CLI

For a walkthrough, see Pre-encoding with the CLI. This page is the reference.

Usage

Terminal

npx vidscroll encode <input> [output] [options]
npx vidscroll help

Argument	Default	Meaning
`<input>`	required	The video to prepare. Any format ffmpeg reads.
`[output]`	input name with `.scroll.mp4`	Where to write the result. Must differ from the input. An existing file is overwritten.
`–resolution <px>`	`720`	Short side of the output. Never enlarges.
`–gop <frames>`	`10`	Frames between keyframes. Rounded to a whole number.
`–crf <n>`	`22`	Quality, lower is better and bigger.
`–fps <n>`	source rate	Frame rate cap. Faster sources are reduced; slower ones keep their rate.
`-h`, `–help`		Show the help text.

All values must be positive numbers, written after a space (--crf 24, not --crf=24). Unknown options are ignored.

The command calls ffmpeg with these settings:

Setting	Value
Video codec	H.264 (`libx264`), preset `slow`, `yuv420p`
Keyframes	Exactly every `–gop` frames, scene-cut keyframes off
Quality	`–crf`
Size	Short side scaled to `–resolution` or less
Frame rate	Capped at `–fps` when given
Audio	Removed
Streaming	Metadata at the start of the file (`+faststart`)

When it finishes, it prints the output path, its size, the input’s size and the keyframe interval.

The first one that exists is used:

If none is found, the command stops with instructions.