html5 - Camera object detection in JavaScript -

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suppose user has modern browser chrome , enables necessary html5 camera settings (so getusermedia works), how 1 detect specific predefined objects shown in webcam sight, using javascript?

for instance, there's html5/ js-based face detection works great, , saw hand detection demo (which didn't work here; might doing wrong). necessary steps train camera detect given other objects of (developer) choice? say, want cam recognize location of red pen; or perhaps darkest object in sight; or perhaps black iphone waved camera etc.

thanks!

object detection in tricky business. have know object is, whether smooth, flexible, has lot of color contrast, moves quickly, , lot of other questions before can determine best method.

also, depends on whether want detect object, or if want track it during movement in front of camera.

i'll naming few methods here, because don't have time elaborate lot. can find lot of documentation on google once know names, aware might need mathematical skills if have implement them yourself. so, involves :

  • computing descriptors @ interesting points. @ sift or hog (histograms of gradients) descriptors on google, these used ones.
  • building kind recognition structure, which, again, can change greatly, depending upon object , descriptors. popular methods include neural networks, support vector machines. moving objects, can add graph-related techniques such graph cuts mix.

again, depending on object, these might not close right method.

as far know, there's little software available in javascript, i'd happy know if find something. again, here few pointers :

  • your face detection sample using popular called cascade classifier, available in more popular library opencv, , considered the method of choice face detection.
  • if can consider moving part of processing server, use opencv has tons of available algorithms.

i hope able start little bit ;)


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