Re: [PD] pix_multiblob and tracking multiple objects

2013-04-18 Thread Ska Frenz
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

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Re: [PD] pix_multiblob and tracking multiple objects

2013-04-18 Thread John Harrison
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

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Re: [PD] pix_multiblob and tracking multiple objects

2013-04-18 Thread Antoine Villeret
morphological filters affect the shape
they mostly work on binary images
the most common are erode, dilate, close and open algorithm
with which you can make a pepper or salt removing filter to remove black
or white isolated pixels

concerning background subtraction, if you use a fixed background (you make
a snapshot at startup and subtract it to the video stream) you will have
defects due to light change,
some background part could be interpreted as a foreground feature
adaptive background technique use a dynamic image reference, which could be
made with a low-pass filter, this image is then subtracted to the video
stream
this makes a high-pass filter




--
do it yourself
http://antoine.villeret.free.fr


2013/4/18 Ska Frenz skafr...@gmail.com

 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

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Re: [PD] pix_multiblob and tracking multiple objects

2013-04-18 Thread Antoine Villeret
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

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Re: [PD] pix_multiblob and tracking multiple objects

2013-04-18 Thread John Harrison
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
 

Re: [PD] pix_multiblob and tracking multiple objects

2013-04-18 Thread Antoine Villeret
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 

Re: [PD] pix_multiblob and tracking multiple objects

2013-04-18 Thread John Harrison
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
 

Re: [PD] pix_multiblob and tracking multiple objects

2013-04-18 Thread Antoine Villeret
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 

[PD] pix_multiblob and tracking multiple objects

2013-04-17 Thread Ska Frenz
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


blob 1.pd
Description: Binary data
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Re: [PD] pix_multiblob and tracking multiple objects

2013-04-17 Thread Antoine Villeret
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

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Re: [PD] pix_multiblob and tracking multiple objects

2013-04-17 Thread IOhannes zmölnig

On 04/17/2013 09:59 PM, Ska Frenz wrote:

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 :)


checkout [pix_blobtracker] for a rudimentary labelling algorithm using 
[pix_multiblob].


gfmasdr
IOhannes

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