Slashdot Mirror
How Google's High Speed Book Scanner De-Warps Pages
Hugh Pickens writes "Patent 7,508,978, awarded to Google, shows how the company has already managed to scan more than 7 million books. Google's system uses two cameras and infrared light to automatically correct for the curvature of pages in a book. By constructing a 3D model of each page and then 'de-warping' it afterward, Google can present flat-looking pages online without having to slice books up or mash them onto a flatbed scanner. Stephen Shankland writes that the 'sophistication of the technology illustrates that would-be competitors who want to feature their own digitized libraries won't have a trivial time catching up to Google.' First, a book is placed on a flat surface, while above it, an infrared projector displays a special mazelike pattern onto the pages. Next, two infrared cameras photograph the infrared pattern from different perspectives. 'The images can be stereoscopically combined, using known stereoscopic techniques, to obtain a three-dimensional mapping of the pattern,' according to the patent. 'The pattern falls on the surface of (the) book, causing the three-dimensional mapping of the pattern to correspond to the three-dimensional surface of the page of the book.'"
Wasn't this a Sci-Fi movie staple back in the 80s? They used it for body and object scanning, not books...but still.
but to be honest this is at least worthy patent
-- if you mod me down, I will become more powerful than you can possibly imagine
The technique is old, many years old. What is google's patent for? The use of a decades-old technique ON BOOKS?
Maybe those books are less important to commit to a digital scan ;-)
they could probably do it in the visible spectrum as well, it would just take twice as long because they can't map and scan at the same time.
Failing that there are alternative methods that might work as well.
Collector's Edition
Ok, is it just me, but wouldn't it be easier to just cut the spine off the book instead of developing a whole new way of scanning it?
With 7 million books, the manpower and time saved for them to cut the spine off would be worth it.
Also, they can resell the books if needed or give them charity after they are done.
Kind of would be a waste of a paper to tear that many books apart.
"I am the king of the Romans, and am superior to rules of grammar!"
-Sigismund, Holy Roman Emperor (1368-1437)
Bell Labs did basic research that most of the time didn't have any current commercial applications and maybe never will.
Google's all have current commercial applications. I don't know of anything they do that is for pure research and to add to humanities knowledge.
I don't see why this is such a showstopper for other book scanning projects. Right off the top of my head I can think of three methods of dewarping book scans that have nothing do to with Google's methods. While Google's method is definitely quite interesting and seems like a great solution, it is by no means whatsoever the only way of accomplishing this.
This may be a projector thing, but they are doing something of physical manipulation. It would be pretty much appropriate to be patented. The whole thing is physically transformative. Meanwhile, if someone made their own version using something different, it too, would be patentable/improvement patent, which is how the patent system is supposed to work.
To be clear, I'm saying the system as a whole should be patentable (infrared), but not the software used to decode it.
This is useful and interesting, but doesn't seem particularly novel.
Projecting a known pattern onto a surface or using multiple cameras to determine the shape of a surface have been around for quite a while, so adding it to an OCR system doesn't seem like a big deal.
I really don't think the libraries that Google was scanning at would have appreciated that too much..
I almost feel bad. I know what a radon transform is and I've taken a class on inverse problems.
My point was just that the common view of what is mathematics is rather anemic and quick to give engineering credit to relatively simple ideas. I suspect that the patent office has similar fallacious thinking.
"They were pure niggers." – Noam Chomsky