OpenCV in WorldViz

[nige777]

Thanks you very much that worked perfectly.

Now I, like the original poster, just need to sort a method for converting frame buffer images to IPLImage!!

Came across this -

http://www.depthfirstsearch.net/blog...cv-and-python/

- which seems to address this prob however I am unable to utilize this at the moment due to my severe lack of C or C++ know-how. Any windows/C++ wizards out there who could help?

[sircedric4]

Originally Posted by nige777

Thanks you very much that worked perfectly.

Now I, like the original poster, just need to sort a method for converting frame buffer images to IPLImage!!

Came across this -

http://www.depthfirstsearch.net/blog...cv-and-python/

- which seems to address this prob however I am unable to utilize this at the moment due to my severe lack of C or C++ know-how. Any windows/C++ wizards out there who could help?

I am still trying to find a better way to do the conversion myself, but in the meantime I was able to get something to "work" using the actual screen capture and file save capability in Vizard.

I used the viztask schedule capability and basically saved each image to a bitmap and then loaded the bitmaps into the squares example. It is slow, only average 2 -3 frames per second which doesn't work for me, but might work for your application. I am attaching the code I used in squares for you to look at. Maybe it'll help you.

Like, you I found that same link that might address the problem but I couldn't figure out how to do anything with it. I do know C++, but only as a language. Getting all the plugins, modules, and runtime environments setup is beyond my capability. I'd kill for some sort of class to attend that would cover all the setup stuff that people assume you know just because you know a language.

def SquareIt():
	global img, storage

	while True:
		name = 'C:/DK Files/OpenCV Learn/test1.bmp'
		yield viz.window.screenCapture(name)
#
		# create memory storage that will contain all the dynamic data
		storage = cvCreateMemStorage(0);
		img0 = cvLoadImage( name, 1 );
		if not img0:
			print "Couldn't load %s" % name
		img = cvCloneImage( img0 );
		# force the image processing
		on_trackbar(0);
		# Also the function cvWaitKey takes care of event processing
		cvWaitKey(5);
			# clear memory storage - reset free space position
		cvClearMemStorage( storage );

t = viztask.schedule( SquareIt() )
vizact.onkeyup('s',t.kill)

[JimC]

Yes, figuring out how to build complex C/C++ projects is a hideous nightmare, particularly on Windows with its plethora of compilers. That's why sane people prefer Python.

You might have a look at ctypes_opencv. It's not intended for Python 2.4, but as it's pure python code it might be made to work. Requires the ctypes module, and there are quite a few lines of the form:

min_val_p = c_double() if min_val is True else min_val

that need to be converted to e.g.:

if min_val is True:
  min_val_p = c_double()
else:
  min_val_p = min_val

Those are the difficulties that appear right off the bat, anyway...

[JimC]

You might have a look at ctypes_opencv. It's not intended for Python 2.4, but as it's pure python code it might be made to work.

Sorry, that was perhaps not clear. It's still a wrapper around the C dlls, but ctypes allows you to write the wrapper directly in Python rather than in some C-like (SWIG) or C++-like (SIP) dialect...If the problem is in the original pyopencv wrapper code, then this might provide a workaround...

[JimC]

OK, I got interested and got it to work (at least, I got capture-cam and a couple others to run). Download. The src/ctypes_opencv folder goes in Vizard's site-packages directory, there's also a folder of modified demos (I assume the syntax is a bit different). Let me know if the PIL conversion works...

[nige777]

Wow, you really are the man . I'm itching to try this out - will report back as soon as I have.

[JimC]

I wrote to the author of ctypes-opencv and ended up applying the fixes to the bleeding-edge version and mailing that to him. Interestingly, it looked like there might be some code added to the bleeding-edge version relevant to exactly the problem you've been writing about, so you might want to look at that. It's here.