camtest.py

import SimpleCV as scv
import pygame
import sys

BLACK = (0, 0, 0)
RED = (255, 0, 0)

SCALE = 0.25

cam = scv.Camera()

pygame.init()
screen = pygame.display.set_mode([800, 600])
screen.fill(BLACK)

def get_faces(img, scale, feature='face'):
    features = img.scale(scale).findHaarFeatures(feature + '.xml')
    
    output = []
    if features is not None:
        for feature in features:
            scale = round(1 / scale)
            x, y = feature.topLeftCorner()
            output.append({
                'height': feature.height() * scale,
                'width': feature.width() * scale,
                'top_left_x': x * scale,
                'top_right_x': y * scale,
                'center_x': feature.x * scale,
                'center_y': feature.y * scale,
                'full_feature': feature
            })
    
    return output
    
while True:
    img = cam.getImage()
    
    screen.fill(BLACK)
    screen.blit(img.getPGSurface(), (0,0))
    
    faces = get_faces(img, SCALE)
    for face in faces:
        pygame.draw.rect(
            screen,
            RED,
            pygame.Rect(
                face['top_left_x'], 
                face['top_right_x'], 
                face['width'], 
                face['height']),
            5)
            
    pygame.display.flip()
    
    event = pygame.event.poll()
    if event.type == pygame.QUIT:
        pygame.quit()
        sys.exit()