reg: broken python sample

[berak]

• OpenCV =>3.4.3 / 3.4.4
• Operating System / Platform => Windows 64 Bit / ubuntu 16
• Compiler => opencv-contrib-python 3.4.4 / 3.4.3 (from pip)

for unknown reason, sample only runs,
if we use cv.reg_MapShift cv.reg_MapperGradShift and cv.reg_MapperPyramid here:

opencv_contrib/modules/reg/samples/reg_shift.py

Lines 10 to 15 in 7670ff2

	mapTest = cv.reg.MapShift(shift)
	img2 = mapTest.warp(img1)
	mapper = cv.reg.MapperGradShift()
	mappPyr = cv.reg.MapperPyramid(mapper)

(underscores instead of dots)
(easy to fix, but the underscores look quite weird to me)

it also segfaults, if it used like this:

 mappPyr = cv.reg_MapperPyramid(cv.reg_MapperGradShift()) 

instead of:

 mapper = cv.reg_MapperGradShift() 
 mappPyr = cv.reg_MapperPyramid(mapper) 

[lostcontrol]

I can confirm this with:

opencv-contrib-python==4.1.0.25
opencv-python==4.1.0.25

[SunilKrSingh]

Hi @lostcontrol
I am new to Open Source. Have worked on only personal projects. I want to solve this issue.
Can you please tell me what exactly I have to do here? Thanks.

P.S. I have used OpenCV before and I am proficient in python.

[lostcontrol]

@SunilKrSingh, I'm not involved in OpenCV but have a look at the first comment and check the sample code. Based on that you should be able to reproduce the issue. Good luck.

[nivedwho]

@alalek This issue has been solved already right?

[Frankie-Machine]

@alalek can i be assigned this issue please?

[berak]

@Frankie-Machine , just try to reproduce it, if you have an idea how to solve it, -- just do it, too !

(noone will get "assigned" to do it.)

[aimbot6120]

I tried to reproduce this issue.

it also segfaults, if it used like

mappPyr = cv.reg_MapperPyramid(cv.reg_MapperGradShift())

I could reproduce this on my machine (4.6.0 on Ubuntu 22.04 LTS)

I stack tra

ced this using gdb and got this

0x00007fffde14030c in ?? () from /home/<user>/.local/lib/python3.10/site-packages/cv2/cv2.abi3.so
I am not sure what to do with this info. any pointers on what source is involved in building cv2.abi3.so would be helpful.

I could not reproduce the "replacing dots with underscores" issue.

[VARUN-009]

I wanna work on this issue. Please assign this to me and since I'm new to this repo so I request you to please guide me through.

[aadarshahebsingh]

I'd really like to work on this issue. Please assign me and help me to get familiar as I'm new to Open Source

[ANKIT0017]

is this fixed? if anyone could verify.