Holding down the left mouse button on an image allows you to scroll the image. The mouse wheel will scroll the image up and down. Clicking the middle mouse button will toggle the auto zoom on/off. Hold down the Control key, then either use the mouse wheel to zoom in and out or left click to zoom in and right click to zoom out. The mouse wheel, used while holding down the Alt key, will scroll the image horizontally. Double-clicking on an image toggles Browse mode. By default, the mouse wheel will scroll the image up and down. But, this can be configured to browse the images in the current directory instead. Hold down the left mouse button over an image, then click the right button to go to the next image. Hold down the right button, then click the left button to load the previous image.