Distortion

distort.py

#!/usr/bin/env mdl
# -*- coding: utf-8 -*-
# $File: qr.py
# $Author: Xinyu Zhou <zxy@megvii.com>
# Copyright (c) 2015 Megvii Inc. All rights reserved.


import cv2
from scipy.ndimage import interpolation, filters
import numpy as np

rng = np.random.RandomState(42)

img = cv2.imread('qr.png')
h, w, c = img.shape

dsigma = 5
distort = 10

xys = [
    filters.gaussian_filter(xs, dsigma)
    for xs in rng.randn(2, h, w)]

xys = np.array([
    xs * distort / np.amax(xs)
    for xs in xys
])
dx, dy = xys

nxys = np.asarray([(x + dx[x,y], y + dy[x,y])
                        for x in range(h) for y in
                        range(w)]).T
cs = [
    interpolation.map_coordinates(
        g,
        nxys,
        order=3,
        mode='constant',
        cval=0,
    ).reshape(g.shape)
    for g in cv2.split(img)
]

out = cv2.merge(cs)


cv2.imwrite('out.png', out)



# vim: foldmethod=marker