Cubic Prefilter Patch against 587b2f105c4e14031f4d70c31d12f9d4da7439ca

cubic-prefilter.patch

diff --git a/source/blender/compositor/intern/COM_SocketReader.h b/source/blender/compositor/intern/COM_SocketReader.h
index 88b018ef8b..0563d9e1b0 100644
--- a/source/blender/compositor/intern/COM_SocketReader.h
+++ b/source/blender/compositor/intern/COM_SocketReader.h
@@ -32,7 +32,8 @@
 typedef enum PixelSampler {
 	COM_PS_NEAREST = 0,
 	COM_PS_BILINEAR = 1,
-	COM_PS_BICUBIC = 2
+	COM_PS_BICUBIC = 2,
+	COM_PS_CUBICBSPLINEPREFILTER = 3
 } PixelSampler;
 
 class MemoryBuffer;
diff --git a/source/blender/compositor/operations/COM_ImageOperation.cpp b/source/blender/compositor/operations/COM_ImageOperation.cpp
index fb3efbb67e..459b02afd3 100644
--- a/source/blender/compositor/operations/COM_ImageOperation.cpp
+++ b/source/blender/compositor/operations/COM_ImageOperation.cpp
@@ -40,6 +40,7 @@ BaseImageOperation::BaseImageOperation() : NodeOperation()
 {
 	this->m_image = NULL;
 	this->m_buffer = NULL;
+	this->m_secondaryBuffer = NULL;
 	this->m_imageBuffer = NULL;
 	this->m_imageUser = NULL;
 	this->m_imagewidth = 0;
@@ -80,6 +81,7 @@ ImBuf *BaseImageOperation::getImBuf()
 void BaseImageOperation::initExecution()
 {
 	ImBuf *stackbuf = getImBuf();
+	this->initMutex();
 	this->m_buffer = stackbuf;
 	if (stackbuf) {
 		this->m_imageBuffer = stackbuf->rect_float;
@@ -92,7 +94,12 @@ void BaseImageOperation::initExecution()
 
 void BaseImageOperation::deinitExecution()
 {
+    this->deinitMutex();
 	this->m_imageBuffer = NULL;
+    if (this->m_secondaryBuffer) {
+        IMB_freeImBuf(m_secondaryBuffer);
+        m_secondaryBuffer = NULL;
+    }
 }
 
 void BaseImageOperation::determineResolution(unsigned int resolution[2], unsigned int preferredResolution[2])
@@ -108,6 +115,20 @@ void BaseImageOperation::determineResolution(unsigned int resolution[2], unsigne
 	}
 }
 
+/* Must be located in BaseImageOperation to avoid code duplication */
+void BaseImageOperation::initSecondaryBuffer(int buffer_type)
+{
+    switch (buffer_type) {
+        case BT_DUPLICATE:
+            this->m_secondaryBuffer = IMB_dupImBuf(this->m_buffer);
+            break;
+        case BT_CUBICBSPLINEPREFILTER:
+            this->m_secondaryBuffer = IMB_dupImBuf(this->m_buffer);
+            create_prefilter(this->m_buffer, this->m_secondaryBuffer);
+            break;
+    }
+}
+
 void ImageOperation::executePixel(float output[4], float x, float y, PixelSampler sampler)
 {
 	if (this->m_imageBuffer == NULL || x < 0 || y < 0 || x >= this->getWidth() || y >= this->getHeight() ) {
@@ -124,6 +145,13 @@ void ImageOperation::executePixel(float output[4], float x, float y, PixelSample
 			case COM_PS_BICUBIC:
 				bicubic_interpolation_color(this->m_buffer, NULL, output, x, y);
 				break;
+			case COM_PS_CUBICBSPLINEPREFILTER:
+			    lockMutex();
+			    if (this->m_secondaryBuffer == NULL) {
+			        BaseImageOperation::initSecondaryBuffer(BT_CUBICBSPLINEPREFILTER);
+			    }
+			    unlockMutex();
+			    bicubic_interpolation_color(this->m_secondaryBuffer, NULL, output, x, y);
 		}
 	}
 }
@@ -147,6 +175,13 @@ void ImageAlphaOperation::executePixel(float output[4], float x, float y, PixelS
 			case COM_PS_BICUBIC:
 				bicubic_interpolation_color(this->m_buffer, NULL, tempcolor, x, y);
 				break;
+			case COM_PS_CUBICBSPLINEPREFILTER:
+			    lockMutex();
+			    if (this->m_secondaryBuffer == NULL) {
+			        BaseImageOperation::initSecondaryBuffer(BT_CUBICBSPLINEPREFILTER);
+			    }
+			    unlockMutex();
+			    bicubic_interpolation_color(this->m_secondaryBuffer, NULL, output, x, y);
 		}
 		output[0] = tempcolor[3];
 	}
diff --git a/source/blender/compositor/operations/COM_ImageOperation.h b/source/blender/compositor/operations/COM_ImageOperation.h
index e75e7daa18..9a7d2d4d79 100644
--- a/source/blender/compositor/operations/COM_ImageOperation.h
+++ b/source/blender/compositor/operations/COM_ImageOperation.h
@@ -40,6 +40,7 @@ extern "C" {
 class BaseImageOperation : public NodeOperation {
 protected:
 	ImBuf *m_buffer;
+	ImBuf *m_secondaryBuffer;
 	Image *m_image;
 	ImageUser *m_imageUser;
 	float *m_imageBuffer;
@@ -65,14 +66,17 @@ public:
 	void setImageUser(ImageUser *imageuser) { this->m_imageUser = imageuser; }
 
 	void setFramenumber(int framenumber) { this->m_framenumber = framenumber; }
+	
+	void initSecondaryBuffer(int buffer_type);
 };
 class ImageOperation : public BaseImageOperation {
+protected:
 public:
 	/**
 	 * Constructor
 	 */
 	ImageOperation();
-	void executePixel(float output[4], float x, float y, PixelSampler sampler);
+	void executePixel(float output[4], float x, float y, PixelSampler sampler); 
 };
 class ImageAlphaOperation : public BaseImageOperation {
 public:
diff --git a/source/blender/compositor/operations/COM_MultilayerImageOperation.cpp b/source/blender/compositor/operations/COM_MultilayerImageOperation.cpp
index af0d516183..f7450bd560 100644
--- a/source/blender/compositor/operations/COM_MultilayerImageOperation.cpp
+++ b/source/blender/compositor/operations/COM_MultilayerImageOperation.cpp
@@ -62,6 +62,13 @@ void MultilayerColorOperation::executePixel(float output[4], float x, float y, P
 				case COM_PS_BICUBIC:
 					bicubic_interpolation_color(this->m_buffer, NULL, output, x, y);
 					break;
+    			case COM_PS_CUBICBSPLINEPREFILTER:
+			        lockMutex();
+			        if (this->m_secondaryBuffer == NULL) {
+			            BaseImageOperation::initSecondaryBuffer(BT_CUBICBSPLINEPREFILTER);
+			        }
+			        unlockMutex();
+			        bicubic_interpolation_color(this->m_secondaryBuffer, NULL, output, x, y);
 			}
 		}
 		else {
diff --git a/source/blender/imbuf/IMB_imbuf.h b/source/blender/imbuf/IMB_imbuf.h
index 28dbe11052..1049477ac1 100644
--- a/source/blender/imbuf/IMB_imbuf.h
+++ b/source/blender/imbuf/IMB_imbuf.h
@@ -416,6 +416,20 @@ void bilinear_interpolation_color(struct ImBuf *in, unsigned char col[4], float
 void bilinear_interpolation_color_wrap(struct ImBuf *in, unsigned char col[4], float col_float[4], float u, float v);
 
 /**
+ * Establish the prefilter algorithm at lowest level to be adopted
+ * by other areas of Blender such as MIPmaps.
+ */
+
+/* Buffer Types */
+#define BT_DUPLICATE                    0
+#define BT_CUBICBSPLINEPREFILTER        1
+
+void prefilter_initInitialCausal(float *coeffIn, float *sum, unsigned int length, unsigned int stride);
+void prefilter_initInitialAntiCausal(float *coeffIn);
+void prefilter_doRecursion(float *coeffIn, unsigned int length, unsigned int stride);
+void create_prefilter(struct ImBuf *in, struct ImBuf *out);
+
+/**
  *
  * \attention defined in readimage.c
  */  
diff --git a/source/blender/imbuf/intern/imageprocess.c b/source/blender/imbuf/intern/imageprocess.c
index 863b8424cc..f5662e4fa6 100644
--- a/source/blender/imbuf/intern/imageprocess.c
+++ b/source/blender/imbuf/intern/imageprocess.c
@@ -47,6 +47,7 @@
 #include "IMB_imbuf_types.h"
 #include "IMB_imbuf.h"
 #include <math.h>
+#include <string.h>
 
 /* Only this one is used liberally here, and in imbuf */
 void IMB_convert_rgba_to_abgr(struct ImBuf *ibuf)
@@ -461,6 +462,117 @@ void neareast_interpolation(ImBuf *in, ImBuf *out, float x, float y, int xout, i
 	neareast_interpolation_color(in, outI, outF, x, y);
 }
 
+/*********************** CubicBSpline Prefilter ****************************/
+/* This function creates a prefilter in the frequency domain. It can be
+   viewed as a compliment to a traditional bicubic filter. */
+
+void create_prefilter(ImBuf *in, ImBuf *out)
+{
+    int x, y;
+    
+    // A row of float coefficients.
+    float *coeff = out->rect_float;
+    
+    if (in == NULL || in->rect_float == NULL || out == NULL ||
+        out->rect_float == NULL || in->x <= 2 || in->y <=2)
+        return;
+	
+	// Initialize
+	memcpy(coeff, in->rect_float, in->x * in->y * 4 * sizeof(float));
+
+    // X Recursion
+    for(y = 0; y < in->y; y++)
+        prefilter_doRecursion(&coeff[y * in->x * 4], in->x, 4);
+    // Y Recursion
+    for(x = 0; x < in->x; x++)
+        prefilter_doRecursion(&coeff[x * 4], in->y, in->x * 4);
+        
+    // Copy to the out ImBuf.
+    memcpy(out->rect_float, coeff, (in->x * in->y * 4 * sizeof(float)));
+}
+
+// Get the initial causual coefficient for a given run of floats at stride count
+// of floats.
+void prefilter_initInitialCausal(float *coeffIn, float *sum, unsigned int length, unsigned int stride)
+{
+    const float Zp = sqrt(3.0f)-2.0f;
+    const float lambda = (1.0f - Zp) * (1.0f - 1.0f / Zp);
+    unsigned int count = 0, horizon = MIN2(12, length) * 4;
+    float Zn = Zp;
+    
+    sum[0] = coeffIn[0]; // R
+    sum[1] = coeffIn[1]; // G
+    sum[2] = coeffIn[2]; // B
+    sum[3] = coeffIn[3]; // A
+    
+    for (count = 0; count < horizon; count += stride) {
+	    sum[0] += Zn * coeffIn[count];    // R
+	    sum[1] += Zn * coeffIn[count+1];  // G
+	    sum[2] += Zn * coeffIn[count+2];  // B
+	    sum[3] += Zn * coeffIn[count+3];  // A
+	    
+        Zn *= Zp;
+    }
+    
+    coeffIn[0] = (lambda * sum[0]); // R
+    coeffIn[1] = (lambda * sum[1]); // G
+    coeffIn[2] = (lambda * sum[2]); // B
+    coeffIn[3] = (lambda * sum[3]); // A
+}
+
+// Set the initial anti-causual coefficient at the end of the given run of
+// floats at stride count of floats.
+void prefilter_initInitialAntiCausal(float *coeffIn)
+{
+    const float Zp  = sqrt(3.0f)-2.0f;
+    const float iZp = (Zp / (Zp - 1.0f));
+    
+    coeffIn[0] = iZp * coeffIn[0]; //R
+    coeffIn[1] = iZp * coeffIn[1]; //G
+    coeffIn[2] = iZp * coeffIn[2]; //B
+    coeffIn[3] = iZp * coeffIn[3]; //A
+}
+
+
+void prefilter_doRecursion(float *coeffIn, unsigned int length, unsigned int stride)
+{
+    const float Zp  = sqrt(3.0f)-2.0f;
+    const float lambda = (1.0f - Zp) * (1.0f - 1.0f / Zp);
+    float prevcoeff[4] = { 0, 0, 0, 0 };
+    float sum[4] = { 0, 0, 0, 0 };
+    int count = 0;
+    unsigned int total_floats = length * 4;
+    
+    prefilter_initInitialCausal(coeffIn, sum, length, 4);
+    
+    prevcoeff[0] = coeffIn[0]; // R
+    prevcoeff[1] = coeffIn[1]; // G
+    prevcoeff[2] = coeffIn[2]; // B
+    prevcoeff[3] = coeffIn[3]; // A
+    
+    for (count = (1 * stride); count < total_floats; count += stride) {
+        coeffIn[count]     = prevcoeff[0] = (lambda * coeffIn[count])     + (Zp * prevcoeff[0]); // R
+        coeffIn[count + 1] = prevcoeff[1] = (lambda * coeffIn[count + 1]) + (Zp * prevcoeff[1]); // G
+        coeffIn[count + 2] = prevcoeff[2] = (lambda * coeffIn[count + 2]) + (Zp * prevcoeff[2]); // B
+        coeffIn[count + 3] = prevcoeff[3] = (lambda * coeffIn[count + 3]) + (Zp * prevcoeff[3]); // A
+    }
+    
+    count -= stride;
+    prefilter_initInitialAntiCausal(&coeffIn[count]);
+   
+    prevcoeff[0] = coeffIn[count];     // R
+    prevcoeff[1] = coeffIn[count + 1]; // G
+    prevcoeff[2] = coeffIn[count + 2]; // B
+    prevcoeff[3] = coeffIn[count + 3]; // A
+
+    for (count -= stride; count >= 0; count -= stride) {
+        coeffIn[count]     = prevcoeff[0] = Zp * (prevcoeff[0] - coeffIn[count]);     // R
+        coeffIn[count + 1] = prevcoeff[1] = Zp * (prevcoeff[1] - coeffIn[count + 1]); // G
+        coeffIn[count + 2] = prevcoeff[2] = Zp * (prevcoeff[2] - coeffIn[count + 2]); // B
+        coeffIn[count + 3] = prevcoeff[3] = Zp * (prevcoeff[3] - coeffIn[count + 3]); // A
+    }
+}
+
 /*********************** Threaded image processing *************************/
 
 void IMB_processor_apply_threaded(int buffer_lines, int handle_size, void *init_customdata,
diff --git a/source/blender/makesrna/intern/rna_nodetree.c b/source/blender/makesrna/intern/rna_nodetree.c
index 0d7d20d04a..613526734a 100644
--- a/source/blender/makesrna/intern/rna_nodetree.c
+++ b/source/blender/makesrna/intern/rna_nodetree.c
@@ -137,6 +137,7 @@ EnumPropertyItem node_sampler_type_items[] = {
 	{0, "NEAREST",   0, "Nearest",   ""},
 	{1, "BILINEAR",   0, "Bilinear",   ""},
 	{2, "BICUBIC", 0, "Bicubic", ""},
+	{3, "CUBICBSPLINEPREFILTER", 0, "Cubic B Spline with Prefilter", ""},
 	{0, NULL, 0, NULL, NULL}
 };