Saturday, May 27, 2017

Using Python for .NET the clr python module - part 001 .

Python for .NET is available as a source release and as a Windows installer for various versions of Python and the common language runtime from the Python for .NET website .
Let's install it under Windows 10.
C:\Python27\Scripts>pip install pythonnet
Collecting pythonnet
  Downloading pythonnet-2.3.0-cp27-cp27m-win32.whl (58kB)
    100% |################################| 61kB 740kB/s
Installing collected packages: pythonnet
Successfully installed pythonnet-2.3.0
Now I will show you how to use form and buttons.
First you need to run the python code into python script files.
First example is simple:
import clr

clr.AddReference("System.Windows.Forms")

from System.Windows.Forms import Application, Form

class IForm(Form):

    def __init__(self):
        self.Text = 'Simple'
        self.Width = 640
        self.Height = 480
        self.CenterToScreen()

Application.Run(IForm())
The next example come with one button and tooltips for form and button:
import clr

clr.AddReference("System.Windows.Forms")
clr.AddReference("System.Drawing")

from System.Windows.Forms import Application, Form
from System.Windows.Forms import Button, ToolTip
from System.Drawing import Point, Size

class IForm(Form):

    def __init__(self):
        self.Text = 'Tooltips'
        self.CenterToScreen()
        self.Size = Size(640, 480)

        tooltip = ToolTip()
        tooltip.SetToolTip(self, "This is a Form")

        button = Button()
        button.Parent = self
        button.Text = "Button"
        button.Location = Point(50, 70)

        tooltip.SetToolTip(button, "This is a Button")


Application.Run(IForm())
This is the result of this python script.

Another example is how to see the interfaces that are part of a .NET assembly:
>>> import System.Collections
>>> interfaces = [entry for entry in dir(System.Collections)
... if entry.startswith('I')]
>>> for entry in interfaces:
...   print entry
...
ICollection
IComparer
IDictionary
IDictionaryEnumerator
IEnumerable
IEnumerator
IEqualityComparer
IHashCodeProvider
IList
IStructuralComparable
IStructuralEquatable

Friday, May 26, 2017

OpenGL and OpenCV with python 2.7 - part 005.

In this tutorial I will show you how to mount OpenCV in the Windows 10 operating system with any python version.
You can use the same steps for other versions of python.
Get the wheel binary package opencv_python-3.2.0.7-cp27-cp27m-win32.whl from here.
C:\Python27>

C:\Python27>cd Scripts

C:\Python27\Scripts>pip install opencv_python-3.2.0.7-cp27-cp27m-win32.whl
Processing c:\python27\scripts\opencv_python-3.2.0.7-cp27-cp27m-win32.whl
Requirement already satisfied: numpy>=1.11.1 in c:\python27\lib\site-packages (from opencv-python==3.2.0.7)
Installing collected packages: opencv-python
Successfully installed opencv-python-3.2.0.7

C:\Python27\Scripts>python
Python 2.7.13 (v2.7.13:a06454b1afa1, Dec 17 2016, 20:42:59) [MSC v.1500 32 bit (Intel)] on win32
Type "help", "copyright", "credits" or "license" for more information.
Let's test it with default source code:

>>> import cv2
>>> dir(cv2)
['', 'ACCESS_FAST', 'ACCESS_MASK', 'ACCESS_READ', 'ACCESS_RW', 'ACCESS_WRITE', 
'ADAPTIVE_THRESH_GAUSSIAN_C', 'ADAPTIVE_THRESH_MEAN_C', 'AGAST_FEATURE_DETECTOR_AGAST_5_8', 
'AGAST_FEATURE_DETECTOR_AGAST_7_12D', 'AGAST_FEATURE_DETECTOR_AGAST_7_12S',
 'AGAST_FEATURE_DETECTOR_NONMAX_SUPPRESSION', 'AGAST_FEATURE_DETECTOR_OAST_9_16',
...
Now we can test this python script example with PyQt4 python module and cv2.resize function very easy.
The example load a image with PyQt4 python module.
from PyQt4.QtGui import QApplication, QWidget, QVBoxLayout, QImage, QPixmap, QLabel, QPushButton, QFileDialog
import cv2
import sys
app = QApplication([])
window = QWidget()
layout = QVBoxLayout(window)
window.setLayout(layout)
display = QLabel()
width = 600
height = 400
display.setMinimumSize(width, height)
layout.addWidget(display)
button = QPushButton('Load', window)
layout.addWidget(button)

def read_image():
    path = QFileDialog.getOpenFileName(window)
    if path:
        print str(path)
        picture = cv2.imread(str(path))
        if picture is not None:
            print width, height
            picture = cv2.resize(picture, (width, height))
            image = QImage(picture.tobytes(),  # The content of the image
                           picture.shape[1],  # The width (number of columns)
                           picture.shape[0],  # The height (number of rows)
                           QImage.Format_RGB888)  # The image is stored in 3*8-bit format
            display.setPixmap(QPixmap.fromImage(image.rgbSwapped()))
        else:
            display.setPixmap(QPixmap())

button.clicked.connect(read_image)
window.show()

app.exec_()
See the result for this python script: