ffmpeg how do i know what preset was used

Question

ffmpeg how do i know what preset was used?

How do I find it in mediainfo encode settings.

cpuid=0 / frame-threads=3 / no-wpp / no-pmode / no-pme / no-psnr / no-ssim / log-level=2 / input-csp=1 / input-res=1920x1080 / interlace=0 / total-frames=0 / level-idc=0 / high-tier=1 / uhd-bd=0 / ref=1 / no-allow-non-conformance / no-repeat-headers / annexb / no-aud / no-hrd / info / hash=0 / no-temporal-layers / open-gop / min-keyint=23 / keyint=250 / gop-lookahead=0 / bframes=3 / b-adapt=0 / b-pyramid / bframe-bias=0 / rc-lookahead=5 / lookahead-slices=0 / scenecut=0 / radl=0 / no-splice / no-intra-refresh / ctu=32 / min-cu-size=16 / no-rect / no-amp / max-tu-size=32 / tu-inter-depth=1 / tu-intra-depth=1 / limit-tu=0 / rdoq-level=0 / dynamic-rd=0.00 / no-ssim-rd / no-signhide / no-tskip / nr-intra=0 / nr-inter=0 / no-constrained-intra / strong-intra-smoothing / max-merge=2 / limit-refs=0 / no-limit-modes / me=0 / subme=0 / merange=57 / temporal-mvp / ...

Answer 1

It is -preset ultrafast

Using the encoder libx265 for H.265/HEVC video.

How to find the preset used

1. Use strings input.mp4 | grep x265 or mediainfo input.mp4 to get info as shown in your question.

2. Go to x265 documentation - Preset Options and refer to the table of parameters.

3. Yours has ref=1 and subme=0 which correlates with the ultrafast preset.

If your file details do not completely match any preset then additional options may have been used, or you are looking at a file created by a different encoder such as libx264 which has different settings.