diff -urNp old/modules/imgcodecs/src/grfmt_pxm.cpp new/modules/imgcodecs/src/grfmt_pxm.cpp
--- old/modules/imgcodecs/src/grfmt_pxm.cpp	2018-04-10 12:40:15.926177118 +0200
+++ new/modules/imgcodecs/src/grfmt_pxm.cpp	2018-04-10 12:42:39.932022243 +0200
@@ -309,7 +309,7 @@ bool  PxMDecoder::readData( Mat& img )
                         }
                     }
                     else
-                        memcpy( data, src, CV_ELEM_SIZE1(m_type)*m_width);
+                        memcpy( data, src, img.elemSize1()*m_width);
                 }
                 else
                 {