PHP-FFMpeg filters() - > resize()throw使用未定义的常量RESIZEMODE_INSET

I'm using PHP-FFMpeg to use FFMpeg with php, unfortunately I can't set resize filter.

This is my code:

$video = $ffmpeg->open('video.mov');

$dimension = new FFMpeg\Coordinate\Dimension(1920, 1080);
$video->filters()
      ->resize($dimension, RESIZEMODE_INSET, true, 1)
      ->synchronize();

$format = new FFMpeg\Format\Video\X264('aac', 'libx264');
$format->setAudioChannels(2)->setAudioKiloBitrate(256);
$video->save($format, 'video.mp4');

But it throws this error:

Use of undefined constant RESIZEMODE_INSET - assumed 'RESIZEMODE_INSET'

I tried also:

->resize($dimension, 'RESIZEMODE_INSET', true, 1)

and

->resize($dimension, 'inset', true, 1)

But I can't get the video converted without stretching.

Thanks in advance