From 9fc0cabdf556aafae928c51fbc0390e3071be958 Mon Sep 17 00:00:00 2001
From: catree <catree.catreus@outlook.com>
Date: Thu, 17 May 2018 14:19:08 +0200
Subject: [PATCH] Add Java and Python code for trackbar tutorial.
---
.../highgui/table_of_content_highgui.markdown | 2 +
.../highgui/trackbar/trackbar.markdown | 88 ++++++++++---
.../HighGUI/AddingImagesTrackbar.cpp | 10 +-
.../erosion_dilatation/MorphologyDemo1.java | 8 +-
.../opening_closing_hats/MorphologyDemo2.java | 8 +-
.../trackbar/AddingImagesTrackbar.java | 119 ++++++++++++++++++
.../highgui/trackbar/AddingImagesTrackbar.py | 48 +++++++
7 files changed, 258 insertions(+), 25 deletions(-)
create mode 100644 samples/java/tutorial_code/highgui/trackbar/AddingImagesTrackbar.java
create mode 100644 samples/python/tutorial_code/highgui/trackbar/AddingImagesTrackbar.py
diff --git a/doc/tutorials/highgui/table_of_content_highgui.markdown b/doc/tutorials/highgui/table_of_content_highgui.markdown
index a8f1d4e344..fb5a343664 100644
--- a/doc/tutorials/highgui/table_of_content_highgui.markdown
+++ b/doc/tutorials/highgui/table_of_content_highgui.markdown
@@ -5,6 +5,8 @@ This section contains tutorials about how to use the built-in graphical user int
- @subpage tutorial_trackbar
+ *Languages:* C++, Java, Python
+
*Compatibility:* \> OpenCV 2.0
*Author:* Ana Huamán
diff --git a/doc/tutorials/highgui/trackbar/trackbar.markdown b/doc/tutorials/highgui/trackbar/trackbar.markdown
index 13898712ab..d6700d6387 100644
--- a/doc/tutorials/highgui/trackbar/trackbar.markdown
+++ b/doc/tutorials/highgui/trackbar/trackbar.markdown
@@ -1,11 +1,11 @@
Adding a Trackbar to our applications! {#tutorial_trackbar}
======================================
-- In the previous tutorials (about *linear blending* and the *brightness and contrast
- adjustments*) you might have noted that we needed to give some **input** to our programs, such
- as \f$\alpha\f$ and \f$beta\f$. We accomplished that by entering this data using the Terminal
-- Well, it is time to use some fancy GUI tools. OpenCV provides some GUI utilities (*highgui.hpp*)
- for you. An example of this is a **Trackbar**
+- In the previous tutorials (about @ref tutorial_adding_images and the @ref tutorial_basic_linear_transform)
+ you might have noted that we needed to give some **input** to our programs, such
+ as \f$\alpha\f$ and \f$beta\f$. We accomplished that by entering this data using the Terminal.
+- Well, it is time to use some fancy GUI tools. OpenCV provides some GUI utilities (**highgui** module)
+ for you. An example of this is a **Trackbar**.
@@ -24,26 +24,73 @@ Code
Let's modify the program made in the tutorial @ref tutorial_adding_images. We will let the user enter the
\f$\alpha\f$ value by using the Trackbar.
+
+@add_toggle_cpp
This tutorial code's is shown lines below. You can also download it from
[here](https://github.com/opencv/opencv/tree/master/samples/cpp/tutorial_code/HighGUI/AddingImagesTrackbar.cpp)
@include cpp/tutorial_code/HighGUI/AddingImagesTrackbar.cpp
+@end_toggle
+
+@add_toggle_java
+This tutorial code's is shown lines below. You can also download it from
+[here](https://github.com/opencv/opencv/tree/master/samples/java/tutorial_code/highgui/trackbar/AddingImagesTrackbar.java)
+@include java/tutorial_code/highgui/trackbar/AddingImagesTrackbar.java
+@end_toggle
+
+@add_toggle_python
+This tutorial code's is shown lines below. You can also download it from
+[here](https://github.com/opencv/opencv/tree/master/samples/python/tutorial_code/highgui/trackbar/AddingImagesTrackbar.py)
+@include python/tutorial_code/highgui/trackbar/AddingImagesTrackbar.py
+@end_toggle
Explanation
-----------
We only analyze the code that is related to Trackbar:
--# First, we load two images, which are going to be blended.
- @snippet cpp/tutorial_code/HighGUI/AddingImagesTrackbar.cpp load
+- First, we load two images, which are going to be blended.
+
+@add_toggle_cpp
+@snippet cpp/tutorial_code/HighGUI/AddingImagesTrackbar.cpp load
+@end_toggle
+
+@add_toggle_java
+@snippet java/tutorial_code/highgui/trackbar/AddingImagesTrackbar.java load
+@end_toggle
+
+@add_toggle_python
+@snippet python/tutorial_code/highgui/trackbar/AddingImagesTrackbar.py load
+@end_toggle
--# To create a trackbar, first we have to create the window in which it is going to be located. So:
- @snippet cpp/tutorial_code/HighGUI/AddingImagesTrackbar.cpp window
+- To create a trackbar, first we have to create the window in which it is going to be located. So:
--# Now we can create the Trackbar:
- @snippet cpp/tutorial_code/HighGUI/AddingImagesTrackbar.cpp create_trackbar
+@add_toggle_cpp
+@snippet cpp/tutorial_code/HighGUI/AddingImagesTrackbar.cpp window
+@end_toggle
- Note the following:
+@add_toggle_java
+@snippet java/tutorial_code/highgui/trackbar/AddingImagesTrackbar.java window
+@end_toggle
+@add_toggle_python
+@snippet python/tutorial_code/highgui/trackbar/AddingImagesTrackbar.py window
+@end_toggle
+
+- Now we can create the Trackbar:
+
+@add_toggle_cpp
+@snippet cpp/tutorial_code/HighGUI/AddingImagesTrackbar.cpp create_trackbar
+@end_toggle
+
+@add_toggle_java
+@snippet java/tutorial_code/highgui/trackbar/AddingImagesTrackbar.java create_trackbar
+@end_toggle
+
+@add_toggle_python
+@snippet python/tutorial_code/highgui/trackbar/AddingImagesTrackbar.py create_trackbar
+@end_toggle
+
+Note the following (C++ code):
- Our Trackbar has a label **TrackbarName**
- The Trackbar is located in the window named **Linear Blend**
- The Trackbar values will be in the range from \f$0\f$ to **alpha_slider_max** (the minimum
@@ -51,10 +98,21 @@ We only analyze the code that is related to Trackbar:
- The numerical value of Trackbar is stored in **alpha_slider**
- Whenever the user moves the Trackbar, the callback function **on_trackbar** is called
--# Finally, we have to define the callback function **on_trackbar**
- @snippet cpp/tutorial_code/HighGUI/AddingImagesTrackbar.cpp on_trackbar
+Finally, we have to define the callback function **on_trackbar** for C++ and Python code, using an anonymous inner class listener in Java
+
+@add_toggle_cpp
+@snippet cpp/tutorial_code/HighGUI/AddingImagesTrackbar.cpp on_trackbar
+@end_toggle
+
+@add_toggle_java
+@snippet java/tutorial_code/highgui/trackbar/AddingImagesTrackbar.java on_trackbar
+@end_toggle
+
+@add_toggle_python
+@snippet python/tutorial_code/highgui/trackbar/AddingImagesTrackbar.py on_trackbar
+@end_toggle
- Note that:
+Note that (C++ code):
- We use the value of **alpha_slider** (integer) to get a double value for **alpha**.
- **alpha_slider** is updated each time the trackbar is displaced by the user.
- We define *src1*, *src2*, *dist*, *alpha*, *alpha_slider* and *beta* as global variables,
diff --git a/samples/cpp/tutorial_code/HighGUI/AddingImagesTrackbar.cpp b/samples/cpp/tutorial_code/HighGUI/AddingImagesTrackbar.cpp
index 51522fa5ca..dce34e7eb4 100644
--- a/samples/cpp/tutorial_code/HighGUI/AddingImagesTrackbar.cpp
+++ b/samples/cpp/tutorial_code/HighGUI/AddingImagesTrackbar.cpp
@@ -6,9 +6,10 @@
#include "opencv2/imgcodecs.hpp"
#include "opencv2/highgui.hpp"
-#include <stdio.h>
+#include <iostream>
using namespace cv;
+using std::cout;
/** Global Variables */
const int alpha_slider_max = 100;
@@ -29,11 +30,8 @@ Mat dst;
static void on_trackbar( int, void* )
{
alpha = (double) alpha_slider/alpha_slider_max ;
-
beta = ( 1.0 - alpha );
-
addWeighted( src1, alpha, src2, beta, 0.0, dst);
-
imshow( "Linear Blend", dst );
}
//![on_trackbar]
@@ -50,8 +48,8 @@ int main( void )
src2 = imread("../data/WindowsLogo.jpg");
//![load]
- if( src1.empty() ) { printf("Error loading src1 \n"); return -1; }
- if( src2.empty() ) { printf("Error loading src2 \n"); return -1; }
+ if( src1.empty() ) { cout << "Error loading src1 \n"; return -1; }
+ if( src2.empty() ) { cout << "Error loading src2 \n"; return -1; }
/// Initialize values
alpha_slider = 0;
diff --git a/samples/java/tutorial_code/ImgProc/erosion_dilatation/MorphologyDemo1.java b/samples/java/tutorial_code/ImgProc/erosion_dilatation/MorphologyDemo1.java
index 386f94a553..8a52884984 100644
--- a/samples/java/tutorial_code/ImgProc/erosion_dilatation/MorphologyDemo1.java
+++ b/samples/java/tutorial_code/ImgProc/erosion_dilatation/MorphologyDemo1.java
@@ -25,7 +25,7 @@ import org.opencv.imgproc.Imgproc;
public class MorphologyDemo1 {
private static final String[] ELEMENT_TYPE = { "Rectangle", "Cross", "Ellipse" };
private static final String[] MORPH_OP = { "Erosion", "Dilatation" };
- private static int maxKernelSize = 21;
+ private static final int MAX_KERNEL_SIZE = 21;
private Mat matImgSrc;
private Mat matImgDst = new Mat();
private int elementType = Imgproc.CV_SHAPE_RECT;
@@ -83,7 +83,11 @@ public class MorphologyDemo1 {
sliderPanel.add(elementTypeBox);
sliderPanel.add(new JLabel("Kernel size: 2n + 1"));
- JSlider slider = new JSlider(0, maxKernelSize, 0);
+ JSlider slider = new JSlider(0, MAX_KERNEL_SIZE, 0);
+ slider.setMajorTickSpacing(5);
+ slider.setMinorTickSpacing(5);
+ slider.setPaintTicks(true);
+ slider.setPaintLabels(true);
slider.addChangeListener(new ChangeListener() {
@Override
public void stateChanged(ChangeEvent e) {
diff --git a/samples/java/tutorial_code/ImgProc/opening_closing_hats/MorphologyDemo2.java b/samples/java/tutorial_code/ImgProc/opening_closing_hats/MorphologyDemo2.java
index e5d80280a9..07d2f6e44d 100644
--- a/samples/java/tutorial_code/ImgProc/opening_closing_hats/MorphologyDemo2.java
+++ b/samples/java/tutorial_code/ImgProc/opening_closing_hats/MorphologyDemo2.java
@@ -27,7 +27,7 @@ public class MorphologyDemo2 {
private static final int[] MORPH_OP_TYPE = { Imgproc.MORPH_OPEN, Imgproc.MORPH_CLOSE,
Imgproc.MORPH_GRADIENT, Imgproc.MORPH_TOPHAT, Imgproc.MORPH_BLACKHAT };
private static final String[] ELEMENT_TYPE = { "Rectangle", "Cross", "Ellipse" };
- private static int maxKernelSize = 21;
+ private static final int MAX_KERNEL_SIZE = 21;
private Mat matImgSrc;
private Mat matImgDst = new Mat();
private int morphOpType = Imgproc.MORPH_OPEN;
@@ -97,7 +97,11 @@ public class MorphologyDemo2 {
sliderPanel.add(elementTypeBox);
sliderPanel.add(new JLabel("Kernel size: 2n + 1"));
- JSlider slider = new JSlider(0, maxKernelSize, 0);
+ JSlider slider = new JSlider(0, MAX_KERNEL_SIZE, 0);
+ slider.setMajorTickSpacing(5);
+ slider.setMinorTickSpacing(5);
+ slider.setPaintTicks(true);
+ slider.setPaintLabels(true);
slider.addChangeListener(new ChangeListener() {
@Override
public void stateChanged(ChangeEvent e) {
diff --git a/samples/java/tutorial_code/highgui/trackbar/AddingImagesTrackbar.java b/samples/java/tutorial_code/highgui/trackbar/AddingImagesTrackbar.java
new file mode 100644
index 0000000000..5eda2198da
--- /dev/null
+++ b/samples/java/tutorial_code/highgui/trackbar/AddingImagesTrackbar.java
@@ -0,0 +1,119 @@
+import java.awt.BorderLayout;
+import java.awt.Container;
+import java.awt.Image;
+
+import javax.swing.BoxLayout;
+import javax.swing.ImageIcon;
+import javax.swing.JFrame;
+import javax.swing.JLabel;
+import javax.swing.JPanel;
+import javax.swing.JSlider;
+import javax.swing.event.ChangeEvent;
+import javax.swing.event.ChangeListener;
+
+import org.opencv.core.Core;
+import org.opencv.core.Mat;
+import org.opencv.highgui.HighGui;
+import org.opencv.imgcodecs.Imgcodecs;
+
+public class AddingImagesTrackbar {
+ private static final int ALPHA_SLIDER_MAX = 100;
+ private int alphaVal = 0;
+ private Mat matImgSrc1;
+ private Mat matImgSrc2;
+ private Mat matImgDst = new Mat();
+ private JFrame frame;
+ private JLabel imgLabel;
+
+ public AddingImagesTrackbar(String[] args) {
+ //! [load]
+ String imagePath1 = "../data/LinuxLogo.jpg";
+ String imagePath2 = "../data/WindowsLogo.jpg";
+ if (args.length > 1) {
+ imagePath1 = args[0];
+ imagePath2 = args[1];
+ }
+ matImgSrc1 = Imgcodecs.imread(imagePath1);
+ matImgSrc2 = Imgcodecs.imread(imagePath2);
+ //! [load]
+ if (matImgSrc1.empty()) {
+ System.out.println("Empty image: " + imagePath1);
+ System.exit(0);
+ }
+ if (matImgSrc2.empty()) {
+ System.out.println("Empty image: " + imagePath2);
+ System.exit(0);
+ }
+
+ //! [window]
+ // Create and set up the window.
+ frame = new JFrame("Linear Blend");
+ frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
+ // Set up the content pane.
+ Image img = HighGui.toBufferedImage(matImgSrc2);
+ addComponentsToPane(frame.getContentPane(), img);
+ // Use the content pane's default BorderLayout. No need for
+ // setLayout(new BorderLayout());
+ // Display the window.
+ frame.pack();
+ frame.setVisible(true);
+ //! [window]
+ }
+
+ private void addComponentsToPane(Container pane, Image img) {
+ if (!(pane.getLayout() instanceof BorderLayout)) {
+ pane.add(new JLabel("Container doesn't use BorderLayout!"));
+ return;
+ }
+
+ JPanel sliderPanel = new JPanel();
+ sliderPanel.setLayout(new BoxLayout(sliderPanel, BoxLayout.PAGE_AXIS));
+
+ //! [create_trackbar]
+ sliderPanel.add(new JLabel(String.format("Alpha x %d", ALPHA_SLIDER_MAX)));
+ JSlider slider = new JSlider(0, ALPHA_SLIDER_MAX, 0);
+ slider.setMajorTickSpacing(20);
+ slider.setMinorTickSpacing(5);
+ slider.setPaintTicks(true);
+ slider.setPaintLabels(true);
+ //! [create_trackbar]
+ //! [on_trackbar]
+ slider.addChangeListener(new ChangeListener() {
+ @Override
+ public void stateChanged(ChangeEvent e) {
+ JSlider source = (JSlider) e.getSource();
+ alphaVal = source.getValue();
+ update();
+ }
+ });
+ //! [on_trackbar]
+ sliderPanel.add(slider);
+
+ pane.add(sliderPanel, BorderLayout.PAGE_START);
+ imgLabel = new JLabel(new ImageIcon(img));
+ pane.add(imgLabel, BorderLayout.CENTER);
+ }
+
+ private void update() {
+ double alpha = alphaVal / (double) ALPHA_SLIDER_MAX;
+ double beta = 1.0 - alpha;
+ Core.addWeighted(matImgSrc1, alpha, matImgSrc2, beta, 0, matImgDst);
+ Image img = HighGui.toBufferedImage(matImgDst);
+ imgLabel.setIcon(new ImageIcon(img));
+ frame.repaint();
+ }
+
+ public static void main(String[] args) {
+ // Load the native OpenCV library
+ System.loadLibrary(Core.NATIVE_LIBRARY_NAME);
+
+ // Schedule a job for the event dispatch thread:
+ // creating and showing this application's GUI.
+ javax.swing.SwingUtilities.invokeLater(new Runnable() {
+ @Override
+ public void run() {
+ new AddingImagesTrackbar(args);
+ }
+ });
+ }
+}
diff --git a/samples/python/tutorial_code/highgui/trackbar/AddingImagesTrackbar.py b/samples/python/tutorial_code/highgui/trackbar/AddingImagesTrackbar.py
new file mode 100644
index 0000000000..2ccc978a8e
--- /dev/null
+++ b/samples/python/tutorial_code/highgui/trackbar/AddingImagesTrackbar.py
@@ -0,0 +1,48 @@
+from __future__ import print_function
+from __future__ import division
+import cv2 as cv
+import argparse
+
+alpha_slider_max = 100
+title_window = 'Linear Blend'
+
+## [on_trackbar]
+def on_trackbar(val):
+ alpha = val / alpha_slider_max
+ beta = ( 1.0 - alpha )
+ dst = cv.addWeighted(src1, alpha, src2, beta, 0.0)
+ cv.imshow(title_window, dst)
+## [on_trackbar]
+
+parser = argparse.ArgumentParser(description='Code for Adding a Trackbar to our applications tutorial.')
+parser.add_argument('--input1', help='Path to the first input image.', default='../data/LinuxLogo.jpg')
+parser.add_argument('--input2', help='Path to the second input image.', default='../data/WindowsLogo.jpg')
+args = parser.parse_args()
+
+## [load]
+# Read images ( both have to be of the same size and type )
+src1 = cv.imread(args.input1)
+src2 = cv.imread(args.input2)
+## [load]
+if src1 is None:
+ print('Could not open or find the image: ', args.input1)
+ exit(0)
+
+if src2 is None:
+ print('Could not open or find the image: ', args.input2)
+ exit(0)
+
+## [window]
+cv.namedWindow(title_window)
+## [window]
+
+## [create_trackbar]
+trackbar_name = 'Alpha x %d' % alpha_slider_max
+cv.createTrackbar(trackbar_name, title_window , 0, alpha_slider_max, on_trackbar)
+## [create_trackbar]
+
+# Show some stuff
+on_trackbar(0)
+
+# Wait until user press some key
+cv.waitKey()