performs a simple/quick $2D$ spatial gradient measurement on the
video (usually a grayscale image). It highlights regions of high
spatial frequency which most ikely correspond to edges.
-\item [F\_rotate]~\\Rotates the input image.
+\item [F\_rotate]~\\Rotates the input image by an arbitrary angle expressed in radians. If you want to rotate
+by degrees, you can use the \textit{rotate} plugin instead.
\item [F\_sab]~\\Applies shape adaptive blur.
\item [F\_scale]~\\Scale the input video size and/or convert
the image format.