aperture-node

Record the screen on macOS from Node.js

Install

$ npm install aperture

Requires macOS 10.13 or later.

Usage

const delay = require('delay');
const aperture = require('aperture')();

const options = {
  fps: 30,
  cropArea: {
    x: 100,
    y: 100,
    width: 500,
    height: 500
  }
};

(async () => {
  await aperture.startRecording(options);
  await delay(3000);
  console.log(await aperture.stopRecording());
  //=> '/private/var/folders/3x/jf5977fn79jbglr7rk0tq4d00000gn/T/cdf4f7df426c97880f8c10a1600879f7.mp4'
})();

See example.js if you want to quickly try it out. (The example requires Node.js 8+)

API

aperture.screens() -> Promise<Object[]>

Get a list of screens. The first screen is the primary screen.

Example:

[{
  id: 69732482,
  name: 'Color LCD'
}]

aperture.audioDevices() -> Promise<Object[]>

Get a list of audio devices.

Example:

[{
  id: 'AppleHDAEngineInput:1B,0,1,0:1',
  name: 'Built-in Microphone'
}]

aperture.videoCodecs -> Map

Get a list of available video codecs. The key is the videoCodec option name and the value is the codec name. It only returns hevc if your computer supports HEVC hardware encoding.

Example:

Map {
  'h264' => 'H264',
  'hevc' => 'HEVC',
  'proRes422' => 'Apple ProRes 422',
  'proRes4444' => 'Apple ProRes 4444'
}

recorder = aperture()

recorder.startRecording(options?)

Returns a Promise that fullfills when the recording starts or rejects if the recording didn't start after 5 seconds.

recorder.isFileReady

Promise that fullfills with the path to the screen recording file when it's ready. This will never reject.

Only available while a recording is happening, undefined otherwise.

Usually, this resolves around 1 second before the recording starts, but that's not guaranteed.

recorder.pause()

Pauses the recording. To resume, call recorder.resume().

Returns a Promise that fullfills when the recording has been paused.

recorder.resume()

Resumes the recording if it's been paused.

Returns a Promise that fullfills when the recording has been resumed.

recorder.isPaused()

Returns a Promise that resolves with a boolean indicating whether or not the recording is currently paused.

recorder.stopRecording()

Returns a Promise for the path to the screen recording file.

Options

Type: object

fps

Type: number
Default: 30

Number of frames per seconds.

cropArea

Type: object
Default: undefined

Record only an area of the screen. Accepts an object with x, y, width, height properties.

showCursor

Type: boolean
Default: true

Show the cursor in the screen recording.

highlightClicks

Type: boolean
Default: false

Highlight cursor clicks in the screen recording.

Enabling this will also enable the showCursor option.

screenId

Type: number
Default: aperture.screens()[0] (Primary screen)

Screen to record.

audioDeviceId

Type: string
Default: undefined

Audio device to include in the screen recording. Should be one of the id's from aperture.audioDevices().

videoCodec

Type: string
Default: 'h264'
Values: 'hevc' | 'h264' | 'proRes422' | 'proRes4444'

A computer with Intel 6th generation processor or newer is strongly recommended for the hevc codec, as otherwise it will use software encoding, which only produces 3 FPS fullscreen recording.

The proRes422 and proRes4444 codecs are uncompressed data. They will create huge files.

Why

Aperture was built to fulfill the needs of Kap, providing a JavaScript interface to the best available method for recording the screen. That's why it's currently a wrapper for a Swift script that records the screen using the AVFoundation framework.

But you can use ffmpeg -f avfoundation...

Yes, we can, but the performance is terrible:

Recording the entire screen with ffmpeg -f avfoundation -i 1 -y test.mp4:

Recording the entire screen with Aperture:

Related

• Aperture - The Swift framework used in this package