TrimSync (trimsy) is a command-line video speed editor written in the Odin programming language. It analyzes a video's audio track to automatically detect silent segments and can speed them up (or remove them entirely via jump-cuts), saving you time in post-production.

• Silence Detection: Automatically identifies quiet parts in your audio track.
• Speed Adjustment: Set distinct speeds for sounded segments vs. silent segments (e.g., normal speed for speaking, 5x speed for pauses).
• Jump Cuts: Completely skip/remove silence for tight editing.
• Safety Margins: Add padding around spoken segments to ensure words aren't abruptly cut off.
• Presets: Comes with built-in presets for lectures, podcasts (gentle), aggressive saving, and raw jump cuts.
• Analysis Mode: Check timing breakdowns and get suggestions on configurations without having to wait for the video to re-render.

• Odin compiler (for building from source)
• FFmpeg installed and accessible in your system's PATH.

To build the executable, simply run:

odin build . -out:trimsy -o:speed

# On windows add -extra-linker-flags
odin build . -out:trimsy.exe -o:speed -extra-linker-flags:"/LIBPATH:C:\path\to\your\ffmpeg-shared\lib"
# You'll also need to copy avutil-##.dll avcodec-##.dll avformat-##.dll and swresample-#.dll near your .exe
# Or add the ffmpeg-shared/bin directory to your path

trimsy <input_file> [options]

  -o, --output <file>          Output file (default: input_trimmed.ext)
  -t, --threshold <0.03>       Silent threshold (0.0–1.0)
  -s, --sounded-speed <1.0>    Speed multiplier for sounded segments
  -ss, --silent-speed <5.0>    Speed multiplier for silent segments
  --skip, --jumpcut            Remove silent segments entirely (jump cut)
  -m, --margin <1>             Frames of safety margin around speech
  -p, --preset <name>          Use a preset (see below)
  --analyze                    Analyze only — show timing breakdown, no output
  --help, -h                   Show help

Process a video with default settings:

./trimsy lecture.mp4

Use a preset:

./trimsy tutorial.mp4 -p jumpcut

Test threshold behavior (Analysis mode):

./trimsy interview.mov --analyze -t 0.05

Custom speed overrides:

./trimsy meeting.mp4 -ss 8 -s 1.25 -m 2

jumpcutter by carykh

YT video: Automatic on-the-fly video editing tool!