Sub-pixel filter passes run over fixed block widths; frame / region planes are recycled
through a bounded pool (zeroed on reuse) instead of fresh calloc / munmap per frame; the
palette mode-info arrays (40 bytes per 4x4) exist only when screen content tools are allowed;
CDF adaptation is branch-free. Draft mode skips deblocking, CDEF and loop restoration of shown
frames that refresh no reference slot. Media-stack test: VP9 / HEVC / AV1 draft playback only
reaches draft requests, and an export afterwards is bit-exact with ffmpeg.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
