mvimage.sh

#!/bin/bash

# This script converts .heic files to .jpg files. The actual file encoding
# is checked, so that if the file is renamed correctly, it will be named 
# and converted properly.
#
# Instructions:
#
# From the folder that contains the image files you want to convert...
#
# Reads all files in the current folder and renames them to lowercase.
#
# And also...
#
# Checks the encoding, and if the encoding is image/heic and file
# extension is NOT .heic, the file name is given a .heic extension.
# 
# Then...
#
# Checks the encoding, and if the encoding is image/jpeg and file
# extension is NOT .jpg, the file name is given a .jpg extension.
#
# Then...
# 
# All .heic files are converted to .jpg image files.
#
# Only files with encoding of image/heic and image/jpeg are processed,
# all other files are ignored.
#
# The --live switch will actually change files.
# $ ~/bin/mvimage.sh [--live]

live=0
if [[ $1 == --live ]]; then
  live=1
fi

if [[ $live -eq 1 ]]; then
  echo Running in live mode...
else
  echo Running in pretend mode...
fi

shopt -s nocasematch

for file in *.*; do
  new_filename=$file
  
  # Check to see if filename has spaces...
  pattern=" |'"
  if [[ $file =~ $pattern ]]; then
    # Remove spaces from filenames...
    new_filename="${file// /_}"
    new_filename=$(echo "$new_filename" | tr '[:upper:]' '[:lower:]')
    while [[ -f "$new_filename" ]]; do
     echo "$new_filename exists, trying _$new_filename..."
     new_filename="_$new_filename"
    done
  fi

  # Make the filename lowercase and rename the file...
  new_filename=$(echo "$new_filename" | tr '[:upper:]' '[:lower:]')

  # Extract file encoding information...
  file_encoding_info=$( file -I $new_filename )

  # Split the filename so we can use the filename and check the extension
  # against the file encoding...
  filename=$(basename -- "$new_filename")
  extension="${filename##*.}"
  extension="$(echo $extension | tr '[:upper:]' '[:lower:]')"
  filename="${filename%.*}"

  IFS=' ' read -r -a encoding_array <<< "$file_encoding_info"

  file_encoding="${encoding_array[1]}"

  # Rename the file
  if [[ ! $file_encoding == "image/jpeg;" ]] && [[ ! $file_encoding == "image/heic;" ]]; then
    echo "Ignoring file $file -> encoding is not image/jpeg or image/heic."
  else
    if [[ $live -eq 1 ]]; then
      echo "mv $file $new_filename"
      mv "$file" $new_filename
    else
      echo "Pretend -> mv $file $new_filename"
    fi
  fi

  if [[ $extension != ".heic" ]] && [[ $file_encoding == "image/heic;" ]]; then
  	heic_filename="$filename.heic"
  	if [[ $live -eq 1 ]]; then
  	  echo "mv $file $heic_filename"
      mv $file $heic_filename
  	else
  	  echo "Pretend -> mv $file $heic_filename"
  	fi
  fi

  if [[ $file_encoding == "image/jpeg;" ]] && [[ $extension != ".heic" ]] && [ $extension != "jpg" ]; then
  	if [[ $live -eq 1 ]]; then
  	  echo "mv $file $filename.jpg"
      mv $file "$filename.jpg"
  	else
  	  echo "Pretend -> mv $file $filename.jpg"
  	fi
  fi
done

if [[ $live -eq 1 ]]; then
  mogrify -format jpg *.heic && rm *.heic
else
  echo "Pretend -> mogrify -format jpg *.heic && rm *.heic"	
fi