GitHub - baturyilmaz/open-video-overview: Generate narrated videos from text with AI-generated images. Local alternative to NotebookLM's Video Overview.

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Open Video Overview

An open-source alternative to NotebookLM's Video Overview. Built with Mastra to create narrated videos from text using AI-generated images (Gemini Nano Banana Pro) and voice (ElevenLabs).

This was quickly built as an experiment. Expect rough edges.

Examples

Generated Video Examples

Example 1: Repository Explainer (Retro Style, 16:9)

Retro Style Example

Brief format video explaining this repository in retro visual style

Example 2: Why Are Planets Round? (Anime Style, 9:16)

Anime Style Example

Short-form vertical video in anime visual style

Mastra Workflow Playground

Mastra Workflow Playground

The interactive Mastra playground interface for running video generation workflows

What it does

  • Generates video storyboards from text content
  • Creates images using Gemini
  • Generates narration using ElevenLabs TTS
  • Supports 25+ visual styles (watercolor, anime, 3b1b, etc.)
  • Supports 16 languages
  • Outputs MP4 videos with narration and visuals

Prerequisites

  • Node.js 18+ and pnpm
  • ffmpeg and ffprobe (for video processing) 
    # macOS
brew install ffmpeg

# Ubuntu/Debian
sudo apt install ffmpeg
  • Google Generative AI API Key (Get one here)
  • ElevenLabs API Key (Get one here)

Installation

# Clone the repository
git clone https://github.com/baturyilmaz/open-video-overview.git
cd open-video-overview

# Install dependencies
pnpm install

# Configure environment variables
cp .env.example .env
# Edit .env with your API keys

Configuration

Create a .env file with your API keys:

GOOGLE_GENERATIVE_AI_API_KEY=your_google_api_key
ELEVENLABS_API_KEY=your_elevenlabs_api_key

Usage

Development Server

Start the Mastra development server with interactive playground:

Access the playground at http://localhost:4111

Video Generation Workflow

The videoGenerationWorkflow accepts:

Required Parameters:

  • content (string): Source content for the video
  • style (string): Visual style (see available styles below)
  • format (string): "explainer" or "brief"
  • aspectRatio (string): "16:9" or "9:16"

Optional Parameters:

  • language (string): ISO language code (default: "en")
  • customInstructions (string): Additional instructions for generation
  • narrativeVoiceId (string): ElevenLabs voice ID
  • narrativeStyle (string): Narrative tone (e.g., "casual", "professional", "storytelling")

Visual Styles

watercolor, anime, retro, whiteboard, classic, cinematic, isometric, flat, comic, neon, oil, sketch, papercut, popart, storybook, pixel, minimalist, infographic, documentary, gothic, pastel, 3b1b, corporate, presentation, tech

Output

Generated videos are saved to output/<project-name>-<timestamp>/:

  • images/ - AI-generated images
  • audio/ - Narration audio files
  • videos/ - Individual video clips
  • <title>-final.mp4 - Complete concatenated video

Development Commands

pnpm run dev          # Start Mastra dev server
pnpm run build        # Build the project
pnpm run typecheck    # Run TypeScript type checking
pnpm run lint         # Run ESLint
pnpm run format       # Format code with Prettier

Architecture

The videoGenerationWorkflow handles the complete pipeline:

  1. Generate storyboard from source content
  2. For each clip: create transcript, generate image, produce audio, combine into video
  3. Concatenate all clips into final video

Contributing

PRs welcome.

Credits

Inspired by NotebookLM's Video Overview.

License

MIT