<h5 dir="auto">System information (version)</h5>

<ul dir="auto">
<li>OpenCV =&gt; 4.1.0</li>
<li>Operating System / Platform =&gt; Mac OS Mojave 10.14</li>
<li>Compiler =&gt; n/a python 3.7</li>
</ul>
<h5 dir="auto">Detailed description</h5>
<p dir="auto"><a href="https://docs.opencv.org/4.1.0/d7/d37/tutorial_mat_mask_operations.html" rel="nofollow">https://docs.opencv.org/4.1.0/d7/d37/tutorial_mat_mask_operations.html</a><br>
python version of tutorial divides 1000 after evaluating current time - start time.  This is incorrect as it will already return seconds,  no need to divide by 1000.</p>

<h5 dir="auto">Steps to reproduce</h5>
<p dir="auto">'''<br>
t = (time.time() - t) / 1000<br>
print("Built-in filter2D time passed in seconds:     %s" % t)<br>
'''</p>
<h5 dir="auto">System information (version)</h5>

<ul dir="auto">
<li>OpenCV =&gt; 4.1.0</li>
<li>Operating System / Platform =&gt; Windows 10 Pro 64bit (10.0, build 17763)</li>
<li>Compiler =&gt; Visual Studio 2017 or Python 2.7.15</li>
</ul>
<h5 dir="auto">Detailed description</h5>
<p dir="auto">When using GaussianBlur, when Width = 5 and SigmaX = 9, strange lines are visible at both ends of the image.</p>
<h5 dir="auto">Steps to reproduce</h5>

<p dir="auto">Source image<br>
<a target="_blank" rel="noopener noreferrer nofollow" href="https://user-images.githubusercontent.com/32478538/61028842-a8bfca80-a3f4-11e9-81ca-b14fe33d1be1.jpg"><img src="https://user-images.githubusercontent.com/32478538/61028842-a8bfca80-a3f4-11e9-81ca-b14fe33d1be1.jpg" alt="test" style="max-width: 100%;"></a></p>
<p dir="auto">Output image<br>
<a target="_blank" rel="noopener noreferrer nofollow" href="https://user-images.githubusercontent.com/32478538/61028846-ab222480-a3f4-11e9-828c-2fb91cc33063.PNG"><img src="https://user-images.githubusercontent.com/32478538/61028846-ab222480-a3f4-11e9-828c-2fb91cc33063.PNG" alt="output" style="max-width: 100%;"></a></p>
<p dir="auto">below code is same thing happens C++.</p>
<div class="highlight highlight-source-python notranslate position-relative overflow-auto" dir="auto" data-snippet-clipboard-copy-content="# coding: utf-8

import numpy as np
import cv2

print('OpenCV version : ' + cv2.__version__)

img = cv2.imread('test.bmp')

gau1 = cv2.GaussianBlur(img, (5,5), 8)
gau2 = cv2.GaussianBlur(img, (5,5), 9)
gau3 = cv2.GaussianBlur(img, (5,5), 10)

cv2.imshow('origin', img)
cv2.imshow('gau1', gau1)
cv2.imshow('gau2', gau2)
cv2.imshow('gau3', gau3)

cv2.waitKey(0)
cv2.destroyAllWindows()"><pre class="notranslate"><span class="pl-c"># coding: utf-8</span>

<span class="pl-k">import</span> <span class="pl-s1">numpy</span> <span class="pl-k">as</span> <span class="pl-s1">np</span>
<span class="pl-k">import</span> <span class="pl-s1">cv2</span>

<span class="pl-en">print</span>(<span class="pl-s">'OpenCV version : '</span> <span class="pl-c1">+</span> <span class="pl-s1">cv2</span>.<span class="pl-s1">__version__</span>)

<span class="pl-s1">img</span> <span class="pl-c1">=</span> <span class="pl-s1">cv2</span>.<span class="pl-en">imread</span>(<span class="pl-s">'test.bmp'</span>)

<span class="pl-s1">gau1</span> <span class="pl-c1">=</span> <span class="pl-s1">cv2</span>.<span class="pl-v">GaussianBlur</span>(<span class="pl-s1">img</span>, (<span class="pl-c1">5</span>,<span class="pl-c1">5</span>), <span class="pl-c1">8</span>)
<span class="pl-s1">gau2</span> <span class="pl-c1">=</span> <span class="pl-s1">cv2</span>.<span class="pl-v">GaussianBlur</span>(<span class="pl-s1">img</span>, (<span class="pl-c1">5</span>,<span class="pl-c1">5</span>), <span class="pl-c1">9</span>)
<span class="pl-s1">gau3</span> <span class="pl-c1">=</span> <span class="pl-s1">cv2</span>.<span class="pl-v">GaussianBlur</span>(<span class="pl-s1">img</span>, (<span class="pl-c1">5</span>,<span class="pl-c1">5</span>), <span class="pl-c1">10</span>)

<span class="pl-s1">cv2</span>.<span class="pl-en">imshow</span>(<span class="pl-s">'origin'</span>, <span class="pl-s1">img</span>)
<span class="pl-s1">cv2</span>.<span class="pl-en">imshow</span>(<span class="pl-s">'gau1'</span>, <span class="pl-s1">gau1</span>)
<span class="pl-s1">cv2</span>.<span class="pl-en">imshow</span>(<span class="pl-s">'gau2'</span>, <span class="pl-s1">gau2</span>)
<span class="pl-s1">cv2</span>.<span class="pl-en">imshow</span>(<span class="pl-s">'gau3'</span>, <span class="pl-s1">gau3</span>)

<span class="pl-s1">cv2</span>.<span class="pl-en">waitKey</span>(<span class="pl-c1">0</span>)
<span class="pl-s1">cv2</span>.<span class="pl-en">destroyAllWindows</span>()</pre></div>