python - dct 中的断言失败(类型 == CV_32FC1 || 类型 == CV_64FC1)

Question

我正在尝试获取图像的 dct。一开始我遇到了错误

The function/feature is not implemented (Odd-size DCT's are not implemented) in dct

所以我用零填充图像以使其大小均匀

但现在我得到错误:

Assertion failed (type == CV_32FC1 || type == CV_64FC1) in dct

我该如何解决这个问题？下面是我在 python 中所做的

    img = cv2.imread(filepath)
    gray = cv2.cvtColor(img, cv2.COLOR_BGR2GRAY)
    ret,thresholded = cv2.threshold(gray,200,255,cv2.THRESH_BINARY)

    img = cv2.cvtColor(thresholded, cv2.COLOR_GRAY2BGR)
    gray = thresholded
    gray = gray.astype('float32')

    #padding
    BLUE = [255,0,0]
    rows,cols = gray.shape
    nrows = cv2.getOptimalDFTSize(rows)
    ncols = cv2.getOptimalDFTSize(cols)
    right = ncols - cols
    bottom = nrows - rows
    bordertype = cv2.BORDER_CONSTANT
    gray = cv2.copyMakeBorder(img,0,bottom,0,right,bordertype, value = 0)
    gray = gray.astype('float32')
    dct=cv2.dct(gray)

Answer 1

import cv2
import numpy as np
img = cv2.imread('imgColor.jpg')
gray = cv2.cvtColor(img, cv2.COLOR_BGR2GRAY)

ret,thresholded = cv2.threshold(gray,200,255,cv2.THRESH_BINARY)

img = cv2.cvtColor(thresholded, cv2.COLOR_GRAY2BGR)
gray = thresholded
gray = np.float32(gray)/255.0
dct=cv2.dct(gray)

#padding
# BLUE = [255,0,0]
# rows,cols = gray.shape
# nrows = cv2.getOptimalDFTSize(rows)
# ncols = cv2.getOptimalDFTSize(cols)
# right = ncols - cols
# bottom = nrows - rows
# bordertype = cv2.BORDER_CONSTANT
# gray = cv2.copyMakeBorder(img,0,bottom,0,right,bordertype, value = 0)
# gray = np.float32(gray)/255.0
# dct=cv2.dct(gray)

这对我有用!找到这个here