GitHub - joshribakoff/leetdreamer

🎬 LeetDreamer

"What if algorithm explanations didn't put you to sleep?"

A pipeline that generates narrated algorithm visualization videos. Because staring at code for 3 hours is less effective than watching a robot explain Two Pointers in 37 seconds.

🎥 See it in action

👆 Click to watch the generated video on YouTube

The Problem

• VisuAlgo: Great for bubble sort. Useless for LeetCode 42.
• YouTube tutorials: 20 minutes of "hey guys" before any content
• Static diagrams: Can't show when things happen
• Your own explanations: You understand it until you try to explain it

The Solution

Write a scene spec → Get a narrated video. That's it.

python build.py scenes/two_pointers/scene.json -v

Output: A video where a robot voice explains the algorithm while colorful boxes do the thinking for you.

How It Works

1. You write: A JSON scene spec with narration text and visualization state
2. Pipeline generates: TTS audio for each step
3. Pipeline renders: HTML animation timed to the audio
4. Pipeline merges: Audio + video = learning material

scene.json → 🎤 TTS → 🎨 Animation → 🎬 Final Video
                ↓
           Extract durations → Drive animation timing

The secret sauce: audio-first sync. Generate the voice track first, measure how long each phrase takes, then make the animation match. No more desynced disasters.

Installation

# Clone it
git clone https://github.com/joshribakoff/leetdreamer.git
cd leetdreamer

# Install dependencies
pip install playwright pydantic jinja2
playwright install chromium

# You'll also need FFmpeg somewhere

Creating a Scene

Scenes live in scenes/<name>/scene.json:

{
  "id": "my_algorithm",
  "title": "My Algorithm: O(magic)",
  "steps": [
    {
      "id": "step1",
      "narration": "First, we do the thing.",
      "state": {"highlight": "thing"}
    }
  ]
}

The narration becomes audio. The state drives the visualization. Simple.

Architecture

See ARCHITECTURE.md for the full nerd version. Key points:

• Adapters for everything (TTS, animation, recording, merging)
• Pydantic validation so your scene spec can't be wrong
• Jinja2 templates for HTML animations

Want to swap macOS say for OpenAI TTS? Change one adapter. Want Manim instead of HTML? Change one adapter. The dream is modularity.

Requirements

• Python 3.10+
• Playwright (for screen recording)
• FFmpeg (for audio/video merging)
• macOS (for the say TTS adapter... for now)

Status

🚧 Early days - The bones work, the flesh is still forming.

Currently renders: Two Pointers (Two Sum II)

Coming eventually: Sliding Window, Binary Search, DP visualizations, maybe your algorithm if you ask nicely.

Related Projects

LeetDeeper is the brain. LeetDreamer is the mouth. Together they form one very nerdy Voltron.

License

MIT - Do whatever you want, just don't blame me when the robot voice mispronounces "deque".