5. OpenCV Tutorial - Learn Classic Computer Vision & Face Detection (OPTIONAL)/32. Blob Detection - Detect The Center of Flowers.srt

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OK so let's talk about blubbed detection so blood production songs but where.

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However if you've been into Computer Vision world for some time you would have bound to come across

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it by now.

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So what exactly is a blob.

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Well a blob just like a real life blob.

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I guess it's just a group of connected pixels that share similar property.

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So in this example of the sunflowers here you can see the sense of flowers some flowers all have similar

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green tinge here.

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That's basically what blubbed ejection has picked up now no properties can be size it can be shape and

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we actually get to that shortly.

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So in general how do we use open of his simple blood test.

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That's demitted what we call in Bigham.

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So what do we do first we create or initialize the detector object we input an image into detector.

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We then optin the key points and then we draw those key points like we do here.

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So let's actually get into the code and do this.

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OK.

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So let's open a simple blob detector file here selects you for point it.

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So here's a code for it here.

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Doesn't look too scary.

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It's pretty basic actually.

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So let's run this could see what's happening here.

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So we've loaded up a great skill image of sunflowers that you saw previously and we've identified blobs

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in the center of the fellows here.

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Quite nice.

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So let's see how we do this.

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So first if we RIDO imagen and previously.

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So if I just putting a zero here we can actually call grayscale image.

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I mean at a critical image in here.

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However this is zero actually signifies you're writing in this line of function here so you may have

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seen some open Sivy functions where we have numbers instead of the actual words here.

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That's just shorthand

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so I'm moving on.

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So the first part of this here is that we need to initialize the doctor.

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So we call this function here.

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Well this class actually and we create to detect the object and using this object now we actually pass.

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We run the detect method within this object here.

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We pass the image the input image into it here and this gives us several key points key points being

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all blubs detected.

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So it is no tuning of parameters here.

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What is some tuning up from now is basically here where we draw the key points and image.

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Now however these parameters don't affect the number of blobs that were identified they just affect

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how would a ball blubbers looked like on the image itself.

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So this is pretty self-explanatory here.

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In that image the key points we identified so blank actually here as well as open Zeevi type Quick's.

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It's just a one by one matrix of zeroes here.

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So pretty much ignore it and just use this going forward.

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This here's a color which we use yellow is green and red here and this is how we draw the points here.

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So it actually just changed this just now to reach key points.

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We can see it's actually yellow now.

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However Initially we used the default one which I believe was this dude.

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The fold there just looks a bit smaller.

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So it is no big difference.

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OK.

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So let's move on to it.

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Too many projects where we actually filter different types of blobs because as you saw here in simple

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blood detect and detect there's no problem to here.

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Well actually there is.

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We'll get to it shortly.