FFmpeg Optimizer

A lightweight video optimizer written in Python that uses FFmpeg to compress video files while keeping good visual quality.

Features

• Compress any FFmpeg-readable video to a MP4
• Quality-driven encoding via CRF (not fixed bitrate)
• Selectable encoding speed presets (ultrafast … veryslow)
• Sane streaming defaults:
  • H.264 (libx264), yuv420p, High profile, level 4.0
  • AAC audio, 96 kbps, stereo
  • +faststart for progressive playback
• Reports size before/after and the percentage saved
• Written in pure Python (standard library only)

Requirements

• Python 3.10+ (uses list[str] / Literal type syntax)
• FFmpeg available in PATH

Install FFmpeg:

# Debian / Ubuntu
sudo apt install ffmpeg

# Arch Linux
sudo pacman -S ffmpeg

git clone https://github.com/th0truth/ffmpeg-optimizer.git

cd ffmpeg-optimizer

Usage

python main.py -f <input> -o <output> [--crf N] [-p PRESET]

Example:

python main.py -f input.mkv -o out/input.mp4 --crf 20 -p slow

Options

Option	Default	Description
-f, --filename	—	Path to the source file (required)
-o, --output	—	Path for the optimized file (required)
--crf	23	Quality, lower is better (18–28)
-p, --preset	slow	Compression speed setting

Choosing a CRF

CRF	Result
18	Near-visually-lossless, largest file
20–23	Good quality, recommended range
26–28	Noticeably softer, smallest file

Slower presets produce smaller files at the same CRF, at the cost of encode time.

Exit Codes

Code	Meaning
0	Optimized successfully
1	Encoding failed

Released under the MIT License.