Im working with 128 x 128 arrays of type float32. These arrays are pulled from binary files and I'm attempting to locate disks in each array.

When I try to use the HoughCircles example code:

```
img = Image.fromarray(fa)
cimg = cv2.cvtColor(img,cv2.COLOR_GRAY2BGR)

circles = cv2.HoughCircles(img,cv2.HOUGH_GRADIENT,1,20,param1=50,param2=30,minRadius=0,maxRadius=0)

circles = np.uint16(np.around(circles))
for i in circles[0,:]:
    # draw the outer circle
    cv2.circle(cimg,(i[0],i[1]),i[2],(0,255,0),2)
# draw the center of the circle
cv2.circle(cimg,(i[0],i[1]),2,(0,0,255),3)

```

I recieve the following error:

> 
> File "", line 2, in 
>  cimg = cv2.cvtColor(img,cv2.COLOR\_GRAY2BGR)
> 
> 
> TypeError: src is not a numpy array, neither a scalar
> 
> 
> 

If I don't convert to image with Image.fromarray, I recieve the following error indicating that I still am not working with the correct type.

> 
> File "", line 1, in 
>  circles = cv2.HoughCircles(fa,cv2.HOUGH\_GRADIENT,1,20,param1=50,param2=30,minRadius=0,maxRadius=0)
> 
> 
> error: OpenCV(3.4.4)
>  /Users/travis/build/skvark/opencv-python/opencv/modules/imgproc/src/hough.cpp:1736:
>  error: (-215:Assertion failed) !\_image.empty() && \_image.type() ==
>  CV\_8UC1 && (\_image.isMat() || \_image.isUMat()) in function
>  'HoughCircles'
> 
> 
>