- Changed threshold up from >= to >

lessthanoptimal · Jun 27, 2015 · 07917c8 · 07917c8
1 parent 1f90aa9
commit 07917c8
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Showing 4 changed files with 61 additions and 54 deletions.
diff --git a/main/ip/generate/boofcv/alg/filter/binary/GenerateThresholdImageOps.java b/main/ip/generate/boofcv/alg/filter/binary/GenerateThresholdImageOps.java
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2011-2013, Peter Abeles. All Rights Reserved.
+ * Copyright (c) 2011-2015, Peter Abeles. All Rights Reserved.
  *
  * This file is part of BoofCV (http://boofcv.org).
  *
@@ -81,13 +81,13 @@ public void printAdaptive( AutoTypeImage imageIn ) {
 	public void printThreshold( AutoTypeImage imageIn ) {
 		out.print("\t/**\n" +
 				"\t * Applies a global threshold across the whole image.  If 'down' is true, then pixels with values <=\n" +
-				"\t * to 'threshold' are set to 1 and the others set to 0.  If 'down' is false, then pixels with values >=\n" +
+				"\t * to 'threshold' are set to 1 and the others set to 0.  If 'down' is false, then pixels with values >\n" +
 				"\t * to 'threshold' are set to 1 and the others set to 0.\n" +
 				"\t *\n" +
 				"\t * @param input Input image. Not modified.\n" +
 				"\t * @param output (Optional) Binary output image. If null a new image will be declared. Modified.\n" +
 				"\t * @param threshold threshold value.\n" +
-				"\t * @param down If true then the inequality <= is used, otherwise if false then >= is used.\n" +
+				"\t * @param down If true then the inequality <= is used, otherwise if false then > is used.\n" +
 				"\t * @return Output image.\n" +
 				"\t */\n" +
 				"\tpublic static ImageUInt8 threshold( "+imageIn.getSingleBandName()+" input , ImageUInt8 output ,\n" +
@@ -117,7 +117,7 @@ public void printThreshold( AutoTypeImage imageIn ) {
 				"\t\t\t\tint end = indexIn + input.width;\n" +
 				"\n" +
 				"\t\t\t\tfor( ; indexIn < end; indexIn++ , indexOut++ ) {\n" +
-				"\t\t\t\t\tif( (input.data[indexIn]"+imageIn.getBitWise()+") >= threshold )\n" +
+				"\t\t\t\t\tif( (input.data[indexIn]"+imageIn.getBitWise()+") > threshold )\n" +
 				"\t\t\t\t\t\toutput.data[indexOut] = 1;\n" +
 				"\t\t\t\t\telse\n" +
 				"\t\t\t\t\t\toutput.data[indexOut] = 0;\n" +
@@ -139,7 +139,7 @@ public void printAdaptiveSquare( AutoTypeImage imageIn ) {
 				"\t * Thresholds the image using an adaptive threshold that is computed using a local square region centered\n" +
 				"\t * on each pixel.  The threshold is equal to the average value of the surrounding pixels plus the bias.\n" +
 				"\t * If down is true then b(x,y) = I(x,y) <= T(x,y) + bias ? 1 : 0.  Otherwise\n" +
-				"\t * b(x,y) = I(x,y) >= T(x,y) + bias ? 0 : 1\n" +
+				"\t * b(x,y) = I(x,y) > T(x,y) + bias ? 0 : 1\n" +
 				"\t *\n" +
 				"\t * @param input Input image.\n" +
 				"\t * @param output (optional) Output binary image.  If null it will be declared internally.\n" +
@@ -190,7 +190,7 @@ public void printAdaptiveSquare( AutoTypeImage imageIn ) {
 				"\t\t\t\tfor( ; indexIn < end; indexIn++ , indexOut++, indexMean++ ) {\n" +
 				"\t\t\t\t\t"+sumType+" threshold = (mean.data[indexMean]"+bitwise+") + bias;\n" +
 				"\n" +
-				"\t\t\t\t\tif( (input.data[indexIn]"+bitwise+") >= threshold )\n" +
+				"\t\t\t\t\tif( (input.data[indexIn]"+bitwise+") > threshold )\n" +
 				"\t\t\t\t\t\toutput.data[indexOut] = 1;\n" +
 				"\t\t\t\t\telse\n" +
 				"\t\t\t\t\t\toutput.data[indexOut] = 0;\n" +
@@ -212,7 +212,7 @@ public void printAdaptiveGaussian( AutoTypeImage imageIn ) {
 				"\t * Thresholds the image using an adaptive threshold that is computed using a local square region centered\n" +
 				"\t * on each pixel.  The threshold is equal to the gaussian weighted sum of the surrounding pixels plus the bias.\n" +
 				"\t * If down is true then b(x,y) = I(x,y) <= T(x,y) + bias ? 1 : 0.  Otherwise\n" +
-				"\t * b(x,y) = I(x,y) >= T(x,y) + bias ? 0 : 1\n" +
+				"\t * b(x,y) = I(x,y) > T(x,y) + bias ? 0 : 1\n" +
 				"\t *\n" +
 				"\t * @param input Input image.\n" +
 				"\t * @param output (optional) Output binary image.  If null it will be declared internally.\n" +
@@ -263,7 +263,7 @@ public void printAdaptiveGaussian( AutoTypeImage imageIn ) {
 				"\t\t\t\tfor( ; indexIn < end; indexIn++ , indexOut++, indexMean++ ) {\n" +
 				"\t\t\t\t\t"+sumType+" threshold = (blur.data[indexMean]"+bitwise+") + bias;\n" +
 				"\n" +
-				"\t\t\t\t\tif( (input.data[indexIn]"+bitwise+") >= threshold )\n" +
+				"\t\t\t\t\tif( (input.data[indexIn]"+bitwise+") > threshold )\n" +
 				"\t\t\t\t\t\toutput.data[indexOut] = 1;\n" +
 				"\t\t\t\t\telse\n" +
 				"\t\t\t\t\t\toutput.data[indexOut] = 0;\n" +

diff --git a/main/ip/src/boofcv/alg/filter/binary/GThresholdImageOps.java b/main/ip/src/boofcv/alg/filter/binary/GThresholdImageOps.java
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2011-2014, Peter Abeles. All Rights Reserved.
+ * Copyright (c) 2011-2015, Peter Abeles. All Rights Reserved.
  *
  * This file is part of BoofCV (http://boofcv.org).
  *
@@ -66,11 +66,14 @@ public static int computeOtsu( ImageSingleBand input , int minValue , int maxVal
 	 */
 	// original code from http://www.labbookpages.co.uk/software/imgProc/otsuThreshold.html
 	//                    Dr. Andrew Greensted
+	// modifications to reduce overflow
 	public static int computeOtsu( int histogram[] , int length , int totalPixels ) {
 
+		double dlength = length;
 		double sum = 0;
 		for (int i=0 ; i< length ; i++)
-			sum += i*histogram[i];
+			sum += (i/dlength)*histogram[i];
+
 
 		double sumB = 0;
 		int wB = 0;
@@ -85,7 +88,7 @@ public static int computeOtsu( int histogram[] , int length , int totalPixels )
 			int wF = totalPixels - wB;         // Weight Foreground
 			if (wF == 0) break;
 
-			sumB += i*histogram[i];
+			sumB += (i/dlength)*histogram[i];
 
 			double mB = sumB / wB;            // Mean Background
 			double mF = (sum - sumB) / wF;    // Mean Foreground
@@ -197,13 +200,13 @@ public static int computeEntropy( int histogram[] , int length , int totalPixels
 
 	/**
 	 * Applies a global threshold across the whole image.  If 'down' is true, then pixels with values <=
-	 * to 'threshold' are set to 1 and the others set to 0.  If 'down' is false, then pixels with values >=
+	 * to 'threshold' are set to 1 and the others set to 0.  If 'down' is false, then pixels with values >
 	 * to 'threshold' are set to 1 and the others set to 0.
 	 *
 	 * @param input Input image. Not modified.
 	 * @param output (Optional) Binary output image. If null a new image will be declared. Modified.
 	 * @param threshold threshold value.
-	 * @param down If true then the inequality <= is used, otherwise if false then >= is used.
+	 * @param down If true then the inequality <= is used, otherwise if false then > is used.
 	 * @return binary image.
 	 */
 	public static <T extends ImageSingleBand>
@@ -232,7 +235,7 @@ ImageUInt8 threshold( T input , ImageUInt8 output ,
 	 * Thresholds the image using an adaptive threshold that is computed using a local square region centered
 	 * on each pixel.  The threshold is equal to the average value of the surrounding pixels plus the bias.
 	 * If down is true then b(x,y) = I(x,y) <= T(x,y) + bias ? 1 : 0.  Otherwise
-	 * b(x,y) = I(x,y) >= T(x,y) + bias ? 0 : 1
+	 * b(x,y) = I(x,y) > T(x,y) + bias ? 0 : 1
 	 * </p>
 	 *
 	 * <p>
@@ -269,7 +272,7 @@ ImageUInt8 adaptiveSquare( T input , ImageUInt8 output ,
 	 * Thresholds the image using an adaptive threshold that is computed using a local square region centered
 	 * on each pixel.  The threshold is equal to the gaussian weighted sum of the surrounding pixels plus the bias.
 	 * If down is true then b(x,y) = I(x,y) <= T(x,y) + bias ? 1 : 0.  Otherwise
-	 * b(x,y) = I(x,y) >= T(x,y) + bias ? 0 : 1
+	 * b(x,y) = I(x,y) > T(x,y) + bias ? 0 : 1
 	 * </p>
 	 *
 	 * <p>

diff --git a/main/ip/src/boofcv/alg/filter/binary/ThresholdImageOps.java b/main/ip/src/boofcv/alg/filter/binary/ThresholdImageOps.java
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2011-2014, Peter Abeles. All Rights Reserved.
+ * Copyright (c) 2011-2015, Peter Abeles. All Rights Reserved.
  *
  * This file is part of BoofCV (http://boofcv.org).
  *
@@ -15,7 +15,6 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
-
 package boofcv.alg.filter.binary;
 
 import boofcv.alg.InputSanityCheck;
@@ -37,13 +36,13 @@ public class ThresholdImageOps {
 
 	/**
 	 * Applies a global threshold across the whole image.  If 'down' is true, then pixels with values <=
-	 * to 'threshold' are set to 1 and the others set to 0.  If 'down' is false, then pixels with values >=
+	 * to 'threshold' are set to 1 and the others set to 0.  If 'down' is false, then pixels with values >
 	 * to 'threshold' are set to 1 and the others set to 0.
 	 *
 	 * @param input Input image. Not modified.
-	 * @param output Binary output image. If null a new image will be declared. Modified.
+	 * @param output (Optional) Binary output image. If null a new image will be declared. Modified.
 	 * @param threshold threshold value.
-	 * @param down If true then the inequality <= is used, otherwise if false then >= is used.
+	 * @param down If true then the inequality <= is used, otherwise if false then > is used.
 	 * @return Output image.
 	 */
 	public static ImageUInt8 threshold( ImageFloat32 input , ImageUInt8 output ,
@@ -73,7 +72,7 @@ public static ImageUInt8 threshold( ImageFloat32 input , ImageUInt8 output ,
 				int end = indexIn + input.width;
 
 				for( ; indexIn < end; indexIn++ , indexOut++ ) {
-					if( (input.data[indexIn]) >= threshold )
+					if( (input.data[indexIn]) > threshold )
 						output.data[indexOut] = 1;
 					else
 						output.data[indexOut] = 0;
@@ -86,13 +85,13 @@ public static ImageUInt8 threshold( ImageFloat32 input , ImageUInt8 output ,
 
 	/**
 	 * Applies a global threshold across the whole image.  If 'down' is true, then pixels with values <=
-	 * to 'threshold' are set to 1 and the others set to 0.  If 'down' is false, then pixels with values >=
+	 * to 'threshold' are set to 1 and the others set to 0.  If 'down' is false, then pixels with values >
 	 * to 'threshold' are set to 1 and the others set to 0.
 	 *
 	 * @param input Input image. Not modified.
-	 * @param output Binary output image. If null a new image will be declared. Modified.
+	 * @param output (Optional) Binary output image. If null a new image will be declared. Modified.
 	 * @param threshold threshold value.
-	 * @param down If true then the inequality <= is used, otherwise if false then >= is used.
+	 * @param down If true then the inequality <= is used, otherwise if false then > is used.
 	 * @return Output image.
 	 */
 	public static ImageUInt8 threshold( ImageFloat64 input , ImageUInt8 output ,
@@ -122,7 +121,7 @@ public static ImageUInt8 threshold( ImageFloat64 input , ImageUInt8 output ,
 				int end = indexIn + input.width;
 
 				for( ; indexIn < end; indexIn++ , indexOut++ ) {
-					if( (input.data[indexIn]) >= threshold )
+					if( (input.data[indexIn]) > threshold )
 						output.data[indexOut] = 1;
 					else
 						output.data[indexOut] = 0;
@@ -135,13 +134,13 @@ public static ImageUInt8 threshold( ImageFloat64 input , ImageUInt8 output ,
 
 	/**
 	 * Applies a global threshold across the whole image.  If 'down' is true, then pixels with values <=
-	 * to 'threshold' are set to 1 and the others set to 0.  If 'down' is false, then pixels with values >=
+	 * to 'threshold' are set to 1 and the others set to 0.  If 'down' is false, then pixels with values >
 	 * to 'threshold' are set to 1 and the others set to 0.
 	 *
 	 * @param input Input image. Not modified.
-	 * @param output Binary output image. If null a new image will be declared. Modified.
+	 * @param output (Optional) Binary output image. If null a new image will be declared. Modified.
 	 * @param threshold threshold value.
-	 * @param down If true then the inequality <= is used, otherwise if false then >= is used.
+	 * @param down If true then the inequality <= is used, otherwise if false then > is used.
 	 * @return Output image.
 	 */
 	public static ImageUInt8 threshold( ImageUInt8 input , ImageUInt8 output ,
@@ -171,7 +170,7 @@ public static ImageUInt8 threshold( ImageUInt8 input , ImageUInt8 output ,
 				int end = indexIn + input.width;
 
 				for( ; indexIn < end; indexIn++ , indexOut++ ) {
-					if( (input.data[indexIn]& 0xFF) >= threshold )
+					if( (input.data[indexIn]& 0xFF) > threshold )
 						output.data[indexOut] = 1;
 					else
 						output.data[indexOut] = 0;
@@ -184,13 +183,13 @@ public static ImageUInt8 threshold( ImageUInt8 input , ImageUInt8 output ,
 
 	/**
 	 * Applies a global threshold across the whole image.  If 'down' is true, then pixels with values <=
-	 * to 'threshold' are set to 1 and the others set to 0.  If 'down' is false, then pixels with values >=
+	 * to 'threshold' are set to 1 and the others set to 0.  If 'down' is false, then pixels with values >
 	 * to 'threshold' are set to 1 and the others set to 0.
 	 *
 	 * @param input Input image. Not modified.
-	 * @param output Binary output image. If null a new image will be declared. Modified.
+	 * @param output (Optional) Binary output image. If null a new image will be declared. Modified.
 	 * @param threshold threshold value.
-	 * @param down If true then the inequality <= is used, otherwise if false then >= is used.
+	 * @param down If true then the inequality <= is used, otherwise if false then > is used.
 	 * @return Output image.
 	 */
 	public static ImageUInt8 threshold( ImageSInt16 input , ImageUInt8 output ,
@@ -220,7 +219,7 @@ public static ImageUInt8 threshold( ImageSInt16 input , ImageUInt8 output ,
 				int end = indexIn + input.width;
 
 				for( ; indexIn < end; indexIn++ , indexOut++ ) {
-					if( (input.data[indexIn]) >= threshold )
+					if( (input.data[indexIn]) > threshold )
 						output.data[indexOut] = 1;
 					else
 						output.data[indexOut] = 0;
@@ -233,13 +232,13 @@ public static ImageUInt8 threshold( ImageSInt16 input , ImageUInt8 output ,
 
 	/**
 	 * Applies a global threshold across the whole image.  If 'down' is true, then pixels with values <=
-	 * to 'threshold' are set to 1 and the others set to 0.  If 'down' is false, then pixels with values >=
+	 * to 'threshold' are set to 1 and the others set to 0.  If 'down' is false, then pixels with values >
 	 * to 'threshold' are set to 1 and the others set to 0.
 	 *
 	 * @param input Input image. Not modified.
-	 * @param output Binary output image. If null a new image will be declared. Modified.
+	 * @param output (Optional) Binary output image. If null a new image will be declared. Modified.
 	 * @param threshold threshold value.
-	 * @param down If true then the inequality <= is used, otherwise if false then >= is used.
+	 * @param down If true then the inequality <= is used, otherwise if false then > is used.
 	 * @return Output image.
 	 */
 	public static ImageUInt8 threshold( ImageUInt16 input , ImageUInt8 output ,
@@ -269,7 +268,7 @@ public static ImageUInt8 threshold( ImageUInt16 input , ImageUInt8 output ,
 				int end = indexIn + input.width;
 
 				for( ; indexIn < end; indexIn++ , indexOut++ ) {
-					if( (input.data[indexIn]& 0xFFFF) >= threshold )
+					if( (input.data[indexIn]& 0xFFFF) > threshold )
 						output.data[indexOut] = 1;
 					else
 						output.data[indexOut] = 0;
@@ -282,13 +281,13 @@ public static ImageUInt8 threshold( ImageUInt16 input , ImageUInt8 output ,
 
 	/**
 	 * Applies a global threshold across the whole image.  If 'down' is true, then pixels with values <=
-	 * to 'threshold' are set to 1 and the others set to 0.  If 'down' is false, then pixels with values >=
+	 * to 'threshold' are set to 1 and the others set to 0.  If 'down' is false, then pixels with values >
 	 * to 'threshold' are set to 1 and the others set to 0.
 	 *
 	 * @param input Input image. Not modified.
-	 * @param output Binary output image. If null a new image will be declared. Modified.
+	 * @param output (Optional) Binary output image. If null a new image will be declared. Modified.
 	 * @param threshold threshold value.
-	 * @param down If true then the inequality <= is used, otherwise if false then >= is used.
+	 * @param down If true then the inequality <= is used, otherwise if false then > is used.
 	 * @return Output image.
 	 */
 	public static ImageUInt8 threshold( ImageSInt32 input , ImageUInt8 output ,
@@ -318,7 +317,7 @@ public static ImageUInt8 threshold( ImageSInt32 input , ImageUInt8 output ,
 				int end = indexIn + input.width;
 
 				for( ; indexIn < end; indexIn++ , indexOut++ ) {
-					if( (input.data[indexIn]) >= threshold )
+					if( (input.data[indexIn]) > threshold )
 						output.data[indexOut] = 1;
 					else
 						output.data[indexOut] = 0;
@@ -333,7 +332,7 @@ public static ImageUInt8 threshold( ImageSInt32 input , ImageUInt8 output ,
 	 * Thresholds the image using an adaptive threshold that is computed using a local square region centered
 	 * on each pixel.  The threshold is equal to the average value of the surrounding pixels plus the bias.
 	 * If down is true then b(x,y) = I(x,y) <= T(x,y) + bias ? 1 : 0.  Otherwise
-	 * b(x,y) = I(x,y) >= T(x,y) + bias ? 0 : 1
+	 * b(x,y) = I(x,y) > T(x,y) + bias ? 0 : 1
 	 *
 	 * @param input Input image.
 	 * @param output (optional) Output binary image.  If null it will be declared internally.
@@ -384,7 +383,7 @@ public static ImageUInt8 adaptiveSquare( ImageUInt8 input , ImageUInt8 output ,
 				for( ; indexIn < end; indexIn++ , indexOut++, indexMean++ ) {
 					int threshold = (mean.data[indexMean]& 0xFF) + bias;
 
-					if( (input.data[indexIn]& 0xFF) >= threshold )
+					if( (input.data[indexIn]& 0xFF) > threshold )
 						output.data[indexOut] = 1;
 					else
 						output.data[indexOut] = 0;
@@ -399,7 +398,7 @@ public static ImageUInt8 adaptiveSquare( ImageUInt8 input , ImageUInt8 output ,
 	 * Thresholds the image using an adaptive threshold that is computed using a local square region centered
 	 * on each pixel.  The threshold is equal to the gaussian weighted sum of the surrounding pixels plus the bias.
 	 * If down is true then b(x,y) = I(x,y) <= T(x,y) + bias ? 1 : 0.  Otherwise
-	 * b(x,y) = I(x,y) >= T(x,y) + bias ? 0 : 1
+	 * b(x,y) = I(x,y) > T(x,y) + bias ? 0 : 1
 	 *
 	 * @param input Input image.
 	 * @param output (optional) Output binary image.  If null it will be declared internally.
@@ -450,7 +449,7 @@ public static ImageUInt8 adaptiveGaussian( ImageUInt8 input , ImageUInt8 output
 				for( ; indexIn < end; indexIn++ , indexOut++, indexMean++ ) {
 					int threshold = (blur.data[indexMean]& 0xFF) + bias;
 
-					if( (input.data[indexIn]& 0xFF) >= threshold )
+					if( (input.data[indexIn]& 0xFF) > threshold )
 						output.data[indexOut] = 1;
 					else
 						output.data[indexOut] = 0;
@@ -465,7 +464,7 @@ public static ImageUInt8 adaptiveGaussian( ImageUInt8 input , ImageUInt8 output
 	 * Thresholds the image using an adaptive threshold that is computed using a local square region centered
 	 * on each pixel.  The threshold is equal to the average value of the surrounding pixels plus the bias.
 	 * If down is true then b(x,y) = I(x,y) <= T(x,y) + bias ? 1 : 0.  Otherwise
-	 * b(x,y) = I(x,y) >= T(x,y) + bias ? 0 : 1
+	 * b(x,y) = I(x,y) > T(x,y) + bias ? 0 : 1
 	 *
 	 * @param input Input image.
 	 * @param output (optional) Output binary image.  If null it will be declared internally.
@@ -516,7 +515,7 @@ public static ImageUInt8 adaptiveSquare( ImageFloat32 input , ImageUInt8 output
 				for( ; indexIn < end; indexIn++ , indexOut++, indexMean++ ) {
 					float threshold = (mean.data[indexMean]) + bias;
 
-					if( (input.data[indexIn]) >= threshold )
+					if( (input.data[indexIn]) > threshold )
 						output.data[indexOut] = 1;
 					else
 						output.data[indexOut] = 0;
@@ -531,7 +530,7 @@ public static ImageUInt8 adaptiveSquare( ImageFloat32 input , ImageUInt8 output
 	 * Thresholds the image using an adaptive threshold that is computed using a local square region centered
 	 * on each pixel.  The threshold is equal to the gaussian weighted sum of the surrounding pixels plus the bias.
 	 * If down is true then b(x,y) = I(x,y) <= T(x,y) + bias ? 1 : 0.  Otherwise
-	 * b(x,y) = I(x,y) >= T(x,y) + bias ? 0 : 1
+	 * b(x,y) = I(x,y) > T(x,y) + bias ? 0 : 1
 	 *
 	 * @param input Input image.
 	 * @param output (optional) Output binary image.  If null it will be declared internally.
@@ -582,7 +581,7 @@ public static ImageUInt8 adaptiveGaussian( ImageFloat32 input , ImageUInt8 outpu
 				for( ; indexIn < end; indexIn++ , indexOut++, indexMean++ ) {
 					float threshold = (blur.data[indexMean]) + bias;
 
-					if( (input.data[indexIn]) >= threshold )
+					if( (input.data[indexIn]) > threshold )
 						output.data[indexOut] = 1;
 					else
 						output.data[indexOut] = 0;