Using dicom Images with OpenCV in Python

Question

I am trying to use a dicom image and manipulate it using OpenCV in a Python environment. So far I have used the pydicom library to read the dicom(.dcm) image data and using the pixel array attribute to display the picture using OpenCV imshow method. But the output is just a blank window. Here is the snippet of code I am using at this moment.

import numpy as np
import cv2
import pydicom as dicom

ds=dicom.dcmread('sample.dcm')
cv2.imshow('sample image dicom',ds.pixel_array)

cv2.waitkey()

If i print out the array which is used here, the output is different from what i would get with a normal numpy array. I have tried using matplotlib imshow method as well and it was able to display the image with some colour distortions. Is there a way to convert the array into a legible format for OpenCV?

Answer 1

Faced a similar issue. Used exposure.equalize_adapthist() (source). The resulting image isn't a hundred percent to that you would see using a DICOM Viewer but it's the best I was able to get.

import numpy as np
import cv2
import pydicom as dicom
from skimage import exposure

ds=dicom.dcmread('sample.dcm')
dcm_sample=ds.pixel_array
dcm_sample=exposure.equalize_adapthist(dcm_sample)
cv2.imshow('sample image dicom',dcm_sample)

cv2.waitkey()