OpenCV 3.0 LineIterator

Question

I want to use the LineIterator in OpenCV 3.0 using Python, is it still available with OpenCV 3.0 built for Python? It seems that the answers on the internet are all pointing to cv.InitLineIterator which is part of the cv module. I've tried importing this module but it seems like it is not included with the current build. Has it been renamed or strictly just removed?

Answer 1

I've solved my own problem. Line iterator seems to be unavailable in the cv2 library. Therefore, I made my own line iterator. No loops are used, so it should be pretty fast. Here is the code if anybody needs it:

def createLineIterator(P1, P2, img):     """     Produces and array that consists of the coordinates and intensities of each pixel in a line between two points      Parameters:         -P1: a numpy array that consists of the coordinate of the first point (x,y)         -P2: a numpy array that consists of the coordinate of the second point (x,y)         -img: the image being processed      Returns:         -it: a numpy array that consists of the coordinates and intensities of each pixel in the radii (shape: [numPixels, 3], row = [x,y,intensity])          """    #define local variables for readability    imageH = img.shape[0]    imageW = img.shape[1]    P1X = P1[0]    P1Y = P1[1]    P2X = P2[0]    P2Y = P2[1]     #difference and absolute difference between points    #used to calculate slope and relative location between points    dX = P2X - P1X    dY = P2Y - P1Y    dXa = np.abs(dX)    dYa = np.abs(dY)     #predefine numpy array for output based on distance between points    itbuffer = np.empty(shape=(np.maximum(dYa,dXa),3),dtype=np.float32)    itbuffer.fill(np.nan)     #Obtain coordinates along the line using a form of Bresenham's algorithm    negY = P1Y > P2Y    negX = P1X > P2X    if P1X == P2X: #vertical line segment        itbuffer[:,0] = P1X        if negY:            itbuffer[:,1] = np.arange(P1Y - 1,P1Y - dYa - 1,-1)        else:            itbuffer[:,1] = np.arange(P1Y+1,P1Y+dYa+1)                  elif P1Y == P2Y: #horizontal line segment        itbuffer[:,1] = P1Y        if negX:            itbuffer[:,0] = np.arange(P1X-1,P1X-dXa-1,-1)        else:            itbuffer[:,0] = np.arange(P1X+1,P1X+dXa+1)    else: #diagonal line segment        steepSlope = dYa > dXa        if steepSlope:            slope = dX.astype(np.float32)/dY.astype(np.float32)            if negY:                itbuffer[:,1] = np.arange(P1Y-1,P1Y-dYa-1,-1)            else:                itbuffer[:,1] = np.arange(P1Y+1,P1Y+dYa+1)            itbuffer[:,0] = (slope*(itbuffer[:,1]-P1Y)).astype(np.int) + P1X        else:            slope = dY.astype(np.float32)/dX.astype(np.float32)            if negX:                itbuffer[:,0] = np.arange(P1X-1,P1X-dXa-1,-1)            else:                itbuffer[:,0] = np.arange(P1X+1,P1X+dXa+1)            itbuffer[:,1] = (slope*(itbuffer[:,0]-P1X)).astype(np.int) + P1Y     #Remove points outside of image    colX = itbuffer[:,0]    colY = itbuffer[:,1]    itbuffer = itbuffer[(colX >= 0) & (colY >=0) & (colX<imageW) & (colY<imageH)]     #Get intensities from img ndarray    itbuffer[:,2] = img[itbuffer[:,1].astype(np.uint),itbuffer[:,0].astype(np.uint)]     return itbuffer