Setting up the app

In order to run our app, we will need to execute a main function routine that reads a frame of a video stream, generates a saliency map, extracts the location of the proto-objects, and tracks these locations from one frame to the next.

The main function routine

The main process flow is handled by the main function in chapter5.py, which instantiates the two classes (Saliency and MultipleObjectTracker) and opens a video file showing the number of soccer players on the field:

import cv2
import numpy as np
from os import path

from saliency import Saliency
from tracking import MultipleObjectsTracker


def main(video_file='soccer.avi', roi=((140, 100), (500, 600))):
    if path.isfile(video_file):
        video = cv2.VideoCapture(video_file)
    else:
        print 'File "' + video_file + '" does not exist.'
        raise SystemExit

    # initialize tracker
    mot = MultipleObjectsTracker()

The function will then read the video frame by frame, extract some meaningful region of...