openCV—访问与操作像素（图片的区域的更改）

<code class="hljs perl has-numbering" style="display: block; padding: 0px; background: transparent; color: inherit; box-sizing: border-box; font-family: "Source Code Pro", monospace;font-size:undefined; white-space: pre; border-radius: 0px; word-wrap: normal;"><span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">#encoding:utf-8</span>

import cv2

image = cv2.imread(<span class="hljs-string" style="color: rgb(0, 136, 0); box-sizing: border-box;">"H:\\img\\lena.jpg"</span>)<span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">#读取图像</span>

(b,g,r) = image[<span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">0</span>,<span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">0</span>]<span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">#读取(0,0)像素，Python中图像像素是按B,G,R顺序存储的</span>
<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">print</span> <span class="hljs-string" style="color: rgb(0, 136, 0); box-sizing: border-box;">"位置(0,0)处的像素 - 红:<span class="hljs-variable" style="color: rgb(102, 0, 102); box-sizing: border-box;">%d</span>,绿:<span class="hljs-variable" style="color: rgb(102, 0, 102); box-sizing: border-box;">%d</span>,蓝:<span class="hljs-variable" style="color: rgb(102, 0, 102); box-sizing: border-box;">%d</span>"</span> <span class="hljs-variable" style="color: rgb(102, 0, 102); box-sizing: border-box;">%(</span>r,g,b)<span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">#显示像素值</span>

image[<span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">0</span>,<span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">0</span>] = (<span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">100</span>,<span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">150</span>,<span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">200</span>)<span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">#更改位置(0,0)处的像素</span>

(b,g,r) = image[<span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">0</span>,<span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">0</span>]<span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">#再次读取(0,0)像素</span>
<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">print</span> <span class="hljs-string" style="color: rgb(0, 136, 0); box-sizing: border-box;">"位置(0,0)处的像素 - 红:<span class="hljs-variable" style="color: rgb(102, 0, 102); box-sizing: border-box;">%d</span>,绿:<span class="hljs-variable" style="color: rgb(102, 0, 102); box-sizing: border-box;">%d</span>,蓝:<span class="hljs-variable" style="color: rgb(102, 0, 102); box-sizing: border-box;">%d</span>"</span> <span class="hljs-variable" style="color: rgb(102, 0, 102); box-sizing: border-box;">%(</span>r,g,b)<span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">#显示更改后的像素值</span>

corner = image[<span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">0</span>:<span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">100</span>,<span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">0</span>:<span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">100</span>]<span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">#读取像素块</span>
cv2.imshow(<span class="hljs-string" style="color: rgb(0, 136, 0); box-sizing: border-box;">"Corner"</span>,corner)<span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">#显示读取的像素块</span>

image[<span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">0</span>:<span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">100</span>,<span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">0</span>:<span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">100</span>] = (<span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">0</span>,<span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">255</span>,<span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">0</span>);<span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">#更改读取的像素块</span>

cv2.imshow(<span class="hljs-string" style="color: rgb(0, 136, 0); box-sizing: border-box;">"Updated"</span>,image)<span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">#显示图像</span>

cv2.waitKey(<span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">0</span>)<span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">#程序暂停</span></code><ul class="pre-numbering eye-protector-processed" style="box-sizing: border-box; position: absolute; width: 50px; background-color: rgb(193, 230, 198); top: 0px; left: 0px; margin: 0px; padding: 6px 0px 40px; border-right: 1px solid rgba(0, 0, 0, 0.34902); list-style: none; text-align: right; transition: background 0.3s ease;"><li style="box-sizing: border-box; padding: 0px 5px;">1</li><li style="box-sizing: border-box; padding: 0px 5px;">2</li><li style="box-sizing: border-box; padding: 0px 5px;">3</li><li style="box-sizing: border-box; padding: 0px 5px;">4</li><li style="box-sizing: border-box; padding: 0px 5px;">5</li><li style="box-sizing: border-box; padding: 0px 5px;">6</li><li style="box-sizing: border-box; padding: 0px 5px;">7</li><li style="box-sizing: border-box; padding: 0px 5px;">8</li><li style="box-sizing: border-box; padding: 0px 5px;">9</li><li style="box-sizing: border-box; padding: 0px 5px;">10</li><li style="box-sizing: border-box; padding: 0px 5px;">11</li><li style="box-sizing: border-box; padding: 0px 5px;">12</li><li style="box-sizing: border-box; padding: 0px 5px;">13</li><li style="box-sizing: border-box; padding: 0px 5px;">14</li><li style="box-sizing: border-box; padding: 0px 5px;">15</li><li style="box-sizing: border-box; padding: 0px 5px;">16</li><li style="box-sizing: border-box; padding: 0px 5px;">17</li><li style="box-sizing: border-box; padding: 0px 5px;">18</li><li style="box-sizing: border-box; padding: 0px 5px;">19</li><li style="box-sizing: border-box; padding: 0px 5px;">20</li><li style="box-sizing: border-box; padding: 0px 5px;">21</li><li style="box-sizing: border-box; padding: 0px 5px;">22</li></ul><ul class="pre-numbering eye-protector-processed" style="box-sizing: border-box; position: absolute; width: 50px; background-color: rgb(193, 230, 198); top: 0px; left: 0px; margin: 0px; padding: 6px 0px 40px; border-right: 1px solid rgba(0, 0, 0, 0.34902); list-style: none; text-align: right; transition: background 0.3s ease;"><li style="box-sizing: border-box; padding: 0px 5px;">1</li><li style="box-sizing: border-box; padding: 0px 5px;">2</li><li style="box-sizing: border-box; padding: 0px 5px;">3</li><li style="box-sizing: border-box; padding: 0px 5px;">4</li><li style="box-sizing: border-box; padding: 0px 5px;">5</li><li style="box-sizing: border-box; padding: 0px 5px;">6</li><li style="box-sizing: border-box; padding: 0px 5px;">7</li><li style="box-sizing: border-box; padding: 0px 5px;">8</li><li style="box-sizing: border-box; padding: 0px 5px;">9</li><li style="box-sizing: border-box; padding: 0px 5px;">10</li><li style="box-sizing: border-box; padding: 0px 5px;">11</li><li style="box-sizing: border-box; padding: 0px 5px;">12</li><li style="box-sizing: border-box; padding: 0px 5px;">13</li><li style="box-sizing: border-box; padding: 0px 5px;">14</li><li style="box-sizing: border-box; padding: 0px 5px;">15</li><li style="box-sizing: border-box; padding: 0px 5px;">16</li><li style="box-sizing: border-box; padding: 0px 5px;">17</li><li style="box-sizing: border-box; padding: 0px 5px;">18</li><li style="box-sizing: border-box; padding: 0px 5px;">19</li><li style="box-sizing: border-box; padding: 0px 5px;">20</li><li style="box-sizing: border-box; padding: 0px 5px;">21</li><li style="box-sizing: border-box; padding: 0px 5px;">22</li></ul>