Exposure mapping and dynamic thresholding for blending of multiple images using floating exposure

Abstract

Special blend operations for wide area-of-view image generation utilizing a 'floating auto exposure' scheme are described. Pixel values in the two images being stitched together are blended within a transition band around a 'seam.' identified in the overlap region between the images after changes in exposure and/or color saturation are accounted for. In some embodiments, changes in exposure and/or color saturation are accounted for through the use of one or more exposure mapping curves, the selection and use of which are based, at least in part, on a determined “Exposure Ratio” value, i.e., the amount that the camera's exposure settings have deviated from their initial capture settings. In other embodiments, the Exposure Ratio value is also used to determine regions along the seam where either: alpha blending, Poisson blending—or a combination of the two—should be used to blend in the transitional areas on each side of the seam.