kasslloyd wrote: daniel_reetz wrote:
Why do we need a grid? Right now I am thinking two lines are enough.
Re: IR cameras, yep, I'm familiar
But I don't want to be using IR because we'll likely be infringing on Google's patent, and that's not going to help us stay in business.
I'm not yet worried about the line quality at all. We can improve it somewhat with a baffle and/or pinhole. But I'll order a couple of red line generators anyway. Even if it is fuzzy, we can threshold it or use that information to produce a better line (it will get wider as the angle gets more oblique).
Google's patents probably mostly pertain to the software/math side, do you know what the patent #'s are? Even still staying away from IR will reduce costs, imo. So thats another benefit. IR just allows you to go faster since you can shoot one picture.
I wonder if you can get a glass filter that blocks everything but the nm range of the laser light, and a filter that blocks the laser light only... then you could basically do what google does without IR, project the laser light continuously and take both pictures at once. That would dramatically increase costs though for those filters.. heh.
I'm personally for doing it with minimal amount of pre-processing of the images as possible... but writing the software to accept everything from poor quality lines that have lots of bleed light and not positioned 100% accurately to perfect grids would be good.
as for the grids... I donno much about the algorithms involved so I can't say.. I just know that sensing depth usualy involves grids, like the Kinect sensor and google's dewarping tech both use grids... the work being done on the software for the scannable checkerboard to dewarp the page...
My thoughts is if you project a checkerboard pattern, a grid, the same algoritms that is used in that software might work?
It really boils down to the software, do we have an idea how to create it?
I found this on Google's Scanning Technology:http://www.patentgenius.com/patent/7508978.htmlhttp://www.freepatentsonline.com/7508978.pdfhttp://www.npr.org/blogs/library/2009/0 ... 08978.html
I was feeling bad for that Assistant Professor, Yoshihiro Watanabe, working for Professor Masatoshi Ishikawa at the Ishikawa Komuro Laboratory in the University of Tokyo, and assumed this to be an example where the small time inventor gets squashed by the corporate giants (he's the one who made this: http://www.youtube.com/watch?v=tCOXC5PTJj8
) But look at the dates.
The Tokyo video is done in March 17, 2010 and the Google Patient was applied for in March 24, 2009. So, I have to assume the Tokyo version is different and that they hope that it will someday be better,faster, and/or cheaper than Google's version?
As a side note to this: one day, when CDC cameras get better and better, one way to flip the pages faster is to allow for more excessively radical angles on the pages to be scanned rather than having them open wide for a moment in time. I would think that a imaging capable parabolic concentrator would be the ticket because it would allow light in from extreme angles while still allowing the image to be converted (as apposed to a compound parabolic concentrator CPC, which is a non-imaging lens due to being to extreme: http://en.wikipedia.org/wiki/File:Non-imaging_Compound_Parabolic_Concentrator_and_Parabolic_Concentrator.png
) The only way to get the light shot into the book pages turning so fast and so narrow would then require lighting from all angles concentrated onto the book--this is how a doctor is able to operate on a patient and see--the operating table lights provide a shadowless environment because the light is focused in from a very broad range of angles. I used to work for a medical manufacturer years ago and we made operating table lights. Some less know information about them happens to work here on the scanners too. First of all, notice they all have those rounded prisms, so it's very similar to the Fresnel lens, but I think that the different between an operating light and a true Fresnel lens is that a Fresnel is an imaging lens but the operating table lights make their prisms way way more pronounced and they do this for a reason. Imagine a long narrow prism--now bend it into a circle; now do this again and again with smaller and smaller circles. Now design these prisms so they behave very similar to the Fresnel len design, but they are also very much independent prisms--but these prisms are designed at just the right angles to provide perfectly pure white light--an intense white light that is void of all infrared light and ultra-violet. This would certainly be good for books--you get massive bright white light without the heat focused on the book.
One other side note about the operating table lights--it's actually very important that the lights are pure white and void of infrared and ultraviolet and shadowless: first of all the doctor is working with a tiny hole cut into someone--so the beam is able to light up more inside the hole than you would imagine from a tiny hole simply because it's focused into the hole, and since it comes from wide angles, it's shadowless even with their hands and surgical instruments in there; when a doctor is trying to figure out if something is a certain shade of blue, red or purple... you want the light to be pure white, so color is important to the surgeon; and lastly, when you are focusing all this huge volume of light into a hole, if you did not filter out the UV and IR you could cause some serious problems--especially with the IR. Even raising the temperature of the skin by a couple degrees makes the incision scare more. Hope that I didn't put folks to sleep. Hehehe