convert video file to animated gif with ffmpeg

vid2gif.bat

@echo off
@setlocal
set infile=%1
set outfile=%2
shift & shift
set fps=10
set w=320
:loop
IF NOT "%1"=="" (
	IF "%1"=="-fps" (
		set fps=%2
		shift
	)
	IF "%1"=="-w" (
		set w=%2
		shift
	)
	shift
	GOTO :loop
)
:main
@set start_time="0:0"
@set filter1="[0:v]fps=%fps%,scale=%w%:-1:flags=lanczos,split=2[x][y]"
@set filter2="[y]palettegen[p]"
@set filter3="[x][p]paletteuse[z]"
@ffmpeg -v warning -ss %start_time% -i %infile% ^
	-lavfi "%filter1%;%filter2%;%filter3%" -map "[z]" ^
	-y %outfile%
@endlocal
@echo on

vid2gif.nu

def main [ src: path
	out: path = "out.gif"
	--width(-w): int = 320
	--fps: int = 10 
] {
	let filters = ([
		$"[0:v]fps=($fps),scale=($width):-1:flags=lanczos,split=2[x][y]"
		"[y]palettegen[p]"
		"[x][p]paletteuse[z]" ] | str collect ";")

	[-v warning -ss "0:0" -i $src -lavfi $filters -map "[z]" -y $out] | ^ffmpeg $in
}