Screenjs NPM | npm.io

screenjs

Very small, Very fast, cross-platform library, to create a screenshot screenjs supports Mac, Windows, and Linux(X11).

What is created for?

For one project, I needed to make screenshots very quickly, and save them in an array of numbers (intmap), also it was necessary to sometimes save screenshots to the PNG file ...

Installation:

For Windows:

MinGW or other GCC

For Mac OS X:

Xcode Command Line Tools

For Ubuntu:

sudo apt-get install gcc libc6-dev
sudo apt-get install libx11-dev
sudo apt-get install xorg-dev

After all this:

npm install screenjs --save or npm install -g screenjs --save (from global)

API:

Import:

const Screen = require('screenjs').Screen; // The object responsible for the screenshots
const Bitmap = require('screenjs').Bitmap; // Additional functionality, saving to file, or base64, etc.

Methods:

Screen.getSize();
// Will return { width: 1366, height: 768 };

Screen.Capture();
/* Will return
{ width: 1366,
  height: 768,
  byteWidth: 5464,
  bitsPerPixel: 32,
  bytesPerPixel: 4,
  image: <Buffer ... >,
  intmap: Uint32Array [...] };
*/

Screen.Capture(x, y, width, height);
// Screen.Capture(10, 15, 100, 100);
/* Will return
{ width: 100,
  height: 100,
  byteWidth: 400,
  bitsPerPixel: 32,
  bytesPerPixel: 4,
  image: <Buffer ... >,
  intmap: Uint32Array [...] };
*/

Screen.CaptureGetIntMap();
/* Will return
{ width: 1366,
  height: 768,
  byteWidth: 5464,
  bitsPerPixel: 32,
  bytesPerPixel: 4,
  intmap: Uint32Array [...] };
*/

Screen.CaptureGetIntMap(x, y, width, height);
// Screen.CaptureGetIntMap(10, 15, 100, 100);
/* Will return
{ width: 100,
  height: 100,
  byteWidth: 400,
  bitsPerPixel: 32,
  bytesPerPixel: 4,
  intmap: Uint32Array [...] };
*/

Screen.CaptureGetImage();
/* Will return
{ width: 1366,
  height: 768,
  byteWidth: 5464,
  bitsPerPixel: 32,
  bytesPerPixel: 4,
  image: <Buffer ... > };
*/

Screen.CaptureGetImage(x, y, width, height);
// Screen.CaptureGetImage(10, 15, 100, 100);
/* Will return
{ width: 100,
  height: 100,
  byteWidth: 400,
  bitsPerPixel: 32,
  bytesPerPixel: 4,
  image: <Buffer ... > };
*/

Bitmap(img);
// return js bitmap object

Bitmap.rgbaToInt(red, green, blue, alpha);
// return number

Bitmap.intToRGBA(num);
// return rgba object

Bitmap.getBuffer();
// return buffer PNG image

Bitmap.getBase64();
// return base64 string (data:image/png;base64,...etc.)

Bitmap.write(pathFile, callback);
// save from file Async

Bitmap.writeSync(pathFile);
// save from file Sync

Examples:

const Screen = require('screenjs').Screen;
const Bitmap = require('screenjs').Bitmap;

const pic = Screen.Capture(); // It will work very quickly
console.log(pic); // And this will work slowly
const image = Bitmap(pic); // It will work very quickly
console.log(image); // And this will work slowly

const Screen = require('screenjs').Screen;
const Bitmap = require('screenjs').Bitmap;

const pic = Screen.CaptureGetImage(); // It will work very quickly
const image = Bitmap(pic); // It will work very quickly
image.writeSync('test.png'); //And this will work very slowly

const Screen = require('screenjs').Screen;

const pic = Screen.CaptureGetIntMap(); // It will work very quickly
console.log(image.intmap.length); //It will work very quickly