I'm attempting to add video to a page using the HTML5 code suggested by Mark Pilgrim. I can upload the video files and can show the video on the page but haven't succeeded in joining the two ends together.
I created a new has-one relationship:
'mp4video' => 'File',
and set up the CMS fields to upload the files.

How do I get the file path in PHP? In the template I can use $mp4video.filename and it shows the correct data but any attempt to get info from $this->mp4video just generates an error message about trying to get the properties of a non-object.

I am currently doing this:
$mp4object = DataObject::get_by_id('File', $this->getField('mp4videoID'));
$mp4path = $mp4object->getField('Filename');

but it seems a roundabout route. Can someone help with what must be a very basic hole in my knowledge?

cheers
bruce

I knew it was simple. I just couldn't find an example.

many thanks.