# DanceMirror - Dance Practice Comparison App
# https://dance-practice.pages.dev/
# Last Updated: 2026-01-06

## Overview

DanceMirror is a free web application for comparing dance videos side by side. It helps dancers improve their skills by comparing their movements with instructors or professional dancers.

## Key Features

### 1. Side-by-Side Video Comparison
- Display two videos simultaneously (Teacher and Self)
- Synchronized playback with adjustable timing offset
- Mirror/flip video horizontally
- Zoom and position adjustment

### 2. AI Skeleton Detection (Bone Visualization)
- Uses MediaPipe Pose for real-time skeleton detection
- Detects 33 body landmarks
- Teacher skeleton: Yellow/Amber color
- Self skeleton: Green/Emerald color
- Spine, shoulders, hips, arms, and legs visualization
- Pre-analysis mode for smooth playback

### 3. Webcam Recording
- Record yourself dancing using PC webcam
- 720p resolution, 30fps
- 3-second countdown before recording
- Recorded video automatically loads for comparison

### 4. Sync Recording Mode
- Record while watching teacher's video
- Teacher video plays simultaneously with recording
- Perfect timing alignment automatically
- Auto-stop when teacher video ends

### 5. Playback Controls
- Speed adjustment: 0.25x, 0.5x, 0.75x, 1x, 1.5x, 2x
- Frame-by-frame stepping
- 10-second skip forward/backward
- Loop playback
- Keyboard shortcuts support

## Technical Specifications

- **Platform**: Web Browser (Chrome, Edge recommended)
- **Framework**: Hono (TypeScript)
- **Hosting**: Cloudflare Pages
- **AI Library**: MediaPipe Pose
- **Privacy**: All processing done locally in browser
- **No Server Upload**: Videos never leave user's device
- **Offline Support**: Works without internet after initial load

## Use Cases

1. **K-POP Dance Practice**: Learn choreography from music videos
2. **Hip-Hop/Street Dance**: Compare freestyle moves
3. **Ballet**: Check posture and form
4. **Fitness/Yoga**: Verify exercise form
5. **Dance Instruction**: Teachers can review student progress
6. **Sports Training**: Analyze athletic movements

## Target Users

- Dance beginners learning choreography
- Intermediate dancers improving technique
- Dance instructors reviewing students
- Fitness enthusiasts checking form
- Athletes analyzing movements
- Content creators making dance videos

## How to Use

1. Open https://dance-practice.pages.dev/app
2. Upload teacher/reference video (drag & drop or click)
3. Upload your video OR use "Record with Teacher" for sync recording
4. Adjust timing offset if needed
5. Use slow motion (0.25x-0.5x) for detailed comparison
6. Enable skeleton display for movement visualization

## Keyboard Shortcuts

- Space: Play/Pause
- Left/Right Arrow: Skip 10 seconds
- Comma/Period: Step 1 frame
- F: Fullscreen toggle

## Privacy & Security

- **100% Client-Side Processing**: All video processing happens in your browser
- **No Data Collection**: We don't collect any personal data or videos
- **No Account Required**: Use immediately without registration
- **No Cookies**: No tracking or analytics cookies

## FAQ

Q: Is DanceMirror free?
A: Yes, completely free with no hidden costs or premium features.

Q: Are my videos uploaded to a server?
A: No, all videos are processed locally in your browser. Nothing is uploaded.

Q: What is skeleton/bone detection?
A: AI technology that detects body joints and visualizes them as connected lines, making it easier to compare body movements.

Q: Does it work on mobile?
A: It works but PC is recommended for better comparison experience.

Q: What video formats are supported?
A: All formats supported by your browser (MP4, WebM, MOV, etc.)

## Contact & Support

- Website: https://dance-practice.pages.dev/
- Developer: TOKYO DEFENSE

## Related Keywords

ダンス練習, 動画比較, ダンスアプリ, 振付練習, ダンスレッスン, スロー再生, フォームチェック, 骨格検出, ボーン表示, AI分析, Webカメラ録画, K-POP, ヒップホップ, バレエ, ストリートダンス, MediaPipe, dance practice, video comparison, choreography learning, dance tutorial, skeleton detection, pose estimation

## Version History

- v1.0.0 (2026-01): Initial release with all core features
  - Side-by-side video comparison
  - AI skeleton detection
  - Webcam recording
  - Sync recording mode
  - Playback controls

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For human-readable documentation, visit: https://dance-practice.pages.dev/