Read picasa.ini and show the faces detected by picasa using python and opencv

picasa-opencv.py

import configparser
import cv2
import sys

def coordinates(rect):
    '''
    Translate encoded coordinates from picasa.ini into number array
    '''
    # From 'rect64(x)' to 'x'
    rect = rect[7:]
    rect = rect[:-1]

    # Left pad with zeros just in case
    rect = rect.zfill(16)

    # Convert to int from 0..65535
    part1 = int(rect[:4], 16)
    part2 = int(rect[4:8], 16)
    part3 = int(rect[8:12], 16)
    part4 = int(rect[12:16], 16)
    return [part1, part2, part3, part4]

def render_rect(img, img_w, img_h, coords):

    # Extract variables from parameter
    (x_min, y_min, x_max, y_max) = coords

    # Calculate relative positions from
    x_min = int(img_w * (x_min / 65535))
    y_min = int(img_h * (y_min / 65535))
    x_max = int(img_w * (x_max / 65535))
    y_max = int(img_h * (y_max / 65535))

    # Render the rectangle
    cv2.rectangle(img, (x_min, y_min), (x_max, y_max), (0xff, 0xff, 0xff), 3)

def render_name(img, img_w, img_h, text, coords):

    # Extract variables from parameter
    (x_min, y_min, x_max, _) = coords

    # Calculate the textsize
    textsize = cv2.getTextSize(text, cv2.FONT_HERSHEY_PLAIN, 2, 3)[0]

    # Determine position
    x = int(img_w * ((x_min + ((x_max - x_min) / 2)) / 65535)) - int(textsize[0] / 2)
    y = int(img_h * (y_min / 65535)) + textsize[1] + 10

    # Render text
    cv2.putText(img, text, (x, y), cv2.FONT_HERSHEY_PLAIN, 2, (0xff, 0xff, 0xff), 3)

if len(sys.argv) != 2:
    print('Pass directory to index as argument')
    sys.exit(1)

dir = sys.argv[1]

config = configparser.ConfigParser()
config.read(dir + '/.picasa.ini')

# Build up a dictionary of ID -> Name
dict = {}

# Read Contacts2 section into dictionary
for (id, name) in config.items('Contacts2'):
    dict[id] = name.split(';')[0]

# Prepare window
cv2.namedWindow('image', cv2.WINDOW_NORMAL)
cv2.resizeWindow('image', 1024, 768)

# Read all sections
for s in config.sections():
    key = 0

    # If it wasn't the Contacts2 section ...
    if (s != 'Contacts2'):

        # Read faces info from section
        faces = config[s]['faces']
        if faces:

            # If we have faces, we will show the image
            img = cv2.imread(dir + '/' + s)

            # Read image width and height
            img_h = len(img)
            img_w = len(img[0])

            # Determine faces from the list (semicolon separated)
            l = faces.split(';')
            for face in l:
                # Determine position and ID from list
                (rect,id) = face.split(',')

                # Calculate coordinates
                coords = coordinates(rect)

                # Render name and image border
                render_rect(img, img_w, img_h, coords)
                render_name(img, img_w, img_h, dict[id], coords)

            # Show the actual image
            cv2.imshow('image', img)
            key = cv2.waitKey() & 0xff

    # Abort if 'ESC' was pressed, otherwise continue
    if (key == 27):
        break

# Remove the windows when done
cv2.destroyAllWindows()