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Finding coordinates of face in Python

I am trying to send the coordinates of a face found with opencv over serial. I got the serial part downpath but I can't figure out how to find the coordinates of the face. I would like to if possible use the facedetection.py example as the base... Any ideas? Thanks ahead of time!

Finding coordinates of face in PythonPython[Updated]

I am trying to send the coordinates of a face found with opencv over serial. I got the serial part downpath but I can't figure out how to find the coordinates of the face. I would like to if possible use the facedetection.py example as the base... Any ideas? Thanks ahead of time!time! Here is the facedetect.py code:

!/usr/bin/env python

import numpy as np import cv2

local modules

from video import create_capture from common import clock, draw_str

help_message = ''' USAGE: facedetect.py [--cascade <cascade_fn>] [--nested-cascade <cascade_fn>] [<video_source>] '''

def detect(img, cascade): rects = cascade.detectMultiScale(img, scaleFactor=1.3, minNeighbors=4, minSize=(30, 30), flags = cv2.CASCADE_SCALE_IMAGE) if len(rects) == 0: return [] rects[:,2:] += rects[:,:2] return rects

def draw_rects(img, rects, color): for x1, y1, x2, y2 in rects: cv2.rectangle(img, (x1, y1), (x2, y2), color, 2)

if __name__ == '__main__': import sys, getopt print help_message

args, video_src = getopt.getopt(sys.argv[1:], '', ['cascade=', 'nested-cascade='])
try:
    video_src = video_src[0]
except:
    video_src = 0
args = dict(args)
cascade_fn = args.get('--cascade', "../../data/haarcascades/haarcascade_frontalface_alt.xml")
nested_fn  = args.get('--nested-cascade', "../../data/haarcascades/haarcascade_eye.xml")

cascade = cv2.CascadeClassifier(cascade_fn)
nested = cv2.CascadeClassifier(nested_fn)

cam = create_capture(video_src, fallback='synth:bg=../cpp/lena.jpg:noise=0.05')

while True:
    ret, img = cam.read()
    gray = cv2.cvtColor(img, cv2.COLOR_BGR2GRAY)
    gray = cv2.equalizeHist(gray)

    t = clock()
    rects = detect(gray, cascade)
    vis = img.copy()
    draw_rects(vis, rects, (0, 255, 0))
    for x1, y1, x2, y2 in rects:
        roi = gray[y1:y2, x1:x2]
        vis_roi = vis[y1:y2, x1:x2]
        subrects = detect(roi.copy(), nested)
        draw_rects(vis_roi, subrects, (255, 0, 0))
    dt = clock() - t

    draw_str(vis, (20, 20), 'time: %.1f ms' % (dt*1000))
    cv2.imshow('facedetect', vis)

    if 0xFF & cv2.waitKey(5) == 27:
        break
cv2.destroyAllWindows()

Sorry about the formatting... Thanks for all the help so far!

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No.3 Revision

updated 2014-11-06 12:15:39 -0500

berak gravatar image

Finding coordinates of face in Python[Updated]

I am trying to send the coordinates of a face found with opencv over serial. I got the serial part downpath but I can't figure out how to find the coordinates of the face. I would like to if possible use the facedetection.py example as the base... Any ideas? Thanks ahead of time! Here is the facedetect.py code:

!/usr/bin/env python

#!/usr/bin/env python

import numpy as np
import cv2

cv2 # local modules

modules from video import create_capture from common import clock, draw_str

draw_str help_message = ''' USAGE: facedetect.py [--cascade <cascade_fn>] [--nested-cascade <cascade_fn>] [<video_source>] '''

''' def detect(img, cascade): rects = cascade.detectMultiScale(img, scaleFactor=1.3, minNeighbors=4, minSize=(30, 30), flags = cv2.CASCADE_SCALE_IMAGE) if len(rects) == 0: return [] rects[:,2:] += rects[:,:2] return rects

rects def draw_rects(img, rects, color): for x1, y1, x2, y2 in rects: cv2.rectangle(img, (x1, y1), (x2, y2), color, 2)

2) if __name__ == '__main__': import sys, getopt print help_message

help_message

    args, video_src = getopt.getopt(sys.argv[1:], '', ['cascade=', 'nested-cascade='])
 try:
     video_src = video_src[0]
 except:
     video_src = 0
 args = dict(args)
 cascade_fn = args.get('--cascade', "../../data/haarcascades/haarcascade_frontalface_alt.xml")
 nested_fn  = args.get('--nested-cascade', "../../data/haarcascades/haarcascade_eye.xml")

 cascade = cv2.CascadeClassifier(cascade_fn)
 nested = cv2.CascadeClassifier(nested_fn)

 cam = create_capture(video_src, fallback='synth:bg=../cpp/lena.jpg:noise=0.05')

 while True:
     ret, img = cam.read()
     gray = cv2.cvtColor(img, cv2.COLOR_BGR2GRAY)
     gray = cv2.equalizeHist(gray)

     t = clock()
     rects = detect(gray, cascade)
     vis = img.copy()
     draw_rects(vis, rects, (0, 255, 0))
     for x1, y1, x2, y2 in rects:
         roi = gray[y1:y2, x1:x2]
         vis_roi = vis[y1:y2, x1:x2]
         subrects = detect(roi.copy(), nested)
         draw_rects(vis_roi, subrects, (255, 0, 0))
     dt = clock() - t

     draw_str(vis, (20, 20), 'time: %.1f ms' % (dt*1000))
     cv2.imshow('facedetect', vis)

     if 0xFF & cv2.waitKey(5) == 27:
         break
 cv2.destroyAllWindows()

Sorry about the formatting... Thanks for all the help so far!