said by DracoFelis :

. . FFDshow has some truly powerful "filters" built into it. So any player setup to use FFDshow (don't forget to configure FFDshow to post-process the "RAW" video types, after other CODECs do their job), will automatically get access to the FFDShow "filters" for cleaning up video/audio issues in the source material WHILE YOU ARE WATCHING THE MATERIAL (i.e. this cleanup is "on the fly" as it were). Now you don't want to get carried away with FFDShow filter usage, or you will max out your CPU and kill your video (for example, I often just use the FFDShow "PostProcessing" filter to do some artifact cleanup, and occasionally use "Resize & Aspect" to "upsample" the source, and leave the other video filters off). But carefully used, those filters are truly amazing as to how much they can clean up video (and to a lessor degree clean up audio) WHILE YOU ARE WATCHING the source material!