const CLEANUP_VBV_FRAMES: f64 = 4.0;Expand description
Frames of the target a constant-rate x264 session is given as its buffer while its cleanup
runs through the rate control, or CLEANUP_FRAME_S of its rate where that is more: in the
session’s buffer of a frame and a half x264’s row-level control prices a still screen’s whole
residual against the buffer and coarsens the rows it names a fine quantizer for, so a screen
of text at 2 Mbit/s at 1080p sat at 31 dB while the quantizer x264 planned read 19; in four
it reached 46 dB in five seconds with no frame over a budget and a half. A row finer than its
reference is priced at its whole intra cost against a slice’s share of the buffer: at 60 fps
four frames held a 1080p page at 0.5 Mbit/s at quantizer 30 and 25-35 dB, or at 51 after a
scroll, where 0.2 s reached 55.7 dB in 30 s.