Question

不太确定我哪里出错了 - 我正在尝试用我自己拍摄的+/-图像训练OpenCV进行物体检测。所有步骤都可以正常工作，但最终我的Python脚本不会读取我的XML级联文件（但会加载其中一个内置的人脸检测文件）。

对于它的价值，我在Mac Lion上运行Python 2.7.3。

我的流程：

在正图像上创建一个带有边界框的集合文件
创建负片图像列表
使用以下命令opencv_createsamples使用opencv_createsamples -info collection.txt -bg negativeImages.txt -vec positiveVectorFile.vec -num 20 -w 32 -h 24：traincascade
检查矢量文件：图像有点挤压但看起来不错
使用以下命令运行opencv_traincascade -data directoryToStoreFiles -vec positiveVectorFile.vec -bg negativeImageList.txt -numPos 16 -numNeg 20 -numStages 5 -mem 1000 -maxHitRate 0.95 -w 32 -h 24程序：import cv img = cv.LoadImage("test.jpg", 0) # load detection file (various files for different views and uses) cascade = cv.Load("cascade.xml") # doesn't work #cascade = cv.Load("frontalface.xml") # works # detect faces, return as list detected = cv.HaarDetectObjects(img, cascade, cv.CreateMemStorage()) # iterate detected objects, drawing a rectangle around each for (x,y, w,h), n in detected: cv.Rectangle(img, (x,y), (x+w, y+h), 255) # create a window to display the results windowTitle = "Test Cascade" cv.NamedWindow(windowTitle, cv.CV_WINDOW_AUTOSIZE) # display tested image until the escape key is pressed while True: cv.ShowImage(windowTitle, img) # watch for escape key (ASCII 20) key = cv.WaitKey(20) if key == 27: # save the image to file is specified if saveIt == True: cv.SaveImage("detected.png", img) # ... and quit exit()

然后我运行以下Python脚本（使用通常的面部检测XML）：

cv2.error: The node does not represent a user object (unknown type?)

结果是错误： {{1}}

我在这里上传了级联文件：http://pastebin.com/w7uRjyN7。不确定这是我的级联文件，还是其他一些问题，还是一些明显的问题？

Answer 1

好吧，看来cyberdecker的建议是一些问题：cv2对所有的命令完全不同，并且在使用opencv_traincascade时是必需的。我的代码现在有效（虽然我的级联还没有）：

#import library - MUST use cv2 if using opencv_traincascade
import cv2

# rectangle color and stroke
color = (0,0,255)       # reverse of RGB (B,G,R) - weird
strokeWeight = 1        # thickness of outline

# set window name
windowName = "Object Detection"

# load an image to search for faces
img = cv2.imread("test.jpg")

# load detection file (various files for different views and uses)
cascade = cv2.CascadeClassifier("cascade.xml")

# preprocessing, as suggested by: http://www.bytefish.de/wiki/opencv/object_detection
# img_copy = cv2.resize(img, (img.shape[1]/2, img.shape[0]/2))
# gray = cv2.cvtColor(img_copy, cv2.COLOR_BGR2GRAY)
# gray = cv2.equalizeHist(gray)

# detect objects, return as list
rects = cascade.detectMultiScale(img)

# display until escape key is hit
while True:

    # get a list of rectangles
    for x,y, width,height in rects:
        cv2.rectangle(img, (x,y), (x+width, y+height), color, strokeWeight)

    # display!
    cv2.imshow(windowName, img)

    # escape key (ASCII 27) closes window
    if cv2.waitKey(20) == 27:
        break

# if esc key is hit, quit!
exit()

Answer 2

我不确定，因为我不使用python-opencv，只使用C ++部分。您确定使用了detectMultiScale的正确包装函数而不是旧的C cvHaarDetect吗？因为您的级联是使用traincascade训练的，它会生成只能使用CascadeClassifier :: detectMultiScale函数的级联。它不适用于cvHaarDetect。

我认为您需要在python中使用的函数是cv2.CascadeClassifier.detectMultiScale，请查看文档here。

OpenCV traincascade XML文件错误

2 个答案: