Client-Side H.264 Video Compression
Most modern smartphones record videos in massive 4K formats that can easily exceed several gigabytes for just a few minutes of footage. Attempting to share these over Discord (25MB limit), Email attachments (25MB limit), or Slack is often completely impossible without heavy compression.
What is Constant Rate Factor (CRF)?
Instead of manually guessing a bitrate metric, modern libx264 encoders utilize the CRF system to dynamically apply compression only where visually necessary. The default scale runs from 0 (lossless) to 51 (worst). A CRF value of 28 is universally considered the perfect balance for halving the file size without noticeable visual quality dropping on modern device screens.