1. An image-capturing device for removing an unwanted object from an image, comprising: an image-input module, for receiving a first image; an image-identifying module, for identifying at least a target-image and at least an unwanted object in the first image; an unwanted object processing module, for performing an unwanted object processing step to remove the unwanted object from the first image and generating a second image; and an output module, for outputting the first image skipping the unwanted object processing step or the second image after the unwanted object processing step.