(PECL imagick 2, PECL imagick 3)
Imagick::getImageBlob — Returns the image sequence as a blob
Implements direct to memory image formats. It returns the image sequence as a string. The format of the image determines the format of the returned blob (GIF, JPEG, PNG, etc.). To return a different image format, use Imagick::setImageFormat().
Returns a string containing the image.
错误时抛出 ImagickException。