Image2BlobParams C++ and python

Zihao_Mu · June 8, 2023, 2:13pm

Python Scalar is different with C++

opened 02:12PM - 08 Jun 23 UTC

bug

### System Information Original link: https://forum.opencv.org/t/image2blobpara…ms-c-and-python/13437?u=zihao_mu My code in python : ```py paramTF2cedn = cv.dnn.Image2BlobParams() paramTF2cedn.datalayout = cv.dnn.DNN_LAYOUT_NHWC; paramTF2cedn.ddepth = cv.CV_32F; paramTF2cedn.mean = (128, 128, 128) paramTF2cedn.scalefactor = 1 / 128. paramTF2cedn.size = (224, 224) paramTF2cedn.swapRB = False; paramTF2cedn.paddingmode = cv.dnn.DNN_PMODE_NULL print("paramTF2cedn.scalefactor = ", paramTF2cedn.scalefactor) ``` result is ```paramTF2cedn.scalefactor = (0.0078125, 1.0, 1.0, 1.0)``` in C++ ```cpp Image2BlobParams paramTF2cedn; paramTF2cedn.datalayout = DNN_LAYOUT_NHWC; paramTF2cedn.ddepth = CV_32F; paramTF2cedn.mean = (128, 128, 128); paramTF2cedn.scalefactor = 1 / 128.; paramTF2cedn.size = Size(224, 224); paramTF2cedn.swapRB = false; paramTF2cedn.paddingmode = DNN_PMODE_NULL; cout << "paramTF2cedn.scalefactor = " << paramTF2cedn.scalefactor << endl; ``` result is ```paramTF2cedn.scalefactor = [0.0078125, 0, 0, 0]``` ### Detailed description It is about opencv-python bing. ### Steps to reproduce install lastest opencv-python `pip install opencv-python-rolling==4.7.0.20230603`. ```py param = cv.dnn.Image2BlobParams() param.mean = np.array([0.2, 0.3, 0.4]) # [0.2, 0.3, 0.4, 0.0] # then redefine it. param.mean = 1.0 # it is [1.0, 0.3, 0.4, 0.0] <<-- ``` ### Issue submission checklist - [X] I report the issue, it's not a question - [X] I checked the problem with documentation, FAQ, open issues, forum.opencv.org, Stack Overflow, etc and have not found any solution - [X] I updated to the latest OpenCV version and the issue is still there - [ ] There is reproducer code and related data files (videos, images, onnx, etc)

I have create issue for it, and look forward any reply,

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Image2BlobParams C++ and python

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