I am experimenting with data deduplication under Server 2012. A question I have, for which I have found no answer: What happens in a situation with identically named files that are for example an identical image, but at different resolutions? Is there any part of these files that is the same, bit-for-bit, chunk-for-chunk or because they have different resolution, is every bit of each one spared? Example: if I have three directories, each named the same, and each containing a psd file with the same name but there is a 72 dpi, a 300 dpi and a 1200 dpi version respectively, does any part of these images remain the same and therefore gets replaced with only a reference? If it were to delete any of the three entirely how would I know it didn't delete the best (highest-resolution) version and keep the crappy one?
identically named files that are for example an identical image, but at different resolutions?
While these files all share the same name, they are not the same file. The binary that makes up the file is going to be different across these these files.
The "chunks" of data that can be deduplicated are not going to be shared by these files that are saved at different resolutions.
You could experiment with this just to satisfy yourself. Find a picture you know the size and dpi and make a copy of it - only experiment with the copy.
Use your photo editing software to change the dpi and then save that altered image in the same folder as the copied photo under a different name. Now compare the two files for differences.
BigPaw: I did that and have been watching to see. Nothing has changed with the test files for over a week so this backs up JorgeM's message. I wanted to get someone else's opinionh before I assumed I knew it was no changing them in this test scenario.
I think I am safe with regard to the concern of "better" files being chopped up for parts of "not-good" versions. I would only have file replacement if, for example, I had two identical files of same name/resolution, etc.
Thanks to you both!
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