Python OpenCV TypeError：参数“src”的预期 cv::UMat - 这是什么？
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OpenCV TypeError: Expected cv::UMat for argument 'src' - What is this?
提问by autonocat
Disclaimer: huge openCV noob
免责声明：巨大的 openCV 菜鸟
Traceback (most recent call last):
File "lanes2.py", line 22, in
canny = canny(lane_image)File "lanes2.py", line 5, in canny
gray = cv2.cvtColor(imgUMat, cv2.COLOR_RGB2GRAY)TypeError: Expected cv::UMat for argument 'src'
回溯（最近一次调用最后一次）：
文件“lanes2.py”，第 22 行，在
canny = canny(lane_image)文件“lanes2.py”，第 5 行，canny
gray = cv2.cvtColor(imgUMat, cv2.COLOR_RGB2GRAY)类型错误：参数“src”的预期 cv::UMat
What exactly is 'src' referring to?
“src”究竟指的是什么？
回答by Varun Mathur
srcis the first argument to cv2.cvtColor.
src是 的第一个参数cv2.cvtColor。
The error you are getting is because it is not the right form. cv2.Umat()is functionally equivalent to np.float32(), so your last line of code should read:
你得到的错误是因为它不是正确的形式。cv2.Umat()在功能上等同于np.float32()，因此您的最后一行代码应为：
gray = (np.float32(imgUMat), cv2.COLOR_RGB2GRAY)
回答by Nuzhny
gray = cv2.cvtColor(cv2.UMat(imgUMat), cv2.COLOR_RGB2GRAY)
UMat is a part of the Transparent API (TAPI)than help to write one code for the CPU and OpenCL implementations.
UMat 是透明 API (TAPI)的一部分，有助于为 CPU 和 OpenCL 实现编写代码。
回答by Avi Avidan
The following can be used from numpy:
可以从以下使用numpy：
import numpy as np
image = np.array(image)
回答by Maximilian
Not your code is the problem this is perfectly fine:
不是你的代码是问题，这完全没问题：
gray = cv2.cvtColor(imgUMat, cv2.COLOR_RGB2GRAY)
The problem is that imgUMat is Noneso you probably made a mistake when loading your image:
问题是 imgUMat 是None这样，您可能在加载图像时犯了一个错误：
imgUMat = cv2.imread("your_image.jpg")
I suspect you just entered the wrong image path.
我怀疑您刚刚输入了错误的图像路径。
回答by Daweo
Is cannyyour own function? Do you use Cannyfrom OpenCV inside it? If yes check if you feed suitable argument for Canny- first Cannyargument should meet following criteria:
是canny你自己的功能吗？你在里面使用OpenCV 的Canny吗？如果是，请检查您是否提供了合适的参数Canny- 第一个Canny参数应满足以下条件：
- type:
<type 'numpy.ndarray'> - dtype:
dtype('uint8') - being single channel or simplyfing: grayscale,that is 2D array, i.e. its
shapeshould be 2-tupleofints (tuplecontaining exactly 2 integers)
- 类型：
<type 'numpy.ndarray'> - 数据类型：
dtype('uint8') - 为单信道或simplyfing：灰度，即2D阵列，即，其
shape应该是2-tuple的intS（tuple正好含有2个整数）
You can check it by printing respectively
可以分别打印查看
type(variable_name)
variable_name.dtype
variable_name.shape
Replace variable_namewith name of variable you feed as first argument to Canny.
替换variable_name为您作为第一个参数提供的变量名称Canny。
回答by Hazarapet Tunanyan
回答by Oysiyl
Sometimes I have this error when videostreamfrom imutilspackage doesn't recognize frame or give an empty frame. In that case, solution will be figuring out why you have such a bad frame or use a standard VideoCapture(0) method from opencv2
有时，当来自imutils包的视频流无法识别帧或给出空帧时，我会遇到此错误。在这种情况下，解决方案将找出为什么您有如此糟糕的帧或使用来自 opencv2 的标准 VideoCapture(0) 方法
回答by Amar Sagat
Just add this at start: image = cv2.imread(image)
只需在开始时添加： image = cv2.imread(image)
回答by Geo
I got round thid by writing/reading to a file. I guessed cv.imread would put it into the format it needed. This code for anki Vector SDK program but you get the idea.
我通过写入/读取文件来解决问题。我猜 cv.imread 会把它变成它需要的格式。这段代码用于 anki Vector SDK 程序，但您明白了。
tmpImage = robot.camera.latest_image.raw_image.save('temp.png')
pilImage = cv.imread('temp.png')
tmpImage = robots.camera.latest_image.raw_image.save('temp.png')
pilImage = cv.imread('temp.png')
回答by Oliver Zendel
Some dtype are not supported by specific OpenCV functions. For example inputs of dtype np.uint32 create this error. Try to convert the input to a supported dtype (e.g. np.int32 or np.float32)
特定的 OpenCV 函数不支持某些 dtype。例如 dtype np.uint32 的输入会创建此错误。尝试将输入转换为支持的 dtype（例如 np.int32 或 np.float32）
