Shadow Convert

Convert video, audio, and images locally on Linux.

Drop a file, pick an action, convert. Shadow Convert is a native GTK4 / libadwaita desktop app. It is not a website, not a localhost server, and not Electron.

What it does

• Video — MP4, MKV, WebM; 1080p / 1440p / 4K (never silent-upscale); compress; extract audio; remove audio; trim; GIF
• Audio — MP3, WAV, FLAC, AAC, Opus; normalize loudness; trim
• Images — PNG, JPEG, WebP, AVIF; resize without upscaling; compress
• Probes the file with ffprobe and inspects content, not just the extension
• Quality presets: Small, Balanced, High (default), Maximum
• Hardware encoding (NVENC H.264 / HEVC / AV1) when FFmpeg exposes it and the job is long enough to benefit; CPU fallback is always available
• Stream-copy / remux when the codecs already fit the target container
• Progress with ETA when FFmpeg reports time; Cancel stops child processes
• Originals are never overwritten
• Offline. No accounts, ads, telemetry, or cloud

Screenshots

Screenshots belong in docs/screenshots/ and must not include private filenames or home-directory paths. If this folder is empty, the app still builds and runs; capture them locally after install if you want gallery images.

Install (user, no root)

git clone https://github.com/Shadowfetchapps/Shadow-Convert.git
cd Shadow-Convert
cargo build --release
./scripts/install-user.sh

This copies the binary to ~/.local/bin/shadow-convert, the desktop file to ~/.local/share/applications/, and icons to ~/.local/share/icons/hicolor/.

Launch from the app menu or:

shadow-convert

A .deb is produced with ./scripts/build-deb.sh (see BUILDING.md). System-wide dpkg -i needs administrator rights; the user install does not.

Requirements

• Linux desktop with GTK 4 and libadwaita
• FFmpeg / ffprobe (video and audio)
• ImageMagick convert (preferred for images; FFmpeg is the fallback)

Optional: an FFmpeg build with NVENC, libwebp, libaom-av1, libmp3lame, libopus.

Limitations (honest)

• AVIF depends on ImageMagick AVIF support or FFmpeg libaom-av1
• ICC color profiles are preserved when ImageMagick can do so; some FFmpeg still-image paths flatten toward a typical display encoding
• Size estimates are approximate
• Multi-file drops open the first file; use Shadow Batch Processor for bulk jobs
• GIF conversion re-encodes and can be slow on long clips
• Hardware encode is detected at runtime. It is never assumed from a particular GPU

License

MIT. See LICENSE.