convert video to gif
require
ffmpeg(ffprobe)
gifski Highest-quality GIF encoder

Installed and add to environment variable
run powershell or cmd to check:

ffmpeg -version
ffprobe -version
gifski -V

• set pnglib (a folder to save extracted png file)
• drag video into this batch
• wait
• gif will save to same path as webm

gif, log, pnglib(if not set) will at same path as video
can be execute wherever this batch at

if you interrupted this batch you need to delete the lastest folder/file it created

you may want clean pnglib folder regularly
it can take massive disk space if you convert frequently

2020/06/02 rewritten
now it can execute anywhere, just drag file into it
in theory, this batch can handle all the video formats supported by ffmpeg
now support: webm, mp4, mkv
untest: webp, m4v, mov, avi, wmv, flv, hls, gif

lossless rotate gif (and other formats supported by magick)
require ImageMagick

• set angle
• drag gif into this batch