diff --git a/config.sh b/config.sh
index 1981e60b..ca089dad 100644
--- a/config.sh
+++ b/config.sh
@@ -40,7 +40,6 @@ function pre_build {
     echo '-----------------'
   else
     echo "Running for linux"
-    export LDFLAGS="-Wl,--no-as-needed -Wl,--no-undefined ${LDFLAGS}"
   fi
   qmake -query
 }
diff --git a/docker/Dockerfile_i686 b/docker/Dockerfile_i686
index 49c2d32c..c39331d0 100644
--- a/docker/Dockerfile_i686
+++ b/docker/Dockerfile_i686
@@ -1,10 +1,10 @@
 FROM quay.io/pypa/manylinux1_i686:latest
 
-RUN wget --no-check-certificate https://download.qt.io/official_releases/qt/4.8/4.8.7/qt-everywhere-opensource-src-4.8.7.tar.gz && \
+RUN curl -O -L https://download.qt.io/archive/qt/4.8/4.8.7/qt-everywhere-opensource-src-4.8.7.tar.gz && \
 	tar -xf qt-everywhere-opensource-src-4.8.7.tar.gz && \
 	cd qt-everywhere* && \
-	./configure -prefix /opt/Qt4.8.7 -release -opensource -confirm-license -qtnamespace Qt4 && \
-	gmake && \
+	./configure -prefix /opt/Qt4.8.7 -release -opensource -confirm-license && \
+	gmake -j5 && \
 	gmake install && \
 	cd .. && \
 	rm -rf qt-everywhere-opensource-src-4.8.7 && \
@@ -13,7 +13,7 @@ RUN wget --no-check-certificate https://download.qt.io/official_releases/qt/4.8/
 ENV QTDIR /opt/Qt4.8.7
 ENV PATH "$QTDIR/bin:$PATH"
 
-RUN wget --no-check-certificate https://cmake.org/files/v3.9/cmake-3.9.0.tar.gz && \
+RUN curl -O -L https://cmake.org/files/v3.9/cmake-3.9.0.tar.gz && \
 	tar -zxf cmake-3.9.0.tar.gz && \
 	cd cmake-3.9.0 && \
 	yum -y install curl-devel zlib-devel && \
diff --git a/docker/Dockerfile_x86_64 b/docker/Dockerfile_x86_64
index 51db79db..b855a73b 100644
--- a/docker/Dockerfile_x86_64
+++ b/docker/Dockerfile_x86_64
@@ -1,10 +1,10 @@
 FROM quay.io/pypa/manylinux1_x86_64:latest
 
-RUN wget --no-check-certificate https://download.qt.io/official_releases/qt/4.8/4.8.7/qt-everywhere-opensource-src-4.8.7.tar.gz && \
+RUN curl -O -L https://download.qt.io/archive/qt/4.8/4.8.7/qt-everywhere-opensource-src-4.8.7.tar.gz && \
 	tar -xf qt-everywhere-opensource-src-4.8.7.tar.gz && \
 	cd qt-everywhere* && \
-	./configure -prefix /opt/Qt4.8.7 -release -opensource -confirm-license -qtnamespace Qt4 && \
-	gmake && \
+	./configure -prefix /opt/Qt4.8.7 -release -opensource -confirm-license && \
+	gmake -j5 && \
 	gmake install && \
 	cd .. && \
 	rm -rf qt-everywhere-opensource-src-4.8.7 && \
@@ -13,7 +13,7 @@ RUN wget --no-check-certificate https://download.qt.io/official_releases/qt/4.8/
 ENV QTDIR /opt/Qt4.8.7
 ENV PATH "$QTDIR/bin:$PATH"
 
-RUN wget --no-check-certificate https://cmake.org/files/v3.9/cmake-3.9.0.tar.gz && \
+RUN curl -O -L https://cmake.org/files/v3.9/cmake-3.9.0.tar.gz && \
 	tar -zxf cmake-3.9.0.tar.gz && \
 	cd cmake-3.9.0 && \
 	yum -y install curl-devel zlib-devel && \
diff --git a/patches/patch1.patch b/patches/patch1.patch
deleted file mode 100644
index 63fc128d..00000000
--- a/patches/patch1.patch
+++ /dev/null
@@ -1,85 +0,0 @@
---- opencv/modules/highgui/src/window_QT.h	2018-06-28 13:13:55.119434000 +0300
-+++ opencv/modules/highgui/src/window_QT_patched.h	2018-06-30 17:35:55.145192900 +0300
-@@ -46,43 +46,51 @@
- #define QT_NO_DEBUG_OUTPUT
- #endif
- 
--#if defined( HAVE_QT_OPENGL )
--#include <QtOpenGL>
--#include <QGLWidget>
--#endif
--
--#include <QAbstractEventDispatcher>
- #include <QApplication>
--#include <QFile>
- #include <QPushButton>
--#include <QGraphicsView>
--#include <QSizePolicy>
--#include <QInputDialog>
--#include <QBoxLayout>
--#include <QSettings>
--#include <qtimer.h>
--#include <QtConcurrentRun>
--#include <QWaitCondition>
--#include <QKeyEvent>
--#include <QMetaObject>
- #include <QPointer>
--#include <QSlider>
--#include <QLabel>
--#include <QIODevice>
--#include <QShortcut>
--#include <QStatusBar>
--#include <QVarLengthArray>
--#include <QFileInfo>
--#include <QDate>
--#include <QFileDialog>
--#include <QToolBar>
--
--#include <QAction>
- #include <QCheckBox>
-+#include <QSlider>
- #include <QRadioButton>
--#include <QButtonGroup>
--#include <QMenu>
-+#include <QWidget>
-+#include <QGraphicsView>
- #include <QTest>
-+#include <QVarLengthArray>
-+#include <QHBoxLayout>
-+
-+#if defined( HAVE_QT_OPENGL )
-+#include <QtOpenGL>
-+#include <QGLWidget>
-+#endif
-+
-+QT_BEGIN_NAMESPACE
-+
-+class QAbstractEventDispatcher;
-+class QFile;
-+class QSizePolicy;
-+class QInputDialog;
-+class QBoxLayout;
-+class QSettings;
-+class QTimer;
-+class QtConcurrentRun;
-+class QWaitCondition;
-+class QKeyEvent;
-+class QMetaObject;
-+class QLabel;
-+class QIODevice;
-+class QShortcut;
-+class QStatusBar;
-+class QFileInfo;
-+class QDate;
-+class QFileDialog;
-+class QToolBar;
-+class QHBoxLayout;
-+
-+class QAction;
-+class QButtonGroup;
-+class QMenu;
-+
-+QT_END_NAMESPACE
- 
- //start private enum
- enum { CV_MODE_NORMAL = 0, CV_MODE_OPENGL = 1 };
diff --git a/patches/patch2.patch b/patches/patch2.patch
deleted file mode 100644
index 8ca8fbb3..00000000
--- a/patches/patch2.patch
+++ /dev/null
@@ -1,41 +0,0 @@
---- opencv/modules/highgui/src/window_QT.cpp	2018-06-30 01:04:51.649121800 +0300
-+++ opencv/modules/highgui/src/window_QT_patched.cpp	2018-06-30 17:09:28.697256300 +0300
-@@ -46,6 +46,30 @@
- 
- #include <window_QT.h>
- 
-+#include <QAbstractEventDispatcher>
-+#include <QFile>
-+#include <QSizePolicy>
-+#include <QInputDialog>
-+#include <QBoxLayout>
-+#include <QSettings>
-+#include <QTimer>
-+#include <QtConcurrentRun>
-+#include <QWaitCondition>
-+#include <QKeyEvent>
-+#include <QMetaObject>
-+#include <QLabel>
-+#include <QIODevice>
-+#include <QShortcut>
-+#include <QStatusBar>
-+#include <QFileInfo>
-+#include <QDate>
-+#include <QFileDialog>
-+#include <QToolBar>
-+
-+#include <QAction>
-+#include <QButtonGroup>
-+#include <QMenu>
-+
- #include <math.h>
- 
- #ifdef _WIN32
-@@ -60,7 +84,6 @@
-     #endif
- #endif
- 
--
- //Static and global first
- static GuiReceiver *guiMainThread = NULL;
- static int parameterSystemC = 1;
diff --git a/setup.py b/setup.py
index d7385ff1..6874e290 100644
--- a/setup.py
+++ b/setup.py
@@ -109,9 +109,6 @@ def main():
     # OS-specific components
     if (sys.platform == 'darwin' or sys.platform.startswith('linux')) and not build_headless:
         cmake_args.append("-DWITH_QT=4")
-        # Apply Qt namespace patches to OpenCV GUI code
-        subprocess.check_call("patch -p0 < patches/patch1.patch", shell=True)
-        subprocess.check_call("patch -p0 < patches/patch2.patch", shell=True)
 
     if build_headless:
         # it seems that cocoa cannot be disabled so on macOS the package is not truly headless