I hacked together this basic script to detect faces in images using OpenCV, Python, Web.py and ImageMagick. It’s a fun wee learning experience.
At the moment it tries to replace a face with an image. Some more tweaking, and it should be good to go. 
To run it:
import web, sys, os, subprocess, uuid
from opencv.cv import *
from opencv.highgui import *
from shutil import copy
def detectObjects(image, imagefile):
"""Converts an image to grayscale and prints the locations of any
faces found"""
grayscale = cvCreateImage(cvSize(image.width, image.height), 8, 1)
cvCvtColor(image, grayscale, CV_BGR2GRAY)
storage = cvCreateMemStorage(0)
cvClearMemStorage(storage)
cvEqualizeHist(grayscale, grayscale)
cascade = cvLoadHaarClassifierCascade(
'/usr/share/doc/opencv-doc/examples/haarcascades/haarcascades/haarcascade_frontalface_default.xml.gz',
cvSize(1,1))
faces = cvHaarDetectObjects(grayscale, cascade, storage, 1.2, 2,
CV_HAAR_DO_CANNY_PRUNING, cvSize(50,50))
if faces.total > 0:
for f in faces:
print("found a face: [(%d,%d) -> (%d,%d)]" % (f.x, f.y, f.x+f.width, f.y+f.height))
foundFace(imagefile, f)
return faces.total
def foundFace(imagefile, f):
#os.system("convert {image} -stroke red -fill red -draw \"rectangle {a},{b} {c},{d}\" {output}".format(
os.system("convert {image} -draw \"image SrcOver {a},{b} {c},{d} biglazer.png\" {output}".format(
image=imagefile,
a=f.x+6,
b=f.y,
c=f.width,
d=f.height,
output=imagefile));
urls = (
'/upload', 'Upload',
)
class Upload:
def GET(self):
web.header("Content-Type","text/html; charset=utf-8")
return """<html><head><link rel="shortcut icon" href="/static/favicon.ico"
type="image/x-icon"></head><body>
<form method="POST" enctype="multipart/form-data" action="">
<input type="file" name="myfile" />
<br/>
<input type="submit" />
</form>
</body></html>"""
def POST(self):
x = web.input(myfile={})
filedir = '/home/mike/python/uploads' # change this to the directory you want to store the file in.
if 'myfile' in x: # to check if the file-object is created
filepath=x.myfile.filename.replace('\\','/') # replaces the windows-style slashes with linux ones.
#filename=filepath.split('/')[-1] # splits the and chooses the last part (the filename with extension)
filename = str(uuid.uuid4())
fout = open(filedir +'/'+ filename,'w') # creates the file where the uploaded file should be stored
fout.write(x.myfile.file.read()) # writes the uploaded file to the newly created file.
fout.close() # closes the file, upload complete.
# detect face
imagefile = filedir +'/'+ filename;
image = cvLoadImage(imagefile);
unique_name = str(uuid.uuid4())
output_path = '/home/mike/python/static/%s.png' % unique_name
if (detectObjects(image, imagefile) > 0):
copy(imagefile, output_path)
web.redirect("static/%s.png" % unique_name)
else:
return """No face found."""
raise web.seeother('/upload')
if __name__ == "__main__":
app = web.application(urls, globals(), True)
app.run()
There are some problems – it doesn’t like bitmap (*.BMP) nor cartoon type images. Here are some examples of images that worked:
Tags: detect, face, face detect, image, imagemagick, opencv, Python, upload image, web.py
