src/Intervention/Gif/Encoder.php
public function setCanvas($width, $height)
    {
        $this->canvasWidth = $width;
        $this->canvasHeight = $height;

        return $this;
    }
public function setCanvas($width, $height)
    {
        $this->canvasWidth = $width;
        $this->canvasHeight = $height;

        return $this;
    }
Set canvas dimensions

@param  int $width
@param  int $height
@return \Intervention\Image\Gd\Gif\Encoder