Rate and Complexity-Aware Coding Scheme for Fixed-Camera Videos Based on Region-of-Interest Detection

Abstract

This paper presents a rate and complexity-aware coding scheme for fixed-camera videos that are designed to improve image quality in Regions of Interest (ROI) by prioritizing the encoding of such regions through the use of a modified mode decision equation. ROIs are defined in this work as faces, with the application of a face detection algorithm. Background Images (BGI) are also detected with the aim of reducing bitrate in coding blocks belonging to these areas. Finally, the proposed scheme also applies an early decision method intending to reduce coding time. Experimental results show that the proposed scheme is capable of improving the image quality in 0.99 dB in ROIs, reaching an improvement of 1.16 dB in the best case. Also, the scheme achieves an encoding time reduction of up to 55% (about 5.5%, on average) with unexpressive variations in the required bitrate.