CS 107: Pictures and Sounds: Programming with Multimedia

Spring 2008

Final Programming Project Tips

This page contains some tips for making the creation of your animations and movies go a little more smoothly.

You should write functions to handle the different parts of your movie. At the very least, you should have one function for the title and opening credits, one for the moving objects, and one for the credits at the end. Depending on how you divide up your work, you may then also have a main function that calls these other functions, or different group members may be calling each of these various functions.

The following function may be helpful for writing your pictures to files in sequential order. This functions takes a list of pictures of the sort we generated in Lab 8, and writes all of them to the specified directory. It takes four arguments: the first is the list of pictures, the second is the directory where the pictures should be saved, the third is a string that is used to name the pictures, and the final argument is where the numbering for the frames should begin. It may be useful to start numbering at different points if you have more than one list of pictures you would like to include in your movie. You can start numbering frames from the second list where the frame numbers from the first list left off.



#----------------------------------------------------------------------
#saveMovieToFile - Write a list of pictures to files in order. 
#movie - A list of pictures.   
#dir   - The directory where the pictures should be saved.
#name  - The starting portion of the filenames. For example if name is "box"
#        the filenames will look like "box000.jpg", "box001.jpg" etc. 
#firstFrame - Where to start numbering frames.  For example if this is 4,
#             the first file will be named "box004.jpg". 
#----------------------------------------------------------------------
def saveMovieToFile(movie, dir, name, firstFrame):
  curFrame = firstFrame  
  for index in range(len(movie)):
    if movie[index] != 0:
      curName =dir+ name + "%03i" % curFrame + ".jpg"
      writePictureTo(movie[index], curName)
      curFrame= curFrame+1

Here is an example of calling this function:

>>> saveMovieToFile(movieA, 'M:/CS107/Movies/', 'rectangle', 0)
>>> saveMovieToFile(movieB, 'M:/CS107/Movies/', 'rectangle', 3)

Assuming that movieA and movieB are lists containing three pictures each, the result will be the creation of the following 6 files:

M:/CS107/Movies/rectangle000.jpg
M:/CS107/Movies/rectangle001.jpg
M:/CS107/Movies/rectangle002.jpg
M:/CS107/Movies/rectangle003.jpg (movieB starts here)
M:/CS107/Movies/rectangle004.jpg
M:/CS107/Movies/rectangle005.jpg