Export

Click Export… in the toolbar to open the advanced export dialog.

Export Dialog Options

Video Codec

Option	ffmpeg encoder	Notes
H.264 (default)	libx264	Best compatibility; works in all players/platforms
H.265 / HEVC	libx265	~50% smaller files than H.264 at same quality; requires player support
VP9	libvpx-vp9	Open format; good for web (WebM container)
ProRes	prores_ks	High-quality mastering format; large files; use with MOV container
AV1	libaom-av1	Excellent compression; very slow to encode

Container

Option	Extension	Best with
MP4 (default)	.mp4	H.264, H.265, AV1
QuickTime	.mov	ProRes, H.264
WebM	.webm	VP9, AV1
Matroska	.mkv	Any codec

MP4 and MOV containers get -movflags +faststart for web streaming compatibility.

Output Resolution

Option	Pixels	Use case
Same as project	Project width × height	No downscale
4K UHD	3840 × 2160	Archive / large screen
1080p	1920 × 1080	Standard HD delivery
720p	1280 × 720	Web / streaming
480p	854 × 480	Small file / mobile

Clips are letterboxed/pillarboxed to fit the chosen resolution while preserving aspect ratio.

Quality (CRF)

The CRF (Constant Rate Factor) slider controls quality vs. file size:

• Lower = better quality, larger file
• Higher = lower quality, smaller file
• Typical values: 18 (visually lossless) → 28 (acceptable web quality)
• Default: 23 (good balance)
• Not used for ProRes (lossless-ish by nature).

Audio Codec

Option	Notes
AAC (default)	Lossy; excellent compatibility
Opus	Lossy; excellent quality at low bitrates; best in WebM/MKV
FLAC	Lossless; large files
PCM	Uncompressed; very large; use for mastering

Audio Bitrate

Applies to AAC and Opus. Ignored for FLAC and PCM.

• Default: 192 kbps (high quality)
• Acceptable web quality: 128 kbps
• High fidelity: 256–320 kbps

Export Progress

After choosing the output file, an export progress dialog shows:

• A progress bar (0%–100%) driven by ffmpeg’s out_time_us reporting.
• A status label showing the output path.
• A Close button (available once export completes or errors).

Speed-Changed Clips

Clips with a speed multiplier or reverse playback are exported correctly:

• Fast/Slow Motion: Video setpts=PTS/speed and chained atempo filters for audio.
• Reverse Playback: Video reverse and audio areverse filters applied per-clip.
  • Reverse playback can be combined with speed changes (e.g. reverse at 2× speed).
• The atempo filter is limited to 0.5×–2.0× per instance; multiple are chained for 0.25× or 4×.

Overlay Clipping

• Secondary-track overlays now include overflow clipping: if a clip’s position (via Transform Inspector) exceeds the frame boundary, the overflow edges are cropped before padding.
• This ensures the exported PIP positions and framing match the Program Monitor preview exactly.

Notes

• Export requires ffmpeg to be installed and on $PATH.
• All video tracks are processed in timeline order.
• Audio is mixed from all non-muted audio tracks plus embedded audio in video clips.
• Export runs in a background thread; the UI remains responsive.