Adds flip function. Closes #36.

Author: sjmgarnier

NAMESPACE

@@ -77,6 +77,7 @@ export(findNonZero)
 export(findTransformECC)
 export(findTransformORB)
 export(fitEllipse)
+export(flip)
 export(floodFill)
 export(fourcc)
 export(fps)

R/geometry.R

@@ -92,4 +92,48 @@ resize <- function(image, height = NULL, width = NULL, fx = NULL, fy = NULL, int
                    Lanczos = 4,
                    exact = 5,
                    stop("This is not a valid interpolation method.")))
+}
+
+
+#' @title Flip an \code{\link{Image}}
+#'
+#' @description \code{flip} returns a flipped version of an \code{\link{Image}}
+#'  around one or both of its axes.
+#'
+#' @param image An \code{\link{Image}} object.
+#'
+#' @param type An integer indicating the type of flipping to be performed. If
+#'  \code{type = 0} (the default), the image is flipped around its x-axis; if
+#'  \code{type = 1} (or any positive value, then it is flipped around its y-axis;
+#'  finally, if \code{type = -1} (or any negative value, then it is flipped
+#'  around both axes.)
+#'
+#' @param in_place A logical indicating whether the change should be applied to
+#'  the image itself (TRUE, faster but destructive) or to a copy of it (FALSE,
+#'  the default, slower but non destructive).
+#'
+#' @return An \code{\link{Image}} object if \code{in_place=FALSE}. Otherwise, it
+#'  returns nothing and modifies \code{image} in place.
+#'
+#' @author Simon Garnier, \email{garnier@@njit.edu}
+#'
+#' @seealso \code{\link{Image}}
+#'
+#' @examples
+#' balloon <- image(system.file("sample_img/balloon1.png", package = "Rvision"))
+#' balloon_flipped <- flip(balloon, -1)
+#' plot(balloon_flipped)
+#'
+#' @export
+flip <- function(image, type = 0, in_place = FALSE) {
+  if (!isImage(image))
+    stop("This is not an Image object.")
+
+  if (in_place == TRUE) {
+    `_flip`(image, type)
+  } else {
+    out <- `_cloneImage`(image)
+    `_flip`(out, type)
+    out
+  }
 }

docs/pkgdown.yml

@@ -5,7 +5,7 @@ articles:
   z1_install: z1_install.html
   z2_io: z2_io.html
   z3_basic: z3_basic.html
-last_built: 2021-02-05T17:53Z
+last_built: 2021-02-05T18:09Z
 urls:
   reference: https://swarm-lab.github.io/ROpenCVLite//reference
   article: https://swarm-lab.github.io/ROpenCVLite//articles

docs/reference/flip-1.png

@@ -159,6 +159,9 @@
   <url>
     <loc>https://swarm-lab.github.io/ROpenCVLite//reference/fitEllipse.html</loc>
   </url>
+  <url>
+    <loc>https://swarm-lab.github.io/ROpenCVLite//reference/flip.html</loc>
+  </url>
   <url>
     <loc>https://swarm-lab.github.io/ROpenCVLite//reference/floodFill.html</loc>
   </url>

docs/reference/flip.html

@@ -3,4 +3,8 @@ Image _resize(Image image, int height, int width, double fx, double fy, int inte
 
   cv::resize(image.image, out, cv::Size(width, height), fx, fy, interpolation);
   return Image(out);
+}
+
+void _flip(Image image, int flipCode) {
+  cv::flip(image.image, image.image, flipCode);
 }

docs/reference/index.html

@@ -82,7 +82,6 @@ Rcpp::List _connectedComponents(Image image, int connectivity) {
 }
 
 void _watershed(Image image, Image markers) {
-  cv::Mat out;
   cv::watershed(image.image, markers.image);
 }