I need the result - a number.
That's what I found:
Code: Select all
alpha=`convert $f -resize 1x1 txt: | sed '1d' | sed 's/\([^)]*\).*/\1/' | sed 's/,/ /g' | awk '{print $NF}'`
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Code: Select all
alpha=`convert $f -resize 1x1 txt: | sed '1d' | sed 's/\([^)]*\).*/\1/' | sed 's/,/ /g' | awk '{print $NF}'`