How can I remove aliasing in an image without introducing blur? I am trying to reduce aliasing in an image using some filters. I tried the Gaussian variant of filters to remove the said high frequency patterns in the image, but I feel it's a bit too much of a blur. 

I need a filter that can help me do some kind of anti-aliasing without doing too much blur. 

I have searched a lot and unfortunately the results are not fruitful.
Depending on the specific content of your input images, you could either use the Gaussian filter with kernel size varying with distance from the camera ( Link ) or use a slightly more complex bilateral filter, which is widely used to eliminate noise while keeping edges mostly intact.