Photo Gadget Pro is a shell extension that adds image editing options to Windows Explorer. It can rotate, resize, crop and rename images, add a caption and/or frame, apply different effects and filters (grayscale, invert colors, sepia, flip horizontal/vertical) and carry out format conversions.
To use the program simply select image files to work with in Explorer's window, right click the selection and choose an action from the context menu. Supported image file formats are BMP, TIFF, PNG, PCX, TGA and JPG with four levels of compression. You can set a target file size for resizing and conversions to JPG format and get lossless rotation on JPG files.