video_glitcher

Before	After

video_glitcher is a Java app built with Processing as a library. It extends PApplet, loads a video file, previews it fullscreen, applies glitch effects in real time, and exports the result as an MP4 in either live interactive mode or full-process mode.

Project site: krahd.github.io/video_glitcher

Current version: v1.1.3

The repository is self-contained and includes the Processing OpenGL jars needed for the P2D renderer, plus platform-specific video natives for macOS, Linux, and Windows. Export uses ffmpeg from your system PATH.

Install

Homebrew

On macOS Apple Silicon and Linux x86_64, install video_glitcher from the krahd/tap Homebrew tap:

brew tap krahd/tap && brew install krahd/tap/video_glitcher
video_glitcher

The Homebrew formula installs the matching prebuilt release bundle, adds ffmpeg plus openjdk automatically, and exposes the video_glitcher command. Windows should use the release ZIP instead.

Direct downloads

Latest release page:

• GitHub Releases

Latest release downloads:

• macOS Apple Silicon
• Linux x64
• Windows x64

For version-pinned downloads and release-specific details, open the release page for the tag you want.

Project Layout

• Formula/video_glitcher.rb: Homebrew formula snapshot synced to krahd/homebrew-tap
• src/tom/videoGlitcher/VideoGlitcher.java: main application source
• video_glitcher.pde: original Processing sketch version
• .vscode/launch.json: debug launch configs for video_glitcher on macOS, Windows, and Linux
• .vscode/tasks.json: build and run tasks for video_glitcher in VS Code
• .github/workflows/publish-homebrew-tap.yml: waits for release assets and updates the Homebrew tap formula from tagged releases or manual dispatch
• .github/workflows/release.yml: automated cross-platform release bundles
• lib/: bundled Processing, video, ControlP5, and Processing OpenGL libraries
• bin/: compiled class output
• packaging/homebrew/render_homebrew_formula.py: renders the asset-based Homebrew formula from release asset URLs and SHA-256 digests
• packaging/portable/: launcher scripts for the portable cross-platform bundle
• dist/: generated packaging output, ignored by git

Requirements

• Java 17 or newer
• VS Code with Java support
• Homebrew installs ffmpeg and openjdk automatically when you use brew tap krahd/tap && brew install krahd/tap/video_glitcher
• ffmpeg on your PATH if you want MP4 export
• Native video runtime files are already vendored for macos-aarch64, macos-x86_64, linux-amd64, and windows-amd64

Build

Build from the project root with:

javac -cp "lib/core.jar:lib/controlP5/library/*:lib/processing-opengl/library/*:lib/video/library/*" -d bin src/tom/videoGlitcher/VideoGlitcher.java src/tom/videoGlitcher/VideoGlitcherLogic.java src/tom/videoGlitcher/FfmpegVideoExporter.java

In VS Code, run the default build task:

• Terminal -> Run Build Task...
• Choose Build video_glitcher

Test

Current automated coverage targets the pure Java logic that was extracted from the fullscreen Processing sketch. It covers export filename generation, video-fit calculations, range normalization, glitch state transitions, and ffmpeg export setup.

Run the logic tests from the project root with:

mkdir -p test-bin && javac -d test-bin src/tom/videoGlitcher/VideoGlitcherLogic.java src/tom/videoGlitcher/FfmpegVideoExporter.java test/tom/videoGlitcher/VideoGlitcherLogicTest.java && java -cp test-bin tom.videoGlitcher.VideoGlitcherLogicTest

In VS Code, you can also run:

• Terminal -> Run Task...
• Choose Test video_glitcher logic

Smoke validation

The app also supports a non-interactive smoke mode for local runtime validation on macOS. Smoke mode runs in a normal window instead of Processing present mode and exits on its own.

Available tasks:

• Smoke Test video_glitcher Startup (macOS Apple Silicon)
• Smoke Test video_glitcher Load (macOS Apple Silicon)
• Smoke Test video_glitcher Export (macOS Apple Silicon)
• Smoke Test video_glitcher Process (macOS Apple Silicon)

The load, export, and process smoke tasks generate a short sample clip with ffmpeg and launch the app with --smoke-test. The load task validates the video pipeline without requiring interaction. The export task exercises the live interactive ffmpeg-backed export path. The process task runs the full-clip end-to-end mode and exits non-zero if the automatic export does not finish cleanly. The shipped command uses a longer smoke timeout because a heavy preset can render slower than realtime.

The smoke commands also accept the new retro presets, including --preset=vhs-decay and --preset=old-digicam, so you can validate the analogue-style control paths without touching the GUI.

You can also invoke smoke mode directly from the terminal:

java -cp "bin:lib/core.jar:lib/controlP5/library/*:lib/processing-opengl/library/*:lib/video/library/*" \
  -Dgstreamer.library.path="$PWD/lib/video/library/macos-aarch64" \
  -Dgstreamer.plugin.path="$PWD/lib/video/library/macos-aarch64/gstreamer-1.0" \
  tom.videoGlitcher.VideoGlitcher --smoke-test --smoke-frames=45

To auto-load a file and exercise live export:

java -cp "bin:lib/core.jar:lib/controlP5/library/*:lib/processing-opengl/library/*:lib/video/library/*" \
  -Dgstreamer.library.path="$PWD/lib/video/library/macos-aarch64" \
  -Dgstreamer.plugin.path="$PWD/lib/video/library/macos-aarch64/gstreamer-1.0" \
  tom.videoGlitcher.VideoGlitcher --smoke-test --video=/absolute/path/to/sample.mp4 --auto-export --smoke-frames=180 --export-frames=48

To auto-load a file and exercise full-process export:

java -cp "bin:lib/core.jar:lib/controlP5/library/*:lib/processing-opengl/library/*:lib/video/library/*" \
  -Dgstreamer.library.path="$PWD/lib/video/library/macos-aarch64" \
  -Dgstreamer.plugin.path="$PWD/lib/video/library/macos-aarch64/gstreamer-1.0" \
  tom.videoGlitcher.VideoGlitcher --smoke-test --video=/absolute/path/to/sample.mp4 --preset=Extreme --auto-process --smoke-frames=360

The rest of the app still requires manual validation because runtime behavior depends on a fullscreen PApplet, native video libraries, and live GUI interaction.

Run In VS Code

Task-based run

Use:

• Terminal -> Run Task...
• Choose Run video_glitcher (macOS Apple Silicon)

This task builds the app first, then runs it with the correct bundled GStreamer paths.

Additional platform tasks:

• Build video_glitcher (Linux x64)
• Run video_glitcher (Linux x64)
• Build video_glitcher (Windows x64)
• Run video_glitcher (Windows x64)

Distribution package

Use:

• Terminal -> Run Task...
• Choose Package video_glitcher (macOS app)

This creates a distributable app bundle at dist/video_glitcher.app.

Release bundles

Use:

• Terminal -> Run Task...
• Choose one of:
• Package video_glitcher Release (macOS Apple Silicon)
• Package video_glitcher Release (Linux x64)
• Package video_glitcher Release (Windows x64)

These create release archives in dist/ for each platform, for example:

• dist/video_glitcher-macos-aarch64.zip
• dist/video_glitcher-linux-amd64.zip
• dist/video_glitcher-windows-amd64.zip

Each bundle contains the application jar, the required libraries, the platform-specific video natives, and the matching launcher script.

Debug launch

Use:

• Run and Debug
• Select one of:
• Run video_glitcher (macOS Apple Silicon)
• Run video_glitcher (macOS Intel)
• Run video_glitcher (Linux x64 bundled)
• Run video_glitcher (Windows x64)
• Press F5

Each debug launch is configured with the correct bundled libraries and native video paths for that platform.

Run From Terminal

java -cp "bin:lib/core.jar:lib/controlP5/library/*:lib/processing-opengl/library/*:lib/video/library/*" \
  -Dgstreamer.library.path="$PWD/lib/video/library/macos-aarch64" \
  -Dgstreamer.plugin.path="$PWD/lib/video/library/macos-aarch64/gstreamer-1.0" \
  tom.videoGlitcher.VideoGlitcher

Controls

• Click background: open the file picker when no video is loaded
• L: load a video
• Space: pause or play
• G: turn glitching on or off
• F: toggle freeze mode
• H: show or hide the HUD
• U: show or hide the GUI
• E: start or stop live interactive export
• P: open a save dialog, then process the full clip from start to finish with the current settings
• S: save a frame as PNG
• Up: increase glitch intensity
• Down: decrease glitch intensity

Retro Controls

• The preset controls now use a button grid that includes the original digital presets, VHS Decay, Old Digicam, and Random.
• The GUI includes a dedicated retro section with six toggles: Tracking Tear, Head Switch, Chroma Drift, Scanline Wobble, Vertical Smear, and Column Drift.
• The top-right Advanced toggle switches the whole control surface between compact and full.
• GUI: Compact keeps the panel short and only exposes the presets plus four high-level sliders: Digital Intensity, Glitch Activity, Analogue Intensity, and Damage Texture.
• GUI: Full stretches the panel vertically, reveals the advanced timing sliders, the full digital toggle bank, the per-effect retro sliders, and supports mouse-wheel scrolling inside the panel.
• Full-process export snapshots the active retro settings the same way it snapshots the rest of the glitch configuration, so preview and export stay aligned.

Interface Notes

• Clicking inside the GUI does not trigger the background file picker.
• Glitching starts disabled before the first video is loaded so the empty-state text stays readable.
• After the first successful video load, glitching turns on automatically and then follows the user's chosen on/off state.
• Export Start / Export Stop stay in the interactive lane: you can let the preview run, change settings on the fly, and manually finish the MP4.
• Process Full opens a save dialog, snapshots the current glitch settings, rewinds to frame 0, renders the entire clip once, and finishes the MP4 automatically at the playback end.
• The GUI is layout-aware: compact mode keeps the panel shorter for quick preset-driven use, while full mode exposes the deeper digital and analogue tuning controls.
• The full-height panel now stops at the HUD/status bar instead of running behind it, and the footer transport row uses clearer labels such as REWIND.
• When the full panel grows beyond the visible space, use the mouse wheel while the pointer is over the GUI to scroll the control list.
• If the fitted video does not fill the screen, black mattes are drawn around it so glitches stay confined to the visible video area.
• The app now calls PApplet.hideMenuBar() before entering Processing present mode so fullscreen explicitly covers the macOS menu bar.

Notes

• The app is written as plain Java, so Processing types that are auto-imported in .pde sketches must be imported explicitly in the Java source.
• Video playback depends on the bundled Processing video library and native GStreamer files matching your platform.
• MP4 export depends on ffmpeg being installed and available on your PATH.
• The macOS packaging task builds an .app image with the required jars and bundled Apple Silicon video natives.
• Pushing a release tag like v1.1.2 triggers the GitHub Actions workflow to build and publish downloadable release bundles for macOS, Linux, and Windows.
• The Publish Homebrew Tap workflow waits for the macOS Apple Silicon and Linux x86_64 release ZIPs, renders Formula/video_glitcher.rb, syncs it into krahd/homebrew-tap, and removes the previous hyphenated formula file when the HOMEBREW_TAP_TOKEN repository secret is configured.

Contributing

Pull requests are welcome.