I noticed, while fishing through some random F1 documents, that Suzuka Circuit were using a new logo and after checking their website it seems like they are indeed in the middle of a corporate re-branding. Being the nice guy I am I figured this new logo may be useful to someone so I managed to find a PDF document that had a vector version of the logo and not just a rasterised image. As is often the case with PDF documents from Suzuka circuit the PDF was password protected so couldn't be directly opened in an editor but no problem, I have a crafty method for side-stepping that, only something strange was going on...
Every time I tried to strip away the password protection, and opened the file in an editor, I just got a JPG version of the document?! What the hell! What is this voodoo? Has some clever sausage finally figured out a way to halt people like me in their tracks? Had my reign of vector extraction terror come to an end?? I was about to do something I am loathe to do and give up when I noticed something curious... moving the mouse over the document in the editor revealed the existence of some vector anchor points but they were offset enough from the positions of what I actually wanted to look like they were just remnants of a failed conversion attempt. They were further masked, as I later realised, by the fact that they were in assorted clipping groups so weren't directly clickable and thus their actual outlines didn't immediately reveal themselves.
Curiosity piqued I started realeasing all the groups, clipping groups, compound paths and voila, the devilishly devious method of trying to frustrate the likes of me revealed itself...
It would seem that someone, somewhere, has figured out that if they embed an exact JPG image of the vector data within the file then, if someone tries to strip out the password protection, this JPG gets pushed to the front and all the vector data, in its nice little outline hiding clipping groups, gets masked by it. To the casual observer this would be enough to put them off investigating further. Add in the fact that even though anchor points are still revealed by moving the cursor over the document they are offset enough to not actually look directly related to what it is you're after. Coupled with the clipping groups (so the outlines aren't immediately obvious) it all looks quite convincingly like something had gone wrong with password side-stepping conversion. And it so
very nearly fooled me!
This may all be part of the PDF spec, to attempt to thwart the casual vector snatcher, but if it isn't then I tip my cap to whoever came up with this method. Clever, but not clever enough though.