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pgorczak/imgmatrix.py

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Revisions

  1. pgorczak revised this gist Aug 31, 2015. No changes.
  2. pgorczak revised this gist Aug 31, 2015. No changes.
  3. pgorczak revised this gist Aug 31, 2015. No changes.
  4. pgorczak revised this gist Aug 31, 2015. No changes.
  5. pgorczak created this gist Aug 31, 2015.
    63 changes: 63 additions & 0 deletions imgmatrix.py
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    #! /usr/bin/env python

    import argparse
    import itertools

    import cv2
    import numpy as np

    if __name__=='__main__':
    parser = argparse.ArgumentParser(
    description='Arrange a number of images as a matrix.')
    parser.add_argument('f', help='Output filename.')
    parser.add_argument('w', type=int,
    help='Width of the matrix (number of images).')
    parser.add_argument('h', type=int,
    help='Height of the matrix (number of images).')
    parser.add_argument('img', nargs='+', help='Images (w x h files).')
    parser.add_argument('--margin', metavar='m', nargs=1,
    help='Margin between images: integers are '
    'interpreted as pixels, floats as proportions.')
    args = parser.parse_args()

    w = args.w
    h = args.h
    n = w*h

    if len(args.img) != n:
    raise ValueError('Number of images ({}) does not match '
    'matrix size {}x{}'.format(w, h, len(args.img)))

    imgs = [cv2.imread(i) for i in args.img]

    if any(i.shape != imgs[0].shape for i in imgs[1:]):
    raise ValueError('Not all images have the same shape.')

    img_h, img_w, img_c = imgs[0].shape

    m_x = 0
    m_y = 0
    if args.margin is not None:
    margin = args.margin[0]
    if '.' in margin:
    m = float(margin)
    m_x = int(m*img_w)
    m_y = int(m*img_h)
    else:
    m_x = int(margin)
    m_y = m_x

    imgmatrix = np.zeros((img_h * h + m_y * (h - 1),
    img_w * w + m_x * (w - 1),
    img_c),
    np.uint8)

    imgmatrix.fill(255)

    positions = itertools.product(range(w), range(h))
    for (x_i, y_i), img in itertools.izip(positions, imgs):
    x = x_i * (img_w + m_x)
    y = y_i * (img_h + m_y)
    imgmatrix[y:y+img_h, x:x+img_w, :] = img

    cv2.imwrite(args.f, imgmatrix)