Extracted image colours inverted

[SThomas]

I have an application that extracts black and white scanned images of index cards that are white with black text from a number pdf documents. I have used the demo app as a template to do this and use the function ExtractImages to get the image before saving them.

Most of the generated images match the pdf, but in a number of the pdf's, where the scanned card image has a wide black border around it, the colours are reversed, so I get white text on a black background, which is difficult to read.


Is there any way of preventing this from happening. I have attached a screen print of one of the pdf files and one of the generated image files.

Thanks

[burning.liu]

Dear SThomas,

Thanks for your inquiry.

To help us reproduce this issue, please upload the sample pdf document and code snippet to our forum, or you can send them to [email protected]

Thank you.