Initial source commit

minorGems/graphics/test/rgb2yiq.cpp

@@ -0,0 +1,149 @@
+/*
+ * Modification History
+ *
+ * 2001-September-19		Jason Rohrer
+ * Created.
+ *
+ * 2001-September-20		Jason Rohrer
+ * Finished initial implementation.
+ * Changed so that images are normalized to [0,1] before
+ * being output.
+ */
+
+#include "minorGems/graphics/Image.h"
+#include "minorGems/graphics/ImageColorConverter.h"
+
+#include "minorGems/graphics/converters/BMPImageConverter.h"
+
+#include "minorGems/io/file/File.h"
+#include "minorGems/io/file/FileInputStream.h"
+#include "minorGems/io/file/FileOutputStream.h"
+
+#include <stdio.h>
+#include <stdlib.h>
+
+
+
+void usage( char *inAppName );
+Image *loadBMPImage( char *inFileName );
+void writeBMPImage( char *inFileName, Image *inImage );
+
+// normalizes an image into the pixel range [0,1] if some
+// pixels are out of range
+void normalizeImage( Image *inImage );
+
+
+
+// a test program that converts an rgb BMP to a yiq BMP
+int main( char inNumArgs, char **inArgs ) {
+
+	if( inNumArgs != 3 ) {
+		usage( inArgs[0] );
+		}
+
+	Image *rgbImage = loadBMPImage( inArgs[1] );
+
+	Image *yiqImage = ImageColorConverter::RGBToYIQ( rgbImage );
+
+	normalizeImage( yiqImage );
+
+	
+	writeBMPImage( inArgs[2], yiqImage );
+
+	delete rgbImage;
+	delete yiqImage;
+	
+	return 0;
+	}
+
+
+void usage( char *inAppName ) {
+	printf( "Usage:\n" );
+	printf( "\t%s rgb_image_bmp yiq_image_bmp\n", inAppName );
+	printf( "Example:\n" );
+	printf( "\t%s testRGB.bmp testYIQ.bmp\n", inAppName );
+	
+	exit( 1 );
+	}
+
+
+
+void normalizeImage( Image *inImage ) {
+	// now normalize the image so that pixels are in the range [0,1]
+	
+	int numPixels = inImage->getWidth() * inImage->getHeight();
+	int numChannels = inImage->getNumChannels();
+	double minValue = 1000.0;
+	double maxValue = -1000.0;
+	int c;
+
+	// search for min and max values
+	for( c=0; c<numChannels; c++ ) {
+		double *channel = inImage->getChannel( c );
+		for( int p=0; p<numPixels; p++ ) {
+			if( channel[p] < minValue ) {
+				minValue = channel[p];
+				}
+			else if( channel[p] > maxValue ) {
+				maxValue = channel[p];
+				}
+			}
+		}
+
+	double diff = maxValue - minValue;
+
+	if( minValue >= 0 && diff + minValue <= 1 ) {
+		// no need to normalize, as values are already
+		// in range
+		return;
+		}
+	
+	double scale = 1.0 / diff;
+
+	// now normalize all pixels
+	for( c=0; c<numChannels; c++ ) {
+		double *channel = inImage->getChannel( c );
+		for( int p=0; p<numPixels; p++ ) {
+			channel[p] = ( channel[p] - minValue ) * scale;
+			}
+		}
+	}
+
+
+
+Image *loadBMPImage( char *inFileName ) {
+	File *imageFile = new File( NULL, inFileName,
+									  strlen( inFileName ) );
+	FileInputStream *imageStream
+		= new FileInputStream( imageFile );
+
+	BMPImageConverter *converter = new BMPImageConverter();
+
+	Image *returnImage = converter->deformatImage( imageStream );
+
+	delete imageFile;
+	delete imageStream;
+	delete converter;
+
+	return returnImage;
+	}
+
+
+
+void writeBMPImage( char *inFileName, Image *inImage ) {
+	File *imageFile = new File( NULL, inFileName,
+									  strlen( inFileName ) );
+	FileOutputStream *imageStream
+		= new FileOutputStream( imageFile );
+
+	BMPImageConverter *converter = new BMPImageConverter();
+
+	converter->formatImage( inImage, imageStream );
+
+	delete imageFile;
+	delete imageStream;
+	delete converter;
+	}
+
+
+