Synthesis And Optimization Of The Exchangeable Region Of Natural Images

With the rapid development of digital media technology,people can easily obtain dig-ital image information,but also stimulate the development of image synthesis technology.While many image composition and synthesis techniques have been proposed,neither ex-isting work nor professional image editing softwares such as Adobe Photoshop^c?provide a program explicitly for the task of realistically swapping regions within a single image.In this paper,we present an easy-to-use image-editing tool explicitly for that purpose,named as PatchSwapper.Users can simply determine the centre and radius of a pair of candidate regions or specify arbitrary borders by sketches;then,the swapping step is automatically and optimally executed.A graph-based approach is designed to find the optimal borders of two irregular regions to avoid generating visible seams.We use this approach to handle both non-transformed and transformed patches.For non-transformed cases,we not only achieve realtime performance with CPU multi-thread implementation,we also provide a location recommendation algorithm to help users find the appropriate exchangeable areas.For trans-formed patches,our method searches for the optimal transformation to generate interesting appearance changes on both the source and target locations.A Poisson color blending is performed on the stitched patches in order to eliminate the unnatural seam accompanied the exchange.Overall the proposed approach is not only suitable for swapping image objects of any shapes but also for some other applications,e.g.,image completion and composition.We conduct extensive experiments using PatchSwapper.The results show that indeed large content variation can be obtained by simply swapping patch locations using our algo-rithm,with further input.From the data-side point of view,the research work also verifies our starting observation,i.e.,there often exists some interchangeable regions in a single in-put image that can be utilized for editing.After taking into account the transformation of patches,the quality and structural richness of the results are greatly enhanced.As a compar-ative study,we conduct the execution of one of state-of-the-art image synthesis algorithm:PatchTable,and validated that our method can achieve results with better-or-equal quality in a more convenient and efficient manner in consumer-level CPU.