Fix grammar in the ocv_smooth filter documentation.

Originally committed as revision 25131 to svn://svn.ffmpeg.org/ffmpeg/trunk

doc/filters.texi

@@ -119,11 +119,11 @@ Apply smooth transform using libopencv.
 To enable this filter install libopencv library and headers and
 configure FFmpeg with --enable-libopencv.
 
-It accepts the following parameters:
+The filter accepts the following parameters:
 @var{type}:@var{param1}:@var{param2}:@var{param3}:@var{param4}.
 
 @var{type} is the type of smooth filter to apply, and can be one of
-the following value: "blur", "blur_no_scale", "median", "gaussian",
+the following values: "blur", "blur_no_scale", "median", "gaussian",
 "bilateral". The default value is "gaussian".
 
 @var{param1}, @var{param2}, @var{param3}, and @var{param4} are
@@ -134,8 +134,8 @@ parameters whose meanings depend on smooth type. @var{param1} and
 The default value for @var{param1} is 3, the default value for the
 other parameters is 0.
 
-These parameters corresponds to the parameters assigned to the
-libopencv function @code{cvSmooth}. Refer the official libopencv
+These parameters correspond to the parameters assigned to the
+libopencv function @code{cvSmooth}. Refer to the official libopencv
 documentation for the exact meaning of the parameters:
 @url{http://opencv.willowgarage.com/documentation/c/image_filtering.html}