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Ask Slashdot: Best Webcam To Augment Impaired Vision?
mynamestolen writes "In order to read paper-based books many visually impaired people want to attach a webcam to a computer and attach the computer to a TV. Some Electronic Magnifiers are purpose-built to provide a similar solution. Different organisations around the world (such as in the UK) have help pages. But I have not been able to find a guide to set up my own system. So I'm asking Slashdot readers how to go about it. What is the best camera to use if I want to hold the camera in my hand and point it at book or magazine? What parameters should I adjust, either in the software or on the camera? Depth of view, refresh rates, contrast, color balance and resolution might be key problems. My system is Linux and getting drivers for a good camera might also be a problem."
Because now, you can see EVERYTHING. ;-)
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Never been known to fail..."
I know next to nothing about cameras, etc. However, I'd suggest you go look at the specs for some e-readers, if you can find them. I'd figure the design people for Amazon, B&N, or whoever else already did the homework on refresh rate, color balance, etc. to ensure readability.
Everything is better with chainsaws.
I use a mix of platforms but for Windows where things are especially bad, I use a Logitech C610 (with and without a stand) combined with a product called ZoomText (version 10 has built-in CCTV functionality now).
It might be easier to set up a little copy stand/tripod rig. Lay the book down, lock in the focus, and all you need to do is flip the pages.
Instead of hacking together your own solution, look for non-certified ones online. My grandmother got one for $20-30, i don't remember how much exactly, that she can use in the reading stand that was included or use with her hand (which, unless you have really steady hands, is a bad idea). It is fully adjustable in terms of DoF, zoom, etc. and can even invert colors with the flip of a switch. The real bonus is that it attaches directly to either the TV or the computer. Its so easy, she even takes it to other people's homes.
Another piece of advice, try to have an HD screen that has a proper white and black level and good contrast. According to her, it makes a world of difference compared to her old tv that was 30 years old..
Machines have been around for ages that you can use to read a book on a large screen with different levels of magnification, it has a tray that you can move around easily and it has a small CCD camera hooked up to a TV screen.
When I was in school in the 80s I used a VisualTech CCD magnifier, in fact they're still around: http://www.visual-techconnection.com/cctvs1.htm
However since most of us have computers these days it's hard to justify having such a bulky device around for books.
So what are the options:
1. Get eBooks and zoom in to your hearts content
(problem: not all books are available in eBook form)
2. Get large print copy of the book you want to read
(problem: same as above, enlargement might be impractical or unavailable [your library mileage may vary])
3. Get a stand alone magnifier device for yer book readin'
(compatible with most books and sidesteps copyright issues)
I can see how people think that computer + webcam + tray = book reader, so I'm interested to see if anyone out there in candyland has found a good setup for this.
But yes, this is a thing that visually impaired people have to deal with that so far only seems to have been solved by a handful of companies.
crazy dynamite monkey
My grandma used big, huge magnifying glasses.
Are we hitting some kind of magnifying barrier or why the Rube-Goldberg solution?
It's propably easier on the ants, tho.
20 minutes into the future
I'm mystified why it has to be a webcam, other than the joy of complexity.
I am personally involved in two "scenes" where other participants a couple decades grayer than myself need similar tech and both use plain ole cameras hooked up to TVs.
I can easily solder 0402 SMD by hand (I kid you not, and I've assembled working N5AC microwave oscillator kits to prove it.. the main vco inductor is a 0402 as are a bunch of the bypass caps. Also I know several model machinists (of the homemade steam engine variety) who use toolpost mounted microscopes to see little stuff, also some of them are pretty young, like the guys trying to machine a research medical adapter between a hypo needle and some medical research "thing".
Anyway the killer for hand/eye coordination is latency. A simple camcorder is fast enough, a webcam no freaking way. Also the "boot time" of a camcorder is faster than any PC, not to mention "application launch". No software updates, no viruses (other than the ones you're looking at under the microscope LOL).
I do know that one huge user of "webcam glued to gear" is medical examiners / pathologists because its easier to import CSI style evidence into a report edited on a computer if you use a webcam. Otherwise stay away from webcams !
"Science flies us to the moon. Religion flies us into buildings." - Victor Stenger
RTFQ much?
He asks a question about "In order to read paper-based books" and you babble about how easy it is to install a second video card into his book (a book which is also apparently running Windows)!
The camera makes little difference for still program material. Color balance is typically handled automatically, but can always be adjusted.
I would say that you are focusing on the wrong aspect of your system - coming up with a good stand is probably going to affect usability much ore an the camera. I would suggest starting with a nice copy stand and maybe going from there.
Software with a "steady cam" feature is a good. It will remove jitter that will occur from holding the camera with your hand.
Webcams are often pretty poor quality. The main factor in cameras is the sensor size (not MP, but physical size - a big sensor captures more light). But a good sensor is more expensive, and heavy. And it's not fun trying to figure out webcam specs, as they are often simply not well publicised.
The first step - get good lighting. A bad camera with good lighting is better than a good camera with bad lighting. Unless you have something as powerful as a high-end DSLR, you simply need good lighting.
If you have good lighting, you can shoot at a lower ISO, which means less noise. You can shoot at a higher speed, which means a faster refresh (unless there's a bottleneck somewhere else - probably USB speed) and less blur. You can get a higher depth of field, even up close, so you don't have to focus. There's a reason why professional photographers, working with the best cameras money can buy, spend so much time setting up lots of lighting - most cameras are simply not at their best in low light.
My in-laws have severe macular degeneration to the point that they gave up driving, and my mother-in-law loves to read, and we ended up buying a technician's visor with four magnifier lenses for her, and she's able to read paperback books with it. They had looked up expensive devices (one of the biggest vision-assistance companies is in the greater Boston area and they even went to the showroom) but found that this fairly simple optical solution worked best.
Do not look into laser with remaining eye.
getting a webcam which implements the UVC (USB Video device Class)
Agreed. I was going to recommend a high-res Logitech that I have but it's not currently made. However their C920 has a tripod mount (finally!) is well-reviewed and has a higher resolution with the reviewers talking about the stability of the autofocus on extreme close-ups, so I'd probably buy this one with a heavy wide-base tripod (like this if I were going to try to do this kind of build. A clip-on light with a gooseneck will probably make things look better too.
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OUTSIDE_IP=$(dig +short my.ip @outsideip.net)
An Android device with a large screen and support for MHL would be ideal. It would be highly portable, given the widespread use of HDMI all you need is an adapter, and the cameras provided with most modern tablets/phones are as good (if not better) then most webcam solutions.
My system is Linux
I take it you didn't see this part of it, or just chose to ignore it...
My system is Linux
Did you not see I admitted to skimming the original post? Is it that you "can't read", or maybe you just skim a bit too much all the while failing to make any real contribution whatsoever. When suggesting the magnification software I also said "or any other OS with a built in magnifier". No... didn't see that? In fact everything I said translates to Linux, FreeBSD or OSX. To be more specific then the generalized, actually platform independent, response I gave would really just be advocacy of particular products. Perhaps you are too inexperienced to realize this fact. I could be wrong... maybe you'll now surprise us with a superior suggestion to my own that would actually be useful to OP. I hope you'll excuse me if I forgo holding my breath in anticipation.
Never the less, thanks AC, your post was as enlightening as usual!
To those interested, the Ubuntu workstation I do my development on didn't seem to have a magnifier installed by default, but I'm sure I could apt-get something on the following list if needed:
http://www.magnifiers.org/links/Screen_Magnifiers/UNIX_Linux/
Get a Camcorder and hook it up to their TV. Seriously, it's that simple, Get a camcorder with HDMI out, mount it on a tripod, and run and HDMI cord under the rug. No software needed. $300 for a camcorder and $40 for a tripod, $30 for a long HDMI cable. The camcorder has the light built in.
I'll second this, with the caveat that you don't need the newest, most expensive stuff to make it work - I've achieved perfectly usable results with nothing more than a $50 hi-8 camcorder and component cables (televisions do still have component hookups, right?).
An enigma, wrapped in a riddle, shrouded in bacon and cheese
Last year I set up a facial recogintion system. It needed to be able see faces in crowd clear enough to determine age and gender. While this is a different requirement from what you need it did share three features. It ran on Linux, used a webcam, and needed high quality. The recommend cameras, which we used succesfully, were the Logitech HD series. While not a cheap camera I think they are still reasonably priced, do a good job and work with Linux (Cent OS in our case).
You may already have a digital camera (still or camcorder)with video or hdmi out which you can plug into a TV or monitor. These have the advantage of zoom and autofocus and often have a power input for continuous use. It's steadier and less tiring to use a tripod or copy stand. For camcorders, see the thread at http://www.avsforum.com/t/1302280/low-cost-cam-with-live-hdmi-pass-through Another choice is to get some strong binocular loupe glasses from China via ebay. They come in a variety of strengths and you can examine or read by moving the material in front of you. They are cheap ($1-50) and portable. Some come with their own LED illuminators. Search for binocular loupe
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My Dad has degenerating eyes (only one eye works) but he says if he couldn't read spy novels he doesn't know what he'd do. He is not into technology. He uses a simple hand-held magnifying glass to read large-print novels from the library. We got him a hand-held one with big lens and LED but the brightness startled him (he's in his 80s) and the magnification was inappropriate, or something, can't use it. Though we'll try again maybe. Assistive tools (we've also been trying a new cheap hearing aid but not sure if that's going to work...) are not easy, and not welcomed always by aged people... in other words you could invest money to make a system and find out he/she prefers not to use it.
We have a huge screen tv which he can't use, the contrast ratio is not high enough for him to see ordinary tv. I don't have high hopes for him using that with a hand-held camera.
I can imagine a 10" android tablet with an extremely light-weight wireless camera, I don't know if there is a high enough resolution one with an android phone that could work.. that would also give him something to call for help if he fell or something.
I had an idea to research a diy book reader like what already exists with a big screen and a camera, and things that hold pages down, but maybe getting a really large tablet and using e-books is the best. The big print books from the library are hard-cover thousands of pages monstrosities!
If you have any ideas let me know. The obvious answer is not always the best.
I know it doesn't fit the 'hand held' part of the requirements, but in education there's a tool designed for viewing printed documents on a projector.
SMART does a document camera which has a built in stand to hold it over the text, an LED light to help in low light conditions, and will output to VGA or DVI/HDMI directly with no need for a computer, so you can just plug straight into a modern TV or any computer monitor. It also can act as a USB webcam as well.
It does wonderful resolution (720p isn't bad for what is basically a webcam) - the only downside is the price: £450 - there are cheaper alternitives by other brands but they lack the image quality and often the direct VGA outputs.