Sobel Edge Detector

A Sobel Edge Detection Filter written in OpenCL and C++. The library makes use of FreeImage to load and save image files.

Example

Here's what the library does:

Usage

The RunSobel.cpp gives an example of how to use the library. It is outlined here:

#include "SobelFilter.h"
...

std::string Path = "myimage.bmp";

// Declare the edge detector
SobelFilter EdgeDetector;

// Load the image from the file
EdgeDetector.LoadImage(Path.c_str());

// Run it
EdgeDetector.Run();

// Save the edge detected image
// Use .bmp to make working with FreeImage easy
std::string OutputPath = "sobel_" + Path + ".bmp";
EdgeDetector.SaveImage(OutputPath.c_str());

And that's it. You'll get a file called sobel_myimage.bmp.bmp as output.

I've included a common folder in the repo. It includes the OpenCL and FreeImage libraries needed to run the filter.

There is also commented out code for the OpenCL 2.0 versions of the commands that are now deprecated.

Command Line Usage

See the run.sh file on how to compile and run the code

g++ -c SobelFilter.cpp -lOpenCL -Icommon/OpenCL/include -Icommon/FreeImage/include -std=c++11 -o SobelFilter.a
g++ RunSobel.cpp SobelFilter.a common/FreeImage/lib/linux/x86_64/libfreeimage.a -lOpenCL -Icommon/OpenCL/include -std=c++11 -o sobel

./sobel lena.bmp

This first compiles the SobelFilter library, then it compiles the RubSobel command line program. Once it is compiled just call sobel and the path to the file you want to run it against.

Revision History

1.1.1

Updated local work size to accomodate non-square or evenly divisible image sizes.

1.1.0

Fixed the RGB to grey scale conversion.

1.0.0

Initial release.