A maximum a posteriori estimator for high resolution video reconstruction from MPEG video

With the plummeting cost of video capture equipment and the availability of free applications allowing MPEG encoding, hobbiests can now affordably capture and encode their home videos for storage and transmission in MPEG format. To produce a high-quality still image from this archived MPEG video, motion compensation must be applied to a number of video frames. A great deal of work has been done formulating this problem in the spatial domain, however, the classical spatial domain formulations are suboptimal for transform-coded video. Patti and Altunbasak (see Proc. IEEE Int. Conf. Image Processing, 1999) proposed a POCS solution that directly incorporates the transform domain quantization information by working with the compressed bit stream. We present an alternative maximum a posteriori (MAP) solution that not only incorporates quantization information, but can also impose additional blocking artifact reduction constraints. We apply this new formulation to MPEG compressed video and demonstrate its effectiveness.