Rate-Distortion Optimized Bitstream Extractor for Motion Scalability in Wavelet-Based Scalable Video Coding

1.ABSTRACT:

         According to this article Motion scalability is designed to improve the coding efficiency of a scalable video coding framework, especially in the medium to low range of decoding bit rates and spatial resolutions. In order to fully benefit from the superiority of motion scalability, a rate-distortion optimized bit stream extractor, which determines  the optimal motion quality layer for any specific decoding scenario, is required. In this paper, the determination process first starts off with a brute force searching algorithm. Although guaranteed by the optimal performance within the search domain, it suffers from high computational complexities. Two properties, i.e., the monotonically non decreasing property and the unimodal property, are  then derived to accurately describe the rate-distortion behavior of motion scalability. Based on these two properties, modified searching algorithms are proposed to reduce the complexity (up to five times faster) and to achieve the global optimality, even for those decoding scenarios outside the search domain.

2.EXISTING SYSTEM:

                     A conventional nonscalable video codec, in which the decoder in an SVCF is restricted to certain decoding specifications, including different combinations of spatial, temporal, and quality layers. A video compression standard called Annex G, to H.264/MPEG-4 AVC with low efficient motion scalability. A method of lossless coding for the motion information was adapted and it is inefficient when decoding at lower resolutions.

3.PROPOSED SYSTEM:

                          A fully scalable motion model was proposed to solve the motion scalability problem from many aspects, along with tailored encoding techniques to minimize the coding overhead of scalability.

3.1Scalable Motion Model :

                          

3.2WSVC Framework :

                                  In this WSVC framework, successive temporal approximation and referencing (STAR), low band correction (LBC),

and resolution scalable wavelet difference reduction (RSWDR)

are adopted for realizing temporal, spatial and quality scalabilities,

respectively.

                       To  determine the optimal motion quality layer for any specific decoding scenario under a varying bit rate constrant  three approaches are proposed:

1)    Brute Force Method

2)    Model-Assisted Method

3)    Model-Based Method

                                                     The brute force method exercises an exhaustively searching algorithm among all possible motion quality layers. The model-assisted method is based on two properties derived directly from the exponential RD model in the general source coding theory and from the additive distortion model for motion scalability. The model-based method aims at improving the approaching speed of a blind method, such as the bisection method.

                      The purpose is to determine the best motion quality layer  for all possible target bit rates, as the decoding spatio-temporal

resolution is fixed.

4.HARDWARE REQUIREMENTS:

•         System                : Pentium IV 2.4 GHz.

•         Hard Disk            : 40 GB.

•         Floppy Drive       : 1.44 Mb.

•         Monitor                : 15 VGA Colour.

•         Mouse                 : Logitech.

•         Ram                     : 256 Mb.

5.SOFTWARE REQUIREMENTS:

•         Operating System       : - Windows XP Professional.

•         Front End                     : - Asp .Net 2.0.

•         Coding Language       : - Visual C# .Net.