cv::threshold(src, src, 40, 255, 1)中的1是什么意思
时间: 2024-04-12 18:34:19 浏览: 15
在cv::threshold()函数中,第五个参数用于指定阈值类型。当参数值为1时,表示阈值类型为cv::THRESH_BINARY_INV。
具体而言,cv::THRESH_BINARY_INV与cv::THRESH_BINARY不同,它执行了相反的操作。当像素值大于阈值时,将像素值设置为0,否则将像素值设置为最大值(在这里是255)。因此,该函数将图像转换为反转的二进制图像,其中大于阈值的像素被设置为0,小于或等于阈值的像素被设置为255。
相关问题
cv::threshold(src, src, 40, 255, 0)中的0是什么意思
在 OpenCV 中,函数 `cv::threshold()` 用于对图像进行二值化处理。其中的参数 `0` 是用来指定二值化的类型的。
具体而言,参数 `0` 对应的是 `cv::THRESH_BINARY`,表示将大于阈值的像素值设置为最大值(在此例中为 255),而小于等于阈值的像素值设置为 0。
如果你想使用其他的二值化类型,可以参考以下选项:
- `cv::THRESH_BINARY_INV`:将小于阈值的像素值设置为最大值,大于等于阈值的像素值设置为 0。
- `cv::THRESH_TRUNC`:将大于阈值的像素值截断为阈值,小于等于阈值的像素值保持不变。
- `cv::THRESH_TOZERO`:将小于阈值的像素值设置为 0,大于等于阈值的像素值保持不变。
- `cv::THRESH_TOZERO_INV`:将大于阈值的像素值设置为 0,小于等于阈值的像素值保持不变。
希望这能解答你的问题!如果还有其他疑问,请随时提问。
(-215:Assertion failed) src.type() == CV_8UC1 in function 'cv::threshold'
This error message is related to OpenCV and it indicates that the input image passed to the threshold function is not of the expected type. The threshold function expects a single-channel (grayscale) image with pixel values of type unsigned 8-bit integer (CV_8UC1).
To fix this error, you should first check that the input image is a grayscale image with a single channel. If the input image is a color image or has more than one channel, you should convert it to grayscale using cvtColor() function.
You should also make sure that the pixel values in the image are of type unsigned 8-bit integer. If the pixel values are not of this type, you can use the convertTo() function to convert the pixel values to the correct type.
Here's an example of how to convert an input image to grayscale and convert the pixel values to unsigned 8-bit integer:
```
cv::Mat input_image = cv::imread("input_image.jpg");
cv::Mat gray_image;
cv::cvtColor(input_image, gray_image, cv::COLOR_BGR2GRAY);
cv::Mat threshold_image;
gray_image.convertTo(threshold_image, CV_8UC1);
cv::threshold(threshold_image, threshold_image, 128, 255, cv::THRESH_BINARY);
```