color_grayscale_images.py

#!/usr/bin/env python
#
# Copyright (c) 2014, Regents of the University of California
# All rights reserved.
#
# Redistribution and use in source and binary forms, with or without
# modification, are permitted provided that the following conditions are met:
#
# - Redistributions of source code must retain the above copyright notice,
#   this list of conditions and the following disclaimer.
# - Redistributions in binary form must reproduce the above copyright notice,
#   this list of conditions and the following disclaimer in the documentation
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# - Neither the name of the University of California, Berkeley nor the names
#   of its contributors may be used to endorse or promote products derived
#   from this software without specific prior written permission.
#
# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
# AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
# ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
# LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
# CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
# SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
# INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
# CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
# ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
# POSSIBILITY OF SUCH DAMAGE.
#
#
# Color grayscale images
#
# by Fernando L. Garcia Bermudez & Yanina S. Bogliotti
#
# created on 2014-1-4
#

import sys, os, traceback
import numpy as np, matplotlib.image as mpim

def main():

    # Check and parse arguments
    if len(sys.argv) < 2:
        print("Not enough arguments given. Need full path for the image file.")
        sys.exit()
    source = sys.argv[1]

    im_colors = { 'r':0, 'g':1, 'b':2}

    for filename in os.listdir(source):
        filepath = source + filename
        if os.path.splitext(filepath)[1] == '.jpg':

            # Load image
            im       = mpim.imread(filepath)
            im_color = im_colors[filename[-5]]

            # Switch color channel
            rows, cols               = im.shape
            im_colored               = np.zeros((rows, cols, 3))
            im_colored[:,:,im_color] = im / 255.

            # Save colored image
            mpim.imsave(os.path.splitext(filepath)[0] + '.png', im_colored,
                                                                format='PNG')

if __name__ == '__main__':
    try:
        main()
        sys.exit(0)
    except SystemExit as e:
        print('\nI: SystemExit: ' + str(e))
    except KeyboardInterrupt:
        print('\nI: KeyboardInterrupt')
    except Exception as e:
        print('\nE: Unexpected exception!\n' + str(e))
        traceback.print_exc()