Python OpenCV如何改善SIFT输出？

Question

        train_image = 'train_image location'
        sift = cv2.SIFT_create() 
        gray = cv2.cvtColor(train_image, cv2.COLOR_BGR2GRAY)
        (kp, descs) = sift.detectAndCompute(gray, None)
      

我为火车型号提供了39,209个流量标志图片的数据集。当我尝试从他们那里获得筛选功能3131时无法创建desc。在尝试调整此代码有问题的图像大小后，

resized = cv2.resize(train_image,(256,256))

数字从3131下降到2613。更好的 ？

Answer 1

              resized = cv2.resize(roi_image,(256,256))
              alpha = 2.5 # Contrast control (1.0-3.0)
              beta = 50 # Brightness control (0-100)
              adjusted = cv2.convertScaleAbs(resized, alpha=alpha, beta=beta)
              sift = cv2.SIFT_create() 
              gray = cv2.cvtColor(adjusted, cv2.COLOR_BGR2GRAY)
              (kp, descs) = sift.detectAndCompute(gray, None)

我发现改变亮度和对比可能会有所帮助。
麻烦的数据从2613下降到Araound 300。