Constant REFINE_FINER 

pub const REFINE_FINER: u32 = 0;

Quality index steps finer than the paint-over one VP8 codes a refined block at (FrameEncoder::refines): none, since a VP8 session’s paint-over quantizer already sits at the floor its bounds keep (VP8_DEFAULT_MIN_LEVEL), and 1080p text beside a video came out the same at 0, 3, and 6 steps finer (39.7 dB at 2 Mbit/s and 42.6 at 8 against 29.6 and 33.5 unrefined, where VP8’s cleanup of the still screen reaches 42.0). VP9 refines no block: in its screen mode a block whose source has not changed reads as static and is skipped whatever its segment’s quantizer, and refined, the same text came to 25.9 and 35.4 dB against 25.6 and 34.9, where VP9’s cleanup of the still screen reaches 37.7 and 51.1.