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POPython's OpenCV cv2.imread always returns None and cvFeatDetector crashes python
 

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  1. POPython's OpenCV cv2.imread always returns None and cvFeatDetector crashes python
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    <p>I'm getting my feet wet with opencv in python, and I figure a good place to start is loading an image. </p> <p>I've built opencv on my system, and have the python bindings and opencv dlls in the directory tpl/opencv, which is relative to my project. </p> <p>Here is some code that demonstrates the problem: </p> <pre><code>from tpl.opencv import cv2 from tpl.opencv.cv2 import cv from PIL import Image pil_img = Image.open('C:/test_file.jpg') #Read a temp file, the input is actually a computed image chip tmpname = 'C:/tmp.png' pil_img.save(tmpname,'PNG') # Write the image chip to disk im = cv.LoadImage(tmpname) # This seems to work im2 = cv2.imread(tmpname) # This always returns None </code></pre> <p>There is no error message, im2 is just always None. Could I have messed something up with the way I'm importing opencv? Is there a simple workaround? </p> <p>When I create </p> <pre><code> cvFeatDetector = cv2.FeatureDetector_create("MSER") </code></pre> <p>I get , so that part of cv2 seems to work </p> <hr> <p>As a workaround I just loaded the image with numpy</p> <pre><code> im2 = numpy.imread(inname) im = cv2.cvtColor(im2, cv2.COLOR_BGR2GRAY) # This works. I was able to imshow it too cvFeatDetector = cv2.FeatureDetector_create("MSER") # Seems to produce a valid object cvFeatExtractor = cv2.DescriptorExtractor_create("SIFT") # Seems to produce a valid object kpts = cvFeatDetector.detect(im) # Crashes python </code></pre> <p>I find this very odd, because cv2.cvtColor converts the image successfully to grayscale. So some cv2 functions do work, and others fail to varying degrees. </p> <hr> <p>Edit. I fixed this by installing the released 2.4 of opencv. </p>
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    1. COCould you submit a bug on http://code.opencv.org with your png image and the output of `cv2.getBuildInformation()` in attachment?
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      1. USAndrey Kamaev
 

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