使用cv2.imread的屏幕截图和语法错误

Question

I'm new to python and OPENCV and I need to write a python code that reads an image. I used some examples I've found online and I get some strange results.

Im running ubuntu12.04 and opencv2.4.9
First, when I run the file my mouse turn to cross wait for my input (4 clicks).
Second, I get a syntax massage that I can't find what is wrong in my code.
And the last one, when I look in the folder of the py file I see 2 new files:
"cv2" -A screenshot of my first click and "np" - the other 3 screenshots (the other 3 clicks)

Here is the code:

!/usr/bin/python

import cv2
import numpy as np

Read image

img = cv2.imread('clutter.jpg')

Yellow_MIN = np.array([20, 50, 45],np.uint8)
Yellow_MAX = np.array([30, 255, 255],np.uint8)

hsv_img = cv2.cvtColor(img,cv2.COLOR_BGR2HSV)

frame_threshed = cv2.inRange(hsv_img, Yellow_MIN, Yellow_MAX)
cv2.imwrite('output2.jpg', frame_threshed)

--end of code--

The syntax error is :

./color_find_et.py: line 9: syntax error near unexpected token `('
./color_find_et.py: line 9: `img = cv2.imread('clutter.jpg')'

Answer 1

You need to add the Flags specifying the color type of a loaded image

Use the function cv2.imread() to read an image. The image should be in the working directory or a full path of image should be given.

Second argument is a flag which specifies the way image should be read.

 cv2.IMREAD_COLOR : Loads a color image. Any transparency of image will be neglected. It is the default flag. cv2.IMREAD_GRAYSCALE : Loads image in grayscale mode cv2.IMREAD_UNCHANGED : Loads image as such including alpha channel 

Note

Instead of these three flags, you can simply pass integers 1, 0 or -1 respectively.

specifically your code needs to be:

 img = cv2.imread('clutter.jpg', 0)

Answer 2

Instead of writing "import cv2" you have to write

"from cv2 import * "