Saturday, July 30, 2011

The sorry state of the computer display industry

Image by Derek K. Miller

This is going to be another sad commentary in a long long succession of commentaries about why computer displays haven't gotten much better over the years.  The last flurry of articles I read were written about four years ago in 2007.  I'm sorry to report that things haven't gotten any better.

First, the good news.  Monitors have gotten very large and very cheap since 2007.  I recently purchased a 23" monitor for $130 and I was surprised how generally good it was given the price point. Using as a reference I found good monitors in their top seller list for the following price points:

  • 21" - $117
  • 22" - $130
  • 23" - $140
  • 24" - $179
  • 25" - $259
  • 27" - $260
  • 30" - $299
So what's wrong with the computer monitor industry other than they can't be making very high margins with these prices?  The problem is all of these monitors run at a resolution of 1920x1080.  That is the same resolution your HDTV uses but labeled 1080p for the number of vertical pixels.  While 1080p has only become the standard TV resolution in the last 3 years, computer monitors have been commonly running this resolution and higher for the last 15 years.  As computer displays have become larger, the resolution hasn't changed very much or at all.  It's been long enough and it's way past time that computer displays get the same hi-def upgrade that TVs received.

The first part of the upgrade has arrived.  No one enjoyed having a 15" or 17" monitor.  Today it is almost not worth considering anything under 23" unless you have a specific space constraint.  I'm not sure I could get used to a 30" monitor or if I could I don't believe I would want an even larger display.  At some point making the monitor bigger causes you to have to start looking left and right and becomes a problem.  So monitor sizes have reached their apex or near enough.

The problem with making the display bigger while not increasing the resolution has the negative side effect of lowering the pixels per inch(ppi).  This causes a lot of problems such as blocky pixelated text.  Operating systems use complex technologies like clear text and anti-aliasing to hide these effects but there is only so much they can do.  These too cause problems such as fuzzy or blurry text.  Instead of using complex font rendering technologies, the real solution is to increase the resolution above 1920x1080.  However, monitor manufactures don't seem interested in doing this.

The monitors in the example above all run between 102ppi(21") and 73ppi(30").  If you want a 30" monitor that does 100ppi you have to pay $1200 or more.  95% of the monitors offered on NewEgg are models that have less than 102ppi. Only about 10 monitors offered greater than 102ppi and the prices are staggering. 
Below is a graph of all the monitors offered on  For each price range I counted how many monitors were listed for sale.  The number of monitors offered is inflated for the right side of the chart starting at $700 to keep the chart size reasonable and because there were no monitors offered in some rangesOnly monitors from NewEgg were included.  You can find models for slightly less than $1000 elsewhere that have higher than 100ppi.
Number of monitors on by price
Notice how few monitors there are above $300.  That is where the low end 130ppi to 200ppi monitors should be.  The 130ppi models offered are all above $1200 and are high end displays focused on very good color reproduction as well as high ppi.  The $400-$1200 monitors are 100ppi monitors with the same high quality color reproduction.  A high ppi monitor with normal color quality simply isn't available.

Why is the industry stuck at 1080p?  It's because consumers don't want their text and images to get smaller and harder to read.   Every time I walk into someones office and see them running a 27" or 30" monitor at 1280x900 I just want to claw my eyes out.  I can see the pixels from across the room.  The stair stepped pixels on A's look like I could climb them with size 12 boots.  Do people like reading fonts that look like they were drawn on graph paper?  No, but they don't have a better solution to make text larger.  If you are running a Windows OS, which most of us are, and you try to increase the font size a lot of applications break and behave badly. If, however, you run Linux or OSX you can simply increase the size of your default font and get beautiful crisp type the size of your fist if that's what you need.  Most Apple consumers purchase Apple monitors and the Linux install base is too small to create any demand from manufactures to improve.

The other major road block is the video connector, DVI,  which is the standard connector on all PC computers.  DVI was horribly handicapped from conception and is probably the single biggest reason nothing has changed.  It's limited to a maximum resolution of just over 1080p.  You can run monitors with higher resolutions but you need to use what is known as a dual-link DVI.  This doubles the supported resolution to 3840x2400 or 150ppi on a 30" monitor. The problem is almost no computers come with dual-link DVI ports.  You must typically add a discrete add-on graphics card to your computer to be able to run these high resolution displays. I contacted Dell about which laptop models supported dual-link DVI and only their ultra high-end Alienware line did and only if you upgraded to at least the 1.5GB Nvidia 460m graphic card.  Total system cost $1600 with no other upgrades.

So it seems we're doomed to another 4 years of staring at pixels, unless that is...

Unless you own or plan to own certain Apple products. In 2007 Apple launched the iPhone with a 480x320 165ppi screen.  Last year Apple released the iPhone4 with a 960x640 screen at 330ppi.  There are strong rumors that they will launch the iPad 3 in the 4th quarter of 2011 with a 2560x1920 screen at 284ppi. So this year you might be able to purchase a 9.7" Apple iPad 3 that will run a higher resolution than every consumer computer display of any size.  This includes Apple's own 27" Cinema display which runs at 2560x1440 and 109ppi.

It's hard to believe that apple won't start offering at least a 3840x2400 27" or 30" Cinema display shortly after releasing the iPad 3.  They just announced a new port called Thunderbolt that will replace DVI, Display Port, and FireWire.  This could allow Apple to support even higher resolution displays.  All Apple computers including the lowly $600 mac mini have these Thunderbolt ports capable of driving displays at resolutions well above 1080p.  Apple is very well positioned to finally bring computer displays into the 21st century.

Update: I'm not particularly a fan of Apple other than they tend to be very progressive about pushing technologies and have pretty much been right in the past.  My desktop of choice is Linux which is why I'm so concerned that Apple might have an enormous lead in high ppi monitors.

Monday, July 18, 2011

License Plate Recognition

Based on image by woody1778a
Pennsylvania has 14,000 intersections with traffic lights.  I picked Pennsylvania because is was the first to show up in a Google search. They are as good as any state to use as an example of why eventually the date, time, GPS location and license number of every car using any intersection will be recorded.

Pennsylvania has a budget of almost $4 billion.  14k automated license plate recognition(ALPR) devices would have an initial upfront cost of at most $100 million.  To maintain the system would cost about $15 million if all the system did was log data, alert police about problems tags and allow ad-hoc searches.  I'm basing all this on the cost of systems with many fewer ALPR devices so the cost should be lower given the volume being purchased.  In addition, the other systems do much more such as issue speeding tickets and running red lights among other things.  I'm calling it a wash on yearly costs because of the greatly increased amount of data balanced out by it being much less complex since it would not issue tickets.

One of the more difficult problems with these systems, especially in the US, is they have to quickly account for changes if a state adds more characters to their tag or changes the type of font used.  To track out of state traffic requires that the system keep up to date with a the tag changes from at least the contiguous 48 states.  Also when a tag is scanned there is no way to tell which state the tag belongs to because the numbers are repeated from state to state.  From what I've read, when a tag is flagged as a potential issue, such as stolen, a person must manually verify that the tag is the correct state.

These issues along with potential public outrage are probably the only reasons a state hasn't decided to institute a system like this state wide.  Public outrage has been ignored for a long time in many other areas by politicians so I believe it's the combination of the technical and political hurdles holding everything back.  The time of ALPR will be near when a state institutes a QR code like graphic that is both easier for a computer to read and also contains additional meta data such as state, VIN, car color and make in addition to the tag number.

It's just a matter of time.

Update: A story from the Boston Herald about Massachusetts gong to storing all the plates they scan when driving around.

Saturday, July 16, 2011

Mozilla's BrowserID: Is it a better way to sign in?

Mozilla recently announced a new effort to improve authentication to websites from a browser.  I applaud Mozilla for attempting to solve a problem that is a very real and pressing problem for the average person.  However, I would have preferred if they had taken a different approach.  Here are a few problems I have with BrowserID.

Identity is base on email address.

I don't see a way to user BrowserID unless there is a one-to-one relationship with email address and an account on a web site. While I would highly suggest a site use email as the identity for authentication, sometimes it isn't possible or desired. If you're an existing site with a large base of users, it can be a challenge to completely switch over to email address as the identity. Some sites also need the ability for users to create many aliases which while possible when using email addresses is more than most users can accomplish.
It's complex for the user.
Someone wanting to use BrowserID to authenticate to a site must first complete the initial process of setting up the email account they want to use with the browser and centralized authority.  While not hard it is an extra step that doesn't seem very obvious.

It's complex to implement.
I've read through all the documentation and I'm not 100% sure I know how the complete process works.  Part of my confusion may be the way they've layered the documentation from a simple YouTube video of user experience to source code.  There is no once completely comprehensive document to read yet.  Fairly new existing technologies are used as part of the system and have their own layers of complexity.

I can't implement anything as critical as an authentication system until I know how everything works from beginning to end.  I'm sure this will improve with time but it's complex enough I keep discovering new bits and pieces to how the system truly works as I read more docs/code.  As an example, I didn't know BrowserID used webfinger until I started reading about Verified Email Authentication Protocol, another piece of technology used by BrowserID.