C#, Image Processing / Automated Pattern Recognition

I have a need for an application or library that can locate a repeated pattern within a Bitmap with a provided threshold of accuracy / consistency and then extract this pattern(s) saving it to a high quality JPG file. The application will not be given the pattern to locate in the image initally so it will need to scan through the image and locate the sections that are similar without user assistance. The images are in color and are hi-res images. The pattern may be discovered in the color / texture of the image. Additional sample images will be provided.