How to get video duration from Graph API?

Are there any methods to query the duration of Facebook Video by Graph API?

There's no related field from document.

http://developers.facebook.com/docs/reference/api开发者_如何学Python/video/

If Graph API does not support now, will it support in the future and when? Great thanks for any inputs.

---

Now in 2015, Facebook provides the video duration with the "length" field:

• https://developers.facebook.com/docs/graph-api/reference/video

---

to get the video duration, get the video and then get the duration directly by "Decoding" or parsing the video file.