i am not sure which one is best open source comparison tools. as of now, i would like to go with apache tika 1.4 to convert from doc to txt file format.
this will be very helpful to achieve my intention. my suggestion is, please add this comparison feature in openkm . i did something for my goal in openkm application.
"Added checkboxes for each version and one "Comparison" button at column header under history tab. if user clicked on comparison button, after selecting two checkbox, should be shown the result side by side view with highlighting diff." i did only for text format only. attached screen shot , what i have done ...
Attachments
selecting two checkboxes. selecting_checkbox.png (113.38 KiB) Viewed 3945 times
after clicking on compare button result_for_plain-text.png (97.58 KiB) Viewed 3945 times