Because there is no such tool available that we have written one. You can download the i-net PDF content comparer and use it. I hope that help other with the same problem. If you have problems with it or you have feedback for us then you can contact our support. The advantage of this tool is, that it's neither a pure text comparer nor an image comparer. It compares by structure, checks if the containing elements are "the same" - so your compared PDFs do not have to match 100% but be within a definable similarity. And it's for free. I'd recommend this too! It crashed on a document so I sent it to them. T fixed it! .D I feel great. It can generate images with differences or it can give you a textual report in the console. Refrence. Stack Overflow
And GitHub Issues.