c++ - Region of Interest Uniqueness and Identity -


i'm working computer vision application opencv. application involves target identification , characteristic determination. generally, i'm going have target cross visible region , move through in couple of seconds. should give me upwards of 50-60 frames camera in i'll able find target.

we have implemented detection algorithms using swt , ocr (the targets have alphanumeric identifiers, makes them relatively easy pick out). want use of data possible 50-60 shots of each target. this, need way identify particular roi of image 2 contains same target roi image 1.

what i'm asking little advice may have come across before. how can easily/quickly identify, within reasonable error margin, roi #2 has same target roi#1? first instinct this:

  1. detect targets in frame 1.
  2. calculate unique features of each of targets in frame 1. save.
  3. get frame 2.
  4. immediately rois have same features calc'd in step 2. grab these , send them down line further processing, skipping step 5.
  5. detect new targets in frame 2.
  6. pass targets thread calculate shape, color, gps coordinates, etc.
  7. lather, rinse, repeat.

i'm thinking surf or sift features might way accomplish this, i'm concerned might have trouble identifying targets same frame frame due distortion or color fade. don't know how set threshold on sift/surf features.

thank in advance light can shed on matter.

one thing can locally equalize brightness , possibly saturation levels. if aren't using advanced space such ycrcb or hsv, suggest try them.

can assume object not moving fast? if feed previous position in detection routine, can decrease size of window looking at. same thing goes speed, , direction of movement.

i've used histogram composition , shape descriptors of region in order reliably detect it, can use or add surf/sift classifier.


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