<div dir="ltr">hi, <div><br></div><div style>the segmentation method (how you extract what is your interest from the rest of the image) is very critical in video tracking</div><div style>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)</div>
<div style>moreover, there is no general method to do video tracking, it depends on what you want to track and how it is filmed</div><div style><br></div><div style>so, the first thing is to have a good image, with not too much lighting changes, good contrast between background and features to track</div>
<div style>then you can start thinking about segmentation, and the segmentation accuracy depends on the quality of the video</div><div style>you may need to do something more than just background subtraction, for example, you could apply some morphological filter to remove noise</div>
<div style>after that, you can start tracking<br></div><div style>you could also apply a threshold on the blob size to not track very small blob</div><div style>blob of interest are often surrounded by very small blobs due to segmentation noise</div>
<div style><br></div><div style>but you can have a look at pix_opencv objects,</div><div style>there is [pix_opencv_blobtrack] which implements a whole processing chain, including foreground extractor, blob detector, blob tracker and follower</div>
<div style>I'm not sure it's included in pd-extended, but you can find some binaries on build server</div><div style><br></div><div style>hope this help</div><div style><br></div><div style>antoine</div><div style>
<br></div></div><div class="gmail_extra"><br clear="all"><div>--<br>do it yourself <br><a href="http://antoine.villeret.free.fr" target="_blank">http://antoine.villeret.free.fr</a><br></div>
<br><br><div class="gmail_quote">2013/4/17 Ska Frenz <span dir="ltr"><<a href="mailto:skafrenz@gmail.com" target="_blank">skafrenz@gmail.com</a>></span><br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
<div dir="ltr"><div><div><div>Hi everyone, this is my first time on the pd-list so I hope I won't do anything wrong. <br></div>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.<br>
</div>Thank you very much for your help :)<br><br></div>Francesco</div>
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