I do not believe this is the Correct Answer!
For 55 minutes, that's not a bad time at all and that format will be ready to be put on a DVD. Any other format will require a new transcode, which will just have to be done before putting on a DVD.
A 1080p H264 is not what a DVD is authored from. At least..not without transcoding it.
DVDs are SD ...not 1080p HD