By default all images will be converted to JPG, simply use this code sample to convert your images to jpg:
In order to convert to png you just need to set the property to to png.
In order to convert to png you just need to set the property to to gif.
In order to convert to png you just need to set the property to to gif_animation.
Also, with this option can be configured the animation time and its loop with the properties gif_time and gif_loop