x264 presets

      --preset <string>       Use a preset to select encoding settings [medium]
                                  Overridden by user settings.
                                  - ultrafast:
                                    --no-8x8dct --aq-mode 0 --b-adapt 0
                                    --bframes 0 --no-cabac --no-deblock
                                    --no-mbtree --me dia --no-mixed-refs
                                    --partitions none --rc-lookahead 0 --ref 1
                                    --scenecut 0 --subme 0 --trellis 0
                                    --no-weightb --weightp 0
                                  - superfast:
                                    --no-mbtree --me dia --no-mixed-refs
                                    --partitions i8x8,i4x4 --rc-lookahead 0
                                    --ref 1 --subme 1 --trellis 0 --weightp 1
                                  - veryfast:
                                    --no-mixed-refs --rc-lookahead 10
                                    --ref 1 --subme 2 --trellis 0 --weightp 1
                                  - faster:
                                    --no-mixed-refs --rc-lookahead 20
                                    --ref 2 --subme 4 --weightp 1
                                  - fast:
                                    --rc-lookahead 30 --ref 2 --subme 6
                                    --weightp 1
                                  - medium:
                                    Default settings apply.
                                  - slow:
                                    --b-adapt 2 --direct auto --me umh
                                    --rc-lookahead 50 --ref 5 --subme 8
                                  - slower:
                                    --b-adapt 2 --direct auto --me umh
                                    --partitions all --rc-lookahead 60
                                    --ref 8 --subme 9 --trellis 2
                                  - veryslow:
                                    --b-adapt 2 --bframes 8 --direct auto
                                    --me umh --merange 24 --partitions all
                                    --ref 16 --subme 10 --trellis 2
                                    --rc-lookahead 60
                                  - placebo:
                                    --bframes 16 --b-adapt 2 --direct auto
                                    --slow-firstpass --no-fast-pskip
                                    --me tesa --merange 24 --partitions all
                                    --rc-lookahead 60 --ref 16 --subme 11
                                    --trellis 2
      --tune <string>         Tune the settings for a particular type of source
                              or situation
                                  Overridden by user settings.
                                  Multiple tunings are separated by commas.
                                  Only one psy tuning can be used at a time.
                                  - film (psy tuning):
                                    --deblock -1:-1 --psy-rd <unset>:0.15
                                  - animation (psy tuning):
                                    --bframes {+2} --deblock 1:1
                                    --psy-rd 0.4:<unset> --aq-strength 0.6
                                    --ref {Double if >1 else 1}
                                  - grain (psy tuning):
                                    --aq-strength 0.5 --no-dct-decimate
                                    --deadzone-inter 6 --deadzone-intra 6
                                    --deblock -2:-2 --ipratio 1.1 
                                    --pbratio 1.1 --psy-rd <unset>:0.25
                                    --qcomp 0.8
                                  - stillimage (psy tuning):
                                    --aq-strength 1.2 --deblock -3:-3
                                    --psy-rd 2.0:0.7
                                  - psnr (psy tuning):
                                    --aq-mode 0 --no-psy
                                  - ssim (psy tuning):
                                    --aq-mode 2 --no-psy
                                  - fastdecode:
                                    --no-cabac --no-deblock --no-weightb
                                    --weightp 0
                                  - zerolatency:
                                    --bframes 0 --force-cfr --no-mbtree
                                    --sync-lookahead 0 --sliced-threads
                                    --rc-lookahead 0