Kineto

Cinematic video composition from the command line. Takes a screen recording and produces a polished video with a colored background, padding, rounded corners, drop shadow, and smooth auto-zoom — all in a single binary with no runtime dependencies.

Built on statically linked FFmpeg (libav*). Decodes H.264/VP8/HEVC, composites in RGBA, encodes to H.264 or HEVC via libx264/libx265. Runs on macOS, Linux, and Windows — no runtime dependencies on any platform.

Install

Download from Releases:

# macOS (Apple Silicon)
curl -sL https://github.com/onevarez/kineto-engine/releases/latest/download/kineto-darwin-arm64.tar.gz | tar -xz

# macOS (Intel)
curl -sL https://github.com/onevarez/kineto-engine/releases/latest/download/kineto-darwin-x64.tar.gz | tar -xz

# Linux (x64)
curl -sL https://github.com/onevarez/kineto-engine/releases/latest/download/kineto-linux-x64.tar.gz | tar -xz

# Windows (x64) — PowerShell
Invoke-WebRequest -Uri https://github.com/onevarez/kineto-engine/releases/latest/download/kineto-windows-x64.zip -OutFile kineto-windows-x64.zip
Expand-Archive kineto-windows-x64.zip -DestinationPath .

Or build from source:

# Requires static FFmpeg libraries — set FFMPEG_DIR to your install prefix
FFMPEG_DIR=/path/to/ffmpeg cargo build --release

Usage

kineto export -i recording.mp4 -o cinematic.mp4 \
  --bg-color "#0f0f23" \
  --padding 0.06 \
  --corner-radius 16 \
  --shadow \
  --codec h264 \
  --quality high

Examples

Basic composition

Dark background, rounded corners, drop shadow:

kineto export -i screen.mp4 -o output.mp4 \
  --bg-color "#1a1a2e" --padding 0.08 --corner-radius 12 --shadow

With auto-zoom

Pass a JSON file with zoom segments for smooth zoom-in/zoom-out on areas of interest:

kineto export -i screen.mp4 -o output.mp4 \
  --bg-color "#0f0f23" --padding 0.06 --corner-radius 16 --shadow \
  --zoom-segments-file zoom.json --zoom-easing smooth

Tight framing for social media

Minimal padding, large corners:

kineto export -i demo.mp4 -o social.mp4 \
  --bg-color "#000000" --padding 0.02 --corner-radius 24 --shadow \
  --codec h264 --quality high

Light background for documentation

kineto export -i tutorial.mp4 -o docs.mp4 \
  --bg-color "#f5f5f5" --padding 0.10 --corner-radius 8

Low quality for quick previews

kineto export -i raw.mp4 -o preview.mp4 \
  --bg-color "#0f0f23" --padding 0.06 --corner-radius 16 \
  --codec h264 --quality low

Options

Option	Default	Description
-i, --input	required	Input video file (H.264, VP8/WebM)
-o, --output	required	Output MP4 path
--bg-type	color	Background type (none, color)
--bg-color	#000000	Background hex color
--padding	0.08	Padding as fraction of canvas (0.0–0.4)
--corner-radius	12	Corner radius in pixels
--shadow	off	Enable drop shadow
--codec	hevc	Video codec (h264, hevc)
--quality	high	Encoding quality (low, medium, high)
--zoom-segments-file	none	Path to zoom segments JSON
--zoom-easing	smooth	Easing type (smooth, snappy, cinematic, spring)

Zoom Segments Format

[
  {
    "start_time": 2.5,
    "end_time": 5.0,
    "zoom_level": 2.0,
    "center_x": 0.3,
    "center_y": 0.6,
    "easing": "smooth",
    "hold_duration_secs": 1.5
  }
]

Each segment defines a time range where the camera zooms into a region. center_x and center_y are normalized coordinates (0.0–1.0) relative to the video frame. The zoom transitions in over 0.35s, holds, then transitions out over 0.35s.

Easing types:

Type	Feel	Math
smooth	Professional, calm	Cubic hermite: t²(3-2t)
snappy	Fast settle, energetic	Ease-out cubic: 1-(1-t)³
cinematic	Dramatic, slow edges	Ease-in-out quintic
spring	Playful, bouncy	Damped spring with ~5% overshoot

How It Works

Kineto processes each frame through a Rust-side composition pipeline:

1. Decode input via libavcodec (H.264, VP8)
2. Scale to the padded video dimensions (lanczos)
3. Composite in RGBA: background → shadow → video overlay → corner mask (anti-aliased)
4. Zoom (if segments provided): per-frame crop + scale with easing
5. Convert RGBA → YUV420P
6. Encode via libx264 with CRF quality control

The shadow is rendered at 1/4 resolution, blurred, and upscaled — fast even for 4K. Corner masks use 1.5px anti-aliasing at arc boundaries for smooth edges.

Platforms

Platform	Binary	Status
macOS arm64	kineto-darwin-arm64.tar.gz	Supported
macOS x64	kineto-darwin-x64.tar.gz	Supported
Linux x64	kineto-linux-x64.tar.gz	Supported
Windows x64	kineto-windows-x64.zip	Supported

License

GPL-2.0-or-later (x264/x265 static linkage)