shell/.local/bin/resize.sh

   1 #!/bin/bash
   2 set -e
   3
   4 if [[ "$#" -ne 2 ]] || ! [[ -e "$1" ]] ||\
   5                 ! [[ "$2" =~ ^[0-9]+[eEpPtTgGmMkKbB]?$ ]]; then
   6         echo "Usage: $0 FILE TGT" >&2
   7         echo "  TGT is in bytes. Allowed suffixes: bB,kK,mM,gG,tT,pP,eE" >&2
   8         echo "  The result will be outputted to stdout. The progress to stderr" >&2
   9         exit
  10 fi
  11
  12 TGT=${2::-1}
  13 case "$2" in
  14         *[eE]) TGT=$((TGT*1024));&
  15         *[pP]) TGT=$((TGT*1024));&
  16         *[tT]) TGT=$((TGT*1024));&
  17         *[gG]) TGT=$((TGT*1024));&
  18         *[mM]) TGT=$((TGT*1024));&
  19         *[kK]) TGT=$((TGT*1024));&
  20         *[bB]) ;;
  21         *) TGT=$2
  22 esac
  23
  24 ORIGTGT=$(stat --printf="%s" "$1")
  25 printf "Original: % 20d\n" $ORIGTGT >&2
  26 printf "Target  : % 20d\n" $TGT >&2
  27 if [[ "$TGT" -ge "$ORIGTGT" ]]; then
  28         echo "TGT is already bigger than the original size" >&2
  29         exit
  30 fi
  31
  32 ORIG=$(identify "$1" | grep -oP '[0-9]+(?=x[0-9]+\+[0-9]+\+[0-9]+)')
  33 STEP=$((ORIG/2))
  34 PREV=0
  35 CUR=$ORIG
  36 D=-1
  37 echo -n "Resize to: " >&2
  38 while true; do
  39         PREV=$CUR;
  40         CUR=$((CUR+D*STEP))
  41         STEP=$((STEP/2))
  42         if [[ $PREV -eq $CUR ]]; then break; fi
  43         if [[ $(convert "$1" -resize ${CUR}x jpg:- | wc -c) -ge $TGT ]];
  44         then D=-1; else D=1; fi
  45         echo -n "$CUR," >&2
  46 done
  47 echo -e "\b " >&2
  48 convert "$1" -resize "${CUR}x" jpg:-