PROSAGA码农传奇-模式识别-如何使用openCV提高Python内视频播放的速度

如何使用openCV提高Python内视频播放的速度

作者: 筱梨
发布时间: 2024-01-22 02:21:00 (5月前)
转自：

<div class =“post-text”itemprop =“text”>
  <P>
    这就是问题...
  </p>
   <pre>
    <code>
      for x in range(width):
    for y in range(height):
         if canny[y,x] == 255:

</code>
  </pre>
  <P>
    Numpy.argmax是解决方案......
  </p>
   <pre>
    <code>
      for x in range(width-1):
    # Slice the relevant column from the image
    # The image 'column' is a tall skinny image, only 1px thick
    column = np.array(canny[:,x:x+1])
    # Use numpy to find the first non-zero value
    railPoint = np.argmax(column)

</code>
  </pre>
  <P>
    完整代码：
  </p>
   <pre>
    <code>
      import cv2, numpy as np, time
# Get start time
start = time.time()
# Read in the image
img = cv2.imread('/home/stephen/Desktop/rail.jpg')[40:,10:-10]
# Canny filter
canny = cv2.Canny(img, 85, 255)
# Get height and width
height, width = canny.shape
# Create list to store rail points
railPoints = []
# Iterate though each column in the image
for position in range(width-1):
    # Slice the relevant column from the image
    # The image 'column' is a tall skinny image, only 1px thick
    column = np.array(canny[:,position:position+1])
    # Use numpy to find the first non-zero value
    railPoint = np.argmax(column)
    # Add the railPoint to the list of rail points
    railPoints.append(railPoint)
    # Draw a circle on the image
    cv2.circle(img, (position, railPoint), 1, (123,234,123), 2)
cv2.imshow('img', img)                      
k = cv2.waitKey(1)
cv2.destroyAllWindows()
print(time.time() - start)

</code>
  </pre>
  <P>
    我使用Numpy的解决方案需要6毫秒，而你的解决方案需要266毫秒。