An Android application for peer-to-peer communication and multimedia processing between devices, featuring Bluetooth serial communication, multi-protocol networking (TCP/UDP/KCP), Pub/Sub messaging, GPU/CPU rendering, audio recording & analysis, sensor data collection, AI chat integration (DeepSeek), and an embedded HTTP file server.
| Category |
Technologies |
| Platform |
Android (API 21+, target 31) |
| Language |
Java, C++ (C++11) |
| Native |
JNI, CMake 2.8+, OpenGL ES 2.0, OpenSL ES, NDK 23 |
| Network |
UDP (Multicast), TCP, KCP (Reliable UDP), HTTP, Bluetooth |
| Media |
AudioRecord, AudioTrack, MediaExtractor, OpenGL ES, YUV↔RGB, PCM↔WAV |
| UI |
Material Design, ConstraintLayout, Custom Views, System Overlay |
| Build |
Gradle 7.x, CMake, NDK (ARM NEON optimizations) |
app/src/main/
├── java/com/tsymiar/device2device/
│ ├── activity/ # Activities (12)
│ │ ├── MainActivity # Splash screen → auto-navigate
│ │ ├── SelectActivity # Main dashboard (network, sensor, chat, files, Bluetooth)
│ │ ├── TextureActivity # Image/Video GPU & CPU rendering
│ │ ├── WaveActivity # Audio recording & real-time waveform + speech recognition
│ │ ├── GraphActivity # Sensor real-time data display
│ │ ├── SensorActivity # List all device sensors
│ │ ├── CommitActivity # Bluetooth serial communication (RFCOMM)
│ │ ├── ConnectActivity # Bluetooth discoverability & device scanning
│ │ ├── DevicesActivity # Paired & discovered Bluetooth devices list
│ │ ├── BuggerActivity # Bug report / email feedback
│ │ ├── MyGitActivity # Open project GitHub page
│ │ └── ThanksActivity # Acknowledgements page
│ ├── service/ # Background services (7)
│ │ ├── SubscribeService # Pub/Sub subscribe floating window
│ │ ├── PublishService # Pub/Sub publish floating window
│ │ ├── HttpFileService # Embedded HTTP file server (File & SAF modes)
│ │ ├── ToastNotificationService # Global floating toast notifications
│ │ ├── ReceiverService # Bluetooth data receive floating window
│ │ ├── WindowService # Generic text overlay floating window
│ │ ├── SaveDataService # Persist Bluetooth received data to file
│ │ └── Voice # Audio alert playback service
│ ├── acceleration/ # Sensor & Voice modules
│ │ ├── SensorFragment # Real-time accelerometer chart (Bézier-smoothed)
│ │ ├── DefaultFragment # Basic sensor chart variant
│ │ └── Voice # Over-acceleration warning (threshold: 7.0 m/s²)
│ ├── dialog/ # UI dialogs
│ │ ├── ChatBoxDialog # DeepSeek AI chat (Chat / Reasoner models)
│ │ └── FileMsgDialog # File transfer with progress & SAF file picker
│ ├── entity/ # Data entities (PubSubSetting, Receiver)
│ ├── event/ # Observer-pattern event system (EventHandle, EventNotify)
│ ├── utils/ # Utilities (Atom, MP4Header, WAVHeader, SoundRecord, WaveCanvas, HttpsRequest, Utils, etc.)
│ ├── view/ # Custom views (WaveSurface, WaveformsView)
│ └── wrapper/ # JNI native bridge (Callback, Network, View, Media, Time)
├── cpp/ # Native C++ code
│ ├── JniMethods.cpp/h # All JNI entry points
│ ├── bitmap/ # BMP image processing
│ ├── callback/ # Java↔C++ bidirectional callbacks
│ ├── convert/ # PCM↔WAV, YUV↔RGB format conversion
│ ├── display/ # GPU (EGL/GLES2) & CPU rendering
│ ├── message/ # Thread-safe message queue
│ ├── socket/ # UDP / TCP / KCP / FileMsg protocol
│ ├── scadup/ # Message queue library (tsymiar/scadup)
│ ├── test/ # Unit tests (FileMsgSocket)
│ ├── time/ # Timestamp utilities
│ └── utils/ # File utilities, logging, constants
| Feature |
Description |
| Device Scanning |
Scan for nearby Bluetooth devices |
| Pairing |
List paired devices and discover new ones |
| Serial Comm |
Bidirectional RFCOMM communication with directional control commands |
| Data Logging |
Auto-save received data to local file |
| Floating Window |
Receive data display in draggable system overlay |
| Feature |
Description |
| UDP Server |
Start a UDP multicast server to receive data |
| UDP Client |
Start a UDP multicast client to send data |
| TCP Server |
Start a TCP server to receive data |
| KCP |
KCP (Reliable UDP) protocol for low-latency transmission |
| Pub/Sub |
Subscribe & Publish messages via floating dialog windows |
| File Transfer |
Custom binary protocol with chunked transfer (64KB/chunk) and progress callback |
| HTTP Server |
Embedded HTTP server with HTML directory listing; supports SAF mode (Android 10+) |
| Feature |
Description |
| GPU Rendering |
Image/Video rendering via OpenGL ES (EGL/GLESv2) |
| CPU Rendering |
Software-based image/video decoding and display |
| Audio Recording |
16kHz PCM recording with real-time waveform visualization |
| Audio Playback |
Play WAV/MP4/OGG/MP3/AAC/AMR files with waveform analysis |
| Speech to Text |
Built-in speech recognition (STT) integration |
| Sensor Monitor |
Real-time accelerometer/gravity/linear acceleration data display |
| Feature |
Description |
| AI Chat |
DeepSeek API integration with Chat / Reasoner (Deep Think) models |
| Sensor Alert |
Automatic warning audio when acceleration exceeds 7.0 m/s² threshold |
| Feature |
Description |
| Event System |
Observer-pattern event broadcast for inter-component communication |
| Time Sync |
Native timestamp acquisition and synchronization |
| Global Toast |
Floating toast notification service (3s auto-dismiss) |
| One-Key Exit |
Global exit manager to terminate all activities and services |
| Component |
Version |
| Android SDK |
31 (compileSdk) / 21+ (minSdk) |
| Android NDK |
23.0.7599858 |
| Build Tools |
30.0.3 |
| Gradle |
7.x |
| CMake |
2.8+ |
| JDK |
8 or 11 |
| ABIs |
arm64-v8a, armeabi-v7a, x86_64 |
| C++ Standard |
C++11 (ARM NEON optimized) |
<uses-permission android:name="android.permission.BLUETOOTH" />
<uses-permission android:name="android.permission.BLUETOOTH_ADMIN" />
<uses-permission android:name="android.permission.BLUETOOTH_CONNECT" />
<uses-permission android:name="android.permission.BLUETOOTH_SCAN" />
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />
<uses-permission android:name="android.permission.RECORD_AUDIO" />
<uses-permission android:name="android.permission.INTERNET" />
<uses-permission android:name="android.permission.ACCESS_WIFI_STATE" />
<uses-permission android:name="android.permission.CHANGE_WIFI_MULTICAST_STATE" />
<uses-permission android:name="android.permission.SYSTEM_ALERT_WINDOW" />
<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
<uses-permission android:name="android.permission.READ_PHONE_STATE" />
<uses-permission android:name="android.permission.HIGH_SAMPLING_RATE_SENSORS" />
# Local build
./build.sh
# CI build (Azure Pipelines)
# See azure-pipelines.yml
This project uses Azure Pipelines for continuous integration on macos-latest. The pipeline:
- Checks out the main repo and
tsymiar/scadup submodule
- Copies scadup native library to
app/src/main/cpp/scadup/
- Installs Android SDK components (NDK 23, build-tools 30.0.3, platform 31)
- Sets up JDK 11 and builds with Gradle 7.0.2
- Produces debug APK for
arm64-v8a, armeabi-v7a, x86_64
MIT License
