Fast intra block copy (IntraBC) search for HEVC screen content coding

Coding of screen content video is becoming important because of applications such as wireless displays, remote desktop, remote gaming, automotive infotainment, cloud computing, distance education etc. Video in these applications often has mixed content consisting of natural video, text and graphics in the same picture. Intra block copy (IntraBC) is a new coding tool being studied for the HEVC Range Extensions (RExt) standard. IntraBC is a block matching technique where in a Coding Unit (CU) is predicted as a displacement from already reconstructed block of samples from neighboring region in the same picture. IntraBC is very effective for screen content video since it removes redundancy from repeating patterns which typically occur in text and graphics regions. IntraBC provides a significant bit rate savings (up to 44%) for screen content sequences but at the cost of encoding time increase because of the search involved in Intra block matching. This paper presents fast encoding techniques for early skipping of IntraBC search which result in about 21% - 24% encoding time reduction for Intra coding.