Understanding in-loop filtering in the HEVC video standard

Mihir Mody, Texas Instruments
EDN (June 21, 2013)

High Efficiency Video Coding (HEVC) is a video compression standard, a successor to H.264/MPEG-4 AVC (Advanced Video Coding), jointly developed by the ISO/IEC Moving Picture Experts Group (MPEG) and ITU-T Video Coding Experts Group (VCEG) as ISO/IEC 23008-2 MPEG-H Part 2 and ITU-T H.265. HEVC promises half bit-rate compared to current de-facto standard H.264 at a similar video quality and is expected to be deployed in a wide variety of video applications ranging from cell phones, broadcast, set-top box, video conferencing, video surveillance, automotive, etc.

The figure below shows the block diagram of the HEVC Video decoder with loop filtering, as shown with loop filtering highlighted. As shown, it is a cascading of two stages - namely de-blocking filtering (DBLK) and Sample adaptive offset (SAO) filtering to remove blocking artifacts causing during video encoding. The next two sections describe these two stages in detail.

Click here to read more ...