doawk.sh

# Using awk we will find the bounding boxes from the detected points.
pushd $INPUT > /dev/null
ls -1 *.txt | \
    while read fname; do
	  TFM=$(awk -F, 'BEGIN {
                   minX=1000;
                   maxX=0;
                   minY=1000;
                   maxY=0;
                 }
                 $1 > maxX { maxX=$1 }
                 $1 < minX { minX=$1 }
                 $2 > maxY { maxY=$2 }
                 $2 < minY { minY=$2 }
                 END {
                   scale=90/sqrt((minX-maxX)*(minY-maxY));
                   width=maxX-minX;
                   height=maxY-minY;
                   cenX=width/2;
                   cenY=height/2;
                   printf "%s %s %s %s\n",
                     FILENAME,
                     (minX-cenX)*scale,
                     (minY-cenY)*scale,
                     (scale)*100
        }' $fname)
    
    awk -F, -v left=$(echo $TFM | cut -f2 -d' ') \
      -v top=$(echo $TFM | cut -f3 -d' ') \
      -v scale=$(echo $TFM | cut -f4 -d' ') '{
        s=scale/100;
        x=($1*s)-left;
        y=($2*s)-top;
        printf "%.0f,%.0f\n", x,  y}' $fname > $fname-scaled
    echo $TFM
    done > crop.tmp