image-enhancement

What software would you recommend for image enhancement prior to OCR (Optical Character Recognition)?

We are currently researching ways of enhancing image quality prior to submission to OCR. The OCR engine we are currently utilizing is the Scansoft API from Nuance (v15). We were researching the Lead Tools but have since decided to look elsewhere. The licensing costs associated with Lead Tools is just too great. To start with we are l...

uneven illuminated images

How to get rid of uneven illumination from images, that contain text data, usually printed but may be handwritten? It can have some spots of lights because the light reflected while making picture. I've seen the Halcon program's segment_characters function that is doing this work perfectly, but it is not open source. I wish to convert a...

What is a good way of Enhancing contrast of color images?

I split color image for 3 channels and made a contrast enhancement of each channel. Then merged them together, I like the image at the result, but it has different colors. Black objects became yellow and so on... EDIT: The algorithm I used is to calculate the 5th percentile and the 95th percentile as min and max values, and then expan...

Imagemagick or similar for scripted image enhancement

I found the following algorithm to work fairly well for enhancement of various images of whiteboards, etc: duplicate the layer, make sure the top layer is active (gaussian)blur the new layer. You shouldn't be able to read the text anymore. set the layer mode to dodge invert the layer I tried it out in gimp and it looks promising. I'...