python - 如何将 `cv2.imwrite()` 输出到标准输出？

Question

我想将图像写入标准输出。但我找不到如何让 cv2.imwrite() 支持它。有没有办法将图像写入标准输出？

    cv2.imwrite(sys.stdout, x)
TypeError: expected string or Unicode object, file found

    cv2.imwrite('/dev/stdout', x)
cv2.error: OpenCV(4.1.0) /Users/travis/build/skvark/opencv-python/opencv/modules/imgcodecs/src/loadsave.cpp:662: error: (-2:Unspecified error) could not find a writer for the specified extension in function 'imwrite_'

Answer 1

这样做就可以了:

import cv2
import sys
img = cv2.imread("test.jpg")
sys.stdout.buffer.write(cv2.imencode(".jpg", img)[1].tobytes())

安装了 feh 的快速单行测试:

python -c "import cv2; import sys; img = cv2.imread(\"test.jpg\"); sys.stdout.buffer.write(cv2.imencode(\".jpg\", img)[1].tobytes())" | feh -