concerning the multiple cameras and so on, this was just my need and why i'm not using CCV but be sure that i have nothing against CCV, it could be very useful in lots of context :-)
regarding driver, as i remember, i had issue with IIDC cameras but this was few years ago and by "cheap" i refer to some video digitizer with several inputs that make pd crashing on ubuntu but i think this is a V4L2 bug, not a pd's one cheers a -- do it yourself http://antoine.villeret.free.fr 2013/4/18 John Harrison <john.harri...@alum.mit.edu> > OK I guess I misunderstood that the original poster was wanting to do all > of that. I know the latest CCV supports multiple cameras for some sort of > "big picture" so it may actually do what you are asking but I don't know > the details so if you say it doesn't support all of that I'll go with your > claim. I'm sure the OpenCV solutions are great and perhaps in the future > I'll need to learn more about them as my own needs warrant. > > I haven't had a problem with the drivers on my "cheap" ps3eye V4L2 webcam > FWIW. I've also done tracking at 120-125fps 320x240 with 3 said webcams and > "buggy" drivers, all running simultaneously on one machine. No problems. > > John > > > On Thu, Apr 18, 2013 at 9:23 AM, Antoine Villeret < > antoine.ville...@gmail.com> wrote: > >> how is it possible to use several cameras, correct perspective on each, >> make a big picture with blending and then tracking on that big picture with >> CCV ? >> this have been done with Pd and pix_opencv and works great (at least if >> you're not using a cheap V4L2 cam with buggy drivers) >> >> -- >> do it yourself >> http://antoine.villeret.free.fr >> >> >> 2013/4/18 John Harrison <john.harri...@alum.mit.edu> >> >>> FWIW I had just the opposite experience with CCV. CCV has built-in >>> background adaptive subtraction, smoothing, highpass filter, gain, >>> contrast, etc. all tweakable. It also tracks blobs uniquely as the original >>> poster is wanting, which is why I thought of it for their needs. I used >>> [pix_blobtracker] before and it works OK but I found CCV to be overall a >>> more robust solution than anything I could efficiently come up with. >>> >>> I use CCV at 60fps 640x480 w/ a ps3eye on ubuntu 10.04 64 bit and the >>> CPU load is not significant and reduced from my original Pd-only solution. >>> My CCV/Pd patch has been on exhibit 24/7 for 5 months now without issue so >>> it also seems stable. I use CCV version 1.4. I also used CCV on another >>> exhibit with a Win7 64 bit system and that ran for months as well without >>> issue. That might have been version 1.5 but I don't remember for sure. I >>> also know there's a newer version of CCV supporting multiple cameras now, >>> and I have not had experience with this. >>> >>> Maybe I'm not understanding the flexibility you are looking for that CCV >>> is not offering you. All I can imagine is that you can't find a way to >>> change the order of the filtering. I'm not sure that's something you'll >>> find you actually need though to improve the result of the blob tracking. >>> >>> Just my $.02. >>> >>> -John >>> >>> On Thu, Apr 18, 2013 at 8:42 AM, Antoine Villeret < >>> antoine.ville...@gmail.com> wrote: >>> >>>> i tried CCV one time but i had some driver and performance issues >>>> moreover, i can't find an easy way to tune the processing chain >>>> pd is more flexible but, i agree, could be harder >>>> >>>> -- >>>> do it yourself >>>> http://antoine.villeret.free.fr >>>> >>>> >>>> 2013/4/18 John Harrison <john.harri...@alum.mit.edu> >>>> >>>>> I'm not totally clear on the big picture here but it could be you >>>>> might save yourself a lot of time and effort doing your blob tracking with >>>>> Community Core Vision (CCV) then sending the blob data to Pd through OSC. >>>>> After initially doing my blob tracking in Pd only (which did work), I >>>>> switched to this CCV --> Pd approach and got better results because of all >>>>> of the built-in filtering etc. that is provided with that open-source >>>>> cross-platform software. >>>>> >>>>> -John >>>>> >>>>> >>>>> On Thu, Apr 18, 2013 at 5:22 AM, Ska Frenz <skafr...@gmail.com> wrote: >>>>> >>>>>> Hi, thank you for the suggestions, I'll check openCv. Can you explain >>>>>> how to use "morphological filters" to clear up the noise in the image? >>>>>> Are >>>>>> there examples around? Also, could you please explain me better what do >>>>>> you >>>>>> mean with "adaptive background subtraction method"? >>>>>> >>>>>> Thank you for your time :) >>>>>> >>>>>> francesco >>>>>> >>>>>> >>>>>> 2013/4/17 Antoine Villeret <antoine.ville...@gmail.com> >>>>>> >>>>>>> hi, >>>>>>> >>>>>>> the segmentation method (how you extract what is your interest from >>>>>>> the rest of the image) is very critical in video tracking >>>>>>> background subtraction is a basic way to extract blob and it works >>>>>>> only in certain conditions of light (if you want to track something >>>>>>> outdoor, you should use an adaptive background subtraction method) >>>>>>> moreover, there is no general method to do video tracking, it >>>>>>> depends on what you want to track and how it is filmed >>>>>>> >>>>>>> so, the first thing is to have a good image, with not too much >>>>>>> lighting changes, good contrast between background and features to track >>>>>>> then you can start thinking about segmentation, and the >>>>>>> segmentation accuracy depends on the quality of the video >>>>>>> you may need to do something more than just background subtraction, >>>>>>> for example, you could apply some morphological filter to remove noise >>>>>>> after that, you can start tracking >>>>>>> you could also apply a threshold on the blob size to not track very >>>>>>> small blob >>>>>>> blob of interest are often surrounded by very small blobs due to >>>>>>> segmentation noise >>>>>>> >>>>>>> but you can have a look at pix_opencv objects, >>>>>>> there is [pix_opencv_blobtrack] which implements a whole processing >>>>>>> chain, including foreground extractor, blob detector, blob tracker and >>>>>>> follower >>>>>>> I'm not sure it's included in pd-extended, but you can find some >>>>>>> binaries on build server >>>>>>> >>>>>>> hope this help >>>>>>> >>>>>>> antoine >>>>>>> >>>>>>> >>>>>>> -- >>>>>>> do it yourself >>>>>>> http://antoine.villeret.free.fr >>>>>>> >>>>>>> >>>>>>> 2013/4/17 Ska Frenz <skafr...@gmail.com> >>>>>>> >>>>>>>> Hi everyone, this is my first time on the pd-list so I hope I >>>>>>>> won't do anything wrong. >>>>>>>> I'm writing here to get some help about pd tracking objects >>>>>>>> (pix_blob..). I'm using the background subtraction method, to track >>>>>>>> objects >>>>>>>> and I need help to understand how I can track multiple objects with >>>>>>>> multiples different blobs. I'm trying the pix_multiblob and yes, it >>>>>>>> show 2 >>>>>>>> blobs..but they track the same object. Then basically I do not >>>>>>>> understand >>>>>>>> how can I make the first blob to follow just one object for all the >>>>>>>> time >>>>>>>> that specific object is inside the webcam rectangle, and the second >>>>>>>> blob to >>>>>>>> track another separate object. I cannot find any material that clearly >>>>>>>> talks about this.I attached the patch I'm working on. I'd love to see >>>>>>>> some >>>>>>>> well-explained examples if you know where to get them. >>>>>>>> Thank you very much for your help :) >>>>>>>> >>>>>>>> Francesco >>>>>>>> >>>>>>>> _______________________________________________ >>>>>>>> Pd-list@iem.at mailing list >>>>>>>> UNSUBSCRIBE and account-management -> >>>>>>>> http://lists.puredata.info/listinfo/pd-list >>>>>>>> >>>>>>>> >>>>>>> >>>>>> >>>>>> _______________________________________________ >>>>>> Pd-list@iem.at mailing list >>>>>> UNSUBSCRIBE and account-management -> >>>>>> http://lists.puredata.info/listinfo/pd-list >>>>>> >>>>>> >>>>> >>>> >>> >> >
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