Import all sources from perforce.

src/nvimage/Filter.h

@@ -0,0 +1,103 @@
+// This code is in the public domain -- castanyo@yahoo.es
+
+#ifndef NV_IMAGE_FILTER_H
+#define NV_IMAGE_FILTER_H
+
+#include <nvimage/nvimage.h>
+
+namespace nv
+{
+	class Vector4;
+
+	/// A filter function.
+	struct Filter 
+	{
+		// Standard filters.
+		enum Enum 
+		{
+			Box,
+			Triangle,
+			Quadratic,	// Bell
+			Cubic,
+			Spline,
+			Lanczos,
+			Mitchell,
+			Kaiser,
+			Num
+		};
+
+		float (*function)(float x);
+		float support;
+	};
+
+
+	/// A 1D kernel. Used to precompute filter weights.
+	class Kernel1
+	{
+	public:
+		NVIMAGE_API Kernel1(uint width);
+		NVIMAGE_API Kernel1(const Kernel1 & k);
+		NVIMAGE_API ~Kernel1();
+		
+		NVIMAGE_API void normalize();
+		
+		float valueAt(uint x) const {
+			return data[x];
+		}
+		
+		uint width() const {
+			return w;
+		}
+		
+		NVIMAGE_API void initFilter(Filter::Enum filter);
+		NVIMAGE_API void initSinc(float stretch = 1);
+		NVIMAGE_API void initKaiser(float alpha = 4.0f, float stretch = 1.0f);
+		NVIMAGE_API void initMitchell(float b = 1.0f/3.0f, float c = 1.0f/3.0f);
+		
+		NVIMAGE_API void debugPrint();
+		
+	private:
+		const uint w;
+		float * data;
+	};
+
+
+	/// A 2D kernel.
+	class Kernel2 
+	{
+	public:
+		NVIMAGE_API Kernel2(uint width);
+		NVIMAGE_API Kernel2(const Kernel2 & k);
+		NVIMAGE_API ~Kernel2();
+		
+		NVIMAGE_API void normalize();
+		NVIMAGE_API void transpose();
+		
+		float valueAt(uint x, uint y) const {
+			return data[y * w + x];
+		}
+		
+		uint width() const {
+			return w;
+		}
+		
+		NVIMAGE_API void initLaplacian();
+		NVIMAGE_API void initEdgeDetection();
+		NVIMAGE_API void initSobel();
+		NVIMAGE_API void initPrewitt();
+
+		NVIMAGE_API void initBlendedSobel(const Vector4 & scale);
+
+	private:
+		const uint w;
+		float * data;
+	};
+
+
+	// @@ Implement non linear filters:
+	// Kuwahara filter
+	// Median filter
+
+} // nv namespace
+
+#endif // NV_IMAGE_FILTER_H