simple code for image coordinate to screen coordinate.

Arslan Ahmed, this is the post for you. ^^

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mouse event, setMouseCallback, opencv, Total,


AMP dose run on my pc?, AMP(Accelerated Massive Parallelism)

AMP is abbreviation of Accelerated Massive Parallelism.
It is maintained by Microsoft and it run based on DirectX 11.
So as I know, AMP works in windows only, but there seems to be an attempt to run on other os.

Basically, AMP run on these environment
  • Windows 7, Windows 8, Windows Server 2008 R2, or Windows Server 2012 
  • DirectX 11 Feature Level 11.0 or later hardware 
  • For debugging on the software emulator, Windows 8 or Windows Server 2012 is required. For debugging on the hardware, you must install the drivers for your graphics card.
And no need to install for AMP, If you use Visual Studio.
So let's check your computer condition for parallel programming.

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This is my condition.

We can check whether run or not by this.

if, accs.size() == 0, then there is no parallel machine.

I think AMP is easy and usefull to use parallel GPU programming.
This is useful for creating Windows applications.

reference site

Korean blog

MS site

MSDN AMP toturial


what is dp parameter in Hough Circle detection on opencv.

dp parameter is about resolution of voting space.
dp is larger, voting resolution is small compare to image size.
so dp is larger, circle detection accuracy is not exact.
but dp is smaller, voting resolution is higher and circle detection is more accurate but that sensitive with noise ex)other edge..
I increase dp from 1 to 5 step by 0.1..

refer to this source code on here.

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and result image.


and other reference.
opencv org

stack overflow

python opencv tutorial

GaussianBlur, HoughCircles, CV_HOUGH_GRADIENT,


Refer to this setting when you build opencv with TBB

When you build opencv with checking with_tbb option, cmake ask crrect paths about tbb.

Refer to this setting.
note, this is set for vc12 and 32bit.






TBB doesn't have CMakelist.txt, go to here.

Intel Threading Building Blocks..

I downloaded the source code here -> https://www.threadingbuildingblocks.org/
and I want to build it with cmake.

But I meet this error -> ...does not appear to contain CMakeLists.txt

Looking for a long time to figure out what to do ..
I found this site -> https://github.com/wjakob/tbb

Thank you.