressLabel A String to use for the progress label. * @param progress Float containing the progress value (between 0 and 100). */ private void updateProgress(String progressLabel, int progress) { if (myHost != null && ((progress != previousProgress) || (!progressLabel.equals(previousProgressLabel)))) { myHost.updateProgress(progressLabel, progress); } previousProgress = progress; previousProgressLabel = progressLabel; } /** * Used to communicate a progress update between a plugin tool and the main Whitebox user interface. * @param progress Float containing the progress value (between 0 and 100). */ private void updateProgress(int progress) { if (myHost != null && progress != previousProgress) { myHost.updateProgress(progress); } previousProgress = progress; } /** * Sets the arguments (parameters) used by the plugin. * @param args An array of string arguments. */ @Override public void setArgs(String[] args) { this.args = args.clone(); } private boolean cancelOp = false; /** * Used to communicate a cancel operation from the Whitebox GUI. * @param cancel Set to true if the plugin should be canceled. */ @Override public void setCancelOp(boolean cancel) { cancelOp = cancel; } private void cancelOperation() { showFeedback("Operation cancelled."); updateProgress("Progress: ", 0); } private boolean amIActive = false; /** * Used by the Whitebox GUI to tell if this plugin is still running. * @return a boolean describing whether or not the plugin is actively being used. */ @Override public boolean isActive() { return amIActive; } /** * Used to execute this plugin tool. */ @Override public void run() { amIActive = true; String outputHeader = null; String inputFilesString = null; String outputFileSuffix = "_HistoEqual"; WhiteboxRaster image = null; WhiteboxRaster output = null; int row, col; int rows = 0; int cols = 0; double z; float progress = 0; long numCells = 0; int i = 0; String[] imageFiles; int numImages = 0; double noData = -32768; int numBins = 1024; if (args.length <= 0) { showFeedback("Plugin parameters have not been set."); return; } inputFilesString = args[0]; outputFileSuffix = args[1]; numBins = Integer.parseInt(args[2]); // check to see that the inputHeader and outputHeader are not null. if ((inputFilesString == null) || (outputFileSuffix == null)) { showFeedback("One or more of the input parameters have not been set properly."); return; } imageFiles = inputFilesString.split(";"); numImages = imageFiles.length; try { for (i = 0; i < numImages; i++) { image = new WhiteboxRaster(imageFiles[i], "r"); noData = image.getNoDataValue(); rows = image.getNumberRows(); cols = image.getNumberColumns(); outputHeader = imageFiles[i].replace(".dep", outputFileSuffix + ".dep"); output = new WhiteboxRaster(outputHeader, "rw", imageFiles[i], WhiteboxRaster.DataType.INTEGER, noData); output.setPreferredPalette(image.getPreferredPalette()); double minValue = image.getMinimumValue(); double maxValue = image.getMaximumValue(); double binSize = (maxValue - minValue) / numBins; long[] histogram = new long[numBins]; int binNum; int numBinsLessOne = numBins - 1; double[] data; if (image.getDataScale() != WhiteboxRaster.DataScale.RGB) { updateProgress("Loop 1 of 2:", 0); for (row = 0; row < rows; row++) { data = image.getRowValues(row); for (col = 0; col < cols; col++) { if (data[col] != noData) { numCells++; binNum = (int) ((data[col] - minValue) / binSize); if (binNum > numBinsLessOne) { binNum = numBinsLessOne; } histogram[binNum]++; } } if (cancelOp) { cancelOperation(); return; } progress = (float) (100f * row / (rows - 1)); updateProgress("Loop 1 of 2:", (int) progress); } double[] cdf = new double[numBins]; cdf[0] = histogram[0]; for (int j = 1; j < numBins; j++) { cdf[j] = cdf[j - 1] + histogram[j]; } histogram = null; updateProgress("Loop 2 of 2:", 0); for (row = 0; row < rows; row++) { data = image.getRowValues(row); for (col = 0; col < cols; col++) { if (data[col] != noData) { binNum = (int) ((data[col] - minValue) / binSize); if (binNum > numBinsLessOne) { binNum = numBinsLessOne; } z = Math.round((cdf[binNum] - cdf[0]) / (numCells - cdf[0]) * numBinsLessOne); output.setValue(row, col, z); } } if (cancelOp) { cancelOperation(); return; } progress = (float) (100f * row / (rows - 1)); updateProgress("Loop 2 of 2:", (int) progress); } } else { output = new WhiteboxRaster(outputHeader, "rw", imageFiles[i], WhiteboxRaster.DataType.FLOAT, noData); output.setPreferredPalette(image.getPreferredPalette()); output.setDataScale(WhiteboxRaster.DataScale.RGB); // convert the rgb to hsv and calculate the histogram for the 'v' double h, s, v; int a, r, g, b; minValue = 99999999; maxValue = -99999999; float[] hsbvals = new float[3]; float[] rgbvals = new float[3]; updateProgress("Loop 1 of 3:", 0); for (row = 0; row < rows; row++) { data = image.getRowValues(row); for (col = 0; col < cols; col++) { if (data[col] != noData) { r = (int) data[col] & 0xFF; g = ((int) data[col] >> 8) & 0xFF; b = ((int) data[col] >> 16) & 0xFF; Color.RGBtoHSB(r, g, b, hsbvals); v = hsbvals[2]; if (v < minValue) { minValue = v; } if (v > maxValue) { maxValue = v; } } } if (cancelOp) { cancelOperation(); return; } progress = (float) (100f * row / (rows - 1)); updateProgress("Loop 1 of 3:", (int) progress); } binSize = (maxValue - minValue) / numBins; histogram = new long[numBins]; numBinsLessOne = numBins - 1; updateProgress("Loop 2 of 3:", 0); for (row = 0; row < rows; row++) { data = image.getRowValues(row); for (col = 0; col < cols; col++) { if (data[col] != noData) { r = (int) data[col] & 0xFF; g = ((int) data[col] >> 8) & 0xFF; b = ((int) data[col] >> 16) & 0xFF; Color.RGBtoHSB(r, g, b, hsbvals); v = hsbvals[2]; numCells++; binNum = (int) ((v - minValue) / binSize); if (binNum > numBinsLessOne) { binNum = numBinsLessOne; } histogram[binNum]++; } } if (cancelOp) { cancelOperation(); return; } progress = (float) (100f * row / (rows - 1)); updateProgress("Loop 2 of 3:", (int) progress); } double[] cdf = new double[numBins]; cdf[0] = histogram[0]; for (int j = 1; j < numBins; j++) { cdf[j] = cdf[j - 1] + histogram[j]; } histogram = null; updateProgress("Loop 3 of 3:", 0); float val = 0; int rgb = 0; for (row = 0; row < rows; row++) { data = image.getRowValues(row); for (col = 0; col < cols; col++) { if (data[col] != noData) { z = data[col]; r = (int) data[col] & 0xFF; g = ((int) data[col] >> 8) & 0xFF; b = ((int) data[col] >> 16) & 0xFF; a = ((int) data[col] >> 24) & 0xFF; hsbvals = Color.RGBtoHSB(r, g, b, null); v = hsbvals[2]; binNum = (int) ((v - minValue) / binSize); if (binNum > numBinsLessOne) { binNum = numBinsLessOne; } val = (float) ((cdf[binNum] - cdf[0]) / (numCells - cdf[0])); rgb = Color.HSBtoRGB(hsbvals[0], hsbvals[1], val); r = (rgb >> 16) & 0xFF; g = (rgb >> 8) & 0xFF; b = rgb & 0xFF; z = (double) ((a << 24) | (b << 16) | (g << 8) | r); output.setValue(row, col, z); } } if (cancelOp) { cancelOperation(); return; } progress = (float) (100f * row / (rows - 1)); updateProgress("Loop 3 of 3:", (int) progress); } } output.addMetadataEntry("Created by the " + getDescriptiveName() + " tool."); output.addMetadataEntry("Created on " + new Date()); image.close(); output.close(); // returning a header file string displays the image. returnData(outputHeader); } } catch (OutOfMemoryError oe) { myHost.showFeedback("An out-of-memory error has occurred during operation."); } catch (Exception e) { myHost.showFeedback("An error has occurred during operation. See log file for details."); myHost.logException("Error in " + getDescriptiveName(), e); } finally { updateProgress("Progress: ", 0); // tells the main application that this process is completed. amIActive = false; myHost.pluginComplete(); } } }