Image Re-targeting Using Horizon Cues

With the rapid development of mobile hand held devices and computer networks, information, especially for image data, has become increasingly easy to obtain. Due to the limitations of practical conditions, especially for hand-held devices, the scenes within the images are of certain rotation angles. Although there exist some image editing tools, this is still hard for those without professional skills or knowledge. Meanwhile, In order to take out the image more pleasing, there are a lot of rules in photographic aesthetics to achieve this target. However, these rules are often only valid for before shooting, powerless for shot.From these viewpoints, the thesis tends to provide an effective method to re-target the images with trivial interaction. Retargeting is divided into two portions, tilt and salience adjustment. It's easy to think of the use of horizontal line to determine the horizon of the scene in the image. But the horizontal line cannot be expressed visually for computers; the proposed approach can circumvent this problem. The horizontal vanishing line be used to replace the horizontal line, and then the thesis employ the vanishing line detection method to determine the horizon and then adjust the angle of the scene to level the horizon. Besides, the image is thus retargeted to highlight the visual appearance by vanishing line at the same time, in order to accord with the rule of thirds.In addition to the image re-targeting, our method can also be applied on the task of distinguishing the image acquisition methods. For example, hand held phones typically don't have perfect level horizons, so the tilt of vanishing line can be used to determine which way of the shoot is.Finally, the thesis gives the experimental results of image re-targeting used the vanishing line, and the experimental results demonstrate the performance of our proposed method.