Fix bug in __init_memmap for Windows OS

[EdjeElectronics]

While using PyBoof, I encountered the following error when trying to load an image and perform QR code detection on it:

...
File "C:\Users\taxig\anaconda3\envs\tavolo-env1\lib\site-packages\pyboof\common.py", line 179, in mmap_array_java_to_python
    mm.seek(0)
AttributeError: 'NoneType' object has no attribute 'seek'

The code I used to produce the bug is shown at the end of this post.

After digging, I found that the mmap_file global object is not intialized correctly for the Windows NT branch of code in the def __init_memmap function in __init__.py. It should be pbg.mmap_file instead of just mmap_file. (Note that the non-Windows NT code uses pbg.mmap_file.

When I changed mmap_file to pbg.mmap_file, the bug went away.

Code to reproduce bug:

# Testing pyboof library

import pyboof as pb
import numpy as np
import os

# Get path to image file
cwd = os.getcwd()
pic_fn = 'test_pic.png'
pic_path = os.path.join(cwd,pic_fn)

# Load image file with pyboof
img = pb.load_single_band(pic_path, np.uint8)

# Initialize QR code detector
detector = pb.FactoryFiducial(np.uint8).qrcode()

# Detect QR codes
detector.detect(img)
print('Detected a total of %d QR Codes' % (len(detector.detections)))
for qr in detector.detections:
    print("Message: " + qr.message)
    print("     at: " + str(qr.bounds))