avfilter: add swaprect filter

Signed-off-by: Paul B Mahol <onemda@gmail.com>

1 files changed, 54 insertions, 0 deletions

diff --git a/doc/filters.texi b/doc/filters.texi
index 3751f82e38..6b57c0cd28 100644
--- a/doc/filters.texi
+++ b/doc/filters.texi
@@ -11473,6 +11473,60 @@ Interpolate) pixel art scaling algorithm.
 
 Useful for enlarging pixel art images without reducing sharpness.
 
+@section swaprect
+
+Swap two rectangular objects in video.
+
+This filter accepts the following options:
+
+@table @option
+@item w
+Set object width.
+
+@item h
+Set object height.
+
+@item x1
+Set 1st rect x coordinate.
+
+@item y1
+Set 1st rect y coordinate.
+
+@item x2
+Set 2nd rect x coordinate.
+
+@item y2
+Set 2nd rect y coordinate.
+
+All expressions are evaluated once for each frame.
+@end table
+
+The all options are expressions containing the following constants:
+
+@table @option
+@item w
+@item h
+The input width and height.
+
+@item a
+same as @var{w} / @var{h}
+
+@item sar
+input sample aspect ratio
+
+@item dar
+input display aspect ratio, it is the same as (@var{w} / @var{h}) * @var{sar}
+
+@item n
+The number of the input frame, starting from 0.
+
+@item t
+The timestamp expressed in seconds. It's NAN if the input timestamp is unknown.
+
+@item pos
+the position in the file of the input frame, NAN if unknown
+@end table
+
 @section swapuv
 Swap U & V plane.