A Simple and High Performing Rate Control Initialization Method for H.264 AVC Coding Based on Motion Vector Map and Spatial Complexity at Low Bitrate

Yalin Wu,Sun-Woo Ko

doi:10.1155/2014/595383

Abstract

The temporal complexity of video sequences can be characterized by motion vector map which consists of motion vectors of each macroblock (MB). In order to obtain the optimal initial QP (quantization parameter) for the various video sequences which have different spatial and temporal complexities, this paper proposes a simple and high performance initial QP determining method based on motion vector map and temporal complexity to decide an initial QP in given target bit rate. The proposed algorithm produces the reconstructed video sequences with outstanding and stable quality. For any video sequences, the initial QP can be easily determined from matrices by target bit rate and mapped spatial complexity using proposed mapping method. Experimental results show that the proposed algorithm can show more outstanding objective and subjective performance than other conventional determining methods.

Highlights

In the last decade, multimedia data has been applied to communication, security, entertainment, and military
In order to obtain the optimal initial QP for the various video sequences which have different spatial and temporal complexities, this paper proposes a simple and high performance initial QP determining method based on motion vector map and temporal complexity to decide an initial QP in given target bit rate
The initial QP can be determined from matrices by target bit rate and mapped spatial complexity using proposed mapping method

Summary

Introduction

Multimedia data has been applied to communication, security, entertainment, and military. H.264/AVC includes an RC [8] which can be used to achieve optimal subjective quality given transmission bandwidth limit by regulating the encoding parameters. In RC, the optimal QP has been determined for every frame of video sequence. In JVT-G012 [9], the scheme of one-pass RC uses a linear MAD prediction model to solve the chicken-and-egg dilemma. The algorithm of JVT-G012 includes the process of initialization for RC. In this process, the initial QP is determined for IDR picture in a video sequence. The optimal MAD of IDR can be calculated using initial QP. The value of initial QP can be determined according to the number of bits per pixel (BPP) which depends on the target bit rate, frame rate, and image size in JVT-G012. The relatively large number of bits is used to represent

Methods

Results

Conclusion