Scan documents may have imperfections, such as black dots or lines, that result in the eDiscovery Bundle Processing Engine not being able to OCR the text behind them. Also previewing the documents in Legal Review or producing them in Legal Production will strip the scan imperfections along with the text behind those. In this case information that could have been visible in Legal Review or the produced images may be stripped from the visual representation of the document.
Processing Engine stripping scan imperfections.
Upgrade to eDiscovery Bundle 3.6.
In eDiscovery Bundle 3.6 we have introduced an advanced option thorugh which you can select the Processing Engine to use. Also we have introduced a more robust Processing Engine. The new Processing Engine will still not be able to read the text behind the scan imperfection, but it will not strip it from the visual representation of the document.