Image Encoder Project

This image encoder convert collections of images into compressed video format with Android and CLI interfaces.

Overview

The Image Encoder Project provides for image-to-video conversion through three main components:

• Android Application: User-friendly interface for image selection, encoding configuration, and video playback
• Image Encoder Core: Modular core logic handling the image-to-video conversion
• CLI Tool: Command-line interface powered by Picocli for terminal-based encoding

Features

• Android app with image selection capabilities and encoding controls
• Modular architecture separating core logic from interfaces
• Command-line tool for automated batch processing
• Picocli integration for robust CLI argument handling
• Fat JAR generation via Shadow plugin
• In-app video playback capabilities

Project Structure

ec504_AndroidCV/
├── app/
│   ├── build.gradle.kts
│   └── src/
│       └── main/
│           ├── java/com/example/androidvideoencoder/
│           │   └── MainActivity.kt
│           ├── res/
│           │   ├── layout/
│           │   │   ├── activity_main.xml
│           │   │   └── item_image.xml
│           │   └── values/
│           │       └── strings.xml
│           └── AndroidManifest.xml
├── image-encoder-cli/
│   ├── build.gradle.kts
│   └── src/main/java/com/example/image_encoder_cli/
│       └── ImageEncoderCLI.java
├── image-encoder-core/
│   ├── build.gradle.kts
│   └── src/main/java/com/example/image_encoder_core/
│       └── ImageEncoder.java
└── gradle/

Technologies

Core Stack

• Kotlin and Java
• Gradle with Kotlin DSL
• Android SDK

Plugins

• Android Gradle Plugin
• Kotlin Android Plugin
• Shadow Plugin
• Picocli

Prerequisites

• JDK 8+
• Latest Android Studio
• Android NDK Installed
• Gradle 8.5
• Git

Installation

Clone the repository:

git clone https://github.com/yourusername/ec504_AndroidCV.git
cd ec504_AndroidCV

Setting Up the Gradle Wrapper

From terminal run:

gradle wrapper --gradle-version 8.5 --distribution-type all

Building the Project

Android Application

1. Open in Android Studio: Launch Android Studio and open the ec504_AndroidCV project.

2. Sync Gradle: Click on File > Sync Project with Gradle Files to resolve dependencies.

3. Build the Project: Navigate to Build > Build Project.

4. Run the App: Start an emulator, then click the Run button (This launches the app and shows two interfaces (Splash activity and Main activity)

CLI Tool

From Terminal

1. Navigate to the Project Root:

   cd ec504_AndroidCV

2. Build the CLI Module:

   • On Linux/Mac:

     ./gradlew :image-encoder-cli:shadowJar --rerun-tasks --info

   • On Windows:

     gradlew.bat :image-encoder-cli:shadowJar --rerun-tasks --info

   Note that we only provided pre-built libencoder_jni for x64 Linux or ARM macOS. If you want to run the CLI on Windows you'll need to go to the native library Repository and build the native .dll library following the guide and put it in the root folder of this project.

3. Locate the Generated JAR: After the build, the fat JAR will be located at:

   image-encoder-cli/build/libs/image-encoder-cli-1.0.0.jar
   

Note: This jar file does not ship with the native library counterpart, so you have to put the native library in appropriate places (e.g. libencoder_jni.dylib to /usr/lib/java) for the CLI to work. To see help information:

java -jar image-encoder-cli-1.0.0.jar --help

Intended usage of commandline below at the end of the project.

CLI Tool Usage

1. Ensure Java is Installed: Verify Java installation with:

   java -version

2. Run the JAR File: Navigate to the directory containing the JAR file:

   cd ec504_AndroidCV/image-encoder-cli/build/libs/

3. Execute the JAR with Required Arguments:

   java -jar image-encoder-cli-1.0.0.jar --input /path/to/input/images --output /path/to/output/video.mpeg1 --format mpeg1 --quality 80

   Parameters:

   • --input or -i: Path to the directory containing input JPEG images.
   • --output or -o: Desired output file path for the encoded video.
   • --format or -f: Video format (e.g., mpeg1, mpeg2, h264, hevc).
   • --quality or -q: Encoding quality (1-100).

   Example:

   java -jar image-encoder-cli-1.0.0.jar --input ./images --output ./videos/output_video.mpeg1 --format mpeg1 --quality 80

---