D627: Memory usage optimization for the compositor.

The compostor used a fixed size of 4 floats to hold pixel data. this
patch will select size of a pixel based on its type.
It uses 1 float for Value, 3 float for vector and 4 floats for color
data types.

When benchmarking on shots (opening shot of caminandes) we get a
reduction of memory of 30% and a tiny speedup as less data
transformations needs to take place (but these are negligable.

More information of the patch can be found on
https://developer.blender.org/D627 and
http://wiki.blender.org/index.php/Dev:Ref/Proposals/Compositor2014_p1.1_TD

Developers: jbakker & mdewanchand
Thanks for Sergey for his indept review.

11 files changed, 195 insertions, 269 deletions

diff --git a/source/blender/compositor/intern/COM_ChannelInfo.cpp b/source/blender/compositor/intern/COM_ChannelInfo.cpp
deleted file mode 100644
index 557075cdc80..00000000000
--- a/source/blender/compositor/intern/COM_ChannelInfo.cpp
+++ /dev/null
@@ -1,35 +0,0 @@
-/*
- * Copyright 2011, Blender Foundation.
- *
- * 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 2
- * 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, write to the Free Software Foundation,
- * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
- *
- * Contributor: 
- *		Jeroen Bakker 
- *		Monique Dewanchand
- */
-
-#include "COM_ChannelInfo.h"
-#include "COM_defines.h"
-#include <stdio.h>
-
-/**
- * @brief create new ChannelInfo instance and sets the defaults.
- */
-ChannelInfo::ChannelInfo()
-{
-	this->m_number = 0;
-	this->m_premultiplied = true;
-	this->m_type = COM_CT_UNUSED;
-}
diff --git a/source/blender/compositor/intern/COM_ChannelInfo.h b/source/blender/compositor/intern/COM_ChannelInfo.h
deleted file mode 100644
index ec78e7e1cb1..00000000000
--- a/source/blender/compositor/intern/COM_ChannelInfo.h
+++ /dev/null
@@ -1,121 +0,0 @@
-/*
- * Copyright 2011, Blender Foundation.
- *
- * 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 2
- * 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, write to the Free Software Foundation,
- * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
- *
- * Contributor: 
- *		Jeroen Bakker 
- *		Monique Dewanchand
- */
-
-#ifndef _COM_ChannelInfo_h
-#define _COM_ChannelInfo_h
-
-#include <vector>
-#include "BKE_text.h"
-#include <string>
-#include "DNA_node_types.h"
-#include "BLI_rect.h"
-
-using namespace std;
-
-/**
- * @brief List of possible channel types
- * @ingroup Model
- */
-typedef enum ChannelType {
-	COM_CT_ColorComponent /** @brief this channel is contains color information. Specific used is determined by channelnumber, and in the future color space */,
-	COM_CT_Alpha /** @brief this channel is contains transparency value */,
-	COM_CT_Value /** @brief this channel is contains a value */,
-	COM_CT_X /** @brief this channel is contains a X value */,
-	COM_CT_Y /** @brief this channel is contains a Y value */,
-	COM_CT_Z /** @brief this channel is contains a Z value */,
-	COM_CT_W /** @brief this channel is contains a W value */,
-	COM_CT_UNUSED /** @brief this channel is unused */
-} ChannelType;
-
-/**
- * @brief ChannelInfo holds information about a channel.
- *
- * Channels are transported from node to node via a NodeLink.
- * ChannelInfo holds specific setting of these channels in order that the to-node of the link
- * Can handle specific logic per channel setting.
- *
- * @note currently this is not used, but a future place to implement color spacing and other things.
- * @ingroup Model
- */
-class ChannelInfo {
-private:
-	/**
-	 * @brief the channel number, in the link. [0-3]
-	 */
-	int m_number;
-
-	/**
-	 * @brief type of channel
-	 */
-	ChannelType m_type;
-
-	/**
-	 * @brieg Is this value in this channel premultiplied with its alpha
-	 * @note only valid if type = ColorComponent;
-	 */
-	bool m_premultiplied;
-
-//	/**
-//	 * Color space of this value.
-//	 * only valid when type = ColorComponent;
-//	 */
-//	string colorspacename;
-
-public:
-	/**
-	 * @brief creates a new ChannelInfo and set default values
-	 */
-	ChannelInfo();
-
-	/**
-	 * @brief set the index of this channel in the NodeLink
-	 */
-	void setNumber(const int number) { this->m_number = number; }
-
-	/**
-	 * @brief get the index of this channel in the NodeLink
-	 */
-	const int getNumber() const { return this->m_number; }
-
-	/**
-	 * @brief set the type of channel
-	 */
-	void setType(const ChannelType type) { this->m_type = type; }
-
-	/**
-	 * @brief get the type of channel
-	 */
-	const ChannelType getType() const { return this->m_type; }
-
-	/**
-	 * @brief set the premultiplicatioin of this channel
-	 */
-	void setPremultiplied(const bool premultiplied) { this->m_premultiplied = premultiplied; }
-
-	/**
-	 * @brief is this channel premultiplied
-	 */
-	const bool isPremultiplied() const { return this->m_premultiplied; }
-};
-
-
-#endif
diff --git a/source/blender/compositor/intern/COM_ExecutionSystem.cpp b/source/blender/compositor/intern/COM_ExecutionSystem.cpp
index 7c08188db90..0667271f4b1 100644
--- a/source/blender/compositor/intern/COM_ExecutionSystem.cpp
+++ b/source/blender/compositor/intern/COM_ExecutionSystem.cpp
@@ -137,11 +137,15 @@ void ExecutionSystem::execute()
 	}
 	unsigned int index;
 
+	// First allocale all write buffer
 	for (index = 0; index < this->m_operations.size(); index++) {
 		NodeOperation *operation = this->m_operations[index];
-		operation->setbNodeTree(this->m_context.getbNodeTree());
-		operation->initExecution();
+		if (operation->isWriteBufferOperation()) {
+			operation->setbNodeTree(this->m_context.getbNodeTree());
+			operation->initExecution();
+		}
 	}
+	// Connect read buffers to their write buffers
 	for (index = 0; index < this->m_operations.size(); index++) {
 		NodeOperation *operation = this->m_operations[index];
 		if (operation->isReadBufferOperation()) {
@@ -149,6 +153,14 @@ void ExecutionSystem::execute()
 			readOperation->updateMemoryBuffer();
 		}
 	}
+	// initialize other operations
+	for (index = 0; index < this->m_operations.size(); index++) {
+		NodeOperation *operation = this->m_operations[index];
+		if (!operation->isWriteBufferOperation()) {
+			operation->setbNodeTree(this->m_context.getbNodeTree());
+			operation->initExecution();
+		}
+	}
 	for (index = 0; index < this->m_groups.size(); index++) {
 		ExecutionGroup *executionGroup = this->m_groups[index];
 		executionGroup->setChunksize(this->m_context.getChunksize());
diff --git a/source/blender/compositor/intern/COM_MemoryBuffer.cpp b/source/blender/compositor/intern/COM_MemoryBuffer.cpp
index c59ecced93c..58767960cc8 100644
--- a/source/blender/compositor/intern/COM_MemoryBuffer.cpp
+++ b/source/blender/compositor/intern/COM_MemoryBuffer.cpp
@@ -27,6 +27,18 @@
 using std::min;
 using std::max;
 
+static unsigned int determine_num_channels(DataType datatype) {
+	switch (datatype) {
+	case COM_DT_VALUE:
+		return COM_NUM_CHANNELS_VALUE;
+	case COM_DT_VECTOR:
+		return COM_NUM_CHANNELS_VECTOR;
+	case COM_DT_COLOR:
+	default:
+		return COM_NUM_CHANNELS_COLOR;
+	}
+}
+
 unsigned int MemoryBuffer::determineBufferSize()
 {
 	return getWidth() * getHeight();
@@ -34,61 +46,62 @@ unsigned int MemoryBuffer::determineBufferSize()
 
 int MemoryBuffer::getWidth() const
 {
-	return this->m_rect.xmax - this->m_rect.xmin;
+	return this->m_width;
 }
 int MemoryBuffer::getHeight() const
 {
-	return this->m_rect.ymax - this->m_rect.ymin;
+	return this->m_height;
 }
 
 MemoryBuffer::MemoryBuffer(MemoryProxy *memoryProxy, unsigned int chunkNumber, rcti *rect)
 {
 	BLI_rcti_init(&this->m_rect, rect->xmin, rect->xmax, rect->ymin, rect->ymax);
+	this->m_width = BLI_rcti_size_x(&this->m_rect);
+	this->m_height = BLI_rcti_size_y(&this->m_rect);
 	this->m_memoryProxy = memoryProxy;
 	this->m_chunkNumber = chunkNumber;
-	this->m_buffer = (float *)MEM_mallocN_aligned(sizeof(float) * determineBufferSize() * COM_NUMBER_OF_CHANNELS, 16, "COM_MemoryBuffer");
+	this->m_num_channels = determine_num_channels(memoryProxy->getDataType());
+	this->m_buffer = (float *)MEM_mallocN_aligned(sizeof(float) * determineBufferSize() * this->m_num_channels, 16, "COM_MemoryBuffer");
 	this->m_state = COM_MB_ALLOCATED;
-	this->m_datatype = COM_DT_COLOR;
-	this->m_chunkWidth = this->m_rect.xmax - this->m_rect.xmin;
+	this->m_datatype = memoryProxy->getDataType();;
 }
 
 MemoryBuffer::MemoryBuffer(MemoryProxy *memoryProxy, rcti *rect)
 {
 	BLI_rcti_init(&this->m_rect, rect->xmin, rect->xmax, rect->ymin, rect->ymax);
+	this->m_width = BLI_rcti_size_x(&this->m_rect);
+	this->m_height = BLI_rcti_size_y(&this->m_rect);
 	this->m_memoryProxy = memoryProxy;
 	this->m_chunkNumber = -1;
-	this->m_buffer = (float *)MEM_mallocN_aligned(sizeof(float) * determineBufferSize() * COM_NUMBER_OF_CHANNELS, 16, "COM_MemoryBuffer");
+	this->m_num_channels = determine_num_channels(memoryProxy->getDataType());
+	this->m_buffer = (float *)MEM_mallocN_aligned(sizeof(float) * determineBufferSize() * this->m_num_channels, 16, "COM_MemoryBuffer");
+	this->m_state = COM_MB_TEMPORARILY;
+	this->m_datatype = memoryProxy->getDataType();
+}
+MemoryBuffer::MemoryBuffer(DataType dataType, rcti *rect)
+{
+	BLI_rcti_init(&this->m_rect, rect->xmin, rect->xmax, rect->ymin, rect->ymax);
+	this->m_width = BLI_rcti_size_x(&this->m_rect);
+	this->m_height = BLI_rcti_size_y(&this->m_rect);
+	this->m_height = this->m_rect.ymax - this->m_rect.ymin;
+	this->m_memoryProxy = NULL;
+	this->m_chunkNumber = -1;
+	this->m_num_channels = determine_num_channels(dataType);
+	this->m_buffer = (float *)MEM_mallocN_aligned(sizeof(float) * determineBufferSize() * this->m_num_channels, 16, "COM_MemoryBuffer");
 	this->m_state = COM_MB_TEMPORARILY;
-	this->m_datatype = COM_DT_COLOR;
-	this->m_chunkWidth = this->m_rect.xmax - this->m_rect.xmin;
+	this->m_datatype = dataType;
 }
 MemoryBuffer *MemoryBuffer::duplicate()
 {
 	MemoryBuffer *result = new MemoryBuffer(this->m_memoryProxy, &this->m_rect);
-	memcpy(result->m_buffer, this->m_buffer, this->determineBufferSize() * COM_NUMBER_OF_CHANNELS * sizeof(float));
+	memcpy(result->m_buffer, this->m_buffer, this->determineBufferSize() * this->m_num_channels * sizeof(float));
 	return result;
 }
 void MemoryBuffer::clear()
 {
-	memset(this->m_buffer, 0, this->determineBufferSize() * COM_NUMBER_OF_CHANNELS * sizeof(float));
+	memset(this->m_buffer, 0, this->determineBufferSize() * this->m_num_channels * sizeof(float));
 }
 
-float *MemoryBuffer::convertToValueBuffer()
-{
-	const unsigned int size = this->determineBufferSize();
-	unsigned int i;
-
-	float *result = (float *)MEM_mallocN(sizeof(float) * size, __func__);
-
-	const float *fp_src = this->m_buffer;
-	float       *fp_dst = result;
-
-	for (i = 0; i < size; i++, fp_dst++, fp_src += COM_NUMBER_OF_CHANNELS) {
-		*fp_dst = *fp_src;
-	}
-
-	return result;
-}
 
 float MemoryBuffer::getMaximumValue()
 {
@@ -98,7 +111,7 @@ float MemoryBuffer::getMaximumValue()
 
 	const float *fp_src = this->m_buffer;
 
-	for (i = 0; i < size; i++, fp_src += COM_NUMBER_OF_CHANNELS) {
+	for (i = 0; i < size; i++, fp_src += this->m_num_channels) {
 		float value = *fp_src;
 		if (value > result) {
 			result = value;
@@ -116,7 +129,7 @@ float MemoryBuffer::getMaximumValue(rcti *rect)
 	BLI_rcti_isect(rect, &this->m_rect, &rect_clamp);
 
 	if (!BLI_rcti_is_empty(&rect_clamp)) {
-		MemoryBuffer *temp = new MemoryBuffer(NULL, &rect_clamp);
+		MemoryBuffer *temp = new MemoryBuffer(this->m_datatype, &rect_clamp);
 		temp->copyContentFrom(this);
 		float result = temp->getMaximumValue();
 		delete temp;
@@ -152,9 +165,9 @@ void MemoryBuffer::copyContentFrom(MemoryBuffer *otherBuffer)
 
 
 	for (otherY = minY; otherY < maxY; otherY++) {
-		otherOffset = ((otherY - otherBuffer->m_rect.ymin) * otherBuffer->m_chunkWidth + minX - otherBuffer->m_rect.xmin) * COM_NUMBER_OF_CHANNELS;
-		offset = ((otherY - this->m_rect.ymin) * this->m_chunkWidth + minX - this->m_rect.xmin) * COM_NUMBER_OF_CHANNELS;
-		memcpy(&this->m_buffer[offset], &otherBuffer->m_buffer[otherOffset], (maxX - minX) * COM_NUMBER_OF_CHANNELS * sizeof(float));
+		otherOffset = ((otherY - otherBuffer->m_rect.ymin) * otherBuffer->m_width + minX - otherBuffer->m_rect.xmin) * this->m_num_channels;
+		offset = ((otherY - this->m_rect.ymin) * this->m_width + minX - this->m_rect.xmin) * this->m_num_channels;
+		memcpy(&this->m_buffer[offset], &otherBuffer->m_buffer[otherOffset], (maxX - minX) * this->m_num_channels * sizeof(float));
 	}
 }
 
@@ -163,9 +176,8 @@ void MemoryBuffer::writePixel(int x, int y, const float color[4])
 	if (x >= this->m_rect.xmin && x < this->m_rect.xmax &&
 	    y >= this->m_rect.ymin && y < this->m_rect.ymax)
 	{
-		const int offset = (this->m_chunkWidth * (y - this->m_rect.ymin) + x - this->m_rect.xmin) * COM_NUMBER_OF_CHANNELS;
-		copy_v4_v4(&this->m_buffer[offset], color);
-	}
+		const int offset = (this->m_width * (y - this->m_rect.ymin) + x - this->m_rect.xmin) * this->m_num_channels;
+		memcpy(&this->m_buffer[offset], color, sizeof(float)*this->m_num_channels);	}
 }
 
 void MemoryBuffer::addPixel(int x, int y, const float color[4])
@@ -173,8 +185,12 @@ void MemoryBuffer::addPixel(int x, int y, const float color[4])
 	if (x >= this->m_rect.xmin && x < this->m_rect.xmax &&
 	    y >= this->m_rect.ymin && y < this->m_rect.ymax)
 	{
-		const int offset = (this->m_chunkWidth * (y - this->m_rect.ymin) + x - this->m_rect.xmin) * COM_NUMBER_OF_CHANNELS;
-		add_v4_v4(&this->m_buffer[offset], color);
+		const int offset = (this->m_width * (y - this->m_rect.ymin) + x - this->m_rect.xmin) * this->m_num_channels;
+		 float *dst = &this->m_buffer[offset];
+		 const float *src = color;
+		 for (int i = 0; i < this->m_num_channels ; i++, dst++, src++) {
+			 *dst += *src;
+		 }
 	}
 }
 
@@ -208,8 +224,9 @@ static void read_ewa_pixel_sampled(void *userdata, int x, int y, float result[4]
 	}
 }
 
-void MemoryBuffer::readEWA(float result[4], const float uv[2], const float derivatives[2][2], PixelSampler sampler)
+void MemoryBuffer::readEWA(float *result, const float uv[2], const float derivatives[2][2], PixelSampler sampler)
 {
+	BLI_assert(this->m_datatype==COM_DT_COLOR);
 	ReadEWAData data;
 	data.buffer = this;
 	data.sampler = sampler;
diff --git a/source/blender/compositor/intern/COM_MemoryBuffer.h b/source/blender/compositor/intern/COM_MemoryBuffer.h
index d6ef9cd673e..70b4dec2bed 100644
--- a/source/blender/compositor/intern/COM_MemoryBuffer.h
+++ b/source/blender/compositor/intern/COM_MemoryBuffer.h
@@ -83,11 +83,6 @@ private:
 	unsigned int m_chunkNumber;
 	
 	/**
-	 * @brief width of the chunk
-	 */
-	unsigned int m_chunkWidth;
-	
-	/**
 	 * @brief state of the buffer
 	 */
 	MemoryBufferState m_state;
@@ -97,6 +92,15 @@ private:
 	 */
 	float *m_buffer;
 
+	/**
+	 * @brief the number of channels of a single value in the buffer.
+	 * For value buffers this is 1, vector 3 and color 4
+	 */
+	unsigned int m_num_channels;
+
+	int m_width;
+	int m_height;
+
 public:
 	/**
 	 * @brief construct new MemoryBuffer for a chunk
@@ -107,7 +111,12 @@ public:
 	 * @brief construct new temporarily MemoryBuffer for an area
 	 */
 	MemoryBuffer(MemoryProxy *memoryProxy, rcti *rect);
-	
+
+	/**
+	 * @brief construct new temporarily MemoryBuffer for an area
+	 */
+	MemoryBuffer(DataType datatype, rcti *rect);
+
 	/**
 	 * @brief destructor
 	 */
@@ -117,7 +126,9 @@ public:
 	 * @brief read the ChunkNumber of this MemoryBuffer
 	 */
 	unsigned int getChunkNumber() { return this->m_chunkNumber; }
-	
+
+	unsigned int get_num_channels() { return this->m_num_channels; }
+
 	/**
 	 * @brief get the data of this MemoryBuffer
 	 * @note buffer should already be available in memory
@@ -134,8 +145,8 @@ public:
 	
 	inline void wrap_pixel(int &x, int &y, MemoryBufferExtend extend_x, MemoryBufferExtend extend_y)
 	{
-		int w = m_rect.xmax - m_rect.xmin;
-		int h = m_rect.ymax - m_rect.ymin;
+		int w = this->m_width;
+		int h = this->m_height;
 		x = x - m_rect.xmin;
 		y = y - m_rect.ymin;
 		
@@ -164,7 +175,39 @@ public:
 		}
 	}
 	
-	inline void read(float result[4], int x, int y,
+	inline void wrap_pixel(float &x, float &y, MemoryBufferExtend extend_x, MemoryBufferExtend extend_y)
+	{
+		float w = (float)this->m_width;
+		float h = (float)this->m_height;
+		x = x - m_rect.xmin;
+		y = y - m_rect.ymin;
+
+		switch (extend_x) {
+			case COM_MB_CLIP:
+				break;
+			case COM_MB_EXTEND:
+				if (x < 0) x = 0.0f;
+				if (x >= w) x = w;
+				break;
+			case COM_MB_REPEAT:
+				x = fmodf(x, w);
+				break;
+		}
+
+		switch (extend_y) {
+			case COM_MB_CLIP:
+				break;
+			case COM_MB_EXTEND:
+				if (y < 0) y = 0.0f;
+				if (y >= h) y = h;
+				break;
+			case COM_MB_REPEAT:
+				y = fmodf(y, h);
+				break;
+		}
+	}
+
+	inline void read(float *result, int x, int y,
 	                 MemoryBufferExtend extend_x = COM_MB_CLIP,
 	                 MemoryBufferExtend extend_y = COM_MB_CLIP)
 	{
@@ -172,81 +215,54 @@ public:
 		bool clip_y = (extend_y == COM_MB_CLIP && (y < m_rect.ymin || y >= m_rect.ymax));
 		if (clip_x || clip_y) {
 			/* clip result outside rect is zero */
-			zero_v4(result);
+			memset(result, 0, this->m_num_channels*sizeof(float));
 		}
 		else {
-			wrap_pixel(x, y, extend_x, extend_y);
-			const int offset = (this->m_chunkWidth * y + x) * COM_NUMBER_OF_CHANNELS;
-			copy_v4_v4(result, &this->m_buffer[offset]);
+			int u = x;
+			int v = y;
+			this->wrap_pixel(u, v, extend_x, extend_y);
+			const int offset = (this->m_width * y + x) * this->m_num_channels;
+			float* buffer = &this->m_buffer[offset];
+			memcpy(result, buffer, sizeof(float)*this->m_num_channels);
 		}
 	}
 
-	inline void readNoCheck(float result[4], int x, int y,
+	inline void readNoCheck(float *result, int x, int y,
 	                        MemoryBufferExtend extend_x = COM_MB_CLIP,
 	                        MemoryBufferExtend extend_y = COM_MB_CLIP)
 	{
-		wrap_pixel(x, y, extend_x, extend_y);
-		const int offset = (this->m_chunkWidth * y + x) * COM_NUMBER_OF_CHANNELS;
+		int u = x;
+		int v = y;
 
-		BLI_assert(offset >= 0);
-		BLI_assert(offset < this->determineBufferSize() * COM_NUMBER_OF_CHANNELS);
-		BLI_assert(!(extend_x == COM_MB_CLIP && (x < m_rect.xmin || x >= m_rect.xmax)) &&
-		           !(extend_y == COM_MB_CLIP && (y < m_rect.ymin || y >= m_rect.ymax)));
+		this->wrap_pixel(u, v, extend_x, extend_y);
+		const int offset = (this->m_width * v + u) * this->m_num_channels;
 
+		BLI_assert(offset >= 0);
+		BLI_assert(offset < this->determineBufferSize() * this->m_num_channels);
+		BLI_assert(!(extend_x == COM_MB_CLIP && (u < m_rect.xmin || u >= m_rect.xmax)) &&
+				   !(extend_y == COM_MB_CLIP && (v < m_rect.ymin || v >= m_rect.ymax)));
 #if 0
 		/* always true */
 		BLI_assert((int)(MEM_allocN_len(this->m_buffer) / sizeof(*this->m_buffer)) ==
 		           (int)(this->determineBufferSize() * COM_NUMBER_OF_CHANNELS));
 #endif
-
-		copy_v4_v4(result, &this->m_buffer[offset]);
+		float* buffer = &this->m_buffer[offset];
+		memcpy(result, buffer, sizeof(float)*this->m_num_channels);
 	}
 	
 	void writePixel(int x, int y, const float color[4]);
 	void addPixel(int x, int y, const float color[4]);
-	inline void readBilinear(float result[4], float x, float y,
+	inline void readBilinear(float *result, float x, float y,
 	                         MemoryBufferExtend extend_x = COM_MB_CLIP,
 	                         MemoryBufferExtend extend_y = COM_MB_CLIP)
 	{
-		int x1 = floor(x);
-		int y1 = floor(y);
-		int x2 = x1 + 1;
-		int y2 = y1 + 1;
-		wrap_pixel(x1, y1, extend_x, extend_y);
-		wrap_pixel(x2, y2, extend_x, extend_y);
-
-		float valuex = x - x1;
-		float valuey = y - y1;
-		float mvaluex = 1.0f - valuex;
-		float mvaluey = 1.0f - valuey;
-
-		float color1[4];
-		float color2[4];
-		float color3[4];
-		float color4[4];
-
-		read(color1, x1, y1);
-		read(color2, x1, y2);
-		read(color3, x2, y1);
-		read(color4, x2, y2);
-
-		color1[0] = color1[0] * mvaluey + color2[0] * valuey;
-		color1[1] = color1[1] * mvaluey + color2[1] * valuey;
-		color1[2] = color1[2] * mvaluey + color2[2] * valuey;
-		color1[3] = color1[3] * mvaluey + color2[3] * valuey;
-
-		color3[0] = color3[0] * mvaluey + color4[0] * valuey;
-		color3[1] = color3[1] * mvaluey + color4[1] * valuey;
-		color3[2] = color3[2] * mvaluey + color4[2] * valuey;
-		color3[3] = color3[3] * mvaluey + color4[3] * valuey;
-
-		result[0] = color1[0] * mvaluex + color3[0] * valuex;
-		result[1] = color1[1] * mvaluex + color3[1] * valuex;
-		result[2] = color1[2] * mvaluex + color3[2] * valuex;
-		result[3] = color1[3] * mvaluex + color3[3] * valuex;
+		float u = x;
+		float v = y;
+		this->wrap_pixel(u, v, extend_x, extend_y);
+		BLI_bilinear_interpolation_fl(this->m_buffer, result, this->m_width, this->m_height, this->m_num_channels, u, v);
 	}
 
-	void readEWA(float result[4], const float uv[2], const float derivatives[2][2], PixelSampler sampler);
+	void readEWA(float *result, const float uv[2], const float derivatives[2][2], PixelSampler sampler);
 	
 	/**
 	 * @brief is this MemoryBuffer a temporarily buffer (based on an area, not on a chunk)
@@ -284,7 +300,6 @@ public:
 	
 	MemoryBuffer *duplicate();
 	
-	float *convertToValueBuffer();
 	float getMaximumValue();
 	float getMaximumValue(rcti *rect);
 private:
diff --git a/source/blender/compositor/intern/COM_MemoryProxy.cpp b/source/blender/compositor/intern/COM_MemoryProxy.cpp
index 90ca0baea06..1df3e59db62 100644
--- a/source/blender/compositor/intern/COM_MemoryProxy.cpp
+++ b/source/blender/compositor/intern/COM_MemoryProxy.cpp
@@ -23,10 +23,11 @@
 #include "COM_MemoryProxy.h"
 
 
-MemoryProxy::MemoryProxy()
+MemoryProxy::MemoryProxy(DataType datatype)
 {
 	this->m_writeBufferOperation = NULL;
 	this->m_executor = NULL;
+	this->m_datatype = datatype;
 }
 
 void MemoryProxy::allocate(unsigned int width, unsigned int height)
diff --git a/source/blender/compositor/intern/COM_MemoryProxy.h b/source/blender/compositor/intern/COM_MemoryProxy.h
index 233b035a2d7..b332852088b 100644
--- a/source/blender/compositor/intern/COM_MemoryProxy.h
+++ b/source/blender/compositor/intern/COM_MemoryProxy.h
@@ -63,8 +63,13 @@ private:
 	 */
 	MemoryBuffer *m_buffer;
 
+	/**
+	 * @brief datatype of this MemoryProxy
+	 */
+	DataType m_datatype;
+
 public:
-	MemoryProxy();
+	MemoryProxy(DataType type);
 	
 	/**
 	 * @brief set the ExecutionGroup that can be scheduled to calculate a certain chunk.
@@ -104,6 +109,8 @@ public:
 	 */
 	inline MemoryBuffer *getBuffer() { return this->m_buffer; }
 
+	inline DataType getDataType() { return this->m_datatype; }
+
 #ifdef WITH_CXX_GUARDEDALLOC
 	MEM_CXX_CLASS_ALLOC_FUNCS("COM:MemoryProxy")
 #endif
diff --git a/source/blender/compositor/intern/COM_NodeOperationBuilder.cpp b/source/blender/compositor/intern/COM_NodeOperationBuilder.cpp
index fb5bc8fcd9b..74c05c3e62e 100644
--- a/source/blender/compositor/intern/COM_NodeOperationBuilder.cpp
+++ b/source/blender/compositor/intern/COM_NodeOperationBuilder.cpp
@@ -476,7 +476,7 @@ void NodeOperationBuilder::add_input_buffers(NodeOperation *operation, NodeOpera
 	/* check of other end already has write operation, otherwise add a new one */
 	WriteBufferOperation *writeoperation = find_attached_write_buffer_operation(output);
 	if (!writeoperation) {
-		writeoperation = new WriteBufferOperation();
+		writeoperation = new WriteBufferOperation(output->getDataType());
 		writeoperation->setbNodeTree(m_context->getbNodeTree());
 		addOperation(writeoperation);
 		
@@ -486,7 +486,7 @@ void NodeOperationBuilder::add_input_buffers(NodeOperation *operation, NodeOpera
 	}
 	
 	/* add readbuffer op for the input */
-	ReadBufferOperation *readoperation = new ReadBufferOperation();
+	ReadBufferOperation *readoperation = new ReadBufferOperation(output->getDataType());
 	readoperation->setMemoryProxy(writeoperation->getMemoryProxy());
 	this->addOperation(readoperation);
 	
@@ -519,7 +519,7 @@ void NodeOperationBuilder::add_output_buffers(NodeOperation *operation, NodeOper
 	
 	/* if no write buffer operation exists yet, create a new one */
 	if (!writeOperation) {
-		writeOperation = new WriteBufferOperation();
+		writeOperation = new WriteBufferOperation(operation->getOutputSocket()->getDataType());
 		writeOperation->setbNodeTree(m_context->getbNodeTree());
 		addOperation(writeOperation);
 		
@@ -534,7 +534,7 @@ void NodeOperationBuilder::add_output_buffers(NodeOperation *operation, NodeOper
 		if (&target->getOperation() == writeOperation)
 			continue; /* skip existing write op links */
 		
-		ReadBufferOperation *readoperation = new ReadBufferOperation();
+		ReadBufferOperation *readoperation = new ReadBufferOperation(operation->getOutputSocket()->getDataType());
 		readoperation->setMemoryProxy(writeOperation->getMemoryProxy());
 		addOperation(readoperation);
 		
diff --git a/source/blender/compositor/intern/COM_OpenCLDevice.cpp b/source/blender/compositor/intern/COM_OpenCLDevice.cpp
index c5b663d2aef..7fc4fd38abd 100644
--- a/source/blender/compositor/intern/COM_OpenCLDevice.cpp
+++ b/source/blender/compositor/intern/COM_OpenCLDevice.cpp
@@ -24,6 +24,18 @@
 #include "COM_WorkScheduler.h"
 
 typedef enum COM_VendorID  {NVIDIA = 0x10DE, AMD = 0x1002} COM_VendorID;
+const cl_image_format IMAGE_FORMAT_COLOR = {
+	CL_RGBA,
+	CL_FLOAT
+};
+const cl_image_format IMAGE_FORMAT_VECTOR = {
+	CL_RGB,
+	CL_FLOAT
+};
+const cl_image_format IMAGE_FORMAT_VALUE = {
+	CL_R,
+	CL_FLOAT
+};
 
 OpenCLDevice::OpenCLDevice(cl_context context, cl_device_id device, cl_program program, cl_int vendorId)
 {
@@ -72,6 +84,21 @@ cl_mem OpenCLDevice::COM_clAttachMemoryBufferToKernelParameter(cl_kernel kernel,
 	return COM_clAttachMemoryBufferToKernelParameter(kernel, parameterIndex, offsetIndex, cleanup, inputMemoryBuffers, (ReadBufferOperation *)reader);
 }
 
+const cl_image_format* OpenCLDevice::determineImageFormat(MemoryBuffer *memoryBuffer)
+{
+	const cl_image_format *imageFormat;
+	int num_channels = memoryBuffer->get_num_channels();
+	if (num_channels == 1) {
+		imageFormat = &IMAGE_FORMAT_VALUE;
+	} else if (num_channels == 3) {
+		imageFormat = &IMAGE_FORMAT_VECTOR;
+	} else {
+		imageFormat = &IMAGE_FORMAT_COLOR;
+	}
+
+	return imageFormat;
+}
+
 cl_mem OpenCLDevice::COM_clAttachMemoryBufferToKernelParameter(cl_kernel kernel, int parameterIndex, int offsetIndex,
                                                                list<cl_mem> *cleanup, MemoryBuffer **inputMemoryBuffers,
                                                                ReadBufferOperation *reader)
@@ -80,12 +107,9 @@ cl_mem OpenCLDevice::COM_clAttachMemoryBufferToKernelParameter(cl_kernel kernel,
 	
 	MemoryBuffer *result = reader->getInputMemoryBuffer(inputMemoryBuffers);
 
-	const cl_image_format imageFormat = {
-		CL_RGBA,
-		CL_FLOAT
-	};
+	const cl_image_format *imageFormat = determineImageFormat(result);
 
-	cl_mem clBuffer = clCreateImage2D(this->m_context, CL_MEM_READ_ONLY | CL_MEM_COPY_HOST_PTR, &imageFormat, result->getWidth(),
+	cl_mem clBuffer = clCreateImage2D(this->m_context, CL_MEM_READ_ONLY | CL_MEM_COPY_HOST_PTR, imageFormat, result->getWidth(),
 	                                  result->getHeight(), 0, result->getBuffer(), &error);
 
 	if (error != CL_SUCCESS) { printf("CLERROR[%d]: %s\n", error, clewErrorString(error));  }
diff --git a/source/blender/compositor/intern/COM_OpenCLDevice.h b/source/blender/compositor/intern/COM_OpenCLDevice.h
index 94df2f2b44c..f8a8841ef47 100644
--- a/source/blender/compositor/intern/COM_OpenCLDevice.h
+++ b/source/blender/compositor/intern/COM_OpenCLDevice.h
@@ -94,6 +94,12 @@ public:
 	 */
 	void execute(WorkPackage *work);
 
+	/**
+	* @brief determine an image format
+	* @param memorybuffer
+	*/
+	static const cl_image_format* determineImageFormat(MemoryBuffer *memoryBuffer);
+
 	cl_context getContext() { return this->m_context; }
 
 	cl_command_queue getQueue() { return this->m_queue; }
diff --git a/source/blender/compositor/intern/COM_WorkScheduler.cpp b/source/blender/compositor/intern/COM_WorkScheduler.cpp
index e1016731c7f..8445dee5ae4 100644
--- a/source/blender/compositor/intern/COM_WorkScheduler.cpp
+++ b/source/blender/compositor/intern/COM_WorkScheduler.cpp
@@ -196,7 +196,7 @@ void WorkScheduler::schedule(ExecutionGroup *group, int chunkNumber)
 		BLI_thread_queue_push(g_cpuqueue, package);
 	}
 #else
-	BLI_thread_queue_push(cpuqueue, package);
+	BLI_thread_queue_push(g_cpuqueue, package);
 #endif
 #endif
 }