Author Archives: Jonathan

About Jonathan

Asst. Group Leader in aerospace at MIT Lincoln Laboratory.

How to rotate iPhone video on a Mac

I ran into what is apparently a not uncommon problem with iPhone video: you start to take a video while phone still thinks it’s in portrait orientation (long axis of the phone vertical) and then the rest of the video is stuck that way, even if you took 99% of it in landscape mode (the way God intended). You thus have a video that the Mac always wants to display sideways. If that didn’t make any sense, the bottom line is I had a video I needed to rotate 90 degrees, and maybe you do, too. While there were plenty of solutions available on the PC, tons of Googling turned up virtually nothing for the Mac, short of finding an old copy of iMovie from five years ago.

Fortunately, I lucked in to a great solution, which doesn’t even require transcoding (with the attendant loss in quality that would result). By the way, this worked for me in getting a video from portrait to landscape, and I suspect it may only work in that situation. (That said, this should be the only valid situation in which this problem occurs, as nobody in their right mind should ever shoot a video in portrait mode, and if you do, I’m certainly not going to be complicit in aiding and abetting that crime against humanity.)

The solution requires a copy of the very nice all-purpose video player, VLC.

  1. Open the video in VLC
  2. It should actually open up in landscape orientation, regardless of the erronious orientation data in the movie file from the iPhone.
  3. Select “Streaming/Exporting Wizard” from the File menu.
  4. Select “Transcode/Save to file” and click next.
  5. Use “Existing Playlist” and select the file you just opened below, click next.
  6. Leave everything untouched (i.e. both check boxes blank) on the transcode screen and click next.
  7. Choose MPEG4, click next.
  8. Click the button to tell VLC where to put the output file, then click next.
  9. Click finish.

This should be all it takes. The process will be fairly quick, since there’s no transcoding, but its not instantaneous as it does have to move a lot of bits into a new file.

Proof you’re a parent

For some reason I decided to take a look at the top 50 most played songs on my iPod. Here they are, listed from 5 to 1.

Rank Title               Artist             Number of Times Played
5.   Many the Miles      Sara Bareilles     66
4.   Fireflies           Owl City           67
3.   The Wider Sun       Jon Hopkins        81
2.   Baby Monkey         Parry Gripp        322
1.   Oatmeal             Parry Gripp        393

One guess as to which two songs are Alex’s favorites?

Hypothesis testing proves ESP is real

Or maybe it would be more accurate to say that ESP proves frequentist statistics isn’t real. In what has got to be one of the best object lessons in why hypothesis testing (the same statistical method usually used by the medical research industry to produce the Scare of the Week) is prone to generate false results, a well-respected psychology journal is set to publish a paper describing a statistically significant finding that ESP works.

The real news here, of course, is not that ESP has been proven real, but that using statistics to try to understand the world is a breeding ground for junk science. If I had to guess, I’d say the author (who is a well-respected academic who has never published any previous work on ESP) has had a case of late-career integrity and has decided to play a wonderful joke on the all-too-deserving field of psychology by doing a few experiments until obtaining statistically meaningful results that defy everything we know about the universe. As I’ve pointed out before, one of the many problems with hypothesis testing is that you don’t have to try all that hard to prove anything, even when done “correctly,” given that nobody really keeps track of negative results.

Finally, a good Subversion client for Mac OS X

If you don’t have a Mac, or don’t know what SVN is, please accept my apologies for this very directed post. To the one guy remaining, rejoice:

For the longest time, there has been no good SVN interface available on the Mac. Windows folks had TortoiseSVN, and Linux folks wouldn’t be caught dead using anything other than command line tools (or, git, for that matter). So, everybody was happy but us Mac folks.

A program called “Versions” has been available for a while, but it, sadly, epitomizes the style over substance sin that is so prevalent on the Mac. It’s got a beautiful interface, but it’s an interface to very little. Namely, it doesn’t support merging or branching, which is pretty much the most important reason for using a versioning system like SVN. If you’re not branching and merging, you might as well just use a good backup system, because that’s pretty much all you’re using SVN for at that point.

So, I was very excited to find “Cornerstone,” which was recently upgraded to support the slickest SVN interface I’ve seen on any platform. It’s as pretty as “Versions” and as powerful (if not moreso) than TortoiseSVN. It’s merge facility is the best approach I’ve seen, for example. It’s intuitive, and as you adjust the settings it automatically performs a trial merge and gives you the results in real time. Awesome.

They have a two-week trial, which is more than enough to get a feel for the product, it’s so simple and well-executed.

(By the way, they aren’t giving me anything for this. I wish they were, but I don’t have that kind of juice.)

Getting the most data speed out of your cell phone

You may have noticed there have been very few posts here. There’s a reason for that. The first and foremost is that sending my rants in to the void has not been as personally cathartic as I’d hoped. My other goal for the blog, which actually has been somewhat successful, was to simply provide a vehicle for putting information out on the web that I thought might be useful for people, and that I couldn’t find elsewhere. Based on the traffic stats, those posts have actually been worthwhile, and my only reason for not doing more of this kind of post has been that I’ve been too busy playing with my son, finishing up my projects at MIT, and trying to get a job (in that order).

So, going forward, I’m just going to focus on the second category of posts (though I reserve the right to devolve to the first occasionally). This blog was getting too negative, anyway. In that spirit, here’s a particularly useful trick I just figured out while sitting in a coffee shop working remotely.

I recently gave up my nice window office since I was feeling guilty about taking up a nice spot but only working part time. So, I’ve been doing a lot of work remotely, usually from a coffee shop given that working at home just isn’t very productive when there’s an adorable toddler running around begging to be hugged. So, I splurged and decided to start paying the extra $20 a month to use my phone as an internet connection for my computer. This is becoming a pretty common thing, and Sprint even offers phones that will create a WiFi network on the fly (I use Bluetooth with my iPhone). I expect this will become even more common once the iPhone hits Verizon, as Apple will reportedly allow this version of their phone to create WiFi hotspots, too.

I would typically just leave my phone laying flat on the table next to my laptop. However, giving it a minute of thought, this is actually pretty dumb, for two reasons. First, having the phone so close to the laptop is probably not smart, as computers are notorious spewers of electromagnetic interference at pretty much every frequency imaginable. In theory, they should be shielded, but nothing is perfect and between the memory data rates and the processor clock speeds, a computer pretty much has the cell phone spectrum covered directly, if not with overtones. So, keep the cell phone away form the computer at least a foot or so.

Most importantly, however, leaving the cell phone flat on a table is a bad idea because it puts the antenna horizontal, whereas cell phone signals are polarized vertically. (What this means, if you’re not a fan of electromagnetics, is that the electrons in the cell phone tower antenna are being shaken up and down, not side-to-side. Radio waves are really just a way of keeping track of how electrons interact with each other. Without anything interfering, the electrons in your cell phone’s antenna will be wiggled in the same orientation and frequency as those in the cell tower antenna. However, antennas are designed for their electrons to be wiggled in a certain direction (it’s almost always along the long axis of the antenna) and a cell phone’s antenna is oriented with the assumption that the user is holding it upright against their ear.) Once I realized this, I put my phone up against a nearby wall so that it was standing straight up and down (as if somebody were holding it) and my data rates nearly doubled.

So, if you’re using your cell phone as an internet connection, keep it a bit away from the computer and prop it up so it’s vertical. Keeping it vertical in your pocket probably isn’t a great idea, since your body is pretty good at blocking radio. If you find this helps, please let me know in the comments. Right now my experience alone isn’t very statistically significant, to say the least.

Why you should stick with AT&T if you have an iPhone

It was just announced that Apple will finally port the iPhone over to Verizon’s network early next year. The conventional wisdom being that AT&T is an incompetent foil to Apple’s engineering genius, the only thing holding back the iPhone from true greatness, virtually everybody I know with an iPhone (and many waiting) say that they can’t wait until they can get a Verizon iPhone.

Let me pour a little rain on this parade. I’m tempted to say nothing (and let’s be honest, writing on this blog is pretty close to doing just that) because I’d love to have everybody run away to Verizon to clog up their network while those of us staying with AT&T enjoy the highest speeds we’ve ever seen. However, I suspect anybody moving from AT&T to Verizon will be sorely disappointed, for a few reasons.

First, it’s now widely acknowledged that the reception problems with the iPhone 3G, and to some extent the iPhone 4, are entirely the fault of Apple. It’s pretty clear from comparisons with AT&T network performance on other brands of phones versus the iPhone that Apple had a lot of learning to do about writing baseband wireless software. Apparently making a good cell phone is more than just sourcing a few million chips from Infineon and then treating the rest of the phone like a small laptop. Apple was way behind on the RF engineering needed to make a reliable cell phone. Even now, this is evident in the poor (albeit improved) performance of the iPhone 4, which can’t seem to figure out how to keep connected to a good signal and requires frequent cycling of the wireless chip to maintain a good connection. So, unless you live in an area just not well-served by AT&T, you will likely find slower speeds on Verizon. While Verizon does cover more physical space with their network, AT&T’s network is provably faster where it actually exists.

The above brings me to the second point: if Apple had a bit of a learning curve to figuring out how to write firmware for a GSM phone, it stands to reason they might have a few initial hiccups with a CDMA phone. Verizon’s network operates on a fundamentally different standard than AT&T’s, and Apple will be using wireless chips from a different company (Qualcomm) in their Verizon-compatible phones going forward. Given Apple’s propensity to punish the hell out of early adopters, and having paid my dues in that regard, I have no intention of seeing how they manage to screw up connectivity to Verizon’s network.

Finally, if the problem really is, to some extent, AT&T being overloaded by iPhone users, it would seem to me that the last thing you want to do is be part of the stampede over to Verizon. Just as things are finally speeding up for us sticking with AT&T, the poor existing Verizon folks will be waiting to check their e-mail as millions of iPhone users clog their networks. Verizon’s network may be the biggest, but my guess is that users in major cities will find out that biggest and fastest are two completely different things.

You can send me my check now, AT&T.

Google saves the world five seconds at a time

Google just announced new technology that will cause search results to be predictively presented to the user as they type each letter of their search, saving the user from having to type their entire search, or hit enter after each search. According to Google’s Vice President, this will save the user an average of “two to five seconds…” from each search. This is what they have been working on as their next generation of search. It’s impressive, to be sure.

But does it strike anyone else as odd that we, as a society, are putting our technological efforts and resources into developing technologies that save us seconds each day when we can’t, as a society, get it together to develop infrastructure and transportation technology that will save us hours from commuting? It seems perverse that most Google engineers probably sit in California traffic for over an hour each day so that they can come into work and make sure nobody has to wait more than 15 seconds for a search result.