/*
* 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.util.Date;
import whitebox.geospatialfiles.WhiteboxRaster;
import whitebox.interfaces.WhiteboxPlugin;
import whitebox.interfaces.WhiteboxPluginHost;
/**
* This tool can be used to perform a difference-of-Gaussians filter on a raster image. which involves the subtraction of one smoothed version of an image from another less smoothed version of the image.
* @author Dr. John Lindsay email: jlindsay@uoguelph.ca
*/
public class FilterDoG 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 "FilterDoG";
}
/**
* 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 "Difference-of-Gaussians Filter";
}
/**
* 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 Difference-of-Gaussians filter 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 = { "Filters" };
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 inputHeader = null;
String outputHeader = null;
int row, col, x, y;
double z;
float progress = 0;
int a;
int filterSize1 = 3;
int filterSize2 = 3;
double n;
double sum;
int[] dX1;
int[] dX2;
int[] dY1;
int[] dY2;
double[] weights1;
double[] weights2;
int midPoint;
int numPixelsInFilter1;
int numPixelsInFilter2;
boolean reflectAtBorders = false;
double sigma1 = 0;
double sigma2 = 0;
double recipRoot2PiTimesSigma1;
double recipRoot2PiTimesSigma2;
double twoSigmaSqr1;
double twoSigmaSqr2;
double zN, zFinal_1, zFinal_2;
if (args.length <= 0) {
showFeedback("Plugin parameters have not been set.");
return;
}
for (int i = 0; i < args.length; i++) {
if (i == 0) {
inputHeader = args[i];
} else if (i == 1) {
outputHeader = args[i];
} else if (i == 2) {
sigma1 = Double.parseDouble(args[i]);
} else if (i == 3) {
sigma2 = Double.parseDouble(args[i]);
} else if (i == 4) {
reflectAtBorders = Boolean.parseBoolean(args[i]);
}
}
if (sigma1 < 0.5) {
sigma1 = 0.5;
} else if (sigma1 > 20) {
sigma1 = 20;
}
if (sigma2 < 0.5) {
sigma2 = 0.5;
} else if (sigma2 > 20) {
sigma2 = 20;
}
if (sigma1 == sigma2) {
showFeedback("The two standard deviations cannot be equal.");
return;
}
// check to see that the inputHeader and outputHeader are not null.
if ((inputHeader == null) || (outputHeader == null)) {
showFeedback("One or more of the input parameters have not been set properly.");
return;
}
try {
WhiteboxRaster inputFile = new WhiteboxRaster(inputHeader, "r");
inputFile.isReflectedAtEdges = reflectAtBorders;
int rows = inputFile.getNumberRows();
int cols = inputFile.getNumberColumns();
double noData = inputFile.getNoDataValue();
WhiteboxRaster outputFile = new WhiteboxRaster(outputHeader, "rw", inputHeader, WhiteboxRaster.DataType.FLOAT, noData);
outputFile.setPreferredPalette("grey.pal");
recipRoot2PiTimesSigma1 = 1 / (Math.sqrt(2 * Math.PI) * sigma1);
twoSigmaSqr1 = 2 * sigma1 * sigma1;
recipRoot2PiTimesSigma2 = 1 / (Math.sqrt(2 * Math.PI) * sigma2);
twoSigmaSqr2 = 2 * sigma2 * sigma2;
//figure out the size of the filter
double weight;
for (int i = 0; i <= 250; i++) {
weight = recipRoot2PiTimesSigma1 * Math.exp(-1 * (i * i) / twoSigmaSqr1);
if (weight <= 0.001) {
filterSize1 = i * 2 + 1;
break;
}
}
//the filter dimensions must be odd numbers such that there is a middle pixel
if (filterSize1 % 2 == 0) {
filterSize1++;
}
if (filterSize1 < 3) { filterSize1 = 3; }
numPixelsInFilter1 = filterSize1 * filterSize1;
dX1 = new int[numPixelsInFilter1];
dY1 = new int[numPixelsInFilter1];
weights1 = new double[numPixelsInFilter1];
//fill the filter DX and DY values and the distance-weights
midPoint = (int)Math.floor(filterSize1 / 2) + 1;
a = 0;
for (row = 0; row < filterSize1; row++) {
for (col = 0; col < filterSize1; col++) {
x = col - midPoint;
y = row - midPoint;
dX1[a] = x;
dY1[a] = y;
weight = recipRoot2PiTimesSigma1 * Math.exp(-1 * (x * x + y * y) / twoSigmaSqr1);
weights1[a] = weight;
a++;
}
}
//figure out the size of the filter
for (int i = 0; i <= 250; i++) {
weight = recipRoot2PiTimesSigma2 * Math.exp(-1 * (i * i) / twoSigmaSqr2);
if (weight <= 0.001) {
filterSize2 = i * 2 + 1;
break;
}
}
//the filter dimensions must be odd numbers such that there is a middle pixel
if (filterSize2 % 2 == 0) {
filterSize2++;
}
if (filterSize2 < 3) { filterSize2 = 3; }
numPixelsInFilter2 = filterSize2 * filterSize2;
dX2 = new int[numPixelsInFilter2];
dY2 = new int[numPixelsInFilter2];
weights2 = new double[numPixelsInFilter2];
//fill the filter DX and DY values and the distance-weights
midPoint = (int)Math.floor(filterSize2 / 2) + 1;
a = 0;
for (row = 0; row < filterSize2; row++) {
for (col = 0; col < filterSize2; col++) {
x = col - midPoint;
y = row - midPoint;
dX2[a] = x;
dY2[a] = y;
weight = recipRoot2PiTimesSigma2 * Math.exp(-1 * (x * x + y * y) / twoSigmaSqr2);
weights2[a] = weight;
a++;
}
}
for (row = 0; row < rows; row++) {
for (col = 0; col < cols; col++) {
z = inputFile.getValue(row, col);
if (z != noData) {
sum = 0;
zFinal_1 = 0;
for (a = 0; a < numPixelsInFilter1; a++) {
x = col + dX1[a];
y = row + dY1[a];
zN = inputFile.getValue(y, x);
if (zN != noData) {
sum += weights1[a];
zFinal_1 += weights1[a] * zN;
}
}
zFinal_1 = zFinal_1 / sum;
sum = 0;
zFinal_2 = 0;
for (a = 0; a < numPixelsInFilter2; a++) {
x = col + dX2[a];
y = row + dY2[a];
zN = inputFile.getValue(y, x);
if (zN != noData) {
sum += weights2[a];
zFinal_2 += weights2[a] * zN;
}
}
zFinal_2 = zFinal_2 / sum;
outputFile.setValue(row, col, zFinal_1 - zFinal_2);
} else {
outputFile.setValue(row, col, noData);
}
}
if (cancelOp) {
cancelOperation();
return;
}
progress = (float) (100f * row / (rows - 1));
updateProgress((int) progress);
}
outputFile.addMetadataEntry("Created by the "
+ getDescriptiveName() + " tool.");
outputFile.addMetadataEntry("Created on " + new Date());
inputFile.close();
outputFile.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();
}
}
}