Mediaelement and frames

I would like to interface with the MediaElement using frames and not
TimeSpan. I need these frames to be exact, just like any graphic tool that
knows that frame number 125 (for example) is exactly frame 125 and not an
approximation translated from milliseconds.

There are two approaches that may be of help:
1. How can I find out the frame rate of a video (not playback rate, the
frame rate of the original video file, which any graphic tool can understand).
2. How can I find out the total number of frames in the video.