Submitted by brad on Sun, 2017-04-23 13:25.
Not everybody loves video calls, but there are times when they are great. I like them with family, and I try to insist on them when negotiating, because body language is important. So I’ve watched as we’ve increased the quality and ease of use.
The ultimate goals would be “retinal” resolution — where the resolution surpasses your eye — along with high dynamic range, stereo, light field, telepresence mobility and VR/AR with headset image removal. Eventually we’ll be able to make a video call or telepresence experience so good it’s a little hard to tell from actually being there. This will affect how much we fly for business meetings, travel inside towns, life for bedridden and low mobility people and more.
Here’s a proposal for how to provide that very high or retinal resolution without needing hundreds of megabits of high quality bandwidth.
Many people have observed that the human eye is high resolution on in the center of attention, known as the fovea centralis. If you make a display that’s sharp where a person is looking, and blurry out at the edges, the eye won’t notice — until of course it quickly moves to another section of the image and the brain will show you the tunnel vision.
Decades ago, people designing flight simulators combined “gaze tracking,” where you spot in real time where a person is looking with the foveal concept so that the simulator only rendered the scene in high resolution where the pilot’s eyes were. In those days in particular, rendering a whole immersive scene at high resolution wasn’t possible. Even today it’s a bit expensive. The trick is you have to be fast — when the eye darts to a new location, you have to render it at high-res within milliseconds, or we notice. Of course, to an outside viewer, such a system looks crazy, and with today’s technology, it’s still challenging to make it work.
With a video call, it’s even more challenging. If a person moves their eyes (or in AR/VR their head) and you need to get a high resolution stream of the new point of attention, it can take a long time — perhaps hundreds of milliseconds — to send that signal to the remote camera, have it adjust the feed, and then get that new feed back to you. There is no way the user will not see their new target as blurry for way too long. While it would still be workable, it will not be comfortable or seem real. For VR video conferencing it’s even an issue for people turning their head. For now, to get a high resolution remote VR experience would require sending probably a half-sphere of full resolution video. The delay is probably tolerable if the person wants to turn their head enough to look behind them.
One opposite approach being taken for low bandwidth video is the use of “avatars” — animated cartoons of the other speaker which are driven by motion capture on the other end. You’ve seen characters in movies like Sméagol, the blue Na’vi of the movie Avatar and perhaps the young Jeff Bridges (acted by old Jeff Bridges) in Tron: Legacy. Cartoon avatars are preferred because of what we call the Uncanny Valley — people notice flaws in attempts at total realism and just ignore them in cartoonish renderings. But we are now able to do moderately decent realistic renderings, and this is slowly improving.
My thought is to combine foveal video with animated avatars for brief moments after saccades and then gently blend them towards the true image when it arrives. Here’s how.
- The remote camera will send video with increasing resolution towards the foveal attention point. It will also be scanning the entire scene and making a capture of all motion of the face and body, probably with the use of 3D scanning techniques like time-of-flight or structured light. It will also be, in background bandwidth, updating the static model of the people in the scene and the room.
- Upon a saccade, the viewer’s display will immediately (within milliseconds) combine the blurry image of the new target with the motion capture data, along with the face model data received, and render a generated view of the new target. It will transmit the new target to the remote.
- The remote, when receiving the new target, will now switch the primary video stream to a foveal density video of it.
- When the new video stream starts arriving, the viewer’s display will attempt to blend them, creating a plausible transition between the rendered scene and the real scene, gradually correcting any differences between them until the video is 100% real
- In addition, both systems will be making predictions about what the likely target of next attention is. We tend to focus our eyes on certain places, notably the mouth and eyes, so there are some places that are more likely to be looked at next. Some portion of the spare bandwidth would be allocated to also sending those at higher resolution — either full resolution if possible, or with better resolution to improve the quality of the animated rendering.
The animated rendering will, today, both be slightly wrong, and also suffer from the uncanny valley problem. My hope is that if this is short lived enough, it will be less noticeable, or not be that bothersome. It will be possible to trade off how long it takes to blend the generated video over to the real video. The longer you take, the less jarring any error correction will be, but the longer the image is “uncanny.”
While there are 100 million photoreceptors in the whole eye, but only about a million nerve fibers going out. It would still be expensive to deliver this full resolution in the attention spot and most likely next spots, but it’s much less bandwidth than sending the whole scene. Even if full resolution is not delivered, much better resolution can be offered.
Stereo and simulated 3D
You can also do this in stereo to provide 3D. Another interesting approach was done at CMU called pseudo 3D. I recommend you check out the video. This system captures the background and moves the flat head against it as the viewer moves their head. The result looks surprisingly good. read more »
Submitted by brad on Mon, 2017-02-20 15:15.
I have so much paper that I’ve been on a slow quest to scan things. So I have high speed scanners and other tools, but it remains a great deal of work to get it done, especially reliably enough that you would throw away the scanned papers. I have done around 10 posts on digitizing and gathered them under that tag.
Recently, I was asked by a friend who could not figure out what to do with the papers of a deceased parent. Scanning them on your own or in scanning shops is time consuming and expensive, so a new thought came to me.
Set up a scanning table by mounting a camera that shoots 4K video looking down on the table. I have tripods that have an arm that extends out but there are many ways to mount it. Light the table brightly, and bring your papers. Then start the 4K video and start slapping the pages down (or pulling them off) as fast as you can.
There is no software today that can turn that video into a well scanned document. But there will be. Truth is, we could write it today, but nobody has. If you scan this way, you’re making the bet that somebody will. Even if nobody does, you can still go into the video and find any page and pull it out by hand, it will just be a lot of work, and you would only do this for single pages, not for whole documents. You are literally saving the document “for the future” because you are depending on future technology to easily extract it. read more »
Submitted by brad on Mon, 2016-12-19 11:06.
Everybody should have off-site backup of their files. For most people, the biggest threat is fire, but here in California, the most likely disaster you will encounter is an earthquake. Only a small fraction of houses will burn down, but everybody will experience the big earthquake that is sure to come in the next few decades. Of course, fortunately only a modest number of houses will collapse, but many computers will be knocked off desks or have things fall on them.
To deal with this, I’ve been keeping a copy of my data in my car — encrypted of course. I park in my driveway, so nothing will fall on the car in a quake, and only a very large fire would have risk of spreading to the car, though it’s certainly possible.
The two other options are network backup and truly remote backup. Network backup is great, but doesn’t work for people who have many terabytes of storage. I came back from my latest trip with 300gb of new photos, and that would take a very long time to upload if I wanted network storage. In addition, many TB of network storage is somewhat expensive. Truly remote storage is great, but the logistics of visiting it regularly, bringing back disks for update and then taking them back again is too much for household and small business backup. In fact, even being diligent about going down to the car to get out the disk and update is difficult.
A possible answer — a wireless backup box stored in the car. Today, there are many low-cost linux based NAS boxes and they mostly run on 12 volts. So you could easily make a box that goes into the car, plugs into power (many cars now have 12v jacks in the trunk or other access to that power) and wakes up every so often to see if it is on the home wifi, and triggers a backup sync, ideally in the night. read more »
Submitted by brad on Mon, 2015-02-16 16:26.
Back in 2008, I proposed the idea of a scanner club which would share high-end scanning equipment to rid of houses of the glut of paper. It’s a harder problem than it sounds. I bought a high-end Fujitsu office scanner (original price $5K, but I paid a lot less) and it’s done some things for me, but it’s still way too hard to use on general scanning problems.
I’ve bought a lot of scanners in the day. There are now lots of portable hand scanners that just scan to an SD card which I like. I also have several flatbeds and a couple of high volume sheetfeds.
In the scanner club article, I outlined a different design for how I would like a scanner to work. This design is faster and much less expensive and probably more reliable than all the other designs, yet 7 years later, nobody has built it.
The design is similar to the “document camera” family of scanners which feature a camera suspended over a flat surface, equipped with some LED lighting. Thanks to the progress in digital cameras, a fast, high resolution camera is now something you can get cheap. The $350 Hovercam Solo 8, which provides an 8 megapixel (4K) image at 30 frames per second. Soon, 4K cameras will become very cheap. You don’t need video at that resolution, and still cameras in the 20 megapixel range — which means 500 pixels/inch scanning of letter sized paper — are cheap and plentiful.
Under the camera you could put anything, but a surface of a distinct colour (like green screen) is a good idea. Anything but the same colour as your paper will do. To get extra fancy, the table could be perforated with small holes like an air hockey table, and have a small suction pump, so that paper put on it is instantly held flat, sticking slightly to the surface.
The real feature I want is an ability to scan pages as fast as a human being can slap them down on the table. To scan a document, you would just take pages and quickly put them down, one after the other, as fast as you can, so long as you pause long enough for your hand to leave the view and the paper to stay still for 100 milliseconds or so.
The system will be watching with a 60 frame per second standard HD video camera (these are very cheap today.) It will watch until a new page arrives and your hand leaves. Because it will have an image of the table or papers under the new sheet, it can spot the difference. It can also spot when the image becomes still for a few frames, and when it doesn’t have your hand in it. This would trigger a high resolution still image. The LEDs would flash with that still image, which is your signal to know the image has been taken and the system is ready to drop a new page on. Every so often you would clear the stack so it doesn’t grow too high.
Alternately, you could remove pages before you add a new one. This would be slower, you would get no movement of papers under the top page. If you had the suction table, each page would be held nice and flat, with a green background around it, for a highly accurate rotation and crop in the final image. With two hands it might not be much slower to pull pages out while adding new ones.
No button is pressed between scans or even to start and finish scanning. You might have some buttons on the scanner to indicate you are clearing the stack, or to select modes (colour, black and white, line art, double sided, exposure modes etc.) Instead of buttons, you could also have little tokens you put on the surface with codes that can be read by the camera. This can include sheets of paper you print with bar codes to insert in the middle of your scanning streams.
By warning the scanner, you could also scan bound books and pamplets and even stapled documents without unstapling. You will get some small distortions but the scans will be fine if the goal is document storage rather than publishing. (You can even eliminate those distortions if you use 3D scanning techniques like structured light projection onto the pages, or having 2 cameras for stereo.)
For books, this is already worked out, and many places like the Internet Archive build special scanners that use overhead cameras for books. They have not attacked the “loose pile of paper” problem that so many of us have in our files and boxes of paper.
Why this method?
I believe this method is much faster than even high speed commercial scanners on all but the most regular of documents. You can flip pages at better than 1 per second. With small things, like business cards and photos, you can lay down multiple pages per second. That’s already the speed of typical high end office scanners. But the difference is actually far greater.
For those office scanners, you tend to need a fairly regular stack or the document feeder may mess up. Scanning a pile of different sized pages is problematic, and even general loose pages run the risk of skipping pages or other errors. As such, you always do a little bit of prep with your stacks of documents before you put them in the scanner. No button scanning will work with a random pile of cards and papers, including even folded papers. You would unfold them as you scan, but the overall process will take less time.
A scanner like this can handle almost any size and shape of paper. It could offer the option to zoom the camera out or pull it higher to scan very large pages, which the other scanners just can’t do. A lower ppi number on the larger pages, but if you can’t handle that, scan at full ppi and stitch together like you would on an older scanner.
The scans will not be as clean as a flatbed or sheetfed scanner. There will be variations in lighting and shading from curvature of the pages, along with minor distortions unless you use the suction table for all pages. A regular scanner puts a light source right on the page and full 3-colour scanning elements right next to it, it’s going to be higher quality. For publication and professional archiving, the big scanners will still win. On the other hand, this scanner could handle 3-dimensional objects and any thickness of paper.
Another thing that’s slower here is double sided pages. A few options are available here:
- Flip every page. Have software in the scanner able to identify the act of flipping — especially easy if you have the 3D imaging with structured light.
- Run the whole stack through again, upside-down. Runs the risk of getting out of sync. You want to be sure you tie every page with its other side.
- Build a fancier double sided table where the surface is a sheet of glass or plexi, and there are cameras on both sides. (Flash the flash at two different times of course to avoid translucent paper.) Probably no holes in the glass for suction as those would show in the lower image.
Ideally, all of this would work without a computer, storing the images to a flash card. Fancier adjustments and OCR could be done later on the computer, as well as converting images to PDFs and breaking things up into different documents. Even better if it can work on batteries, and fold up for small storage. But frankly, I would be happy to have it always there, always on. Any paper I received in the mail would get a quick slap-down on the scanning table and the paper could go in the recycling right away.
You could also hire teens to go through your old filing cabinets and scan them. I believe this scanner design would be inexpensive, so there would be less need to share it.
As Moore’s law progresses, we can do even more. If we realize we’re taking video and have the power to process it, it becomes possible to combine all the video frames with a page in it, and produce an image that is better than any one frame, with sub-pixel resolution, and superior elimination of gradations in lighting and distortions.
As noted in the comments, it also becomes possible to do all this with what’s in a mobile phone, or any video camera with post-processing. One can even imagine:
- Flipping through a book at high speed in front of a high-speed camera, and getting an image of the entire book in just a few seconds. Yes, some pages will get missed so you just do it again until it says it has all the pages. Update: This lab did something like this.
- Vernor Vinge’s crazy scanner from Rainbow’s End, which sliced off the spines and blew the pages down a tube, being imaged all the way along to capture everything.
- Using a big table and a group of people who just slap things down on the table until the computer, using a projector, shows you which things have been scanned and can be replaced. Thousands of pages could go buy in minutes.
Submitted by brad on Thu, 2014-04-03 14:01.
Look at the skyline of any growing city, and what do you see, but a sea of construction cranes. The theory is that each crane will go away and be replaced by an architectually interesting or pleasing building, but the cycle continues and there are always cranes.
My proposal: An ordinance requiring aesthetic elements on construction cranes. Make them look beautiful. Make them look like the birds they are named after, or anything else. Get artists to design them as grand public art installations. Obviously you can’t increase the weight a lot, or cut the visibility of the operator too much, but leave that as a challenge to the artists. And give us a city topped with giant works of art instead of eyesores.
While we’re building these skyscrapers, it seems to me we also don’t seem to care about the aesthetics of our cities from above. The view from the towers, or incoming aircraft bringing in fresh visitors, is of ugly rooftops, covered with ugly pipes, giant air conditioners and spaces everybody imagines that nobody sees. Yet we all see them.
Compare that with many European hillside towns where everybody knew they would be seen from above. At least in the old days, the roofs were crafted with the same care as the house. Today, that’s been changing, and many roofs are covered with antennas, satellite dishes and in the middle east, black water heaters. We care a lot about how our houses look from the curb, and we imagine people don’t see the roof. But we do.
Submitted by brad on Wed, 2013-05-08 13:37.
You’ve probably noticed that with many of our portable devices, especially phones and tablets, a large fraction of the size and weight are the battery. Battery technology keeps improving, and costs go down, and there are dreams of fancy new chemistries and even ultracapacitors, but this has become a dominant issue.
Every device seems to have a different battery. Industrial designers work very hard on the design of their devices, and they don’t want to be constrained by having to standardize the battery space. In many devices, they are even giving up the replaceable battery in the interests of good design. The existing standard battery sizes, such as the AA, AAA and even the AAAA and other less common sizes are just not suitable for a lot of our devices, and while cylindrical form factors make the most sense for many cell designs they don’t fit well in the design of small devices.
So what’s holding back a new generation of standardization in batteries? Is it the factors named above, the fact that tech is changing rapidly, or something else?
I would propose a small, thin modular battery that I would call the EStick, for energy stick. The smaller EStick sizes would be thin enough for cell phones. The goal would be to have more than one b-stick, or at least more than one battery in a typical device. Because of the packaging and connections, that would mean a modest reduction in battery capacity — normally a horrible idea — but some of the advantages might make it worth it.
There are several reasons to have multiple sticks or batteries in a device. In particular, you want the ability to quickly and easily swap at least one stick while the device is still operating, though it might switch to a lower power mode during the swap. The stick slot would have a spring loaded snap, as is common in many devices like cameras, though there may be desire for a door in addition.
Swapping presents the issue that not all the cells are at the same charge level and voltage. This is generally a bad thing, but modern voltage control electronics has reached the level where this should be possible with smaller and smaller electronics. It is possible with some devices to simply use one stick at a time, as long as that provides enough current. This uses up the battery lifetime faster, and means less capacity, but is simpler.
The quick hot swap offers the potential for indefinite battery life. In particular, it means that very small devices, such as wearable computers (watches, glasses and the like) could run a long time. They might run only 3-4 hours on a single stick, but a user could keep a supply of sticks in a pocket or bag to get arbitrary lifetime. Tiny devices that nobody would ever use because “that would only last 2 hours” could become practical.
While 2 or more sticks would be best for swap, a single stick and an internal battery or capacitor, combined with a sleep mode that can survive for 20-30 seconds without a battery could be OK. read more »
Submitted by brad on Sat, 2012-07-28 17:28.
Any speaker or lecturer is familiar with a modern phenomenon. A large fraction of your audience is using their tablet, phone or laptop doing email or surfing the web rather than paying attention to you. Some of them are taking notes, but it’s a minority. And it seems we’re not going to stop this, even speakers do it when attending the talks of others.
However, while we have open wireless networks (which we shouldn’t) there is a trick that could be useful. Build a tool that sniffs the wireless net and calculates what fraction of the computers are doing something that suggests distraction — or doing anything on the internet at all.
While you could get creepy here and do internal packet inspection to see precisely what people are doing (for example, are they searching wikipedia for something you just talked about?) you don’t need to go that far. The simple fact that more people in the room are doing stuff on the internet, or doing heavy stuff on the internet is a clue. You can also tell when people are doing a few core functions, like web surfing vs. SMTP vs. streaming based on the port numbers they are going to. You can also tell if they are doing a common web-mail with the IP address. All of this works even if they are encrypting all their traffic like they should be (to stop prying tools like this!)
Only if they have set up a VPN (which they also should) will you be unable to learn things like ports and IP addresses, but again, it’s a nice indicator to know just what total traffic is, and how many different machines it’s coming from, and that will almost never be hidden.
When the display tells you that most of your audience is using the internet, you could pause and ask for questions or find out why they are surfing. The simple act of asking when distraction gets high will reduce it, and make people embarrassed to have done so. Of course, a sneaky program that learns the MACs of various students could result in the professor asking, “What’s so fascinating on the internet, Mr. Wilson?” At the very least it would encourage the people in the audience to use more encryption. But you don’t have to get that precise. The broad traffic patterns are plenty of information.
Submitted by brad on Sun, 2011-12-18 14:27.
Earlier I wrote about desires for the next generation of DSLR camera and a number of readers wrote back that they wanted to be able to swap the sensor in their camera, most notably so they could put in a B&W sensor with no colour filter mask on it. This would give you better B&W photos and triple your light gathering ability, though for now only astronomers are keen enough on this to justify filterless cameras.
I’m not sure how easy it would be to make a sensor that could be swapped, due to a number of problems — dust, connectivity and more. In fact I wonder if an idea I wrote about earlier — lenses with integrated sensors might have a better chance of being the future.
Here’s another step in that direction — a “foveal” digital camera that has tiny sensors in the middle of the frame and larger ones out at the edges. Such sensors have been built for a variety of purposes in the past, but might they have application for serious photography?
For example, the 5d Mark II I use has 22 million 6.4 micron sensors. Being that large, they are low noise compared to the smaller sensors found in P&S cameras. But the full frame requires very large, very heavy, very expensive lenses. Getting top quality over the large image circle is difficult and you pay a lot for it.
Imagine that this camera has another array, perhaps of around 16 million pixels of 1.6 micron size in the center. This allows it to shoot a 16MP picture in the small crop zone or a 22MP picture on the full frame. (It also allows it to shoot a huge 252 megapixel image that is sharp in the center but interpolated around the edges.) The central region would have transistors that could combine all the wells of a particular colour in the 4x4 array that maps to one large pixel. This is common in the video modes on DSLR cameras, and helps produce pixels that are much lower noise than the tiny pixels are on their own, but not as good as the 16x larger big pixels, though the green pixels, which make up half the area, would probably do decently well.
As a result, this camera would not be as good in low light, and the central region would be no better in low light than today’s quality P&S cameras. But that’s actually getting pretty good, and the results at higher light levels are excellent.
The win is that you would be able to use a 100mm/f2 lens with the field of view of a 400mm lens for a 16MP picture. It would not be quite as good as a real 400mm f/2.8L Canon lens of course. But it could compare decently — and that 400mm lens is immense, heavy and costs $10,000 — far more than the camera body. On the other hand a decent 100mm f/2.8 lens aimed at the smaller image circle would cost a few hundred dollars at most, and do a very good job. A professional wildlife or sports photographer might still seek the $10K lens but a lot of photographers would be much happier to carry the small one, and not just for the saved cost. You would not get the very shallow depth of field of the 400mm f/2.8 — it would be about double with a small sensor 100mm f/2 — but many would consider that a plus in this situation, not a minus.
You could also use 3.2 or 2.1 micron sensors for better low-noise and less of a crop (or focal length multiplier as it is incorrectly called sometimes.)
One other benefit is that, if your lens can deliver it, and particularly when you have decent lighting, you would get superb resolution in the center of your full frame photos, as the smaller pixels are combined. You would get better colour accuracy, without as many bayer interpolation artifacts, as you would truly sense each colour in every pixel, and much better contrast in general. You would be making use of the fact that your lens is sharper in the center. Jpeg outputs would probably never do the 250 megapixel interpolated image, but the raw output could record all the pixels if it is not necessary to combine the wells to improve signal/noise.
Submitted by brad on Fri, 2010-12-31 11:39.
This year, I bought Microsoft Kinect cameras for the nephews and niece. At first they will mostly play energetic X-box games with them but my hope is they will start to play with the things coming from the Kinect hacking community — the videos of the top hacks are quite interesting. At first, MS wanted to lock down the Kinect and threaten the open source developers who reverse engineered the protocol and released drivers. Now Microsoft has official open drivers.
This camera produced a VGA colour video image combined with a Z (depth) value for each pixel. This makes it trivial to isolate objects in the view (like people and their hands and faces) and splitting foreground from background is easy. The camera is $150 today (when even a simple one line LIDAR cost a fortune not long ago) and no doubt cameras like it will be cheap $30 consumer items in a few years time. As I understand it, the Kinect works using a mixture of triangulation — the sensor being in a different place from the emitter — combined with structured light (sending out arrays of dots and seeing how they are bent by the objects they hit.) An earlier report that it used time-of-flight is disputed, and implies it will get cheaper fast. Right now it doesn’t do close up or very distant, however. While projection takes power, meaning it won’t be available full time in mobile devices, it could still show up eventually in phones for short duration 3-D measurement.
I agree with those that think that something big is coming from this. Obviously in games, but also perhaps in these other areas.
Gestural interfaces and the car
While people have already made “Minority Report” interfaces with the Kinect, studies show these are not very good for desktop computer use — your arms get tired and are not super accurate. They are good for places where your interaction with the computer will be short, or where using a keyboard is not practical.
One place that might make sense is in the car, at least before the robocar. Fiddling with the secondary controls in a car (such as the radio, phone, climate system or navigation) is always a pain and you’re really not supposed to look at your hands as you hunt for the buttons. But taking one hand off the wheel is OK. This can work as long as you don’t have to look at a screen for visual feedback, which is often the case with navigation systems. Feedback could come by audio or a heads up display. Speech is also popular here but it could be combined with gestures.
A Gestural interface for the TV could also be nice — a remote control you can’t ever misplace. It would be easy to remember gestures for basic functions like volume and channel change and arrow keys (or mouse) in menus. More complex functions (like naming shows etc.) are best left to speech. Again speech and gestures should be combined in many cases, particularly when you have a risk that an accidental gesture or sound could issue a command you don’t like.
I also expect gestures to possibly control what I am calling the “4th screen” — namely an always-on wall display computer. (The first 3 screens are Computer, TV and mobile.) I expect most homes to eventually have a display that constantly shows useful information (as well as digital photos and TV) and you need a quick and unambiguous way to control it. Swiping is easy with gesture control so being able to just swipe between various screens (Time/weather, transit arrivals, traffic, pending emails, headlines) might be nice. Again in all cases the trick is not being fooled by accidental gestures while still making the gestures simple and easy.
In other areas of the car, things like assisted or automated parking, though not that hard to do today, become easier and cheaper.
Small scale robotics
I expect an explosion in hobby and home robotics based on these cameras. Forget about Roombas that bump into walls, finally cheap robots will be able to see. They may not identify what they see precisely, though the 3D will help, but they won’t miss objects and will have a much easier time doing things like picking them up or avoiding them. LIDARs have been common in expensive robots for some time, but having it cheap will generate new consumer applications.
There will be some gestural controls for phones, particularly when they are used in cars. I expect things to be more limited here, with big apps to come in games. However, history shows that most of the new sensors added to mobile devices cause an explosion of innovation so there will be plenty not yet thought of. 3-D maps of areas (particularly when range is longer which requires power) can also be used as a means of very accurate position detection. The static objects of a space are often unique and let you figure out where you are to high precision — this is how the Google robocars drive.
Security & facial recognition
3-D will probably become the norm in the security camera business. It also helps with facial recognition in many ways (both by isolating the face and allowing its shape to play a role) and recognition of other things like gait, body shape and animals. Face recognition might become common at ATMs or security doors, and be used when logging onto a computer. It also makes “presence” detection reliable, allowing computers to see how and where people are in a room and even a bit of what they are doing, without having to object recognition. (Though as the kinect hacks demonstrate, they help object recognition as well.)
Face recognition is still error-prone of course so its security uses will be initially limited, but it will get better at telling among people.
Virtual worlds & video calls
While some might view this as gaming, we should also see these cameras heavily used in augmented reality and virtual world applications. It makes it easy to insert virtual objects into a view of the physical world and have a good sense of what’s in front and what’s behind. In video calling, the ability to tell the person from the background allows better compression, as well as blanking of the background for privacy. Effectively you get a “green screen” without the need for a green screen.
You can also do cool 3-D effects by getting an easy and cheap measurement of where the viewer’s head is. Moving a 3-D viewpoint in a generated or semi-generated world as the viewer moves her head creates a fun 3-D effect without glasses and now it will be cheap. (It only works for one viewer, though.) Likewise in video calls you can drop the other party into a different background and have them move within it in 3-D.
With multiple cameras it is also possible to build a more complete 3-D model of an entire scene, with textures to paint on it. Any natural scene can suddenly become something you can fly around.
Amateur video production
Some of the above effects are already showing up on YouTube. Soon everybody will be able to do it. The Kinect’s firmware already does “skeleton” detection, to map out the position of the limbs of a person in the view of the camera. That’s good for games but also allows motion capture for animation on the cheap. It also allows interesting live effects distorting the body or making light sabres glow. Expect people in their own homes to be making their own Avatar like movies, at least on a smaller scale.
These cameras will become so popular we may need to start worrying about interference by their structured light. These are apps I thought of in just a few minutes. I am sure there will be tons more. If you have something cool to imagine, put it in the comments.
Happy Seasons to all! and a Merry New Year.
Submitted by brad on Thu, 2010-12-09 00:01.
There are many fields that people expect robotics to change in the consumer space. I write regularly about transportation, and many feel that robots to assist the elderly will be the other big field. The first successful consumer robot (outside of entertainment) was the Roomba, a house cleaning robot. So I’ve often wondered about how far we are from a robot that can tidy up the house. People got excited with a PR2 robot was programmed to fold towels.
This is a hard problem because it seems such a robot needs to do general object recognition and manipulation, something we’re pretty far from doing. Special purpose household chore robots, like the Roomba, might appear first. (A gutter cleaner is already on the market.)
Recently I was pondering what we might do with a robot that is able to pick up objects gently, but isn’t that good at recognizing them. Such a robot might not identify the objects, but it could photograph them, and put them in bins. The members of the household could then go to their computers and see a visual catalog of all the things that have been put away, and an indicator of where it was put. This would make it easy to find objects.
The catalog could trivially be sorted by when the items were put away, which might well make it easy to browse for something put away recently. But the fact that we can’t do general object recognition does not mean we can’t do a lot of useful things with photographs and sensor readings (including precise weight and other factors) beyond that. One could certainly search by colour, by general size and shape, and by weight and other characteristics like rigidity. The item could be photographed in a 360 view by being spun on a table or in the grasping arm, or which a rotating camera. It could also be laser-scanned or 3D photographed with new cheap 3D camera techniques.
When looking for a specific object, one could find it by drawing a sketch of the object — software is already able to find photos that are similar to a sketch. But more is possible. Typing in the name of what you’re looking for could bring up the results of a web image search on that string, and you could find a photo of a similar object, and then ask the object search engine to find photos of objects that are similar. While ideally the object was photographed from all angles, there are already many comparison algorithms that survive scaling and rotation to match up objects.
The result would be a fairly workable search engine for the objects of your life that were picked up by the robot. I suspect that you could quickly find your item and learn just exactly where it was.
Certain types of objects could be recognized by the robot, such as books, papers and magazines. For those, bar-codes could be read, or printing could be scanned with OCR. Books might be shelved at random in the library but be easily found. Papers might be hard to manipulate but could at least be stacked, possibly with small divider sheets inserted between them with numbers on them, so that you could look for the top page of any collected group of papers and be told, “it’s under divider 20 in the stack of papers.” read more »
Submitted by brad on Fri, 2009-12-18 15:18.
I’m waiting for the right price point on a good >24” monitor with a narrow bezel to drop low enough that I can buy 4 or 5 of them to make a panoramic display wall without the gaps being too large.
However, another idea that I think would be very cool would be to exploit the gaps between the monitors to create a simulated set of windows in a wall looking out onto a scene. It’s been done before in lab experiments with single monitors, but not as a large panoramic installation or something long term from what I understand. The value in the multi display approach is that now the gap between displays is a feature rather than a problem, and viewers can see the whole picture by moving. (Video walls must edit out the seams from the picture, removing the wonderful seamlessness of a good panorama.) We restore the seamlessness in the temporal dimension.
To do this, it would be necessary to track the exact location of the eyes of the single viewer. This would only work for one person. From the position of the eyes (in all 3 dimensions) and the monitors the graphics card would then project the panoramic image on the monitors as though they were windows in a wall. As the viewer’s head moved, the image would move the other way. As the viewer approached the wall (to a point) the images would expand and move, and likewise shrink when moving away. Fortunately this sort of real time 3-D projection is just what modern GPUs are good at.
The monitors could be close together, like window panes with bars between them, or further apart like independent windows. Now the size of the bezels is not important.
For extra credit, the panoramic scene could be shot on layers, so it has a foreground and background, and these could be moved independently. To do this is would be necessary to shoot the panorama from spots along a line and both isolate foreground and background (using parallax, focus and hand editing) and also merge the backgrounds from the shots so that the background pixels behind the foreground ones are combined from the left and right shots. This is known as “background subtraction” and there has been quite a lot of work in this area. I’m less certain over what range this would look good. You might want to shoot above and below to get as much of the hidden background as possible in that layer. Of course having several layers is even better.
The next challenge is to very quickly spot the viewer’s head. One easy approach that has been done, at least with single screens, is to give the viewer a special hat or glasses with easily identified coloured dots or LEDs. It would be much nicer if we could do face detection as quickly as possible to identify an unadorned person. Chips that do this for video cameras are becoming common, the key issue is whether the detection can be done with very low latency — I think 10 milliseconds (100hz) would be a likely goal. The use of cameras lets the system work for anybody who walks in the room, and quickly switch among people to give them turns. A camera on the wall plus one above would work easily, two cameras on the left and right sides of the wall should also be able to get position fairly quickly.
Even better would be doing it with one camera. With one camera, one can still get a distance to the subject (with less resolution) by examining changes in the size of features on the head or body. However, that only provides relative distance, for example you can tell if the viewer got 20% closer but not where they started from. You would have to guess that distance, or learn it from other queues (such as a known sized object like the hat) or even have the viewer begin the process by standing on a specific spot. This could also be a good way to initiate the process, especially for a group of people coming to view the illusion. Stand still in the spot for 5 seconds until it beeps or flashes, and then start moving around.
If the face can be detected with high accuracy and quickly, a decent illusion should be possible. I was inspired by this clever simulated 3-D videoconferencing system which simulates 3-D in this way and watches the face of the viewer.
You need high resolution photos for this, as only a subset of the image appears in the “windows” at any given time, particularly when standing away from the windows. It could be possible to let the viewer get reasonably close to the “window” if you have a gigapan style panorama, though a physical barrier (even symbolic) to stop people from getting so close that the illusion breaks would be a good idea.
Submitted by brad on Mon, 2009-11-23 14:29.
As digital cameras have developed enough resolution to work as scanners, such as in the scanning table proposal I wrote about earlier, some people are also using them to digitize slides. You can purchase what is called a “slide copier” which is just a simple lens and holder which goes in front of the camera to take pictures of slides. These have existed for a long time as they were used to duplicate slides in film days. However, they were not adapted for negatives since you can’t readily duplicate a colour negative this way, because it is a negative and because it has an orange cast from the substrate.
There is at least one slide copier (The Opteka) which offers a negative strip holder, however that requires a bit of manual manipulation and the orange cast reduces the color gamut you will get after processing the image. Digital photography allows imaging of negatives because we can invert and colour adjust the result.
To get the product I want, we don’t have too far to go. First of all, you want a negative strip holder which has wheels in the sprocket holes. Once you have placed your negative strip correctly with one wheel, a second wheel should be able to advance exactly one frame, just like the reel in the camera did when it was shooting. You may need to do some fine adjustments, but it is also satisfactory to have the image cover more than 36mm so that you don’t have to be perfectly accurate, and have the software do some cropping.
Secondly, you would like it so that ideally, after you wind one frame, it triggers the shutter using a remote release. (Remote release is sadly a complex thing, with many different ways for different cameras, including wired cable releases where you just close a contact but need a proprietary connector, infrared remote controls and USB shooting. Sadly, this complexity might end up adding more to the cost than everything else, so you may have to suffer and squeeze it yourself.) As a plus, a little air bulb should be available to blow air over negatives before shooting them.
Next, you want an illuminator behind the negative or slide. For slides you want white of course. For negatives however, you would like a colour chosen to undo the effects of the orange cast, so that the gamut of light received matches the range of the camera sensors. This might be done most easily with 3 LEDs matched to camera sensors in the appropriate range of brightness.
You could also simply make a product out of this light, to be used with existing slide duplicators; that’s the simplest way to do this in the small scale.
Why do all this, when a real negative scanner is not that expensive, and higher quality? Digitizing your negatives this way would be fast. Negative scanners all tend to be very slow. This approach would let you slot in a negative strip, and go wind-click-wind-click-wind-click-wind-click in just a couple of seconds, not unlike shooting fast on an old film camera. You would get quite decent scans with today’s high quality DLSRs. My 5d Mark II with 21 megapixels would effectively be getting around 4000 dpi, though with bayer interpolation. If you wanted a scan for professional work or printing, you could then go back to that negative and do it on a more expensive negative scanner, cleaning it first etc.
Another solution is just to send all the negatives off to one of the services which send them to India for cheap scanning, though these tend to be at a more modest resolution. This approach would let you quickly get a catalog of your negatives.
Of course, to get a really quick catalog, another approach would be to create a grid of 3 rows of negative strip holder which could then be placed on a light table — ideally a light table with a blueish light to compensate for the orange cast. Take a photo of the entire grid to get 12 individual photos in one shot. This will result (on the 5D) in about 1.5 megapixel versions of each negative. Not sufficient to work with but fine for screen and web use, and not too far off the basic service you get from the consumer scanning companies.
I have some of my old negatives in plastic sheets that go in binders, so I could do it directly with them, but it’s work to put negatives into these and would be much easier to slide strips into a plastic holder which keeps them flat. Of course, another approach would be to simply lay the strips on the light table and put a sheet of clear plexiglass on top of them, and shoot in a dim room to avoid reflections.
It would also be useful if digital cameras or video cameras tossed in a “view colour negative” mode which did its best to show an invert of the live preview image with orange cast reverted. Then you could browse your negatives by holding them up to your camera (in macro mode) and see them in their true form, if at lower resolution. Of course you can usually figure out what’s in a negative but sometimes it’s not so easy and requires the loupe, and it might not in this case.
Submitted by brad on Wed, 2009-09-30 14:47.
I have several sheetfed scanners. They are great in many ways — though not nearly as automatic as they could be — but they are expensive and have their limitations when it comes to real-world documents, which are often not in pristine shape.
I still believe in sheetfed scanners for the home, in fact one of my first blog posts here was about the paperless home, and some products are now on the market similar to this design, though none have the concept I really wanted — a battery powered scanner which simply scans to flash cards, and you take the flash card to a computer later for processing.
My multi-page document scanners will do a whole document, but they sometimes mis-feed. My single-page sheetfed scanner isn’t as fast or fancy but it’s still faster than using a flatbed because the act of putting the paper in the scanner is the act of scanning. There is no “open the top, remove old document, put in new one, lower top, push scan button” process.
Here’s a design that might be cheap and just what a house needs to get rid of its documents. It begins with a table which has an arm coming out from one side which has a tripod screw to hold a digital camera. Also running up the arm is a USB cable to the camera. Also on the arm, at enough of an angle to avoid glare and reflections are lighting, either white LED or CCFL tubes.
In the bed of the table is a capacitive sensor able to tell if your hand is near the table, as well as a simple photosensor to tell if there is a document on the table. All of this plugs into a laptop for control.
You slap a document on the table. As soon as you draw your hand away, the light flashes and the camera takes a picture. Then go and replace or flip the document and it happens again. No need to push a button, the removal of your hand with a document in place causes the photo. A button will be present to say “take it again” or “erase that” but you should not need to push it much. The light should be bright enough so the camera can shoot fairly stopped down, allowing a sharp image with good depth of field. The light might be on all the time in the single-sided version.
The camera can’t be any camera, alas, but many older cameras in the 6MP range would get about 300dpi colour from a typical letter sized page, which is quite fine. Key is that the camera has macro mode (or can otherwise focus close) and can be made to shoot over USB. An infrared LED could also be used to trigger many consumer cameras. Another plus is manual focus. It would be nice if the camera can just be locked in focus at the right distance, as that means much faster shooting for typical consumer digital cameras. And ideally all this (macro mode, manual focus) can all be set by USB control and thus be done under the control of the computer.
Of course, 3-D objects can also be shot in this way, though they might get glare from the lights if they have surfaces at the wrong angles. A fancier box would put the lights behind cloth diffusers, making things bulkier, though it can all pack down pretty small. In fact, since the arm can be designed to be easily removed, the whole thing can pack down into a very small box. A sheet of plexi would be available to flatten crumpled papers, though with good depth of field, this might not strictly be necessary.
One nice option might be a table filled with holes and a small suction pump. This would hold paper flat to the table. It would also make it easy to determine when paper is on the table. It would not help stacks of paper much but could be turned off, of course.
A fancier and bulkier version would have legs and support a 2nd camera below the table, which would now be a transparent piece of plexiglass. Double sided shots could then be taken, though in this case the lights would have to be turned off on the other side when shooting, and a darkened room or shade around the bottom and part of the top would be a good idea, to avoid bleed through the page. Suction might not be such a good idea here. The software should figure if the other side is blank and discard or highly compress that image. Of course the software must also crop images to size, and straighten rectangular items.
There are other options besides the capacitive hand sensor. These include a button, of course, a simple voice command detector, and clever use of the preview video mode that many digital cameras now have over USB. (ie. the computer can look through the camera and see when the document is in place and the hand is removed.) This approach would also allow gesture commands, little hand signals to indicate if the document is single sided, or B&W, or needs other special treatment.
The goal however, is a table where you can just slap pages down, move your hand away slightly and then slap down another. For stacks of documents one could even put down the whole stack and take pages off one at a time though this would surely bump the stack a bit requiring a bit of cleverness in straightening and cropping. Many people would find they could do this as fast as some of the faster professional document scanners, and with no errors on imperfect pages. The scans would not be as good as true scanner output, but good enough for many purposes.
In fact, digital camera photography’s speed (and ability to handle 3-D objects) led both Google Books and the Internet Archive to use it for their book scanning projects. This was of course primarily because they were unwilling to destroy books. Google came up with the idea of using a laser rangefinder to map the shape of the curved book page to correct any distortions in it. While this could be done here it is probably overkill.
One nice bonus here is that it’s very easy to design this to handle large documents, and even to be adjustable to handle both small and large documents. Normally scanners wide enough for large items are very expensive.
Submitted by brad on Wed, 2009-09-09 11:40.
After every RV trip (I’m back from Burning Man) I think of more I want RVs to do. This year, as we have for many years, we built a power distribution system with a master generator rather than having each RV run its own noisy, smelly and inefficient generator. However, this is expensive and a lot of work for a small group, it is cheap and a lot of work for a larger group.
There’s been a revolution in small generator design of late thanks to the declining cost of inverters and other power conversion. A modern quality generator feeds the output of its windings to circuits to step up and step down the voltage to produce the required power. The output power is cleaner and more stable, and the generator is spun at different RPMs based on the power load, making it quieter and more efficient. With many models, you can also combine the internal output of two generators to produce a higher power generator.
RVs have come with expensive old-style generators that are quieter than cheap ones, and which produce better power, but today they are moving to inverter generators. With an inverter generator, it’s also possible to draw on the RV batteries for power surges (such as starting an AC or microwave) beyond what the generator can do.
I’m interested in the potential for smarter power, so what I would like to see is a way for a group of RVs with new generation power systems to plug together. In this way, they could all make use of the power in the other vehicles, and in most cases only a fraction of the generators would need to be running to provide power to all. (For example, at night, only one generator could power a whole cluster. In the day, with ACs running, several would need to run, but it would be very unlikely to have to run all, or even 75% of them.) read more »
Submitted by brad on Tue, 2009-08-25 23:39.
RVs all have a fresh water tank. When you rent one, they will often tell you not to drink that water. That’s because the tanks are being filled up in all sorts of random places, out of the control of the rental company, and while it’s probably safe, they don’t want to promise it, nor disinfect the tank every rental.
I recently got a small “pen” which you put in a cup of water and it shines a UV light for 30 seconds to kill any nasties in the water. While I have not tried to test it on infected water, I presume that it works.
So it seems it makes sense to me to install this sort of UV tube in the fresh water tank of RVs. Run it from time to time, and particularly after a fill, and be sure the water is clean. Indeed, with an appropriate filter, and a 2nd pump, such an RV could happily fill its water tank from clear lakes and streams, allowing longer dry camping which should have a market. Though of course the gray/black water tanks still will get full, but outside showers and drinking do not fill those tanks.
A urination-only toilet could also be done if near a stream or lake.
Submitted by brad on Sun, 2009-06-14 23:15.
Many RVs come with generators, and the air conditioner is the item that demands it be a high power generator. The Generator needs to be big enough to run the AC, and in theory let you do other things like microwave when you run it. It also has to be big enough to handle the surge that the AC motor takes when the AC starts up.
This surge is huge, and will often overload a generator, particularly external generators that are commonly used on smaller RVs. To fix this problem, there’s been a bit of effort to develop “soft start” electric motor technologies that start up motors slowly, and store charge in a big capacitor in order to provide the surge.
However, the RV also has a deep cycle battery and (if a motorhome) an engine starting battery. Both these batteries can usually deliver 100 or more amps in a burst. (The engine starting battery can deliver several hundred.)
Today, high-power inverters have gotten much cheaper, even those that can deliver 500 to 1,000 watts (and peak to far more) are getting cheap. I have wondered why it has not become standard to include a high power inverter in any RV so that small 110v appliances can’t be run off the battery for short times, rather than firing up the generator. To microwave something for 30 seconds requires starting the generator which is quite wasteful, and also noisy. Of course, what runs off the battery should still run on 12 volts, and some things (like the fridge in electric mode) should not run off an inverter. Short microwave bursts, and a few hours of flatscreen TV watching can run off an inverter.
And so my proposal is that such an inverter also be available to provide surge power to the AC compressor when it starts, even if the generator or shore power is on. The extra 1000 or so watts the inverter can provide would allow the use of a smaller, cheaper generator. This requires an inverter that can sync to the phase of the incoming AC, and of course safety circuits to assure that power is not fed back into the shore power port when it is disconnected.
Today, the big trend in generators is actually to have them use such high-power inverters. The generators are thus free to generate dirty power, and to run at whatever RPM is best for them at the time. The inverter cleans up the power and puts out clean, constant voltage. There are modest losses but overall it’s a win, as you get a generator that is much more efficient and quiet, and better quality power. Many suspect that RV generators will switch to that approach. In this case, it becomes much easier to have an integrated inverter generator able to also draw from the battery for its surges. No need for grid tie logic in this case.
To wit, one could see a system where a 2kw inverter generator, able to boost to 3.5kw by adding in the battery, could be enough for a typical RV, even with a decent sized AC. You might have to have a circuit that says “If the microwave or other big load is on, don’t start the compressor” but that would only be an issue if you wanted to microwave something for a long time on high. Note in a proper AC the compressor is not running all the time, so the AC would not be off — it would just not be doing on cycles during the microwave use.
There would probably be some 110v plugs in the RV which are marked “On under shore or generator power only” vs “always on,” or possibly switches to control if they are on the inverter or not, since there are loads you would want to make sure stay off if running only on battery. A little more complexity to the internal wiring, but a big saving on generator size and a better dry camping experience. It also means a more usable RV when plugging into a 15 amp external shore power line. In many RVs, plugging into 15 amps is not enough to start the AC, and certainly not enough to run the AC and another device. The power control system would want to know if it’s plugged into 15A, 20A or the normal 30A. And it would also want to notice if something is drawing too much battery power and shut it off before the battery gets too low.
Obviously as well, the 12 volt converter and battery charger must only run off true shore power or the generator, never off the inverter!
Submitted by brad on Wed, 2009-05-20 14:10.
In my quest for the idea panorama head, I have recently written up some design notes and reviews. I found that the automatic head I tried, the beta version of the Gigapan turned out to be too slow for my tastes. I can shoot by hand much more quickly.
Manual pano heads either come with a smooth turning rotator with markers, or with a detent system that offers click-stops at intervals, like 15, 20 or 30 degrees. Having click-stops is great in theory — easy to turn, much less chance of error, more exact positioning. But it turns out to have its problems.
First, unless you shoot with just one lens, no one interval is perfect. I used to shoot all my large panos with a 10 degree interval which most detent systems didn’t even want to support. Your best compromise is to pick a series of focal lengths that are multiples. So if you shoot with say a 50mm and near-25mm lens, you can use a 15 degree interval, and just go 2-clicks for 30 degrees and so on. (It’s not quite this simple, you need more overlap at the wider focal lengths.)
Changing the click stops is a pain on some rotators — it involves taking apart the rotator, which is too much no matter how easy they make that. The new Nodal Ninja rotators and some others use a fat rotator with a series of pins. This is good, but the rotator alone is $200.
Click stops have another downside. You want them to be firm, but when they are, the “click” sets up vibrations in the assembly, which has a long lever arm, especially if there is a telephoto lens. Depending on the assembly it can take a few seconds for those vibrations to die down.
So here’s a proposal that might be a winner: electronic click stops. The rotator ring would have fine sensor marks on it, which would be read by a standard index photosensor. This would be hooked up to an inexpensive microcontroller. The microcontroller in turn would have a small piezo speaker and/or a couple of LEDs. The speaker would issue a beep when the camera was in the right place, and also issue a sub-tone which changes as you get close to the right spot — a “warmer/colder” signal to let you find it quickly. LEDs could blink faster and faster as you get warmer, and go solid when on the right spot. They would also warn you if you drifted too far from the spot before shooting.
Now this alone would be quite useful, and of course, fully general as it could handle any interval desired. Two more things are needed — a way to set the interval, and optionally a way to ease the taking of the photos.
To set the interval, you might first reset the device by giving it a quick spin of 360 degrees. It would give a distinctive beep when ready. Then you would look through the viewfinder and move the desired interval. Your interval would be set. If doing a multi-row you would have 2 sensors for angle, and you would do this twice. You could have a button for this, but I am interested in avoiding buttons.
Now you would be ready to shoot. It would give a special signal after you had shot 360 degrees or the width of the first row in a multi-row.
Other modes could be set with other large motions of the rotator, such as moving it back and forth 2 times quickly, or other highly atypical rotations.
(If you want buttons, an interesting way to do this is to have an IR sensor and to accept controls from other remotes, such as a universal TV remote set to a Sony TV, or some other tiny remote control which is readily available. Then you can have all the buttons and modes you want.)
We might need to have one button (for on/off) and since off could be a long press-and-hold, the button could also be used for interval setting and panorama starting.
The next issue is automatic shooting or shot detection. The sensor, since it will be finely tuned, will be able to tell when you’ve stopped at the proper stop. When all movement ceases, it could take the shot without you pressing the shutter using a bunch of methods. It might also be useful to have you manually control the shutter, but via a button on the panohead rather than the camera’s own shutter or cable release. First of all, this would let the head know you had taken the shot, so it could warn you about any shot that was missing. It could also know if you bumped the head or moved it during any shot — when doing long exposures there is a risk of doing this, especially if you are too eager for the next shot.
Secondly, you should always be using a cable release anyway, so building one into the pano head makes some sense. However, this need not be included in the simplest form of the product.
One very cheap way of having the pano head fire the shutter is infrared. Many cameras, though sadly not all, will let you control the shutter with infrared. Digital SLRs stopped doing this for a while, but now Canon at least has reversed things and supports infrared remote on the 5D Mark II. I think we can expect to see more of this in future. Another way is with a custom cable into the camera’s cable release port. The non-standard connectors, such as the Canon N3, can now be bought but this does mean having various connector adapters available, and plugging them in.
A third way is via USB. This is cheap and the connector is standard, but not all cameras will fire via USB. Fortunately more and more microcontroller chipsets are getting USB built in. The libgphoto2 open source library will control a lot of cameras. Of course, if you have a fancy controller, you can do much more with USB, such as figure out the field of view of the camera from EXIF but that’s beyond the scope of a simple system like this.
The fourth way is a shutter servo, again beyond the scope of a small system like this. In addition, all these methods beg more UI, and that means more buttons and even eventually a screen if an LED and speaker can’t tell you all you need. However, in this case what’s called for is a button which you can use to fire the shutter, and which you can press and hold before starting a pano to ask for auto firing.
The parts cost of all this is quite small, especially in any bulk. Cheaper than a machined detent system, in fact. In smaller volumes, a pre-assembled microcontroller board could be used, such as the Arduino or its clones. The only custom part might be the optical rotary encoder disk, but a number of vendors make these in various sizes.
I’ve talked about this system being cheap but in fact it has another big advantage, which is it can be small. It’s also not out of the question that it could be retrofitted onto existing pano heads, as just about everybody is already carrying a ballhead or pan/tilt head. For retrofit, one would glue an index mark tape around the outside of your existing head near where it turns, and mount the sensor and other equipment on the other part. The result is a panohead that weighs nothing because you are already carrying it.
Update: I am working on even more sophisticated plans than this which could generate a panohead which is the strongest, smallest, fastest, most versatile and lightest all at the same time — and among the less expensive too. But I would probably want some partners if I were to manufacture it.
Submitted by brad on Fri, 2009-01-23 14:51.
In the early days of microprocessors, people selling home computers tried to come up with reasons to have them in the home. The real reason you got one was hobby computing, but the companies wanted to push other purposes. A famous one was use in the kitchen. The computer could story your recipe file, and wonder of wonders, could change the amounts of the ingredients based on how many servings you wanted to make.
This never caught on, but computers have come a long way. But still, I mostly see nonsense applications promoted. For example, boosters of RFID tell us that our fridges will be able to track when things went in the fridge, and when it’s time to buy more milk. We should give up huge amounts of privacy to figure out when to order more milk?
With that track record, I should stay away from the area, but let me propose some interesting approaches in the kitchen.
The cooking area should have a screen, of course. Screens are already in the kitchen to watch TV. While you could (and would) put digital recipes up on the screen, I imagine going further, and having TV cooking shows, where you watch a chef prepare a dish. You would be able to pause, rewind and do everything that digital video does, but the show would also come along with encoded instructions tagged to points in the video. When the recipe calls for cooking for 5 minutes, the computer would start appropriate timers.
The computer should have a speech interface, and a good one, allowing you to call out for timers, and to name ingredients and temperatures. More on that later.
The first thing I would like to see is smart, digital wireless scales in a lot of places. A general one on the counter of course, but quite possibly also built into the rack above the burner which holds the pot. You can get scales built into spoons and scoops now, and they could be bluetooth. read more »
Submitted by brad on Sat, 2008-10-11 12:48.
I have tripods with both 3 segments and 4 segments. A 4-segment tripod has 3 clamps per leg, which means 9 of them to open and close in extending and collapsing the tripod. That’s a pain. Enough of one that you sometimes find yourself asking whether a shot is worth setting up the tripod. But even 3 segment tripods are only a bit better.
I have my 4-segment legs because I can pack the tripod down into a reasonably small suitcase. I do most shooting when I travel so this is actually my best carbon fiber tripod. But when I am out carrying the tripod, or more commonly carrying it in the car, it doesn’t need to be this short. Unfortunately, the tripod fully extended, with camera and pano mount on it, is too long to fit in most cars, so I have to collapse one set of legs. That’s not so hard but it’s still very long and unweildy with just one set collapsed.
Here’s a possible answer: A 4 segment tripod where the bottom two segments join not with an external clamp, but which screw or snap together to make a smooth double-length segment. You used to be able to get monopods like this. Of course, the threaded join is not very convenient, and is not adjustable. However, you could readily take it apart to pack the tripod in a suitcase. If it can be made strong enough, a snap-together join would be best, with some recessed buttons to push to pull the legs apart. Then takedown and setup could be quick enough that you would also use it to put the pod into a backpack.
However, what you would have when put together is a 2-segment tripod, because the lower pair of segments, with no bumpy clamp, could feed up into the upper two segments when both of those are extended. In other words, you would have a nice tripod you could quickly reduce to half its length and back with just 3 clamps. A reasonable length for carrying and a very easy length to put into a car trunk or back seat.
You would not, however, be able to make the tripod any shorter than half-length without undoing the bottom join. Then you could get the tripod down to 1/4 length for low shots and for placing on tables and stone walls if half-length was just too high. That use is rare enough that I could handle that, especially if it’s just snaps.
The same approach could apply to your center column, or you could have just a 1/4 length center column, which is fine for most applications, since you don’t want to extend the column unless you have to, normally.
Note that the top join would be normal, so you would have 2 clamps per leg, and one hard-join. You don’t want a hard join at the top because presumably that will thin the inner diameter of the pole if you want it strong, stopping the lower segment from telescoping inside.
The 3rd segment (2nd from the ground) into which the bottom segment snaps, could also possibly have a spike or small foot coming out the center, which goes into a hole in the bottom segment. Or a place to attach such a foot. This would allow you to also configure a shorter, 3-segment standard tripod when you don’t want to snap in the lowest segment.
Submitted by brad on Fri, 2008-08-15 19:09.
Ok, this is something I have to believe somebody else has thought of, but I haven’t seen it, so I thought I would ask readers if they have, and if not, to put it forward.
Everybody has a socket wrench set. The wrench heads tend to come with a square hole in the top, typically 1/2” or 3/8” square, into which the square drive from the ratchet inserts. There are sometimes spring-locks to keep it in place.
However, when you have a nut that’s going on a long bolt, you can’t use a standard socket as the bolt won’t fit inside. So you need to get a “deep socket” head, which may be able to handle the long bolt. Yes, you shouldn’t have such long bolts, and perhaps should saw off the end, but in reality this happens in places where that’s not easy or worthwhile. You can’t have just a deep socket set, because that’s bigger and heavier to carry around, and may not fit in various confined spaces.
The problem is that the drive is a solid square pin inside the wrench head. If the drive were able to grasp the wrench head from the outside, like a standard nut, then you could have an “extender” which could make any of your sockets a deep socket. To do this, the top of the wrench head would not be round, as it typically is, but hexagonal. In fact, your “extender” could simply be another, larger wrench from the set which fits around this hex head. Or you could have a small number of extenders in various sizes, and in extreme cases, multiple extenders. The extenders might do well to also have spring locks like the current drives do, to hold elements in place for you.
One could also have a thin hex shell embedded in the socket, the way lockable lug-nuts do, but that would not be as strong. Of course, one could try to do a whole new type of driver which is hollow, but the existing drivers are so well standardized now (there are not even metric versions) that I doubt it would get much adoption.
While we’re on this topic, here’s another idea. Organizing socket wrenches in a case is a pain. They often fall out and it’s hard to put them all back in the right place. I’ve seen colour coded sockets (fairly good) and laser etched numbers that are easier to read, and cases that try to bind the wrenches so they won’t fall out as easily. Realizing that the outside does not have to be round, I wonder if we could have patterns at the nut-end of the wrench that make it easy to slot how they go into their case. Perhaps just a couple of bumps or notches, so that no wrench can go in the wrong slot, even a slot for the wrench that is just a bit bigger.