image magick remove backgroud and set the backgroud transparent

blur.sh

#!/bin/bash
convert $1 -channel A -blur 1x65000 -level 50x100% \
-channel rgba $2

remove_backgroud.sh

#!/bin/bash

convert $1 -fuzz 5% \
-fill none -draw "matte 0,0 floodfill" \
-flop -draw "matte 0,0 floodfill" \
-flip -draw "matte 0,0 floodfill" \
-flop -draw "matte 0,0 floodfill" \
-flip -quality 100% $2

trim.sh

#!/bin/bash

convert $1 -fuzz 5% -trim $1