puppeteer-img http://www.example.com --path example.jpeg --type jpeg

puppeteer-img --help
  Usage: puppeteer-img [options]

  Options:
    -V, --version                           output the version number
    -t, --type [type]                       The file type to generate. Options are jpeg or png. Defaults to png.
    -p, --path [path]                       The file path to save the image to.
    -w, --width [width]                     The width of the browser viewport. Default is 800
    -h, --height [height]                   The height of the browser viewport. Default is 600
    -s, --scale-factor [scale-factor]       Sets the device pixel scale factor when setting the viewport.  Defaults to 1.
    -x, --x [x]                             X coordinate for capturing a clip of the browser window
    -y, --y [y]                             Y coordinate for capturing a clip of the browser window
    --clip-width [clip-width]               Width of image when capturing a clip of the browser window
    --clip-height [clip-height]             Height of image when capturing a clip of the browser window
    -h, --help                              output usage information