--- /dev/null
+#!/usr/bin/python
+from opencv.cv import *
+from opencv.highgui import *
+import sys
+import time
+from math import cos,sin
+
+CLOCKS_PER_SEC = 1.0
+MHI_DURATION = 1
+MAX_TIME_DELTA = 0.5
+MIN_TIME_DELTA = 0.05
+N = 4
+buf = range(10)
+last = 0
+mhi = None # MHI
+orient = None # orientation
+mask = None # valid orientation mask
+segmask = None # motion segmentation map
+storage = None # temporary storage
+
+def update_mhi( img, dst, diff_threshold ):
+ global last
+ global mhi
+ global storage
+ global mask
+ global orient
+ global segmask
+ timestamp = time.clock()/CLOCKS_PER_SEC # get current time in seconds
+ size = cvSize(img.width,img.height) # get current frame size
+ idx1 = last
+ if not mhi or mhi.width != size.width or mhi.height != size.height:
+ for i in range( N ):
+ buf[i] = cvCreateImage( size, IPL_DEPTH_8U, 1 )
+ cvZero( buf[i] )
+ mhi = cvCreateImage( size, IPL_DEPTH_32F, 1 )
+ cvZero( mhi ) # clear MHI at the beginning
+ orient = cvCreateImage( size, IPL_DEPTH_32F, 1 )
+ segmask = cvCreateImage( size, IPL_DEPTH_32F, 1 )
+ mask = cvCreateImage( size, IPL_DEPTH_8U, 1 )
+
+ cvCvtColor( img, buf[last], CV_BGR2GRAY ) # convert frame to grayscale
+ idx2 = (last + 1) % N # index of (last - (N-1))th frame
+ last = idx2
+ silh = buf[idx2]
+ cvAbsDiff( buf[idx1], buf[idx2], silh ) # get difference between frames
+ cvThreshold( silh, silh, diff_threshold, 1, CV_THRESH_BINARY ) # and threshold it
+ cvUpdateMotionHistory( silh, mhi, timestamp, MHI_DURATION ) # update MHI
+ cvCvtScale( mhi, mask, 255./MHI_DURATION,
+ (MHI_DURATION - timestamp)*255./MHI_DURATION )
+ cvZero( dst )
+ cvMerge( mask, None, None, None, dst )
+ cvCalcMotionGradient( mhi, mask, orient, MAX_TIME_DELTA, MIN_TIME_DELTA, 3 )
+ if( not storage ):
+ storage = cvCreateMemStorage(0)
+ else:
+ cvClearMemStorage(storage)
+ seq = cvSegmentMotion( mhi, segmask, storage, timestamp, MAX_TIME_DELTA )
+ for i in range(-1, seq.total):
+ if( i < 0 ): # case of the whole image
+ comp_rect = cvRect( 0, 0, size.width, size.height )
+ color = CV_RGB(255,255,255)
+ magnitude = 100.
+ else: # i-th motion component
+ comp_rect = seq[i].rect
+ if( comp_rect.width + comp_rect.height < 100 ): # reject very small components
+ continue
+ color = CV_RGB(255,0,0)
+ magnitude = 30.
+ silh_roi = cvGetSubRect(silh, comp_rect)
+ mhi_roi = cvGetSubRect( mhi, comp_rect )
+ orient_roi = cvGetSubRect( orient, comp_rect )
+ mask_roi = cvGetSubRect( mask, comp_rect )
+ angle = cvCalcGlobalOrientation( orient_roi, mask_roi, mhi_roi, timestamp, MHI_DURATION)
+ angle = 360.0 - angle # adjust for images with top-left origin
+ count = cvNorm( silh_roi, None, CV_L1, None ) # calculate number of points within silhouette ROI
+ if( count < comp_rect.width * comp_rect.height * 0.05 ):
+ continue
+ center = cvPoint( (comp_rect.x + comp_rect.width/2),
+ (comp_rect.y + comp_rect.height/2) )
+ cvCircle( dst, center, cvRound(magnitude*1.2), color, 3, CV_AA, 0 )
+ cvLine( dst, center, cvPoint( cvRound( center.x + magnitude*cos(angle*CV_PI/180)),
+ cvRound( center.y - magnitude*sin(angle*CV_PI/180))), color, 3, CV_AA, 0 )
+
+if __name__ == "__main__":
+ motion = 0
+ capture = 0
+
+ if len(sys.argv)==1:
+ capture = cvCreateCameraCapture( 0 )
+ elif len(sys.argv)==2 and sys.argv[1].isdigit():
+ capture = cvCreateCameraCapture( int(sys.argv[1]) )
+ elif len(sys.argv)==2:
+ capture = cvCreateFileCapture( sys.argv[1] )
+
+ if not capture:
+ print "Could not initialize capturing..."
+ sys.exit(-1)
+
+ cvNamedWindow( "Motion", 1 )
+ while True:
+ image = cvQueryFrame( capture )
+ if( image ):
+ if( not motion ):
+ motion = cvCreateImage( cvSize(image.width,image.height), 8, 3 )
+ cvZero( motion )
+ #motion.origin = image.origin
+ update_mhi( image, motion, 30 )
+ cvShowImage( "Motion", motion )
+ if( cvWaitKey(10) != -1 ):
+ break
+ else:
+ break
+ cvDestroyWindow( "Motion" )