IMG -> SVG CLI (Portable) - on macOS and Linux

img2svg_cli.sh

#!/usr/bin/env bash

set -u

trap 'echo; echo "[EXIT] Interrupted."; exit 0' SIGINT

color() {
  case "$1" in
    red) printf '\033[0;31m%s\033[0m\n' "$2" ;;
    green) printf '\033[0;32m%s\033[0m\n' "$2" ;;
    yellow) printf '\033[1;33m%s\033[0m\n' "$2" ;;
    cyan) printf '\033[0;36m%s\033[0m\n' "$2" ;;
    bold) printf '\033[1m%s\033[0m\n' "$2" ;;
    *) printf '%s\n' "$2" ;;
  esac
}

line() {
  echo "------------------------------------------------------------"
}

handle_exit() {
  local input="$1"
  local normalized
  normalized=$(printf '%s' "$input" | tr '[:upper:]' '[:lower:]')

  case "$normalized" in
    q|quit|exit)
      echo
      color cyan "[EXIT] Bye."
      exit 0
      ;;
  esac
}

prompt() {
  local message="$1"
  local var_name="$2"
  local value
  read -r -p "$message" value
  handle_exit "$value"
  eval "$var_name=\"\$value\""
}

is_installed() {
  command -v "$1" >/dev/null 2>&1
}

install_tool() {
  local tool="$1"

  if is_installed "$tool"; then
    color green "[OK] $tool already installed."
    return
  fi

  color yellow "[..] $tool not found."

  if is_installed brew; then
    color yellow "[..] Installing with brew..."
    brew install "$tool"
  elif is_installed apt; then
    sudo apt update && sudo apt install -y "$tool"
  elif is_installed pacman; then
    sudo pacman -Sy --noconfirm "$tool"
  else
    color red "[ERROR] No supported package manager found."
    exit 1
  fi
}

show_header() {
  clear 2>/dev/null || true
  color cyan "============================================================"
  color cyan "                 IMG -> SVG CLI (Portable)                  "
  color cyan "============================================================"
  echo
  echo "Works on macOS and Linux"
  echo
  color yellow "Type q / quit / exit at any prompt"
  echo
}

show_menu() {
  line
  color bold "Conversion modes"
  echo "  1) Inkscape (experimental CLI)"
  echo "  2) Color vector (vtracer)"
  echo "  3) B/W vector (potrace)"
  echo "  4) Wrap image (no vector)"
  echo "  5) Exit"
  line
  echo
  prompt "Choose [1-5]: " MODE
}

ask_input() {
  prompt "Input file: " INPUT
  [[ -f "$INPUT" ]] || { color red "File not found"; ask_input; }
}

ask_output() {
  local default="${INPUT%.*}.svg"
  prompt "Output [$default]: " OUTPUT
  OUTPUT=${OUTPUT:-$default}
}

run_inkscape() {
  install_tool inkscape

  local actions="select-all;object-to-path;export-plain-svg;export-do"

  echo
  color cyan "[INKSCAPE CLI]"
  echo "inkscape \"$INPUT\" --actions=\"$actions\" --export-filename=\"$OUTPUT\""

  inkscape "$INPUT" --actions="$actions" --export-filename="$OUTPUT" || return 1
}

run_vtracer() {
  install_tool vtracer

  echo
  color cyan "[VTRACER]"
  vtracer --input "$INPUT" --output "$OUTPUT" --colormode color || return 1
}

run_potrace() {
  install_tool potrace
  install_tool imagemagick

  TMP=$(mktemp /tmp/img2svg.XXXX.pbm)

  echo
  color cyan "[POTRACE]"
  magick "$INPUT" -colorspace gray -threshold 55% "$TMP" || return 1
  potrace "$TMP" -s -o "$OUTPUT" || return 1

  rm -f "$TMP"
}

run_wrap() {
  install_tool inkscape
  inkscape "$INPUT" --export-type=svg --export-filename="$OUTPUT"
}

show_result() {
  echo
  line
  color bold "Result"
  ls -lh "$OUTPUT" 2>/dev/null || color red "No output"
  line
}

post_menu() {
  echo
  echo "1) Open"
  echo "2) Again"
  echo "3) Exit"
  prompt "> " NEXT

  case "$NEXT" in
    1) is_installed inkscape && inkscape "$OUTPUT" & ;;
    2) main ;;
    *) exit 0 ;;
  esac
}

main() {
  show_header
  show_menu

  case "$MODE" in
    1|2|3|4) ;;
    *) exit 0 ;;
  esac

  ask_input
  ask_output

  case "$MODE" in
    1) run_inkscape ;;
    2) run_vtracer ;;
    3) run_potrace ;;
    4) run_wrap ;;
  esac

  show_result
  post_menu
}

main