OpenCV - Removal of noise in image

Question

I have an image here with a table.. In the column on the right the background is filled with noise

How to detect the areas with noise? I only want to apply some kind of

Answer 1

I would go with median blur (probably 5*5 kernel).

if you are planning to apply OCR the image. I would advise you to the following:

1. Filter the image using Median Filter.
2. Find contours in the filtered image, you will get only text contours (Call them F).
3. Find contours in the original image (Call them O).
4. isolate all contours in O that have intersection with any contour in F.

Faster solution:

1. Find contours in the original image.
2. Filter them based on size.