python: 'cv2.' -> 'cv.' via 'import cv2 as cv'

modules/bgsegm/samples/evaluation.py

 import argparse
-import cv2
+import cv2 as cv
 import glob
 import numpy as np
 import os
@@ -12,15 +12,15 @@ import time
 
 
 ALGORITHMS_TO_EVALUATE = [
-    (cv2.bgsegm.createBackgroundSubtractorMOG, 'MOG', {}),
-    (cv2.bgsegm.createBackgroundSubtractorGMG, 'GMG', {}),
-    (cv2.bgsegm.createBackgroundSubtractorCNT, 'CNT', {}),
-    (cv2.bgsegm.createBackgroundSubtractorLSBP, 'LSBP-vanilla', {'nSamples': 20, 'LSBPRadius': 4, 'Tlower': 2.0, 'Tupper': 200.0, 'Tinc': 1.0, 'Tdec': 0.05, 'Rscale': 5.0, 'Rincdec': 0.05, 'LSBPthreshold': 8}),
-    (cv2.bgsegm.createBackgroundSubtractorLSBP, 'LSBP-speed', {'nSamples': 10, 'LSBPRadius': 16, 'Tlower': 2.0, 'Tupper': 32.0, 'Tinc': 1.0, 'Tdec': 0.05, 'Rscale': 10.0, 'Rincdec': 0.005, 'LSBPthreshold': 8}),
-    (cv2.bgsegm.createBackgroundSubtractorLSBP, 'LSBP-quality', {'nSamples': 20, 'LSBPRadius': 16, 'Tlower': 2.0, 'Tupper': 32.0, 'Tinc': 1.0, 'Tdec': 0.05, 'Rscale': 10.0, 'Rincdec': 0.005, 'LSBPthreshold': 8}),
-    (cv2.bgsegm.createBackgroundSubtractorLSBP, 'LSBP-camera-motion-compensation', {'mc': 1}),
-    (cv2.bgsegm.createBackgroundSubtractorGSOC, 'GSOC', {}),
-    (cv2.bgsegm.createBackgroundSubtractorGSOC, 'GSOC-camera-motion-compensation', {'mc': 1})
+    (cv.bgsegm.createBackgroundSubtractorMOG, 'MOG', {}),
+    (cv.bgsegm.createBackgroundSubtractorGMG, 'GMG', {}),
+    (cv.bgsegm.createBackgroundSubtractorCNT, 'CNT', {}),
+    (cv.bgsegm.createBackgroundSubtractorLSBP, 'LSBP-vanilla', {'nSamples': 20, 'LSBPRadius': 4, 'Tlower': 2.0, 'Tupper': 200.0, 'Tinc': 1.0, 'Tdec': 0.05, 'Rscale': 5.0, 'Rincdec': 0.05, 'LSBPthreshold': 8}),
+    (cv.bgsegm.createBackgroundSubtractorLSBP, 'LSBP-speed', {'nSamples': 10, 'LSBPRadius': 16, 'Tlower': 2.0, 'Tupper': 32.0, 'Tinc': 1.0, 'Tdec': 0.05, 'Rscale': 10.0, 'Rincdec': 0.005, 'LSBPthreshold': 8}),
+    (cv.bgsegm.createBackgroundSubtractorLSBP, 'LSBP-quality', {'nSamples': 20, 'LSBPRadius': 16, 'Tlower': 2.0, 'Tupper': 32.0, 'Tinc': 1.0, 'Tdec': 0.05, 'Rscale': 10.0, 'Rincdec': 0.005, 'LSBPthreshold': 8}),
+    (cv.bgsegm.createBackgroundSubtractorLSBP, 'LSBP-camera-motion-compensation', {'mc': 1}),
+    (cv.bgsegm.createBackgroundSubtractorGSOC, 'GSOC', {}),
+    (cv.bgsegm.createBackgroundSubtractorGSOC, 'GSOC-camera-motion-compensation', {'mc': 1})
 ]
 
 
@@ -54,14 +54,14 @@ def evaluate_algorithm(gt, frames, algo, algo_arguments):
     t_start = time.time()
 
     for i in range(len(gt)):
-        frame = np.uint8(cv2.imread(frames[i], cv2.IMREAD_COLOR))
+        frame = np.uint8(cv.imread(frames[i], cv.IMREAD_COLOR))
         mask.append(bgs.apply(frame))
 
     average_duration = (time.time() - t_start) / len(gt)
     average_precision, average_recall, average_f1, average_accuracy = [], [], [], []
 
     for i in range(len(gt)):
-        gt_mask = np.uint8(cv2.imread(gt[i], cv2.IMREAD_GRAYSCALE))
+        gt_mask = np.uint8(cv.imread(gt[i], cv.IMREAD_GRAYSCALE))
         roi = ((gt_mask == 255) | (gt_mask == 0))
         if roi.sum() > 0:
             gt_answer, answer = gt_mask[roi], mask[i][roi]

modules/bgsegm/samples/viz.py

 import numpy as np
-import cv2
+import cv2 as cv
 import argparse
 import os
 
@@ -17,22 +17,22 @@ def main():
     f = map(lambda x: os.path.join(args.frames, x), os.listdir(args.frames))
     f.sort()
 
-    gt = np.uint8(map(lambda x: cv2.imread(x, cv2.IMREAD_GRAYSCALE), gt))
-    f = np.uint8(map(lambda x: cv2.imread(x, cv2.IMREAD_COLOR), f))
+    gt = np.uint8(map(lambda x: cv.imread(x, cv.IMREAD_GRAYSCALE), gt))
+    f = np.uint8(map(lambda x: cv.imread(x, cv.IMREAD_COLOR), f))
 
     if not args.lsbp:
-        bgs = cv2.bgsegm.createBackgroundSubtractorGSOC()
+        bgs = cv.bgsegm.createBackgroundSubtractorGSOC()
     else:
-        bgs = cv2.bgsegm.createBackgroundSubtractorLSBP()
+        bgs = cv.bgsegm.createBackgroundSubtractorLSBP()
 
     for i in xrange(f.shape[0]):
-        cv2.imshow('Frame', f[i])
-        cv2.imshow('Ground-truth', gt[i])
+        cv.imshow('Frame', f[i])
+        cv.imshow('Ground-truth', gt[i])
         mask = bgs.apply(f[i])
         bg = bgs.getBackgroundImage()
-        cv2.imshow('BG', bg)
-        cv2.imshow('Output mask', mask)
-        k = cv2.waitKey(0)
+        cv.imshow('BG', bg)
+        cv.imshow('Output mask', mask)
+        k = cv.waitKey(0)
         if k == 27:
             break
 

modules/bgsegm/samples/viz_synthetic_seq.py

-import cv2
+import cv2 as cv
 import argparse
 
 
@@ -9,15 +9,15 @@ def main():
     argparser.add_argument('-o', '--obj', help='Object image. It must be strictly smaller than background.', required=True)
     args = argparser.parse_args()
 
-    bg = cv2.imread(args.background)
-    obj = cv2.imread(args.obj)
-    generator = cv2.bgsegm.createSyntheticSequenceGenerator(bg, obj)
+    bg = cv.imread(args.background)
+    obj = cv.imread(args.obj)
+    generator = cv.bgsegm.createSyntheticSequenceGenerator(bg, obj)
 
     while True:
         frame, mask = generator.getNextFrame()
-        cv2.imshow('Generated frame', frame)
-        cv2.imshow('Generated mask', mask)
-        k = cv2.waitKey(int(1000.0 / 30))
+        cv.imshow('Generated frame', frame)
+        cv.imshow('Generated mask', mask)
+        k = cv.waitKey(int(1000.0 / 30))
         if k == 27:
             break
 

modules/bioinspired/doc/retina.markdown

@@ -4,7 +4,7 @@ Bioinspired Module Retina Introduction {#bioinspired_retina}
 Retina class overview
 ---------------------
 
-@note do not forget that the retina model is included in the following namespace : cv::bioinspired with C++ and in cv2.bioinspired with Python
+@note do not forget that the retina model is included in the following namespace : cv::bioinspired with C++ and in cv.bioinspired with Python
 
 ### Introduction
 
@@ -425,14 +425,14 @@ Python version
 
 @code{.py}
 #import OpenCV module
-import cv2 
+import cv2 as cv
 
 #setup webcam reader
-videoHandler = cv2.VideoCapture(0)
+videoHandler = cv.VideoCapture(0)
 succeed, inputImage=videoHandler.read()
 
 #allocate a retina instance with input size equal to the one of the loaded image
-retina = cv2.bioinspired.createRetina((inputImage.shape[1], inputImage.shape[0]))
+retina = cv.bioinspired.createRetina((inputImage.shape[1], inputImage.shape[0]))
 
 #retina parameters management methods use sample
 #-> save current (here default) retina parameters to a xml file (you may use it only one time to get the file and modify it)
@@ -446,7 +446,7 @@ while stillProcess is True:
 
 	#grab a new frame and display it
 	stillProcess, inputImage=videoHandler.read()
-	cv2.imshow('input frame', inputImage)
+	cv.imshow('input frame', inputImage)
 
 	#run retina on the input image
 	retina.run(inputImage)
@@ -456,11 +456,11 @@ while stillProcess is True:
 	retinaOut_magno=retina.getMagno()
 
 	#draw retina outputs
-	cv2.imshow('retina parvo out', retinaOut_parvo)
-	cv2.imshow('retina magno out', retinaOut_magno)
+	cv.imshow('retina parvo out', retinaOut_parvo)
+	cv.imshow('retina magno out', retinaOut_magno)
 
 	#wait a little to let the time for figures to be drawn
-	cv2.waitKey(2)
+	cv.waitKey(2)
 @endcode
 
 

modules/bioinspired/tutorials/retina_illusion/retina_illusion.markdown

@@ -117,10 +117,10 @@ iterations. This is an arbitrary number that we found experimentally to be (more
 enough
 
 @code{.py}
-import cv2
+import cv2 as cv
 
-inputImage = cv2.imread('checkershadow_illusion4med.jpg', 1)
-retina = cv2.bioinspired.createRetina((inputImage.shape[1], inputImage.shape[0]))
+inputImage = cv.imread('checkershadow_illusion4med.jpg', 1)
+retina = cv.bioinspired.createRetina((inputImage.shape[1], inputImage.shape[0]))
 
 # the retina object is created with default parameters. If you want to read
 # the parameters from an external XML file, uncomment the next line
@@ -134,15 +134,15 @@ for i in range(20):
 retinaOut_parvo = retina.getParvo()
 
 # show both the original image and the processed one
-cv2.imshow('image', inputImage)
-cv2.imshow('retina parvo out', retinaOut_parvo)
+cv.imshow('image', inputImage)
+cv.imshow('retina parvo out', retinaOut_parvo)
 
 # wait for a key to be pressed and exit
-cv2.waitKey(0)
-cv2.destroyAllWindows()
+cv.waitKey(0)
+cv.destroyAllWindows()
 
 # write the output image on a file
-cv2.imwrite('checkershadow_parvo.png', retinaOut_parvo)
+cv.imwrite('checkershadow_parvo.png', retinaOut_parvo)
 @endcode
 
 Whatever method you used to process the image, you should end up

modules/optflow/samples/motempl.py

 #!/usr/bin/env python
 import numpy as np
-import cv2
+import cv2 as cv
 
 MHI_DURATION = 0.5
 DEFAULT_THRESHOLD = 32
@@ -12,12 +12,12 @@ def nothing(dummy):
     pass
 
 def draw_motion_comp(vis, (x, y, w, h), angle, color):
-    cv2.rectangle(vis, (x, y), (x+w, y+h), (0, 255, 0))
+    cv.rectangle(vis, (x, y), (x+w, y+h), (0, 255, 0))
     r = min(w/2, h/2)
     cx, cy = x+w/2, y+h/2
     angle = angle*np.pi/180
-    cv2.circle(vis, (cx, cy), r, color, 3)
-    cv2.line(vis, (cx, cy), (int(cx+np.cos(angle)*r), int(cy+np.sin(angle)*r)), color, 3)
+    cv.circle(vis, (cx, cy), r, color, 3)
+    cv.line(vis, (cx, cy), (int(cx+np.cos(angle)*r), int(cy+np.sin(angle)*r)), color, 3)
 
 if __name__ == '__main__':
     import sys
@@ -26,12 +26,12 @@ if __name__ == '__main__':
     except:
         video_src = 0
 
-    cv2.namedWindow('motempl')
+    cv.namedWindow('motempl')
     visuals = ['input', 'frame_diff', 'motion_hist', 'grad_orient']
-    cv2.createTrackbar('visual', 'motempl', 2, len(visuals)-1, nothing)
-    cv2.createTrackbar('threshold', 'motempl', DEFAULT_THRESHOLD, 255, nothing)
+    cv.createTrackbar('visual', 'motempl', 2, len(visuals)-1, nothing)
+    cv.createTrackbar('threshold', 'motempl', DEFAULT_THRESHOLD, 255, nothing)
 
-    cam = cv2.VideoCapture(video_src)
+    cam = cv.VideoCapture(video_src)
     if not cam.isOpened():
         print("could not open video_src " + str(video_src) + " !\n")
         sys.exit(1)
@@ -48,27 +48,27 @@ if __name__ == '__main__':
         ret, frame = cam.read()
         if ret == False:
             break
-        frame_diff = cv2.absdiff(frame, prev_frame)
-        gray_diff = cv2.cvtColor(frame_diff, cv2.COLOR_BGR2GRAY)
-        thrs = cv2.getTrackbarPos('threshold', 'motempl')
-        ret, motion_mask = cv2.threshold(gray_diff, thrs, 1, cv2.THRESH_BINARY)
-        timestamp = cv2.getTickCount() / cv2.getTickFrequency()
-        cv2.motempl.updateMotionHistory(motion_mask, motion_history, timestamp, MHI_DURATION)
-        mg_mask, mg_orient = cv2.motempl.calcMotionGradient( motion_history, MAX_TIME_DELTA, MIN_TIME_DELTA, apertureSize=5 )
-        seg_mask, seg_bounds = cv2.motempl.segmentMotion(motion_history, timestamp, MAX_TIME_DELTA)
+        frame_diff = cv.absdiff(frame, prev_frame)
+        gray_diff = cv.cvtColor(frame_diff, cv.COLOR_BGR2GRAY)
+        thrs = cv.getTrackbarPos('threshold', 'motempl')
+        ret, motion_mask = cv.threshold(gray_diff, thrs, 1, cv.THRESH_BINARY)
+        timestamp = cv.getTickCount() / cv.getTickFrequency()
+        cv.motempl.updateMotionHistory(motion_mask, motion_history, timestamp, MHI_DURATION)
+        mg_mask, mg_orient = cv.motempl.calcMotionGradient( motion_history, MAX_TIME_DELTA, MIN_TIME_DELTA, apertureSize=5 )
+        seg_mask, seg_bounds = cv.motempl.segmentMotion(motion_history, timestamp, MAX_TIME_DELTA)
 
-        visual_name = visuals[cv2.getTrackbarPos('visual', 'motempl')]
+        visual_name = visuals[cv.getTrackbarPos('visual', 'motempl')]
         if visual_name == 'input':
             vis = frame.copy()
         elif visual_name == 'frame_diff':
             vis = frame_diff.copy()
         elif visual_name == 'motion_hist':
             vis = np.uint8(np.clip((motion_history-(timestamp-MHI_DURATION)) / MHI_DURATION, 0, 1)*255)
-            vis = cv2.cvtColor(vis, cv2.COLOR_GRAY2BGR)
+            vis = cv.cvtColor(vis, cv.COLOR_GRAY2BGR)
         elif visual_name == 'grad_orient':
             hsv[:,:,0] = mg_orient/2
             hsv[:,:,2] = mg_mask*255
-            vis = cv2.cvtColor(hsv, cv2.COLOR_HSV2BGR)
+            vis = cv.cvtColor(hsv, cv.COLOR_HSV2BGR)
 
         for i, rect in enumerate([(0, 0, w, h)] + list(seg_bounds)):
             x, y, rw, rh = rect
@@ -79,16 +79,16 @@ if __name__ == '__main__':
             orient_roi = mg_orient     [y:y+rh,x:x+rw]
             mask_roi   = mg_mask       [y:y+rh,x:x+rw]
             mhi_roi    = motion_history[y:y+rh,x:x+rw]
-            if cv2.norm(silh_roi, cv2.NORM_L1) < area*0.05:
+            if cv.norm(silh_roi, cv.NORM_L1) < area*0.05:
                 continue
-            angle = cv2.motempl.calcGlobalOrientation(orient_roi, mask_roi, mhi_roi, timestamp, MHI_DURATION)
+            angle = cv.motempl.calcGlobalOrientation(orient_roi, mask_roi, mhi_roi, timestamp, MHI_DURATION)
             color = ((255, 0, 0), (0, 0, 255))[i == 0]
             draw_motion_comp(vis, rect, angle, color)
 
-        cv2.putText(vis, visual_name, (20, 20), cv2.FONT_HERSHEY_PLAIN, 1.0, (200,0,0))
-        cv2.imshow('motempl', vis)
+        cv.putText(vis, visual_name, (20, 20), cv.FONT_HERSHEY_PLAIN, 1.0, (200,0,0))
+        cv.imshow('motempl', vis)
 
         prev_frame = frame.copy()
-        if 0xFF & cv2.waitKey(5) == 27:
+        if 0xFF & cv.waitKey(5) == 27:
             break
-    cv2.destroyAllWindows()
+    cv.destroyAllWindows()

modules/optflow/src/learn_prior.py

@@ -3,7 +3,7 @@
 import os
 import sys
 import numpy as np
-import cv2
+import cv2 as cv
 import struct
 import argparse
 from math import sqrt
@@ -73,7 +73,7 @@ def load_flo(flo):
 
 def get_w(m):
     s = m.shape
-    w = cv2.dct(m)
+    w = cv.dct(m)
     w *= 2.0 / sqrt(s[0] * s[1])
     #w[0,0] *= 0.5
     w[:, 0] *= sqrt(0.5)

modules/ovis/samples/aruco_ar_demo.py

-import cv2
 import numpy as np
+import cv2 as cv
 
 # aruco
-adict = cv2.aruco.Dictionary_get(cv2.aruco.DICT_4X4_50)
-cv2.imshow("marker", cv2.aruco.drawMarker(adict, 0, 400))
+adict = cv.aruco.Dictionary_get(cv.aruco.DICT_4X4_50)
+cv.imshow("marker", cv.aruco.drawMarker(adict, 0, 400))
 
 # random calibration data. your mileage may vary.
 imsize = (800, 600)
-K = cv2.getDefaultNewCameraMatrix(np.diag([800, 800, 1]), imsize, True)
+K = cv.getDefaultNewCameraMatrix(np.diag([800, 800, 1]), imsize, True)
 
 # AR scene
-cv2.ovis.addResourceLocation("packs/Sinbad.zip") # shipped with Ogre
+cv.ovis.addResourceLocation("packs/Sinbad.zip") # shipped with Ogre
 
-win = cv2.ovis.createWindow("arucoAR", imsize, flags=0)
+win = cv.ovis.createWindow("arucoAR", imsize, flags=0)
 win.createEntity("figure", "Sinbad.mesh", (0, 0, -5), (-1.57, 0, 0))
 win.createLightEntity("sun", (0, 0, -100))
 
 # video capture
-cap = cv2.VideoCapture(0)
-cap.set(cv2.CAP_PROP_FRAME_WIDTH, imsize[0])
-cap.set(cv2.CAP_PROP_FRAME_HEIGHT, imsize[1])
+cap = cv.VideoCapture(0)
+cap.set(cv.CAP_PROP_FRAME_WIDTH, imsize[0])
+cap.set(cv.CAP_PROP_FRAME_HEIGHT, imsize[1])
 
-while cv2.ovis.renderOneFrame():
+while cv.ovis.renderOneFrame():
     img = cap.read()[1]
     win.setBackground(img)
-    corners, ids = cv2.aruco.detectMarkers(img, adict)[:2]
+    corners, ids = cv.aruco.detectMarkers(img, adict)[:2]
 
-    cv2.waitKey(1)
+    cv.waitKey(1)
 
     if ids is None:
         continue
 
-    rvecs, tvecs = cv2.aruco.estimatePoseSingleMarkers(corners, 5, K, None)[:2]
+    rvecs, tvecs = cv.aruco.estimatePoseSingleMarkers(corners, 5, K, None)[:2]
     win.setCameraPose(tvecs[0].ravel(), rvecs[0].ravel(), invert=True)

modules/ovis/samples/ovis_demo.py

-import cv2
 import numpy as np
+import cv2 as cv
 
 # add some external resources
-cv2.ovis.addResourceLocation("packs/Sinbad.zip")
+cv.ovis.addResourceLocation("packs/Sinbad.zip")
 
 # camera intrinsics
 imsize = (800, 600)
@@ -10,19 +10,19 @@ K = np.diag([800, 800, 1])
 K[:2, 2] = (400, 100) # offset pp
 
 # observer scene
-owin = cv2.ovis.createWindow("VR", imsize)
-cv2.ovis.createGridMesh("ground", (10, 10), (10, 10))
+owin = cv.ovis.createWindow("VR", imsize)
+cv.ovis.createGridMesh("ground", (10, 10), (10, 10))
 owin.createEntity("ground", "ground", rot=(1.57, 0, 0))
 owin.createCameraEntity("cam", K, imsize, 5)
 owin.createEntity("figure", "Sinbad.mesh", (0, -5, 0))  # externally defined mesh
 owin.createLightEntity("sun", (0, 0, -100))
 
 # interaction scene
-iwin = cv2.ovis.createWindow("AR", imsize, cv2.ovis.SCENE_SEPERATE | cv2.ovis.SCENE_INTERACTIVE)
+iwin = cv.ovis.createWindow("AR", imsize, cv.ovis.SCENE_SEPERATE | cv.ovis.SCENE_INTERACTIVE)
 iwin.createEntity("figure", "Sinbad.mesh", (0, -5, 0))
 iwin.createLightEntity("sun", (0, 0, -100))
 iwin.setCameraIntrinsics(K, imsize)
 
-while cv2.ovis.renderOneFrame():
+while cv.ovis.renderOneFrame():
     R, t = iwin.getCameraPose()
     owin.setEntityPose("cam", t, R)

modules/reg/samples/reg_shift.py

 #!/usr/bin/python
 
-import cv2
+import cv2 as cv
 import numpy as np
 import sys
 
-img1 = cv2.imread(sys.argv[1])
+img1 = cv.imread(sys.argv[1])
 img1 = img1.astype(np.float32)
 shift = np.array([5., 5.])
-mapTest = cv2.reg.MapShift(shift)
+mapTest = cv.reg.MapShift(shift)
 
 img2 = mapTest.warp(img1)
 
-mapper = cv2.reg.MapperGradShift()
-mappPyr = cv2.reg.MapperPyramid(mapper)
+mapper = cv.reg.MapperGradShift()
+mappPyr = cv.reg.MapperPyramid(mapper)
 
 resMap = mappPyr.calculate(img1, img2)
-mapShift = cv2.reg.MapTypeCaster_toShift(resMap)
+mapShift = cv.reg.MapTypeCaster_toShift(resMap)
 
 print(mapShift.getShift())

modules/surface_matching/samples/ppf_icp.py

-import cv2
+import cv2 as cv
 import numpy as np
 
 def rotation(theta):
@@ -42,7 +42,7 @@ Rt = np.vstack((
     np.array([0, 0, 0, 1])
 )).astype(np.float32)
 
-icp = cv2.ppf_match_3d_ICP(100)
+icp = cv.ppf_match_3d_ICP(100)
 
 I = np.eye(4)
 print("Unaligned error:\t%.6f" % np.linalg.norm(I - Rt))

modules/text/samples/deeptextdetection.py

@@ -2,7 +2,7 @@
 #!/usr/bin/python
 import sys
 import os
-import cv2
+import cv2 as cv
 import numpy as np
 
 def main():
@@ -19,8 +19,8 @@ def main():
         print " See the documentation of text::TextDetectorCNN class to get download links."
         quit()
 
-    img = cv2.imread(str(sys.argv[1]))
-    textSpotter = cv2.text.TextDetectorCNN_create("textbox.prototxt", "TextBoxes_icdar13.caffemodel")
+    img = cv.imread(str(sys.argv[1]))
+    textSpotter = cv.text.TextDetectorCNN_create("textbox.prototxt", "TextBoxes_icdar13.caffemodel")
     rects, outProbs = textSpotter.detect(img);
     vis = img.copy()
     thres = 0.6
@@ -28,10 +28,10 @@ def main():
     for r in range(np.shape(rects)[0]):
         if outProbs[r] > thres:
             rect = rects[r]
-            cv2.rectangle(vis, (rect[0],rect[1]), (rect[0] + rect[2], rect[1] + rect[3]), (255, 0, 0), 2)
+            cv.rectangle(vis, (rect[0],rect[1]), (rect[0] + rect[2], rect[1] + rect[3]), (255, 0, 0), 2)
 
-    cv2.imshow("Text detection result", vis)
-    cv2.waitKey()
+    cv.imshow("Text detection result", vis)
+    cv.waitKey()
 
 if __name__ == "__main__":
     main()

modules/text/samples/detect_er_chars.py

@@ -3,7 +3,7 @@
 import sys
 import os
 
-import cv2
+import cv2 as cv
 import numpy as np
 
 print('\ndetect_er_chars.py')
@@ -17,22 +17,22 @@ if (len(sys.argv) < 2):
 
 pathname = os.path.dirname(sys.argv[0])
 
-img  = cv2.imread(str(sys.argv[1]))
-gray = cv2.imread(str(sys.argv[1]),0)
+img  = cv.imread(str(sys.argv[1]))
+gray = cv.imread(str(sys.argv[1]),0)
 
-erc1 = cv2.text.loadClassifierNM1(pathname+'/trained_classifierNM1.xml')
-er1 = cv2.text.createERFilterNM1(erc1)
+erc1 = cv.text.loadClassifierNM1(pathname+'/trained_classifierNM1.xml')
+er1 = cv.text.createERFilterNM1(erc1)
 
-erc2 = cv2.text.loadClassifierNM2(pathname+'/trained_classifierNM2.xml')
-er2 = cv2.text.createERFilterNM2(erc2)
+erc2 = cv.text.loadClassifierNM2(pathname+'/trained_classifierNM2.xml')
+er2 = cv.text.createERFilterNM2(erc2)
 
-regions = cv2.text.detectRegions(gray,er1,er2)
+regions = cv.text.detectRegions(gray,er1,er2)
 
 #Visualization
-rects = [cv2.boundingRect(p.reshape(-1, 1, 2)) for p in regions]
+rects = [cv.boundingRect(p.reshape(-1, 1, 2)) for p in regions]
 for rect in rects:
-  cv2.rectangle(img, rect[0:2], (rect[0]+rect[2],rect[1]+rect[3]), (0, 0, 0), 2)
+  cv.rectangle(img, rect[0:2], (rect[0]+rect[2],rect[1]+rect[3]), (0, 0, 0), 2)
 for rect in rects:
-  cv2.rectangle(img, rect[0:2], (rect[0]+rect[2],rect[1]+rect[3]), (255, 255, 255), 1)
-cv2.imshow("Text detection result", img)
-cv2.waitKey(0)
+  cv.rectangle(img, rect[0:2], (rect[0]+rect[2],rect[1]+rect[3]), (255, 255, 255), 1)
+cv.imshow("Text detection result", img)
+cv.waitKey(0)

modules/text/samples/textdetection.py

@@ -3,7 +3,7 @@
 import sys
 import os
 
-import cv2
+import cv2 as cv
 import numpy as np
 
 print('\ntextdetection.py')
@@ -18,13 +18,13 @@ if (len(sys.argv) < 2):
 pathname = os.path.dirname(sys.argv[0])
 
 
-img      = cv2.imread(str(sys.argv[1]))
+img      = cv.imread(str(sys.argv[1]))
 # for visualization
 vis      = img.copy()
 
 
 # Extract channels to be processed individually
-channels = cv2.text.computeNMChannels(img)
+channels = cv.text.computeNMChannels(img)
 # Append negative channels to detect ER- (bright regions over dark background)
 cn = len(channels)-1
 for c in range(0,cn):
@@ -35,24 +35,24 @@ print("Extracting Class Specific Extremal Regions from "+str(len(channels))+" ch
 print("    (...) this may take a while (...)")
 for channel in channels:
 
-  erc1 = cv2.text.loadClassifierNM1(pathname+'/trained_classifierNM1.xml')
-  er1 = cv2.text.createERFilterNM1(erc1,16,0.00015,0.13,0.2,True,0.1)
+  erc1 = cv.text.loadClassifierNM1(pathname+'/trained_classifierNM1.xml')
+  er1 = cv.text.createERFilterNM1(erc1,16,0.00015,0.13,0.2,True,0.1)
 
-  erc2 = cv2.text.loadClassifierNM2(pathname+'/trained_classifierNM2.xml')
-  er2 = cv2.text.createERFilterNM2(erc2,0.5)
+  erc2 = cv.text.loadClassifierNM2(pathname+'/trained_classifierNM2.xml')
+  er2 = cv.text.createERFilterNM2(erc2,0.5)
 
-  regions = cv2.text.detectRegions(channel,er1,er2)
+  regions = cv.text.detectRegions(channel,er1,er2)
 
-  rects = cv2.text.erGrouping(img,channel,[r.tolist() for r in regions])
-  #rects = cv2.text.erGrouping(img,channel,[x.tolist() for x in regions], cv2.text.ERGROUPING_ORIENTATION_ANY,'../../GSoC2014/opencv_contrib/modules/text/samples/trained_classifier_erGrouping.xml',0.5)
+  rects = cv.text.erGrouping(img,channel,[r.tolist() for r in regions])
+  #rects = cv.text.erGrouping(img,channel,[x.tolist() for x in regions], cv.text.ERGROUPING_ORIENTATION_ANY,'../../GSoC2014/opencv_contrib/modules/text/samples/trained_classifier_erGrouping.xml',0.5)
 
   #Visualization
   for r in range(0,np.shape(rects)[0]):
     rect = rects[r]
-    cv2.rectangle(vis, (rect[0],rect[1]), (rect[0]+rect[2],rect[1]+rect[3]), (0, 0, 0), 2)
-    cv2.rectangle(vis, (rect[0],rect[1]), (rect[0]+rect[2],rect[1]+rect[3]), (255, 255, 255), 1)
+    cv.rectangle(vis, (rect[0],rect[1]), (rect[0]+rect[2],rect[1]+rect[3]), (0, 0, 0), 2)
+    cv.rectangle(vis, (rect[0],rect[1]), (rect[0]+rect[2],rect[1]+rect[3]), (255, 255, 255), 1)
 
 
 #Visualization
-cv2.imshow("Text detection result", vis)
-cv2.waitKey(0)
+cv.imshow("Text detection result", vis)
+cv.waitKey(0)

modules/tracking/samples/multitracker.py

 import numpy as np
-import cv2
+import cv2 as cv
 import sys
 
 if len(sys.argv) != 2:
@@ -8,9 +8,9 @@ if len(sys.argv) != 2:
 
 print('Select 3 tracking targets')
 
-cv2.namedWindow("tracking")
-camera = cv2.VideoCapture(sys.argv[1])
-tracker = cv2.MultiTracker_create()
+cv.namedWindow("tracking")
+camera = cv.VideoCapture(sys.argv[1])
+tracker = cv.MultiTracker_create()
 init_once = False
 
 ok, image=camera.read()
@@ -18,9 +18,9 @@ if not ok:
     print('Failed to read video')
     exit()
 
-bbox1 = cv2.selectROI('tracking', image)
-bbox2 = cv2.selectROI('tracking', image)
-bbox3 = cv2.selectROI('tracking', image)
+bbox1 = cv.selectROI('tracking', image)
+bbox2 = cv.selectROI('tracking', image)
+bbox3 = cv.selectROI('tracking', image)
 
 while camera.isOpened():
     ok, image=camera.read()
@@ -29,9 +29,9 @@ while camera.isOpened():
         break
 
     if not init_once:
-        ok = tracker.add(cv2.TrackerMIL_create(), image, bbox1)
-        ok = tracker.add(cv2.TrackerMIL_create(), image, bbox2)
-        ok = tracker.add(cv2.TrackerMIL_create(), image, bbox3)
+        ok = tracker.add(cv.TrackerMIL_create(), image, bbox1)
+        ok = tracker.add(cv.TrackerMIL_create(), image, bbox2)
+        ok = tracker.add(cv.TrackerMIL_create(), image, bbox3)
         init_once = True
 
     ok, boxes = tracker.update(image)
@@ -40,8 +40,8 @@ while camera.isOpened():
     for newbox in boxes:
         p1 = (int(newbox[0]), int(newbox[1]))
         p2 = (int(newbox[0] + newbox[2]), int(newbox[1] + newbox[3]))
-        cv2.rectangle(image, p1, p2, (200,0,0))
+        cv.rectangle(image, p1, p2, (200,0,0))
 
-    cv2.imshow('tracking', image)
-    k = cv2.waitKey(1)
+    cv.imshow('tracking', image)
+    k = cv.waitKey(1)
     if k == 27 : break # esc pressed

modules/tracking/samples/tracker.py

 import numpy as np
-import cv2
+import cv2 as cv
 import sys
 
 if len(sys.argv) != 2:
     print('Input video name is missing')
     exit()
 
-cv2.namedWindow("tracking")
-camera = cv2.VideoCapture(sys.argv[1])
+cv.namedWindow("tracking")
+camera = cv.VideoCapture(sys.argv[1])
 ok, image=camera.read()
 if not ok:
     print('Failed to read video')
     exit()
-bbox = cv2.selectROI("tracking", image)
-tracker = cv2.TrackerMIL_create()
+bbox = cv.selectROI("tracking", image)
+tracker = cv.TrackerMIL_create()
 init_once = False
 
 while camera.isOpened():
@@ -32,8 +32,8 @@ while camera.isOpened():
     if ok:
         p1 = (int(newbox[0]), int(newbox[1]))
         p2 = (int(newbox[0] + newbox[2]), int(newbox[1] + newbox[3]))
-        cv2.rectangle(image, p1, p2, (200,0,0))
+        cv.rectangle(image, p1, p2, (200,0,0))
 
-    cv2.imshow("tracking", image)
-    k = cv2.waitKey(1) & 0xff
+    cv.imshow("tracking", image)
+    k = cv.waitKey(1) & 0xff
     if k == 27 : break # esc pressed

modules/ximgproc/samples/edgeboxes_demo.py

@@ -7,7 +7,7 @@ Usage:
   edgeboxes_demo.py [<model>] [<input_image>]
 '''
 
-import cv2
+import cv2 as cv
 import numpy as np
 import sys
 
@@ -15,24 +15,24 @@ if __name__ == '__main__':
     print(__doc__)
 
     model = sys.argv[1]
-    im = cv2.imread(sys.argv[2])
+    im = cv.imread(sys.argv[2])
 
-    edge_detection = cv2.ximgproc.createStructuredEdgeDetection(model)
-    rgb_im = cv2.cvtColor(im, cv2.COLOR_BGR2RGB)
+    edge_detection = cv.ximgproc.createStructuredEdgeDetection(model)
+    rgb_im = cv.cvtColor(im, cv.COLOR_BGR2RGB)
     edges = edge_detection.detectEdges(np.float32(rgb_im) / 255.0)
 
     orimap = edge_detection.computeOrientation(edges)
     edges = edge_detection.edgesNms(edges, orimap)
 
-    edge_boxes = cv2.ximgproc.createEdgeBoxes()
+    edge_boxes = cv.ximgproc.createEdgeBoxes()
     edge_boxes.setMaxBoxes(30)
     boxes = edge_boxes.getBoundingBoxes(edges, orimap)
 
     for b in boxes:
         x, y, w, h = b
-        cv2.rectangle(im, (x, y), (x+w, y+h), (0, 255, 0), 1, cv2.LINE_AA)
+        cv.rectangle(im, (x, y), (x+w, y+h), (0, 255, 0), 1, cv.LINE_AA)
 
-    cv2.imshow("edges", edges)
-    cv2.imshow("edgeboxes", im)
-    cv2.waitKey(0)
-    cv2.destroyAllWindows()
+    cv.imshow("edges", edges)
+    cv.imshow("edgeboxes", im)
+    cv.waitKey(0)
+    cv.destroyAllWindows()

modules/ximgproc/samples/findredlinedpolygonfromgooglemaps.py

@@ -4,7 +4,7 @@
 
 import numpy as np
 import argparse
-import cv2
+import cv2 as cv
 
 # construct the argument parse and parse the arguments
 ap = argparse.ArgumentParser()
@@ -12,18 +12,18 @@ ap.add_argument("-i", "--image", help = "path to the image file")
 args = vars(ap.parse_args())
 
 # load the image
-image = cv2.imread(args["image"])
+image = cv.imread(args["image"])
 lower = np.array([20,0,155])
 upper = np.array([255,120,250])
-shapeMask = cv2.inRange(image, lower, upper)
+shapeMask = cv.inRange(image, lower, upper)
 
 # find the contours in the mask
-(cnts, _) = cv2.findContours(shapeMask.copy(), cv2.RETR_EXTERNAL,
-    cv2.CHAIN_APPROX_SIMPLE)
-cv2.imshow("Mask", shapeMask)
+(cnts, _) = cv.findContours(shapeMask.copy(), cv.RETR_EXTERNAL,
+    cv.CHAIN_APPROX_SIMPLE)
+cv.imshow("Mask", shapeMask)
 
 # loop over the contours
 for c in cnts:
-    cv2.drawContours(image, [c], -1, (0, 255, 0), 2)
-    cv2.imshow("Image", image)
-    cv2.waitKey(0)
\ No newline at end of file
+    cv.drawContours(image, [c], -1, (0, 255, 0), 2)
+    cv.imshow("Image", image)
+    cv.waitKey(0)
\ No newline at end of file

modules/ximgproc/samples/selectivesearchsegmentation_demo.py

@@ -10,16 +10,16 @@ Usage:
 Use "a" to display less rects, 'd' to display more rects, "q" to quit.
 '''
 
-import cv2
+import cv2 as cv
 import sys
 
 if __name__ == '__main__':
-    img = cv2.imread(sys.argv[1])
+    img = cv.imread(sys.argv[1])
 
-    cv2.setUseOptimized(True)
-    cv2.setNumThreads(8)
+    cv.setUseOptimized(True)
+    cv.setNumThreads(8)
 
-    gs = cv2.ximgproc.segmentation.createSelectiveSearchSegmentation()
+    gs = cv.ximgproc.segmentation.createSelectiveSearchSegmentation()
     gs.setBaseImage(img)
 
     if (sys.argv[2][0] == 's'):
@@ -43,10 +43,10 @@ if __name__ == '__main__':
         for i in range(len(rects)):
             if (i < nb_rects):
                 x, y, w, h = rects[i]
-                cv2.rectangle(wimg, (x, y), (x+w, y+h), (0, 255, 0), 1, cv2.LINE_AA)
+                cv.rectangle(wimg, (x, y), (x+w, y+h), (0, 255, 0), 1, cv.LINE_AA)
 
-        cv2.imshow("Output", wimg);
-        c = cv2.waitKey()
+        cv.imshow("Output", wimg);
+        c = cv.waitKey()
 
         if (c == 100):
             nb_rects += 10
@@ -57,4 +57,4 @@ if __name__ == '__main__':
         elif (c == 113):
             break
 
-    cv2.destroyAllWindows()
+    cv.destroyAllWindows()

modules/xphoto/samples/color_balance_benchmark.py

@@ -3,7 +3,7 @@ from __future__ import print_function
 import os, sys, argparse, json
 import numpy as np
 import scipy.io
-import cv2
+import cv2 as cv
 import timeit
 from learn_color_balance import load_ground_truth
 
@@ -44,7 +44,7 @@ def evaluate(im, algo, gt_illuminant, i, range_thresh, bin_num, dst_folder, mode
     new_im = None
     start_time = timeit.default_timer()
     if algo=="grayworld":
-        inst = cv2.xphoto.createGrayworldWB()
+        inst = cv.xphoto.createGrayworldWB()
         inst.setSaturationThreshold(0.95)
         new_im = inst.balanceWhite(im)
     elif algo=="nothing":
@@ -53,7 +53,7 @@ def evaluate(im, algo, gt_illuminant, i, range_thresh, bin_num, dst_folder, mode
         model_path = ""
         if len(algo.split(":"))>1:
             model_path = os.path.join(model_folder, algo.split(":")[1])
-        inst = cv2.xphoto.createLearningBasedWB(model_path)
+        inst = cv.xphoto.createLearningBasedWB(model_path)
         inst.setRangeMaxVal(range_thresh)
         inst.setSaturationThreshold(0.98)
         inst.setHistBinNum(bin_num)
@@ -63,14 +63,14 @@ def evaluate(im, algo, gt_illuminant, i, range_thresh, bin_num, dst_folder, mode
         g1 = float(1.0 / gains[2])
         g2 = float(1.0 / gains[1])
         g3 = float(1.0 / gains[0])
-        new_im = cv2.xphoto.applyChannelGains(im, g1, g2, g3)
+        new_im = cv.xphoto.applyChannelGains(im, g1, g2, g3)
     time = 1000*(timeit.default_timer() - start_time) #time in ms
 
     if len(dst_folder)>0:
         if not os.path.exists(dst_folder):
             os.makedirs(dst_folder)
         im_name = ("%04d_" % i) + algo.replace(":","_") + ".jpg"
-        cv2.imwrite(os.path.join(dst_folder, im_name), stretch_to_8bit(new_im))
+        cv.imwrite(os.path.join(dst_folder, im_name), stretch_to_8bit(new_im))
 
     #recover the illuminant from the color balancing result, assuming the standard model:
     estimated_illuminant = [0, 0, 0]
@@ -248,7 +248,7 @@ if __name__ == '__main__':
             if file not in state[algorithm].keys() and\
              ((i>=img_range[0] and i<img_range[1]) or img_range[0]==img_range[1]==0):
                 cur_path = os.path.join(args.input_folder, file)
-                im = cv2.imread(cur_path, -1).astype(np.float32)
+                im = cv.imread(cur_path, -1).astype(np.float32)
                 im -= black_levels[i]
                 range_thresh = 255
                 if len(args.input_bit_depth)>0:

modules/xphoto/samples/learn_color_balance.py

@@ -4,7 +4,7 @@ import os, sys, argparse
 import numpy as np
 import scipy.io
 from sklearn.tree import DecisionTreeRegressor
-import cv2
+import cv2 as cv
 import random
 
 
@@ -96,7 +96,7 @@ def generate_code(model, input_params, use_YML, out_file):
             thresh_vals += local_thresh_vals
             leaf_vals += local_leaf_vals
     if use_YML:
-        fs = cv2.FileStorage(out_file, 1)
+        fs = cv.FileStorage(out_file, 1)
         fs.write("num_trees", len(model))
         fs.write("num_tree_nodes", 2**depth)
         fs.write("feature_idx", np.array(feature_idx).astype(np.uint8))
@@ -246,14 +246,14 @@ if __name__ == '__main__':
     i=0
     sz = len(img_files)
     random.seed(1234)
-    inst = cv2.xphoto.createLearningBasedWB()
+    inst = cv.xphoto.createLearningBasedWB()
     inst.setRangeMaxVal(255)
     inst.setSaturationThreshold(0.98)
     inst.setHistBinNum(hist_bin_num)
     for file in img_files:
         if (i>=img_range[0] and i<img_range[1]) or (img_range[0]==img_range[1]==0):
             cur_path = os.path.join(args.input_folder,file)
-            im = cv2.imread(cur_path, -1).astype(np.float32)
+            im = cv.imread(cur_path, -1).astype(np.float32)
             im -= black_levels[i]
             im_8bit = convert_to_8bit(im)
             cur_img_features = inst.extractSimpleFeatures(im_8bit, None)

samples/python2/common.py

@@ -5,7 +5,7 @@ This module contains some common routines used by other samples.
 '''
 
 import numpy as np
-import cv2
+import cv2 as cv
 
 # built-in modules
 import os
@@ -63,7 +63,7 @@ def lookat(eye, target, up = (0, 0, 1)):
     return R, tvec
 
 def mtx2rvec(R):
-    w, u, vt = cv2.SVDecomp(R - np.eye(3))
+    w, u, vt = cv.SVDecomp(R - np.eye(3))
     p = vt[0] + u[:,0]*w[0]    # same as np.dot(R, vt[0])
     c = np.dot(vt[0], p)
     s = np.dot(vt[1], p)
@@ -71,8 +71,8 @@ def mtx2rvec(R):
     return axis * np.arctan2(s, c)
 
 def draw_str(dst, (x, y), s):
-    cv2.putText(dst, s, (x+1, y+1), cv2.FONT_HERSHEY_PLAIN, 1.0, (0, 0, 0), thickness = 2, lineType=cv2.LINE_AA)
-    cv2.putText(dst, s, (x, y), cv2.FONT_HERSHEY_PLAIN, 1.0, (255, 255, 255), lineType=cv2.LINE_AA)
+    cv.putText(dst, s, (x+1, y+1), cv.FONT_HERSHEY_PLAIN, 1.0, (0, 0, 0), thickness = 2, lineType=cv.LINE_AA)
+    cv.putText(dst, s, (x, y), cv.FONT_HERSHEY_PLAIN, 1.0, (255, 255, 255), lineType=cv.LINE_AA)
 
 class Sketcher:
     def __init__(self, windowname, dests, colors_func):
@@ -82,21 +82,21 @@ class Sketcher:
         self.colors_func = colors_func
         self.dirty = False
         self.show()
-        cv2.setMouseCallback(self.windowname, self.on_mouse)
+        cv.setMouseCallback(self.windowname, self.on_mouse)
 
     def show(self):
-        cv2.imshow(self.windowname, self.dests[0])
+        cv.imshow(self.windowname, self.dests[0])
 
     def on_mouse(self, event, x, y, flags, param):
         pt = (x, y)
-        if event == cv2.EVENT_LBUTTONDOWN:
+        if event == cv.EVENT_LBUTTONDOWN:
             self.prev_pt = pt
-        elif event == cv2.EVENT_LBUTTONUP:
+        elif event == cv.EVENT_LBUTTONUP:
             self.prev_pt = None
 
-        if self.prev_pt and flags & cv2.EVENT_FLAG_LBUTTON:
+        if self.prev_pt and flags & cv.EVENT_FLAG_LBUTTON:
             for dst, color in zip(self.dests, self.colors_func()):
-                cv2.line(dst, self.prev_pt, pt, color, 5)
+                cv.line(dst, self.prev_pt, pt, color, 5)
             self.dirty = True
             self.prev_pt = pt
             self.show()
@@ -131,7 +131,7 @@ def nothing(*arg, **kw):
     pass
 
 def clock():
-    return cv2.getTickCount() / cv2.getTickFrequency()
+    return cv.getTickCount() / cv.getTickFrequency()
 
 @contextmanager
 def Timer(msg):
@@ -157,15 +157,15 @@ class RectSelector:
     def __init__(self, win, callback):
         self.win = win
         self.callback = callback
-        cv2.setMouseCallback(win, self.onmouse)
+        cv.setMouseCallback(win, self.onmouse)
         self.drag_start = None
         self.drag_rect = None
     def onmouse(self, event, x, y, flags, param):
         x, y = np.int16([x, y]) # BUG
-        if event == cv2.EVENT_LBUTTONDOWN:
+        if event == cv.EVENT_LBUTTONDOWN:
             self.drag_start = (x, y)
         if self.drag_start:
-            if flags & cv2.EVENT_FLAG_LBUTTON:
+            if flags & cv.EVENT_FLAG_LBUTTON:
                 xo, yo = self.drag_start
                 x0, y0 = np.minimum([xo, yo], [x, y])
                 x1, y1 = np.maximum([xo, yo], [x, y])
@@ -182,7 +182,7 @@ class RectSelector:
         if not self.drag_rect:
             return False
         x0, y0, x1, y1 = self.drag_rect
-        cv2.rectangle(vis, (x0, y0), (x1, y1), (0, 255, 0), 2)
+        cv.rectangle(vis, (x0, y0), (x1, y1), (0, 255, 0), 2)
         return True
     @property
     def dragging(self):
@@ -217,4 +217,4 @@ def mdot(*args):
 def draw_keypoints(vis, keypoints, color = (0, 255, 255)):
     for kp in keypoints:
             x, y = kp.pt
-            cv2.circle(vis, (int(x), int(y)), 2, color)
+            cv.circle(vis, (int(x), int(y)), 2, color)

samples/python2/dis_opt_flow.py

@@ -17,7 +17,7 @@ ESC - exit
 from __future__ import print_function
 
 import numpy as np
-import cv2
+import cv2 as cv
 import video
 
 
@@ -27,10 +27,10 @@ def draw_flow(img, flow, step=16):
     fx, fy = flow[y,x].T
     lines = np.vstack([x, y, x+fx, y+fy]).T.reshape(-1, 2, 2)
     lines = np.int32(lines + 0.5)
-    vis = cv2.cvtColor(img, cv2.COLOR_GRAY2BGR)
-    cv2.polylines(vis, lines, 0, (0, 255, 0))
+    vis = cv.cvtColor(img, cv.COLOR_GRAY2BGR)
+    cv.polylines(vis, lines, 0, (0, 255, 0))
     for (x1, y1), (x2, y2) in lines:
-        cv2.circle(vis, (x1, y1), 1, (0, 255, 0), -1)
+        cv.circle(vis, (x1, y1), 1, (0, 255, 0), -1)
     return vis
 
 
@@ -43,7 +43,7 @@ def draw_hsv(flow):
     hsv[...,0] = ang*(180/np.pi/2)
     hsv[...,1] = 255
     hsv[...,2] = np.minimum(v*4, 255)
-    bgr = cv2.cvtColor(hsv, cv2.COLOR_HSV2BGR)
+    bgr = cv.cvtColor(hsv, cv.COLOR_HSV2BGR)
     return bgr
 
 
@@ -52,7 +52,7 @@ def warp_flow(img, flow):
     flow = -flow
     flow[:,:,0] += np.arange(w)
     flow[:,:,1] += np.arange(h)[:,np.newaxis]
-    res = cv2.remap(img, flow, None, cv2.INTER_LINEAR)
+    res = cv.remap(img, flow, None, cv.INTER_LINEAR)
     return res
 
 
@@ -66,19 +66,19 @@ if __name__ == '__main__':
 
     cam = video.create_capture(fn)
     ret, prev = cam.read()
-    prevgray = cv2.cvtColor(prev, cv2.COLOR_BGR2GRAY)
+    prevgray = cv.cvtColor(prev, cv.COLOR_BGR2GRAY)
     show_hsv = False
     show_glitch = False
     use_spatial_propagation = False
     use_temporal_propagation = True
     cur_glitch = prev.copy()
-    inst = cv2.optflow.createOptFlow_DIS(cv2.optflow.DISOPTICAL_FLOW_PRESET_MEDIUM)
+    inst = cv.optflow.createOptFlow_DIS(cv.optflow.DISOPTICAL_FLOW_PRESET_MEDIUM)
     inst.setUseSpatialPropagation(use_spatial_propagation)
 
     flow = None
     while True:
         ret, img = cam.read()
-        gray = cv2.cvtColor(img, cv2.COLOR_BGR2GRAY)
+        gray = cv.cvtColor(img, cv.COLOR_BGR2GRAY)
         if flow is not None and use_temporal_propagation:
             #warp previous flow to get an initial approximation for the current flow:
             flow = inst.calc(prevgray, gray, warp_flow(flow,flow))
@@ -86,14 +86,14 @@ if __name__ == '__main__':
             flow = inst.calc(prevgray, gray, None)
         prevgray = gray
 
-        cv2.imshow('flow', draw_flow(gray, flow))
+        cv.imshow('flow', draw_flow(gray, flow))
         if show_hsv:
-            cv2.imshow('flow HSV', draw_hsv(flow))
+            cv.imshow('flow HSV', draw_hsv(flow))
         if show_glitch:
             cur_glitch = warp_flow(cur_glitch, flow)
-            cv2.imshow('glitch', cur_glitch)
+            cv.imshow('glitch', cur_glitch)
 
-        ch = 0xFF & cv2.waitKey(5)
+        ch = 0xFF & cv.waitKey(5)
         if ch == 27:
             break
         if ch == ord('1'):
@@ -111,4 +111,4 @@ if __name__ == '__main__':
         if ch == ord('4'):
             use_temporal_propagation = not use_temporal_propagation
             print('temporal propagation is', ['off', 'on'][use_temporal_propagation])
-    cv2.destroyAllWindows()
+    cv.destroyAllWindows()

samples/python2/seeds.py

@@ -10,7 +10,7 @@ Usage:
 '''
 
 import numpy as np
-import cv2
+import cv2 as cv
 
 # relative module
 import video
@@ -30,9 +30,9 @@ if __name__ == '__main__':
     def nothing(*arg):
         pass
 
-    cv2.namedWindow('SEEDS')
-    cv2.createTrackbar('Number of Superpixels', 'SEEDS', 400, 1000, nothing)
-    cv2.createTrackbar('Iterations', 'SEEDS', 4, 12, nothing)
+    cv.namedWindow('SEEDS')
+    cv.createTrackbar('Number of Superpixels', 'SEEDS', 400, 1000, nothing)
+    cv.createTrackbar('Iterations', 'SEEDS', 4, 12, nothing)
 
     seeds = None
     display_mode = 0
@@ -44,14 +44,14 @@ if __name__ == '__main__':
     cap = video.create_capture(fn)
     while True:
         flag, img = cap.read()
-        converted_img = cv2.cvtColor(img, cv2.COLOR_BGR2HSV)
+        converted_img = cv.cvtColor(img, cv.COLOR_BGR2HSV)
         height,width,channels = converted_img.shape
-        num_superpixels_new = cv2.getTrackbarPos('Number of Superpixels', 'SEEDS')
-        num_iterations = cv2.getTrackbarPos('Iterations', 'SEEDS')
+        num_superpixels_new = cv.getTrackbarPos('Number of Superpixels', 'SEEDS')
+        num_iterations = cv.getTrackbarPos('Iterations', 'SEEDS')
 
         if not seeds or num_superpixels_new != num_superpixels:
             num_superpixels = num_superpixels_new
-            seeds = cv2.ximgproc.createSuperpixelSEEDS(width, height, channels,
+            seeds = cv.ximgproc.createSuperpixelSEEDS(width, height, channels,
                     num_superpixels, num_levels, prior, num_histogram_bins)
             color_img = np.zeros((height,width,3), np.uint8)
             color_img[:] = (0, 0, 255)
@@ -71,21 +71,21 @@ if __name__ == '__main__':
         mask = seeds.getLabelContourMask(False)
 
         # stitch foreground & background together
-        mask_inv = cv2.bitwise_not(mask)
-        result_bg = cv2.bitwise_and(img, img, mask=mask_inv)
-        result_fg = cv2.bitwise_and(color_img, color_img, mask=mask)
-        result = cv2.add(result_bg, result_fg)
+        mask_inv = cv.bitwise_not(mask)
+        result_bg = cv.bitwise_and(img, img, mask=mask_inv)
+        result_fg = cv.bitwise_and(color_img, color_img, mask=mask)
+        result = cv.add(result_bg, result_fg)
 
         if display_mode == 0:
-            cv2.imshow('SEEDS', result)
+            cv.imshow('SEEDS', result)
         elif display_mode == 1:
-            cv2.imshow('SEEDS', mask)
+            cv.imshow('SEEDS', mask)
         else:
-            cv2.imshow('SEEDS', labels)
+            cv.imshow('SEEDS', labels)
 
-        ch = cv2.waitKey(1)
+        ch = cv.waitKey(1)
         if ch == 27:
             break
         elif ch & 0xff == ord(' '):
             display_mode = (display_mode + 1) % 3
-    cv2.destroyAllWindows()
+    cv.destroyAllWindows()

samples/python2/video.py

@@ -32,7 +32,7 @@ Keys:
 import numpy as np
 from numpy import pi, sin, cos
 
-import cv2
+import cv2 as cv
 
 # built-in modules
 from time import clock
@@ -45,14 +45,14 @@ class VideoSynthBase(object):
         self.bg = None
         self.frame_size = (640, 480)
         if bg is not None:
-            self.bg = cv2.imread(bg, 1)
+            self.bg = cv.imread(bg, 1)
             h, w = self.bg.shape[:2]
             self.frame_size = (w, h)
 
         if size is not None:
             w, h = map(int, size.split('x'))
             self.frame_size = (w, h)
-            self.bg = cv2.resize(self.bg, self.frame_size)
+            self.bg = cv.resize(self.bg, self.frame_size)
 
         self.noise = float(noise)
 
@@ -71,8 +71,8 @@ class VideoSynthBase(object):
 
         if self.noise > 0.0:
             noise = np.zeros((h, w, 3), np.int8)
-            cv2.randn(noise, np.zeros(3), np.ones(3)*255*self.noise)
-            buf = cv2.add(buf, noise, dtype=cv2.CV_8UC3)
+            cv.randn(noise, np.zeros(3), np.ones(3)*255*self.noise)
+            buf = cv.add(buf, noise, dtype=cv.CV_8UC3)
         return True, buf
 
     def isOpened(self):
@@ -102,10 +102,10 @@ class Chess(VideoSynthBase):
         self.t = 0
 
     def draw_quads(self, img, quads, color = (0, 255, 0)):
-        img_quads = cv2.projectPoints(quads.reshape(-1, 3), self.rvec, self.tvec, self.K, self.dist_coef) [0]
+        img_quads = cv.projectPoints(quads.reshape(-1, 3), self.rvec, self.tvec, self.K, self.dist_coef) [0]
         img_quads.shape = quads.shape[:2] + (2,)
         for q in img_quads:
-            cv2.fillConvexPoly(img, np.int32(q*4), color, cv2.LINE_AA, shift=2)
+            cv.fillConvexPoly(img, np.int32(q*4), color, cv.LINE_AA, shift=2)
 
     def render(self, dst):
         t = self.t
@@ -156,11 +156,11 @@ def create_capture(source = 0, fallback = presets['chess']):
         try: cap = Class(**params)
         except: pass
     else:
-        cap = cv2.VideoCapture(source)
+        cap = cv.VideoCapture(source)
         if 'size' in params:
             w, h = map(int, params['size'].split('x'))
-            cap.set(cv2.CAP_PROP_FRAME_WIDTH, w)
-            cap.set(cv2.CAP_PROP_FRAME_HEIGHT, h)
+            cap.set(cv.CAP_PROP_FRAME_WIDTH, w)
+            cap.set(cv.CAP_PROP_FRAME_HEIGHT, h)
     if cap is None or not cap.isOpened():
         print 'Warning: unable to open video source: ', source
         if fallback is not None:
@@ -186,14 +186,14 @@ if __name__ == '__main__':
         for i, cap in enumerate(caps):
             ret, img = cap.read()
             imgs.append(img)
-            cv2.imshow('capture %d' % i, img)
-        ch = 0xFF & cv2.waitKey(1)
+            cv.imshow('capture %d' % i, img)
+        ch = 0xFF & cv.waitKey(1)
         if ch == 27:
             break
         if ch == ord(' '):
             for i, img in enumerate(imgs):
                 fn = '%s/shot_%d_%03d.bmp' % (shotdir, i, shot_idx)
-                cv2.imwrite(fn, img)
+                cv.imwrite(fn, img)
                 print fn, 'saved'
             shot_idx += 1
-    cv2.destroyAllWindows()
+    cv.destroyAllWindows()