intra-refresh

[Steve Borho]

x264 has this feature which forces a column of macroblocks to be all intra; and I believe it restricts the intra modes to avoid some reference pixels. This column is swept across the frame over and over.

The goal of the feature is to avoid I-slice rate-control spikes by doing intra refresh constantly but only a bit at a time, and is extremely helpful for VBV quality.

The first step is to understand x264's feature very carefully and then figure out how it can be adapted to HEVC. The next step is to implement it. The last step is to validate it, and this might require tweaking a decoder to introduce artifacts and ensure they are corrected in due time.