The HEVC Test Model

Following the JCT-VC and MPEG meeting in October 2010, a Test Model for HEVC, HM1, was specified. The Test Model defines two broad categories of video coding tools, for (a) High Efficiency and (b) Low Complexity applications.

What's in the Test Model?

The main components are as follows:

Coding unit: Block sizes from 8x8 to 64x64 in tree structure
Transform: Quadtree structured block size from 4x4 to 32x32 samples
Intra prediction: Up to 34 intra prediction directions
Interpolation: 6- or 12-tap interpolation filter, down to 1/4-sample
Motion prediction: Advanced motion vector prediction
Entropy coding: CABAC or Low Complexity Entropy Coding (LCEC)
Loop filter: Deblocking filter or Adaptive Loop Filter (ALF)
Precision: Extended precision options

Many coding tools have been scheduled for further investigation and may be incorporated into the Test Model if they offer suitable compression gains.

How will it compare to H.264/AVC?

Current indications are that the new standard could provide 2x better video compression performance (i.e. around half the bitrate for a similar quality level) at the expense of significantly higher computational complexity, compared with H.264/AVC.

When will it be finished?

The timescale for completing the HEVC standard is as follows:
February 2012: Committee Draft (complete draft of standard)
July 2012: Draft International Standard
January 2013: Final Draft International Standard (ready to be ratified as a Standard)

Where can I find out more?

JCT-VC Meeting Documents : download JCTVC-C405 for a summary of the HEVC test model HM1.

November 2010