Exporting
Pressing Export opens a short dialog before anything runs. It tells you what this export is going to do, and asks where to run it.
What the dialog tells you
- Straight cut. The video is copied into the new file without re-encoding. Seconds, and no quality loss.
- Re-encode, with the reasons: crop, size or format, tilt, mirror, colour, patches, or a frame-accurate cut. The clip is decoded and encoded again, which takes about as long as the clip is. See frame-accurate cuts for why.
Two options sit in the dialog as well. Frame-accurate makes the cut land exactly on the frame you chose, at the cost of a re-encode. Remove audio drops the sound track and leaves the picture alone.
In your browser
The default. The file never leaves your computer: the same ffmpeg that runs on a server runs inside the page, on your own processor and memory.
- A straight cut is instant anywhere.
- A re-encode depends on the machine. A laptop does roughly real time; a phone is slower.
- The clip and the result both have to fit in the browser's memory. Above about 1 GB an export may fail for lack of memory.
On our server
The clip is uploaded, cut by native ffmpeg on our server, and downloaded back. Choose it when a re-encode would be slow on this device, or when the file is too big for the browser.
- The upload is the whole file, so a good connection matters more than a fast computer.
- The file is deleted from the server right after the download, or after two hours if the download never happens.
- The server runs two jobs at a time; a third waits in line.
Either way the export is built from the same list of instructions, so the file that comes back is the same.
Batch export
Export all runs every clip that is new or has changed since its last export. A clip still marked as exported is skipped, so pressing it twice does not produce the same files twice. Edit or reset a clip to put it back in the queue.
Export from here runs from the selected clip to the end of the list, which is how you pick up a stopped batch.
At once sets how many clips run side by side in the browser. Two or three suits most laptops; more mostly competes for the same processor.
Stop ends the batch after the clips already running finish, and the status line names the first clip left, so you know where to continue.
Questions
Where does the file go?
To your downloads folder, under the output name shown in the clip panel. Rename it there before exporting if you want a different name.
Why is the exported file bigger or smaller than the original?
A straight cut is the same data, shorter. A re-encode is new data at a high quality setting, which can come out either larger or smaller than the source depending on how the original was encoded.