摘要 |
A method and apparatus for image compression using temporal and resolution layering of compressed image frames (Figs. 8). In particular, layered compression (Fig. 8, items 81, 85, and 86) allows a form of modularized decomposition of an image that supports flexible application of a variety of image enhancement techniques (Fig. 2). Further, the invention provides a number of enhancements to handle a variety of video quality and compression problems (Fig. 7). Most of the enhancements are preferably embodied as a set of tools which can be applied to the tasks of enhancing image (Fig. 8.,item 82, 86) and compressing such images. The tools can be combined by a content developer in various ways, as desired, to optimize the visual quality and compression efficiency of a compressed data stream. Such tools include improved image filtering techniques, motion vector representation and determination, de-interlacing and noise reduction enhancements, motion analysis, imaging device characterization and correction, an enhanced 3-2 pulldown system (Fig. 1), frame rate methods for production, a modular bit rate technique, a multi-layer DCT structure (Fig. 20), variable length codin g optimization, an augmentation system for MPEG-2 and MPEG-4, and guide vector s for the spatial enhancement layer (Fig.8, item87). |