Add DiscardAlphaTransform to drop 4th channel if exists

Austin Blanton
1 parent c9ff1cc0
Showing 1 changed file with 28 additions and 0 deletions
openbr/plugins/cvt.cpp
@@ -162,6 +162,34 @@ BR_REGISTER(Transform, EnsureChannelsTransform)
  
 /*!
  * \ingroup transforms
+ * \brief Drop the alpha channel (if exists).
+ * \author Austin Blanton \cite imaus10
+ */
+class DiscardAlphaTransform : public UntrainableTransform
+{
+    Q_OBJECT
+
+    void project(const Template &src, Template &dst) const
+    {
+        if (src.m().channels() > 4 || src.m().channels() == 2) {
+            dst.file.fte = true;
+            return;
+        }
+
+        dst = src;
+        if (src.m().channels() == 4) {
+            std::vector<Mat> mv;
+            split(src, mv);
+            mv.pop_back();
+            merge(mv, dst);
+        }
+    }
+};
+
+BR_REGISTER(Transform, DiscardAlphaTransform)
+
+/*!
+ * \ingroup transforms
  * \brief Normalized RG color space.
  * \author Josh Klontz \cite jklontz
  */