jpg=""
count=`ls -1 *.jpg 2>/dev/null | wc -l`
if [ $count != 0 ]
then
echo jpg files found: $count ; jpg="yes"
fi

#!/bin/bash

shopt -s nullglob

for ext in jpg png gif; do
  files=( *."$ext" )
  printf 'number of %s files: %dn' "$ext" "${#files[@]}"

  # now we can loop over all the files having the current extension
  for f in "${files[@]}"; do
    # anything else you like with these files
  done

done

ls | awk -F . '{print $NF}' | sort | uniq -c | awk '{print $2,$1}'

exts=( *.jpg *.png *.gif ); printf "There are ${#exts[@]}" extensions;

extensions="jpg png gif"
for ext in $extensions; do
  c=$(find . -maxdepth 1 -iname "*.$ext" -print0 | tr -d -c "00" | wc -c)
  if [ $c -gt 0 ]; then
    echo "Found $c  *.$ext files"

    find . -maxdepth 1 -iname "*.$ext" -print0 | xargs -0 -r -n1 DOSOMETHINGHERE
    # or #  find . -maxdepth 1 -iname "*.$ext" -exec "ls" "-l" "{}" ";"
  fi
done

find -type f | sed -e 's/.*.//' | sort | uniq -c