Automatically detect and remove freeze/low-motion regions from videos using ffmpeg. Perfect for cleaning up screen recordings, presentation videos, or any footage with long static periods.

gem install speedrun

Or add to your Gemfile:

gem 'speedrun'

Requirements: Ruby >= 3.2.0, ffmpeg

Install ffmpeg:

# macOS
brew install ffmpeg

# Ubuntu/Debian
apt-get install ffmpeg

Basic usage:

speedrun trim input.mp4

This creates input-trimmed.mp4 with frozen segments removed.

speedrun trim INPUT [OUTPUT] [options]

Options:
  -n, --noise THRESHOLD        # Noise tolerance in dB (default: -70)
  -d, --duration SECONDS       # Minimum freeze duration in seconds (default: 1.0)
  --dry-run                    # Preview without processing
  -q, --quiet                  # Minimal output

Examples:
  speedrun trim video.mp4                                    # Creates video-trimmed.mp4
  speedrun trim video.mp4 output.mp4                         # Custom output name
  speedrun trim video.mp4 --noise -60                        # More sensitive detection
  speedrun trim video.mp4 --duration 2.0                     # Only remove freezes >= 2s
  speedrun trim video.mp4 --dry-run                          # Preview analysis only

The --noise parameter controls how sensitive freeze detection is to small changes in the video:

• Less negative values (like -60 dB) = More sensitive Detects freezes even when there's subtle motion or slight changes Use when you want to catch nearly-static sections

• More negative values (like -80 dB) = Less sensitive Only detects freezes when frames are nearly identical Use when you want to preserve sections with minimal motion

The default of -70 dB works well for most screen recordings. If you're getting false positives (motion incorrectly flagged as frozen), try -80 dB. If freezes are being missed, try -60 dB.

speedrun version                   # Show version
speedrun help                      # Show help

1. Detect: Uses ffmpeg's freezedetect filter to find frozen/low-motion segments
2. Analyze: Calculates which portions to keep vs. remove
3. Extract: Extracts active segments using ffmpeg
4. Stitch: Concatenates segments into final output

MIT License. See LICENSE or https://opensource.org/licenses/MIT