The other answer does not emphasize some important points.
the fundamental matrix $F$ is a generalization of the essential matrix $E$
the fundamental matrix does not assume the cameras to be calibrated (i.e. you don't know $M$ and $M'$, which are the homographies needed to project a 3d point onto the image plane of camera $C$ and $C'$, respectively)
Does SVD compression only work for floating point images?
It seems quite obvious that it works for arbitrary images. Whether you are satisfied with the amount of compression or not doesn't really change the fact that it works.
I think looking at the compression ratio is going to lead to misleading results. Suppose you take two images: $I_1$ uses 8-bit ...