v0.30.0

The release about the picture and the sound of a clip: speed ramps, video stabilization, blend modes and noise reduction, plus tags for the media library.

Compatibility

Project files move to a newer schema. A project saved by 0.30 is refused by 0.29 (as 0.29 refuses any newer file), and every file is backed up before it is upgraded. Projects that use none of the new features export exactly as before.

Highlights

Speed ramps. A clip's speed can now change over its length: slow motion that eases in and out, a speed-up, a freeze-and-go. Draw it as a speed-over-time graph in the inspector, with up to 16 keys, linear or hold, and presets. Trims, splits, ripple, slip/roll/slide and linked audio keep the ramp, and the sound follows the picture.

Video stabilization. Steady a shaky clip from the inspector, with a strength and an automatic or fixed zoom. Kerf analyses the motion in the background and uses vid.stab when your FFmpeg has it, deshake otherwise. Until the analysis is done the clip plays and exports as shot, and the export dialog says so.

Blend modes. A clip can composite onto the tracks below with multiply, screen, overlay, hard light, add, darken, lighten, difference or exclusion. Opacity, masks, chroma key and fades still apply, and a multiplied clip fades out without flashing to black.

Noise reduction. A Denoise audio effect (FFmpeg's afftdn) with a reduction, a noise floor and optional noise tracking. Kerf takes out the delay it adds, so a denoised clip stays in sync and keeps its length. It is in the audio presets.

Asset tags. Tag media with plain (jump) or keyed (location: Cumbuco) tags. Select several assets in the bin (Ctrl/Cmd, Shift) to tag them at once, filter the bin by tag, and edit tags in the inspector. Kerf asks for tags after an import; turn that off under Settings › Editing.

Agents. 189 → 196 tools; nothing removed or renamed.

• set_speed_ramp, stabilize_clip and stabilization_status, set_blend_mode.
• edit_asset_tags, list_tags, and a tags filter on list_assets.
• assemble_by_tag builds a cut grouped by a tag, with a lower third or a title card for each group.
• set_audio_effects takes denoise, and the podcast_cleanup prompt now runs highpass → denoise → compressor → gate.
• review_cut flags a stabilized clip whose analysis hasn't landed.

Install

• macOS: .dmg (Apple Silicon or Intel). Needs FFmpeg: brew install ffmpeg.
• Windows: -setup.exe. FFmpeg is bundled, nothing else to install.
• Linux: .AppImage, .deb or .rpm, for x86_64 and arm64. Needs system FFmpeg. Pick the AppImage if you want in-place auto-updates; .deb / .rpm installs update through your package manager instead.