Secrets of the "Clear" airport security line

Yesterday it was announced that “Clear” (Verified ID Pass) the special “bypass the line at security” card company, has shut its doors and its lines. They ran out of money and could not pay their debts. No surprise there, they were paying $300K/year rent for their space at SJC and only 11,000 members used that line.

As I explained earlier, something was fishy about the program. It required a detailed background check, with fingerprint and iris scan, but all it did was jump you to the front of the line — which you get for flying in first class at many airports without any background check. Their plan, as I outline below, was to also let you use a fancy shoe and coat scanning machine from GE, so you would not have to take them off. However, the TSA was only going to allow those machines once it was verified they were just as secure as existing methods — so again no need for the background check.

To learn more about the company, I attended a briefing they held a year ago for a contest they were holding: $500,000 to anybody who could come up with a system that sped up their lines at a low enough cost. I did have a system, but also wanted to learn more about how it all worked. I feel sorry for those who worked hard on the contest who presumably will not be paid.  read more »

The background check

Features for high-end digital cameras

I’m really enjoying my Canon EOS 5D Mark II, especially its ability to shoot at 3200 ISO without much noise, allowing it to be used indoors, handheld without flash. But as fine as this (and other high end) cameras are, I still see a raft of features missing that I hope will appear in future cameras.

Help me fix my mistakes

A high end camera has full manual settings, which is good. But even the best of us make mistakes with these settings, mistakes the camera should know about and warn us about. It should not stop us from making shots, or in many circumstances try to correct the mistakes. But it should notice them, and beep when I take a picture, and show the mistake on the display with menu options to correct it, to always correct it, or not not warn me again about it for a day or forever.

I write earlier about the general principle of noticing when we’ve left the camera in an odd mode. If we put the camera into incandescent white balance in the evening and then a day later the camera notice we’re shooting in a sunny environment, it should know and alert us, or even fix it. This is true of a variety of settings that are retained through a non-shooting period, including exposure compensation, white balance, shooting modes, ISO changes and many others. The camera should learn over time what our “normal” modes are that we do like to leave the camera in, and not warn us about them, but warn us about other unusual things.

Many things will be obvious to the camera. If I shoot in manual mode and then later take another shot in manual mode that’s obviously way overexposed or underexposed, I probably just forgot, and would not mind the reminder. The reminder might also offer to delete the bad shot.

There are many things the camera can detect, including big blobs of sensor dust. Lenses left in manual focus should be noticed after a long gap of time, and especially if the lens has been removed and returned to the camera. Again, this should not impinge on the UI much — just a beep and a chance to see what the problem was on the screen.

Add bluetooth and other communications protocols to the camera

Let the camera talk to other devices. One obvious method would be bluetooth. With that, let the camera use bluetooth microphones and headsets when it records video and annotations. Let me hear the camera’s beeps and audio in a bluetooth headset so as not to disturb others. Let the camera talk to a Bluetooth GPS or GPS equipped phone to get geolocation data for photos. Let the camera be controlled via bluetooth from a laptop, and let it upload photos to a computer as it currently can do over USB. Let me use my phone or any other bluetooth remote as a remote control for the camera — indeed, on a smart phone, let me go so far as to control all aspects of the camera and see the live preview. Start making bluetooth controlled flash modules to replace the infrared protocols — it’s more reliable and won’t trigger other people’s flashes. Build simple bluetooth modules that can connect to the hotshoe or IR of existing flashes to convert them to this new system. Bluetooth would also allow keyboards (and even mice) for fancier control of the camera, and configuration of parameters that today require software on a PC. A bluetooth mouse, with its wheels (like the camera’s wheels) could make an interesting remote control.

With Bluetooth 3.0, which can go 480 megabits, this is also a suitable protocol for downloading photos or live tethering. Wireless USB (also 480 megabits at short range) is another contender.

Let it be a USB master as well as slave, so it can also be connected to USB GPSs and other peripherals dream up, including cell phones, most of which can now be a USB slave. This would also allow USB microphones, speakers and video displays.

Finally, add a protocol (USB or just plain IP) to the hot shoe to make this happen. (See below.)

Make more use of the microphone

I’ve always liked the idea of capturing a few seconds of sound around every still photo. This can be used for mood, or it can be used for notes on the photo. Particularly if we can do speech-to-text on the audio later, so that I can put captions on photos right then and there. This would work especially well if I can get a bluetooth headset with high quality microphone audio, something that is still hard to do right now.

If your camera can shoot video, it can of course be used as an audio recorder by putting on the lens cap, but why not just offer a voice recorder mode once you have gone to the trouble to support a good microphone.

Treat the camera as a software platform

Let other people write code to run on the camera. Add-on modules and new features. For low-end, deliberately crippled cameras this might not be allowed, but if I’m paying more for my camera than a computer, I should be able to program it, or download other people’s interesting programs.

Furthermore, let this code send signals to other devices, over USB, the flash shoe, and even bluetooth. Consider including a few general purpose digital read/write pins for general microcontroller function, or make a simple module to allow that.

Letting others write code for your product has a cost — you must define APIs and support them. But the benefits are vast, and would generate great loyalty to the camera to do this first. I imagine software for panorama taking, high-dynamic range photography, timelapse, automatic exposure evaluation and much more — perhaps even the mistake-detection described above.

Create a fancy new hotshoe with data flow and power flow

The hotshoe should include a generalized data bus like two-way USB or just IP over something. Make all peripherals, including flashes, speak this protocol for control. But also allow the unit on the flash hot shoe to control the camera — this will be a two way street.

In the hotshoe, include pins for power — both to access the power from the camera, and to allow hotshoe devices to assist powering the camera and to charge the battery. This would allow the creation of low-powered flashes which are small and don’t need a battery because they draw from the camera battery. Not big, but suitable for fill flash and other purposes. The 5D has no built-in flash and I miss the fill-flash of the on-camera flash of the 40D. Obviously you don’t want devices sucking all the battery, and some might have their own batteries, but I would rather carry two camera batteries than have to carry a camera battery and then another battery type and charger type for my flash!

One could make a hotshoe device that holds more camera batteries, as an alternative to the battery grip. But hotshoe devices, with their data link, could do much more than control flashes. They could include fancy audio equipment, even a controller for the servo motors of a rotating pano-head or pan and scan tripod. Hotshoe devices could include wifi or bluetooth if it’s not already in the phone. Or GPS location.

The Hotshoe would offer 5v USB style power to start, but on approval, switch the power lines to high-current direct battery access, to allow extra power devices, and even battery chargers or AC adapters.

Support incremental download

Perhaps some cameras do this but I have not seen it. Instead of deleting photos from cards, just let things cycle through, and have the downloader only fetch the new photos, and mark the ones fetched as ready for deletion when needed. It’s always good to have your photos in multiple places — why delete them from the card before you need to? Possibly make the old photos semi-invisible. And, as I have asked before, when a photo is deleted, don’t delete it, but move it to a recycle bin where I can undelete. Of course, as space is needed, purge things from that bin in order. Though still call it delete, so that when rent-a-cops try to make you delete photos, you can fake it.

Put an Arca-swiss style plate on the bottom of the camera

Serious photographers have all settled on this plate, and have one stuck to the bottom of their camera, which is annoying when the camera is on your neck. Put these dovetails right into the base of the camera, with a standard tripod hole in the center (as these plates often can’t quite do as they must put the screw in the center.) I pay $50 for every new camera to get a custom plate. Just build it in. Those with other QR systems can still connect to the 1/4-20 tripod hole.

Consider a new format between jpeg and raw

The jpeg compression is good enough that detail is not lost. What is lost is exposure range. Raw format preserves everything, but is very large and slower and harder to use when organizing photographs — its main value is in post-processing photographs. A 12 bit jpeg standard exists, but is not widely used, but if cameras started offering it, I expect we would see support for it proliferate, even faster than support for raw has done.

Show me the blurries

A feature I have been requesting for some time. After I take a photo, let one of the review modes offered provide a zoom in of something that is supposed to be in focus. That could be the best focus point, or simply the most contrasty part of the photo. If, when I see the most contrasty part of the photo, it’s still blurry, I can know I didn’t focus right or hold the camera steady enough. If using focus points, the wheel could rotate around the focus points that were supposed to be in focus, so I can see what was probably my subject and how well it was shot.

Have a good accelerometer, and use it

Most cameras have a basic accelerometer to know if the camera is in portrait mode. (Oddly, they don’t all use it to know how to display photos on the screen.) But you can do much more. For example, you should be able to tell if the camera is on a tripod or handheld, based on how steady it is. That knowledge can be used to enable or disable the image stabilizer. It can also be used to add stability, by offering to delay the shutter release until the camera is being held steady when doing longer exposures. (Nikon had a feature called BSS, where it would shoot several long exposure shots, and retain the one that was least blurry. This should be a regular feature for all cameras.) Knowing the camera is stable on a tripod should also allow automatic exposure controllers to make more use of longer exposures if they need to in low light, though of course with moving subjects you still need manual control. (The camera should also be able to tell if the subjects are moving if it knows the camera itself is stable.)

Like new phones, also have a compass, and record the direction of all photos, to add to GPS data. This would allow identification of subjects. It would also allow “panorama” modes that know when you have rotated the camera sufficiently for the next overlapping shot. Finally, the accelerometer should offer me a digital level on the screen so I can quickly level the camera.

Embrace your inner eBook

I wrote about this last month — realize we are using cameras to do more than just take pictures.

Use the battery to power AC startup surge in an RV

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!

Anti-atrocity system with airdropped video cameras

Our world has not rid itself of atrocity and genocide. What can modern high-tech do to help? In Bosnia, we used bombs. In Rwanda, we did next to nothing. In Darfur, very little. Here’s a proposal that seems expensive at first, but is in fact vastly cheaper than the military solutions people have either tried or been afraid to try. It’s the sunlight principle.

First, we would mass-produce a special video recording “phone” using the standard parts and tools of the cell phone industry. It would be small, light, and rechargeable from a car lighter plug, or possibly more slowly through a small solar cell on the back. It would cost a few hundred dollars to make, so that relief forces could airdrop tens or even hundreds of thousands of them over an area where atrocity is taking place. (If they are $400/pop, even 100,000 of them is 40 million dollars, a drop in the bucket compared to the cost of military operations.) They could also be smuggled in by relief workers on a smaller scale, or launched over borders in a pinch. Enough of them so that there are so many that anybody performing an atrocity will have to worry that there is a good chance that somebody hiding in bushes or in a house is recording it, and recording their face. This fear alone would reduce what took place.

Once the devices had recorded a video, they would need to upload it. It seems likely that in these situations the domestic cell system would not be available, or would be shut down to stop video uploads. However, that might not be true, and a version that uses existing cell systems might make sense, and be cheaper because the hardware is off the shelf. It is more likely that some other independent system would be used, based on the same technology but with slightly different protocols.

The anti-atrocity team would send aircraft over the area. These might be manned aircraft (presuming air superiority) or they might be very light, autonomous UAVs of the sort that already are getting cheap in price. These UAVs can be small, and not that high-powered, because they don’t need to do that much transmitting — just a beacon and a few commands and ACKs. The cameras on the ground will do the transmitting. In fact, the UAVs could quite possibly be balloons, again within the budget of aid organizations, not just nations.  read more »

Authenticated actions as an alternative to login

The usual approach to authentication online is the “login” approach — you enter userid and password, and for some “session” your actions are authenticated. (Sometimes special actions require re-authentication, which is something my bank does on things like cash transfers.) This is so widespread that all browsers will now remember all your passwords for you, and systems like OpenID have arise to provide “universal sign on,” though to only modest acceptance.

Another approach which security people have been trying to push for some time is authentication via digital signature and certificate. Your browser is able, at any time, to prove who you are, either for special events (including logins) or all the time. In theory these tools are present in browsers but they are barely used. Login has been popular because it always works, even if it has a lot of problems with how it’s been implemented. In addition, for privacy reasons, it is important your browser not identify you all the time by default. You must decide you want to be identified to any given web site.

I wrote earlier about the desire for more casual athentication for things like casual comments on message boards, where creating an account is a burden and even use of a universal login can be a burden.

I believe an answer to some of the problems can come from developing a system of authenticated actions rather than always authenticating sessions. Creating a session (ie. login) can be just one of a range of authenticated actions, or AuthAct.

To do this, we would adapt HTML actions (such as submit buttons on forms) so that they could say, “This action requires the following authentication.” This would tell the browser that if the user is going to click on the button, their action will be authenticated and probably provide some identity information. In turn, the button would be modified by the browser to make it clear that the action is authenticated.

An example might clarify things. Say you have a blog post like this with a comment form. Right now the button below you says “Post Comment.” On many pages, you could not post a comment without logging in first, or, as on this site, you may have to fill other fields in to post the comment.

In this system, the web form would indicate that posting a comment is something that requires some level of authentication or identity. This might be an account on the site. It might be an account in a universal account system (like a single sign-on system). It might just be a request for identity.

Your browser would understand that, and change the button to say, “Post Comment (as BradT).” The button would be specially highlighted to show the action will be authenticated. There might be a selection box in the button, so you can pick different actions, such as posting with different identities or different styles of identification. Thus it might offer choices like “as BradT” or “anonymously” or “with pseudonym XXX” where that might be a unique pseudonym for the site in question.

Now you could think of this as meaning “Login as BradT, and then post the comment” but in fact it would be all one action, one press. In this case, if BradT is an account in a universal sign-on system, the site in question may never have seen that identity before, and won’t, until you push the submit button. While the site could remember you with a cookie (unless you block that) or based on your IP for the next short while (which you can’t block) the reality is there is no need for it to do that. All your actions on the site can be statelessly authenticated, with no change in your actions, but a bit of a change in what is displayed. Your browser could enforce this, by converting all cookies to session cookies if AuthAct is in use.

Note that the first time you use this method on a site, the box would say “Choose identity” and it would be necessary for you to click and get a menu of identities, even if you only have one. This is because a there are always tools that try to fake you out and make you press buttons without you knowing it, by taking control of the mouse or covering the buttons with graphics that skip out of the way — there are many tricks. The first handover of identity requires explicit action. It is almost as big an event as creating an account, though not quite that significant.

You could also view the action as, “Use the account BradT, creating it if necessary, and under that name post the comment.” So a single posting would establish your ID and use it, as though the site doesn’t require userids at all.  read more »

ClariNet history and the 20th anniversary of the dot-com

Twenty years ago (Monday) on June 8th, 1989, I did the public launch of, my electronic newspaper business, which would be delivered using USENET protocols (there was no HTTP yet) over the internet.

ClariNet was the first company created to use the internet as its platform for business, and as such this event has a claim at being the birth of the “dot-com” concept which so affected the world in the two intervening decades. There are other definitions and other contenders which I discuss in the article below.

In those days, the internet consisted of regional networks, who were mostly non-profit cooperatives, and the government funded “NSFNet” backbone which linked them up. That backbone had a no-commercial-use policy, but I found a way around it. In addition, a nascent commercial internet was arising with companies like UUNet and PSINet, and the seeds of internet-based business were growing. There was no web, of course. The internet’s community lived in e-Mail and USENET. Those, and FTP file transfer were the means of publishing. When Tim Berners-Lee would coin the term “the web” a few years later, he would call all these the web, and HTML/HTTP a new addition and glue connecting them.

I decided I should write a history of those early days, where the seeds of the company came from and what it was like before most of the world had even heard of the internet. It is a story of the origins and early perils and successes, and not so much of the boom times that came in the mid-90s. It also contains a few standalone anecdotes, such as the story of how I accidentally implemented a system so reliable, even those authorized to do so failed to shut it down (which I call “M5 reliability” after the Star Trek computer), stories of too-early eBook publishing and more.

There’s also a little bit about some of the other early internet and e-publishing businesses such as BBN, UUNet, Stargate, public access unix, Netcom, Comtex and the first Internet World trade show.

Extra, extra, read all about it: The history of and the dawn of the dot-coms.

Apple blocks iPhone App because EFF blog points to my Downfall Parody

Last week, I posted a pointer to my parody of a famous clip from the movie Downfall and I hope you enjoyed it. While the EFF itself didn’t make this video, I do chair the foundation and they posted a pointer to it on the “Deep Links” blog. All well and good.

Some time earlier, an iPhone app developer put together an iPhone app which would display the EFF blog feed. This wasn’t an EFF effort, but the EFF gave them permission to put the logo in the app.

Recently, Apple’s App Store team evaluated the app. The pulled up the EFF blog feed, and played the video, presumably using the built in YouTube playing App which Apple provides for the iPhone. And in the subtitles I wrote, at one point when Hitler was particularly angry, the fake text had him say “fucking.” This is quite mild compared to most of the Downfall parodies on YouTube, and indeed many other videos on YouTube. I debated taking it out, but it’s appropriate for the character to be using strong angry language at that point in his rant. And it’s funny to see Hitler swear in English so I left it in.

The App Store team — dare I call them the Apple App Store content Nazis, or is that too meta? — declared the app unsuitable for the iPhone store. Note that the app doesn’t contain any dirty words, and the EFF blog rarely contains them, and didn’t contain them in this case, only pointing to the video. Of course, the EFF as a free speech organization is not about to declare its blog will be free of bad words in the future, though they are a fairly unlikely event.

Yet this, it seems, is what Apple is protecting its users from. Apple claims that it needs to control what Apps you can install on an iPhone. You need to “jailbreak” the iPhone to install other apps, and Apple says you don’t have the right to do that. Sometimes such walled gardens start off with what you may agree are good intentions, such as stopping malicious apps, or assuring a quality experience with a product. But always, it seems, it devolves to this.

You can also read the EFF Deep Links article on this bizarre denial. Apple seems to have become a parody of itself. How long before we see a Downfall clip where Hitler is an Apple app store evaluator, or a fake Steve Jobs? Of course, that had better not contain any upsetting words, even in links.

Gallery of my favourite panoramas

While I have over 30 galleries of panoramic photos up on the web, a while ago I decided to generate some pages of favourites as an introduction to the photography. I’m way behind on putting up galleries from recent trips to Israel, Jordan, Russia and various other places, but in the meantime you can enjoy these three galleries:

My Best Panoramas — favourites from around the world

Burning Man Sampler — different sorts of shots from each year of Burning Man

Giant Black Rock City Shots — Each year I shoot a super-large shot of the whole of Black Rock City. This shows this shot for each year.

As always, I recommend you put your browser in full-screen mode (F11 in Firefox) to get the full width when clicking on the panos.

Hitler tries a DMCA takedown

New Update, April 2010: Yes, even this parody video has been taken down though the YouTube Content-ID takedown system — just as my version of Hitler says he is going to do at the end. I filed a dispute, and it seems that now you can watch it again on YouTube, at least until Constantin responds as well as on Vimeo. I have a new post about the takedown with more details. In addition, YouTube issued an official statement to which I responded.

Unless you’ve been under a rock, you have probably seen a parody clip that puts new subtitles on a scene of Hitler ranting and raving from the 2004 German movie Downfall (Der Untergang). Some of these videos have gathered millions of views, with Hitler complaining about how he’s been banned from X-box live, or nobody wants to go to Burning Man, or his new camera sucks. The phenomenon even rated a New York Times article.

It eventually spawned meta-parodies, where Hitler would rant about how many Hitler videos were out on the internet, or how they sucked. I’ve seen at least 4 of these. Remarkably, one of them, called Hitler is a Meme was pulled from YouTube by the studio, presumably using a DMCA takedown. A few others have also been pulled, though many remain intact. (More on that later.)

Of course, I had to do my own. I hope, even if you’ve seen a score of these, that this one will still give you some laughs. If you are familiar with the issues of DRM, DMCA takedowns, and copyright wars, I can assure you based on the reviews of others that you will enjoy this quite a bit. Of course, as it criticises YouTube as well as the studio, I have put it on YouTube. But somehow I don’t think they would be willing to try a takedown — not on so obvious a fair use as this one, not on the chairman of the most noted legal foundation in the field. But it’s fun to dare them.

(Shortly I may also provide the video in some higher quality locations. I do recommend you click on the “HQ” button if you have bandwidth.)  read more »

Making of the Video, Legally

On ultralight vehicles vs. large mass transit vehicles

One of the questions raised by the numbers which show that U.S. transit does not compete well on energy-efficiency was how transit can fare so poorly. Our intuition, as well as what we are taught, makes us feel that a shared vehicle must be more efficient than a private vehicle. And indeed a well-shared vehicle certainly is better than a solo driver in one of todays oversized cars and light trucks.

But this is a consequence of many factors, and surprisingly, shared transportation is not an inherent winner. Let’s consider why.

We have tended to build our transit on large, heavy vehicles. This is necessary to have large capacities at rush hour, and to use fewer drivers. But a transit system must serve the public at all times if it is to be effectively. If you ride the transit, you need to know you can get back, and at other than rush hour, without a hugely long wait. The right answer would be to use big vehicles at rush hour and small ones in the off-peak hours, but no transit agency is willing to pay for multiple sets of vehicles. The right answer is to use half-size vehicles twice as often, but again, no agency wants to pay for this or to double the number of drivers. It’s not a cost-effective use of capital or the operating budget, they judge.


The urban vehicle of the future, as I predict it, is a small, one-person vehicle which resembles a modern electric tricycle with fiberglass shell. It will be fancier than that, with nicer seat, better suspension and other amenities, but chances are it only has to weigh very little. Quite possibly it will weigh less than the passenger — 100 to 200lbs.

Transit vehicles weigh a lot. A city bus comes in around 30,000 lbs. At its average load of 9 passengers, that’s over 3,000lbs of bus per passenger. Even full-up with 60 people (standing room) it’s 500lbs per passenger — better than a modern car with its average of 1.5 people, but still much worse than the ultralight.  read more »

Can airports do paging as well as a restaurant?

I have a lot of peeves about airports, like almost everybody. One of them is the constant flow of public address announcements. They make it hard to read, work or concentrate for many people. Certainly it’s hard to sleep. It’s often even hard to have a phone call with the announcements in the background.

One solution to this is the premium airline lounges. These are announcement-free, but you must watch the screens regularly to track any changes. And of course they cost a lot of money, and may be far from your gate.

Some airlines have also improved things by putting up screens at the gates that list the status of standby passengers and people waiting for upgrades. This also saves them a lot of questions at the gate, which is good.

But it’s not enough. Yet, even in a cheap restaurant, they often have a solution. They give you a special pager programmed to summon you when your table or food is ready. It vibrates (never beeps) and they are designed to stack on top of one another for recharging.

Airports could do a lot better. Yes, they could hand you an electronic pager instead of/in addition to a boarding pass. This could be used to signal you anywhere in the airport. It could have an active RFID to allow you to walk though an automatic gate onto the plane with no need for even a gate agent, depositing the pager as you board.

Each pager could also know where it is in the airport. Thus a signal could go out about the start of boarding, and if your pager is not at the gate, it could tell the airline where you are. If you’re in the security line, it might tell you to show the pager to somebody who can get you through faster (though of course if you make this a regular thing that has other downsides.)  read more »

Electronic panorama head with rotation sensor

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.

Allow a refund on prepaid cell service for tourists

Years ago I asked that they let me buy a SIM card in the airport arrivals area and now they often do. I also started a forum here on the best company to buy a prepaid SIM from in each country which has a fair bit of traffic.

And indeed, I have been doing that, because often roaming rates remain obscene. I dropped my Canadian SIM when Sprint offered a plan with 20 cent/minute roaming in Canada that I can turn on for $3/month — this was comparable to the prepaid price I was getting, and prepaid had the “overhang balance” problem I will discuss below. But I’ve gotten or been loaned local SIMs in several countries to good use — especially when both I and my travel companion have one so we can use our cell phones as radios.

But a few problems exist with getting a local SIM. First, you have to get one. The cheapest place to do this is usually the local cell phone shops that can be found in most urban shopping areas. If you plan ahead, you can get one mailed to your hotel, though the companies that do this which aim at tourists always overcharge — perhaps enough to wipe out your savings if your call volume is modest or your stay short. The ideal SIM is near-free, and can be found where you enter the country.

Next, you must fill the account. Almost everywhere, you must use prepaid cards bought for cash from the shops, as they will not let you fill, or refill, with an out-of-country credit card, for supposed security reasons. This is annoying because you don’t want to have a large balance remaining (overhang) on your prepaid account when you leave the country, unless you will be back before it expires. (Sometimes you can use it up in other countries with obscene roaming rates, but often not even then.) But you also don’t want to have to risk running out of minutes in the middle of a call.

The answer: Let me put a fat balance on my prepaid account, and let me refund all or most of it when I am done — ideally back to my credit card when I leave.

The cell company loses that wasted balance, sure, but instead, I am prone to use the phone more if I have a large enough balance and a good enough rate that I don’t have to worry. I will use it like a local. This would be a good competitive edge that would make the difference if I were buying a SIM. You could offer this only to people from out of the country but I see no reason not to offer it to local users too.

Yes, processing the refund has a small cost. If you insist, don’t refund the last few bucks to cover your costs. Or alternately, let me do “minutes transfer” to other prepaid users. Then I could meet somebody (or go into a shop) and transfer the minutes and get cash for them.

Of course, it would also be nice if you would let me just buy a monthly plan deal for just one month, with no contract. Cell companies seem loathe to do this, but T-Mobile in the USA has just started doing exactly that with their flex-pay. In that system you pre-pay for one month of any monthly plan, and if you think you will use more than the minutes on that plan, you can put money into an overage account. But you can’t get it back, so that’s one modification to add. But frankly I would probably never go over the monthly plan I bought in a typical trip.

The remaining big headache is data. Getting a prepaid plan with data at a decent price (or any data at all) can be hard. Those from the USA are used to unlimited data, which they resist selling in many countries. Those from the USA who bring their phones overseas and forget to turn off roaming data often find nightmare bills of many thousands of dollars. The world has to figure this out. Still, those who are used to fancy network PDA phones often find themselves literally lost without their Google Maps Mobile or their e-Mail. We need a way to roam data selectively, letting some apps use limited data budgets but preventing others if we can’t get a decent data price plan. E-mail apps can go into low-data move (never download attachments or long messages automatically, just imap headers) and less frequent checking. If one is careful, one can get something decent at the $2/megabyte (or $10/megabyte) crazy prices for mobile data roaming.

Oh yeah, and think about doing 2-SIM offers to tourists, who often arrive in pairs. Especially if they include cheap mobile-to-mobile calling in the pair.

Virgin America Airways and on-demand ordering

Yesterday I took my first flight on Virgin America airways, on the IAD-SFO run. Virgin offered a tremendous price (about $130 one way) but it’s worth examining how they have made use of technology on their planes. Mostly I usually end up on United, which is by far the largest carrier at SFO. Because of this, I fly enough on it to earn status, and that it turn provides a seat in their Economy Plus section which has more legroom, priority boarding and in theory, an empty middle if there are empty middles. This is 90% of the value of the status — the other main value, ability to upgrade, is hard to actually make use of because business class is usually full. The extra legroom is surprisingly pleasant, even for a widebody individual like myself who would much prefer extra width if I had a choice.

Other than Economy Plus (and some very nice business class on some of the long-haul planes,) United is falling behind other airlines. It would be hard to recommend an ordinary coach seat. The one big amenity that more and more other airlines are providing is power in coach, in particular 115v AC power which is more flexible than the older 15vdc “Empower” system United uses in business class. The main downside of the 115v connections is they tend to be mounted under the seats, making them hard to get to. Air Canada has put them in the personal video panels. Virgin placed them under the seats but high and forward enough to be reached (if you knew what you were looking for) but also so close as to make wall-warts bump against your legs. Virgin also offered USB jacks down under the seats, also hard to get to. Even if you don’t want to put 115v up higher, USB charging jacks are better placed in the video console/seatback I think.

American Airlines has a mix of DC and AC power, but still makes it available in coach. Continental has put EmPower on some planes in the front half of coach, but some newer planes have AC power all the way through coach.  read more »

Two sources on energy, and using heat

I was reminded yesterday, after posting more on the cost-effectiveness of energy sources, to point out an interesting new book on the economics of energy. The book is Sustainable Energy With the Hot Air by David MacKay, a physics professor from Cambridge University. What’s important about the book is that he pays hard attention to the numbers, and demonstrates that certain types of alternative energy are likely to never make sense, while others are more promising.

I only have a few faults to pick with the book, and he’s not unaware of them. He decides to express energy in the odd unit of “kilowatt-hours per day” as he feels this will make numbers more manageable to the reader. Of course with time in the numerator and denominator, it’s a bit strange to the scientist in me. (It’s the same as about 42 watts.) In a world where we often see people say “kilowatt” when they mean “kilowatt-hour” I suppose one deserves credit for using a correct, if strange unit.

My real quibble is over his decision to measure energy usage at the tank, so that an electric car’s energy usage is measured in the battery, while a gasoline car is measured in the fuel tank. Today we burn fuel to make electricity, and so electric cars actually consume 3 times the energy they put in the batteries. That’s a big factor. MacKay argues that since future energy sources (such as solar) might generate electricity without burning fuel, that this is a fair way to look at it. This is indeed possible but I think it is necessary to look at it both ways — how efficient the vehicles are today (and will be if we still generate electricity from heat) and how they might be in the future. Generating electricity from heat does complicate the math of energy in ways that people can’t agree on, so I understand his temptation.

Yesterday I was also pointed out to a solar power site called SolarBuzz. This is a pro-solar-panel site, and is rare in that it seems to do its math right. I haven’t looked at all the numbers, and I am surprised wthat with the numbers they show that they are such boosters. Their charts of payback times all focus on power costs from 20 to 50 cents/kwh. Those costs are found in Europe, and in the tiers of California, but the U.S. national average is closer to 10 cents, where there is no payback. They also use 5% for their interest rate, a low rate that is only found in strange economic times such as these — but justifiable in a chart today.  read more »

Pure heating is highly wasteful

Is being evangelical about solar the right course?

The earlier post on whether solar gives the best bang per buck in greening our electricity ran into some opposition, as I expected. Let me consider some of the objections and issues.

As a recap, I put forward that if we are going to use our money and time to attain greener electricity, what matters is how many MWH we take off the “dirty” grid (particularly coal plant output.) I measured various ways to do that, both green generation and conservation (which do the exact same thing in terms of grid offset) and worked out their cost, the MWH they take off the grid and thus the cost per MWH. Solar PV fares poorly. Converting incandescent bulbs to fluorescent in your own home or even other people’s homes fares best.

A big part of the blame lies on the fact that crystalline silicon is an expensive way to make solar cells. It is, however, quite common since many PV plants started with technology from semiconductor fabrication.

Evangelical green

One frequent objection is that purchasing expensive solar panels today encourages the market for solar panels, and in particular better solar panels. Indeed, panel makers are generally selling all they can make. Many hope that this demand will encourage financing for the companies who will deliver panels at prices that make sense and compete with other green energy.

I call this being “evangelical green.” Leading by example, and through encouraging markets. While I understand the logic, I am not sure I accept the argument.  read more »

Proposition T: All ballot propositions must fit in 140 characters

I was reviewing the voter information guide for the upcoming California Special Election. Even though I can’t vote it is interesting to look at the process. To my surprise, the full text of the propositions shows the real items to be incredibly complex. Proposition 1C, which updates lottery laws, is over 4 1/2 pages of dense print.

There is simply no way one could expect the electorate to make informed choices on constitutional changes like these. These are closer to the “Click to agree” contracts on a piece of software from the RIAA.

In this case, all the propositions were written by the legislators themselves, in response to a budget crisis. They want a bunch of constitutional changes that are outside their own power, but they have written them like legislative bills. (Well, frankly, those are even longer than a few pages.) The public gets a book with analysis (itself many pages long) and arguments and rebuttals by those on the for and against side. They get bombarded with ads on any proposition that has strong financial backers or opponents, usually propositions that involve lots of money.

So no, while I don’t really think you can fit every amendment into the size of a twitter post, there should be a size limit. If complex things need to be done, a shorter, understandable initiative should give the legislature the minimum powers it needs to do it — perhaps even temporarily. Watchdogs will examine just how much power this really is and warn about it, one hopes.

This isn’t the only type of legislator trick. The most common one, in fact, is the “bond measure.” Frequently on the ballot we will see authorization for the state to borrow money (issues bonds) for some sort of motherhood issue. For example, they will ask for billions to “fix levees in flood zones” or “fund libraries.”

Of course, they were going to fix the levees anyway. They were going to fund education anyway. There is no way they couldn’t. By issuing the bond, they don’t have to find room in the general fund for those things, allowing them to spend general fund money on something the public would never vote for. So instead of asking the public to fund tropical retreats for legislators, they ask the public to fund libraries, leaving the money that would have funded libraries to pay for the tropical retreat.

How do we stop this, short of removing public participation? I think a more reasonable limit (like 2,000 characters — about 400 words) might help a bit. And while bond measures may be sometimes needed, it might make sense to require that for the legislators to put a bond measure on the ballot, it must be something which they themselves voted against doing from the general fund. Then the minority who voted for it could ask to put it on the ballot. What this would mean is that before they could put library funding as a bond measure, they would have to have gone on record voting against library funding. I don’t know if this would be enough, though and perhaps a stronger method is needed. Of course, the bonds mean taxes must go up in the future to pay them back. (Or, they hope, tax revenues go up due to a growing economy, so tax rates don’t have to rise, as they know they will never get approval for that.)

What’s a way to make this work better and stop these abuses?

When the cell phone rings...

We’ve all experienced it. A cell phone starts ringing or vibrating. To be clever, it slowly starts getting louder in case the owner didn’t hear or feel the initial signal. You see somebody going through their bag looking for the phone that keeps getting louder and louder. Finally they answer and it shuts up.

Yet today’s new phones are all featuring accelerometers. This gives them to chance to know we are fumbling for them. Yes, if you’re out jogging it won’t be able to spot the new level of activity in fetching out the phone, but if you’re sitting in a quiet room, and the phone’s been still and it starts moving about shortly after starting ringing, the phone can know you’re aware of the ring, and start getting quieter. (It might switch back to vibrating or flashing to help you find it.) A ringing phone could also be listening to its microphone, and waiting for you to say commands to it, such as “getting it” to “voicemail” to “speaker” rather than have you hunt for the button. How often has a call gone to voicemail before you could find that button? When you are getting it, the phone could answer (to avoid going to voicemail) and then play a message to the caller about how you are still getting the phone and will be with them shortly. If you can hear the phone, it can hear you.

In fact, phones need to understand more when they are sitting on tables or on our persons. Movement is one way to know this. Temperature is another. Capacitance is a third. Hearing “master’s voice” in the microphone reveals something else, like the fact you’re in a meeting. Is the conversation half-duplex? You may be on a landline. Many phones know when they are being charged and change their ring behaviour. They can do more.

And here’s a second feature for cell phones ringing in the home or office. Let the customer, at that moment, call a special magic number from a prearranged land-line. This number would be put in the speed dial of the land-line, and the land-line would send caller-ID. A call to that number would grab the call going into the cell phone and transfer it to the land line. Ideally the cell phone company would bill these minutes at a lower rate, though I doubt it, since they don’t do that for call forwarding set up in advance. This is call grabbing, the way many PBXs can do.

For security there would be a bank of 100 numbers arranged for the purpose. A stranger could not grab your calls unless they knew which of the 100 numbers is the one for you on that landline. Many false attempts would disable the feature, which would be a form of DOS attack but not a very exciting one, as you can just grab the cell phone in that case.

For the user, the UI is simple. You hear your cell phone ringing in the charging station. You pick up a land line, hit a speed dial, and it answers and you are connected.

Of course, the real answer is that phones should never ring at all in most situations.

Connecting untrusted devices to your computer

My prior post about USB charging hubs in hotel rooms brought up the issue of security, as was the case for my hope for a world with bluetooth keyboards scattered around.

Is it possible to design our computers to let them connect to untrusted devices? Clearly to a degree, in that an ethernet connection is generally always untrusted. But USB was designed to be fully trusted, and that limits it.

Perhaps in the future, an OS can be designed to understand the difference between trusted and untrusted devices connected (wired or wirelessly) to a computer or phone. This might involve a different physical interface, or using the same physical interface, but a secure protocol by which devices can be identified (and then recognized when plugged in again) and tagged once as trusted the first time they are plugged in.

For example, an unknown keyboard is a risky thing to plug in. It could watch you type and remember passwords, or it could simply send fake keys to your computer to get it to install trojan software completely taking it over. But we might allow an untrusted keyboard to type plain text into our word processors or E-mail applications. However, we would have to switch to the trusted keyboard (which might just be a touch-screen keyboard on a phone or tablet) for anything dangerous, including of course entry of passwords, URLs and commands that go beyond text entry. Would this be tolerable, constantly switching like this, or would we just get used to it? We would want to mount the inferior keyboard very close to our comfy but untrusted one.

A mouse has the same issues. We might allow an untrusted mouse to move the pointer within a text entry window and to go to a set of menus that can’t do anything harmful on the machine, but would it drive us crazy to have to move to a different pointer to move out of the application? Alas, an untrusted mouse can (particularly if it waits until you are not looking) run applications, even bring up the on-screen keyboard most OSs have for the disabled, and then do anything with your computer.

It’s easier to trust output devices, like a printer. In fact, the main danger with plugging in an unknown USB printer is that a really nasty one might pretend to be a keyboard or CD-Rom to infect you. A peripheral bus that allows a device to only be an output device would be safer. Of course an untrusted printer could still record what you print.

An untrusted screen is a challenge. While mostly safe, one can imagine attacks. An untrusted screen might somehow get you to go to a special web-site. There, it might display something else, perhaps logins for a bank or other site so that it might capture the keys. Attacks here are difficult but not impossible, if I can control what you see. It might be important to have the trusted screen nearby somehow helping you to be sure the untrusted screen is being good. This is a much more involved attack than the simple attacks one can do by pretending to be a keyboard.

An untrusted disk (including a USB thumb drive) is actually today’s biggest risk. People pass around thumb drives all the time, and they can pretend to be auto-run CD-roms. In addition, we often copy files from them, and double click on files on them, which is risky. The OS should never allow code to auto-run from an untrusted disk, and should warn if files are double-clicked from them. Of course, even then you are not safe from traps inside the files themselves, even if the disk is just being a disk. Many companies try to establish very tight firewalls but it’s all for naught if they allow people to plug external drives and thumbsticks into the computers. Certain types of files (such as photos) are going to be safer than others (like executables and word processor files with macros or scripts.) Digital cameras, which often look like drives, are a must, and can probably be trusted to hand over jpegs and other image and video files.

A network connection is one of the things you can safely plug in. After all, a network connection should always be viewed as hostile, even one behind a firewall.

There is a risk in declaring a device trusted, for example, such as your home keyboard. It might be compromised later, and there is not much you can do about that. A common trick today is to install a key-logger in somebody’s keyboard to snoop on them. This is done not just by police but by suspicious spouses and corporate spies. Short of tamper-proof hardware and encryption, this is a difficult problem. For now, that’s too much cost to add to consumer devices.

Still, it sure would be nice to be able to go to a hotel and use their keyboard, mouse and monitor. It might be worth putting up with having to constantly switch back to get full sized input devices on computers that are trying to get smaller and smaller. But it would also require rewriting of a lot of software, since no program could be allowed to take input from an untrusted device unless it has been modified to understand such a protocol. For example, your e-mail program would need to be modified to declare that a text input box allows untrusted input. This gets harder in web browsing — each web page would need to have to declare, in its input boxes, whether untrusted input was allowed.

As a starter, however, the computer could come with a simple “clipboard editor” which brings up a box in which one can type and edit with untrusted input devices. Then, one could copy the edited text to the OS clipboard and, using the trusted mouse or keyboard, paste it into any application of choice. You could always get back to the special editing windows using the untrusted keyboard and mouse, you would have to use the trusted ones to leave that window. Cumbersome, but not as cumbersome as typing a long e-mail on an iPhone screen.

Powered USB Hub in my hotel room, and more

What should be in a good hotel room?

Well, one thing that’s easy to add to the list is a powered USB hub, with as many as 6 ports and a 3 amp power supply. Toss in some mini-USB cables (possibly just built into the hub) as they have become, for better or worse, the present-day universal charging standard. (At only 2.5 watts, USB is a bit anemic as charging standard, but it’s what we have for now.) A mouse would be nice too, but is a security risk.

Alas, we can’t have a keyboard on it, as nice as that would be, since that can’t be trusted. It might have a keylogger put in it (even by the previous occupant of the room) to grab passwords.

Now this is a fairly cheap item (under $20) and like many other hotel items, it could also be available at the front desk, though it’s so cheap I don’t see a reason for that. While you could not be sure it would be there at every hotel, it would still be useful, since it can add to the charging you bring, and most laptops can be a charging station if you are willing to leave them on overnight. It’s also useful as a hub. Indeed, have two, one on the desk, and one by the bed for cell phones.

We’re almost ready to not need the hotel phone unless you are coming from overseas and pay ridiculous roaming charges. But they still need it to call you sometimes, and I don’t want to have to hand over my mobile number at check-in.

Most hotel rooms now are getting a flat-screen HDTV. That’s great, but rarely do they offer up the VGA port that many of these TVs have, or a cable to plug it in. I recommend a 1080p TV for each room, located in such a way that it can be an external monitor for my laptop. As such there should be a VGA cable connected or handy. The TV could also be connected to the USB hub, and use a video over USB protocol for devices that have USB out but not video out. (This usually needs a driver and has some limitations.)  read more »