'''Changes from mainline >--frame-luma-bias has been changed to --luminance-qp-bias, following mainline's implementation. (...)
Quality & Performance >--psy-rd can now be used with all tunes.
>--psy-rd has been optimized to slighly increase encoding speed.
>High quality svt-av1-psy psy-rd has been added, and is activated at --psy-rd>=0.6 while using presets 6 and slower. It can considerably increase the strength of psy-rd, greatly increasing visual quality at no rate cost. It's been implemented hrough some careful mode decision changes that occur when psy-rd influence is significant enough. The reason behind not implementing by default and limiting it to slower presets (<=P6) is that it has a non negligible speed penalty, which gets problematic for the fastest presets; it only provides it at higher psy-rd strengths, justifiying the limiting it to -psy-rd>=0.6.
>--spy-rd levels have been added for greater control over the visual tradeoff that spy-rd pathways provide. The available levels are 0/1/2: 0 is default, with spy-rd disabled. 1 is fully enabled spy-rd (intra mode decision sharpness and interpolation sharpness modifications) and 2 is partially enabled spy-rd (interpolation sharpness modifications only).
>--sharp-tx 1 --psy-rd 0.5 has been made default to increase high fidelity encoding performance.
