Video Uploading & Streaming System Design (YouTube, Netflix)
Introduction
Video platforms like YouTube and Netflix must handle massive video uploads, transcoding, storage, and global streaming. The system must deliver high-quality video with minimal buffering and support millions of concurrent viewers.
Problem Statement
How can we design a system that allows users to upload, store, and stream videos efficiently and reliably at scale?
System Requirements
- Support for large video uploads.
- Efficient transcoding to multiple formats and bitrates.
- Scalable storage and content delivery.
- Low-latency, high-quality streaming.
- Analytics and recommendations.
High-Level Design
The system consists of:
- Upload Service: Handles large file uploads, chunking, and resumable uploads.
- Transcoding Pipeline: Converts videos to multiple formats and resolutions.
- Storage: Stores original and transcoded videos (object storage, CDN).
- Streaming Service: Delivers video to users using adaptive bitrate streaming.
- Metadata and Analytics: Tracks views, engagement, and recommendations.
Key Components
- Chunked Uploads: Allows large files to be uploaded reliably.
- Distributed Transcoding: Scales video processing across many servers.
- Content Delivery Network (CDN): Caches and delivers video close to users.
- Adaptive Streaming: Adjusts video quality based on user bandwidth.
Challenges
- Storage Costs: Managing petabytes of video data.
- Transcoding Latency: Processing videos quickly for availability.
- Scalability: Handling spikes in uploads and views.
- Copyright and Moderation: Detecting and managing content.
Example Technologies
- Storage: Amazon S3, Google Cloud Storage.
- Transcoding: FFmpeg, custom pipelines.
- CDN: CloudFront, Akamai.
Conclusion
Video uploading and streaming at scale requires efficient pipelines, distributed storage, and adaptive delivery. By leveraging cloud infrastructure and CDNs, you can provide a seamless video experience to users worldwide.