video - Analyzing camera feed under OSX -

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i looking way programmatically analyze video feed external usb webcam under osx.

since haven't done low level programming before kind of lost on start.

how can access webcam feed , grab image data process further? @ point trying understand basic concept , not looking language-specific solutions. sample code highly appreciated.

i'd appreciate if point me in right direction , me started.

thank in advance!

thomas

use opencv.

and check previous answer on subject if looking code example display webcam images. converts video feed grayscale , displays them on window:

opencv 2.1: runtime error

if want display frames, replace else block this:

else {     cvshowimage("colored video", color_frame); }

in case wandering how manipulate pixels of frame:

int width = color_frame->width;  int height = color_frame->height; int bpp = color_frame->nchannels;  (int i=0; < width*height*bpp; i+=bpp)  {   if (!(i % (width*bpp))) // print empty line better readability       std::cout << std::endl;    std::cout << std::dec << "r:" << (int) color_frame->imagedata[i] <<                             " g:" << (int) color_frame->imagedata[i+1] <<                             " b:" << (int) color_frame->imagedata[i+2] << " ";  }

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