Cannot change video size in a thread (Bug #1241)

Added by Pavel Gurevich over 13 years ago. Updated over 9 years ago.

Status:Open Start date:
Priority:Normal Due date:
Assignee:Pavel Gurevich % Done:

0%
Category:highgui-camera
Target version:-
Affected version:branch '2.4' (2.4-dev) Operating System:Any
Difficulty: HW Platform:Any
Pull request:

Description

Changing resolution using

videoCapture -> set( CV_CAP_PROP_FRAME_WIDTH, width )

works fine in the main thread but has no effect inside a thread.

Associated revisions

Revision dc06d47f
Added by Roman Donchenko over 11 years ago

Merge pull request #1241 from SpecLad:redundant-precomps

Revision 122d0f86
Added by Roman Donchenko over 11 years ago

Deleted the now-empty ocl perf_precomp.cpp.

See pull request #1241 for why.

History

#1
Updated by Vadim Pisarevsky over 13 years ago

which OS do you use and what does CMake report in the summary section about video capturing?

#2
Updated by Alexander Shishkov almost 13 years ago

  • Priority changed from High to Normal
  • Target version deleted ()

#3
Updated by Andrey Kamaev almost 13 years ago

  • Category changed from imgproc, video to highgui-images

#4
Updated by Alexander Shishkov almost 13 years ago

  • Priority changed from Normal to Low

#5
Updated by Alexander Shishkov almost 13 years ago

  • Assignee deleted (Vadim Pisarevsky)

#6
Updated by Pavel Gurevich almost 13 years ago

I managed to made this work. The problem is that by default (as of 2.3.1) in the file cap_dshow.cpp which has a copy of videoinput library, the following define is commented out:

//if you need VI to use multi threaded com
#define VI_COM_MULTI_THREADED

Setting it will fix the issue. This is obviously a compile-time decision, and there is no build-time option for this. So, the question is if the current default is a good one.

#7
Updated by Alexander Shishkov almost 13 years ago

  • Tracker changed from Bug to Patch
  • Priority changed from Low to Normal

#8
Updated by Alexander Reshetnikov almost 13 years ago

  • Assignee set to Vadim Pisarevsky

#9
Updated by Alexander Shishkov almost 13 years ago

  • Target version deleted ()

#10
Updated by Pavel Gurevich over 12 years ago

As of 2.4.2, even the previous work-around stopped working. I saw much changes in the file cap_dshow.cpp, but meanwhile I cannot isolate the cause problem.

Meanwhile, I've noticed that the whole code section that initialized/deinitialized COM is commented out.

However, when I play with the values of tryWidth and tryHeight I do get the desired capture resolutions.

Currently seems like a degradation from the previous version (and the previous version of the file cannot be just dropped in because of the compilation problems).

#11
Updated by Andrey Kamaev over 12 years ago

  • Category changed from highgui-images to highgui-camera

#12
Updated by Kirill Kornyakov about 12 years ago

Pavel, could you please attach a repro code sample?

  • Affected version set to 2.4.2
  • Assignee changed from Vadim Pisarevsky to Pavel Gurevich

#13
Updated by Maksim Shabunin over 9 years ago

  • HW Platform set to Any
  • Operating System set to Any
  • Affected version changed from 2.4.2 to branch '2.4' (2.4-dev)

#14
Updated by Maksim Shabunin over 9 years ago

  • Tracker changed from Patch to Bug

#15
Updated by Maksim Shabunin over 9 years ago

Issue has been transferred to GitHub: https://github.com/Itseez/opencv/issues/4290

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