Install Python

Python may already be installed.

For Windows, Python can be downloaded from here https://www.python.org/downloads/windows/. Typically the best one is Python 3 in Stable Releases and is 64-bit.

For Ubuntu, Python 3 is typically already installed. Ubuntu requires the "python3" command to run the software.

If you don't have it, it can be installed from www.python.org.

Install Packages

The first demonstration programs do not require installing packages.
Using Jupyter does not require installing packages.
Install pip using instructions here https://pip.pypa.io/en/stable/installing/

Install pygame

For Ubuntu, open a terminal and run:


    $ pip3 install python3-pygame


    $ sudo apt-get install python3-pygame

Or follow the instructions here: www.pygame.org/wiki/GettingStarted

Install opencv

This is only required for programs in the image-proc folder.

For Ubuntu, open a terminal and run:


    $ pip3 install python3-opencv


    $ sudo apt-get install python3-opencv

Or follow the instructions here: https://docs.opencv.org/master/d2/de6/tutorial_py_setup_in_ubuntu.html
Or here: https://docs.opencv.org/master/d5/de5/tutorial_py_setup_in_windows.html

Open a Command Console or Terminal

For Ubuntu:

Click on the "Files" icon (File Folder Viewer) on the left side of the screen. Or run Activities and enter "Nautilus".
Click on folders in the "explorer"
Once the correct folder is selected, then right click with the mouse and select, "Open in Terminal"
Then the prompt is displayed. If there are instructions such as, "$ ls *", the "$" part should not be entered since it is indicating the prompt that is displayed.

Running Programs

There are many ways to run the Python demo programs.

Python program can be run from the Idle program.

Python programs can be run from a terminal. First open a terminal, and then enter the text required to run the program. In the Demos documentation, the text to run is shown.

Another way is to right click on the file that you would like to edit and run, then select "Open With Other Application", then select "Idle". Then select "Run/Run Module" or the key F5.

The demo programs can also be run from Jupyter.

Editing Programs

Editing Python programs can be done with any text editor. The default Python editor is "Idle" and has colored text so that it is easier to read.

For Ubuntu:

Right click on a .py file.
Select "Open with Other Application"
Select "Idle"

The menu Run/Run Module will run the program. The Python Shell may not show anything, but most demos will show a new window somewhere on the screen.

Solving Problems

Often searching on the internet will help to find out how to solve a problem. Other types of problems require debugging.

Debugging Programs

It is possible to debug Python programs by inserting statements into the program. Some examples are:

Statement	Description
print('1')	This will print a "1" to the terminal when the print statement is run.
print(object)	This will print the content values of an object or variable
print(dir(object))	This will print the methods or members of an object or variable
print(type(object))	This will print the type of an object or variable
print('place1', str(obj))	This will print 'place1' and information about an object.

There are some Python editors that allow debugging. Search the internet for "Python IDE" to find different editors.

Grab a Screenshot (Image)

An image can be saved of the current screen or window.

For Ubuntu:

Click on the "Activities" menu.
Enter "Screenshot" in the "Type to Search" box.
Click "Take Screenshot"

Grab a Screencast (Video)

A movie can be saved of the activities during some animation, or selections on the screen. For Ubuntu:

Click on the "Activities" menu.
Enter "Screenshot" in the "Type to Search" box.
Enter a delay of a few seconds.
Press Ctrl-Alt-Shift-R to start recording.
Run your program.
Press Ctrl-Alt-Shift-R to stop recording.
The output file is saved in home directory in the "Videos" folder.

Edit Video with WinFF or ffmpeg

Install "WinFF" using Synaptic or command line. A video can also be edited in Gimp to change individual frames.

Cut and Crop

Run WinFF
Click the Options. This will show extra tabs in the screen.
Use the Crop tab to indicate how many pixels to remove from each side.
Use the Time tab to select when to start keeping the video and how much to keep.
Use Preview to view the changes.
Use Convert to save the file in the home directory.

It seems like both Crop and changing the video size don't work at the same time. So load the already cropped video, and use the Video tab to set the output size.

Set Image Size

A complete example for the game/bug-data/Bug-Source/Bug.mp4 is:

Video: Frame Rate=5, Video Size=100 X -1
Time: Seek to=5, Time to Record=6

Extract Frames

To extract frames, first open a terminal, and then run:


/usr/bin/ffmpeg -i "/dir/game/bug-data/Bug.mp4" /dir/game/bug-data/Bug/frame_%03d.png

The dir in italics must be replaced with your actual folder.