Image Compressor Script

A command-line Dart script to recursively scan a directory for JPG and PNG image files, display them in a tree structure, and then resize and compress them to a specified output directory.

Features

  • Recursively scans a source directory (defaults to assets/).
  • Identifies .jpg, .jpeg, and .png image files.
  • Presents the found image files in a clear tree-like structure.
  • Requires user confirmation before starting the compression process.
  • Resizes images to a specified width and height.
  • Compresses JPG images with a configurable quality setting.
  • Supports PNG images (resized, but PNG is a lossless format, so quality setting applies only to JPG).
  • Saves compressed images to an output directory (defaults to output/), preserving the original subfolder structure.

Getting started

Prerequisites

  • Ensure you have the Dart SDK installed.
  • This script requires the image and path packages.

Installation

  1. Save the provided Dart code (from the previous turn) into a file, e.g., compress_script.dart, within your project directory (like the root of your Flutter project if you intend to compress its assets).

  2. Create a pubspec.yaml file in the same directory if you don't have one.

  3. Add the necessary dependencies to your pubspec.yaml:

    dependencies:
  image: ^4.1.7 # Use the latest version
  path: ^1.8.0  # Use the latest version

  4. Run dart pub get in your terminal from the directory containing pubspec.yaml and compress_script.dart.

Usage

  1. Run the script using the Dart VM:

    dart run flutter_assets_compresser

  2. The script will scan the directory specified by the inputDir variable (defaulting to ./assets).

  3. It will print a tree structure showing all found JPG and PNG image files.

  4. You will be prompted to confirm if you want to compress the found images.

  5. Type y and press Enter to proceed with the compression. Type anything else to cancel.

  6. The compressed images will be saved to the directory specified by the outputDir variable (defaulting to ./output), maintaining their relative paths from the input directory.

You can modify the inputDir, outputDir, width, height, and quality variables directly in the compress_script.dart file to customize the behavior.

// Example configuration section in compress_script.dart
void main(List<String> arguments) async {
  // --- Configuration ---
  const String inputDir = 'assets'; // Directory to scan
  const String outputDir = 'compressed_images'; // Directory to save output
  const int quality = 75; // Desired JPEG quality (0 to 100)

  // ... rest of the script
}

Libraries

flutter_assets_compresser