Interpolation Of The Dc Component Of Coded Images Using A Rational Filter

In this paper, the problem of the interpolation of the DC components of JPEG or MPEG-coded images is addressed, and the use of nonlinear interpolators is proposed which are able to accurately reconstruct the images yielding both sharp details and low blocking artifacts. 1. INTRODUCTION In the recent years there has been an increased interest in image and video compression techniques, due to the large use of this kind of data in multimedia applications. Generally, both single images and image sequences are coded using techniques which are based on the DCT, which is applied blockwise, and a different treatment is given to the DC and the AC components of the transformed blocks. When the channel has limited bandwidth or is very busy, it may be useful for the receiver to be able to provide a rough reconstruction of the images when only part of the data has been received; this may be important, e.g., when browsing a database, or during data pre-selection or temporal segmentation of a seque..