1. An image processing device, comprising: a first lens; a second lens, wherein the first lens and the second lens respectively captures at least one first image and at least one second image, and locations of the first lens and the second lens slightly differ; a first microphone; a second microphone, wherein the first microphone and the second microphone are respectively attached on the first lens and the second lens for capturing a first audio track and a second audio track; a memory unit, for storing an image stitching program; and a processor, for executing the image stitching program to perform the steps of: utilizing the image processing device to receive a first video file and a second video file, wherein the first video file comprises the at least one first image and the first audio track, and the second video file comprises the at least one second image and the second audio track; calculating delay time between a first acoustic feature of the first audio track and a second acoustic feature of the second audio track and synchronizing the first image and the second image according to the delay time; converting the synchronized first image and synchronized the second image into a first adjusted image and a second adjusted image, respectively; and performing an image stitching process on the first adjusted image and the second adjusted image to generate a stitched image.