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Mostly for fun, I have concocted a way of acquiring video using Labview for linux, to mend for the unavailability of IMAQdx.

The idea is to grab via v4l2, actually through the handler libv4l2, and to display simply via the picture control.
I have tested this for the moment only with webcams at 640x480 on LV11 and 13 (both 32bits) on two different installations of Ubuntu 12.04 64bits, and it works. This means v4l-utils 0.8.6-1ubuntu2, 32bit.

Attached is a proof of the concept, essentially a translation of the Appendix E example to the linuxtv API, saved for LV11. I include also a loose set of tools I built myself in order to parse the relevant headers and construct semiautomatically the necessary typedefs (LV13, no backsave out of lazyness).

I have two questions:

-Is this insane enough to qualify for this forum, or do I have seriously seriously to exaggerate?

-Is someone interested in helping me to expand the exercise, checking portability on other distributions and versions of v4l2, other supported image formats, more robust packaging & so on? Intention would be to release a package under GPL.

Enrico

 


med_gallery_28229_99_301487.png

med_gallery_28229_99_33736.png

grab11.zip

Import_headers.zip

Edited by ensegre
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I can't answer the second question, since I don't use Linux or IMAQ (although I would suggest using a license other than GPL if possible, such as BSD), but I can answer the first question with "yes" - there are absolutely no restriction on which code you post here, as long as it's your own code. You can post tools, demos, ideas, experiments or just ask questions. Certainly any tool is welcome.

 

If you want to add the tool to the LAVA code repository or the LV tools network there are some rules you have to follow, and those are documented in the relevant places. I'm fairly sure that code insanity isn't one of those requirements, though ;) .

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Ah, the good old white stretch to the right of the FP menu bar.  Drives me nuts, I try to chalk it up to the cost of doing business on Ubuntu.

 

I'll download and check it out sometime.  I am curious how it compares to OpenCV.

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In a further verge of insanity, I've beefed it up with "high level grab oriented" subvis, cleaned up a little the grabber example, and submitted the whole to the uncertified repository. Hopefully formatting it right, my first submission.

 

@Darin: it doesn't really compare with OpenCV; this is only grabbing, while LV for linux doesn't have any image processing VI. OTOH I understand that within OpenCV you can grab via v4l too. However I don't know of any available LV-OpenCV glue besides Eran Herman's, which is commercial and for windows only AFAIK.

 

Screenshot from 2013 09 03 19:29:20
Screenshot from 2013 09 03 20:35:36
Edited by ensegre

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pinging in just to say that I tested that it works fine also in ubuntu 13.04, libv4l2-0-0.8.9.1, LV13.

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