Thursday, December 25, 2008

Comcast Summary

Some of you readers wanted to know what became of the Comcast saga. I thought I had made it clear in the last post of the series, but upon reading it I see that I did not. Here's what my setup is now:

$12.95 for Basic Cable (channels 2-13, essentially)
$1.79 for two CableCards

The CableCards give me the HD channels 902-913 for "free." I don't have to pay the $8.00 fee to receive them.

I'm very happy with this arrangement. I did buy an outdoor HD antenna and briefly tried it out. It received the stations well, but I was worried about the trees that obscured the line-of-sight to the transmitters about 40 miles away. I ended up returning the antenna and sticking with cable.

A friend has encouraged me to try the antenna again and ditch cable entirely. I may do that when I get the time. That will save roughly $15/month.

Monday, October 13, 2008

Printer resolution, demystified

Someone wrote to me with a question about printing getting a digital photo printed in a magazine:

Attached is a photo that blows up very well on screen. However, I keep getting told by journal publishers that they need them with more pixels. Can it really be so that sufficient resolution on screen will not turn out to be sufficient resolution when printed (in the same or even smaller size)?

Attached was a 1700x1200 pixel image.

My reply:

You should give print publishers the largest possible image size so they have the flexibility to reduce or enlarge it as needed.

Let's see if I can explain it.

Every output device, such as a monitor or printer, has a native pixel density, called pixels per inch, or PPI, and also incorrectly referred to as dots per inch (DPI). A monitor is typically somewhere around 75-100 PPI. A printer's PPI will be stated by the manufacturer; for example, 600 ppi or 1200 ppi.

Let's take a 600ppi printer as an example. A resolution of 600ppi means the printer prints 600 pixels per inch in each direction. Each square inch of paper is filled with 600x600 little droplets of ink.

If you take a photo that's 1000x800 pixels and print it at the printer's native resolution, how big will it be?

It will be 1000/600 inches by 800/600 inches, or about 1.7x1.3 inches. Each pixel in the image becomes a tiny droplet of ink on the paper. That size is fine for a postage stamp or a business card, but what if you want to print a 4x6 inch picture?

A 4x6 picture would need 4x600=2400 pixels in one dimension and 6x600=3600 pixels in the other: a 3600x2400 pixel image. In other words, in order to print out a 4x6 image so it appears the sharpest and most detailed on the printer, you need to send it an image that's 3600x2400 pixels.

"But!" you protest. "3600x2400 is 8.6 megapixels. That's more than my digital camera has. You mean my $1500 digital SLR can only print small 4x6 photos? How can I print out anything bigger than about a 4x6 image if my camera's sensor doesn't have that many pixels?"

Well, here's where you can fudge things a bit. The calculations are still fundamentally the same, but things get a little blurry, literally.

The human eye simply can't see anything as detailed as 600ppi. There aren't enough rods and cones in the eye to do it. So although the printer is capable of printing 600 pixels per inch, only about 300-400 of them are actually visible.

Couple that with limitations in print technology itself. You know from personal experience that when you touch ink to paper (say, when you a black marker), the ink spreads a little. It's no different in an inkjet printer. The printer may be spitting out 600 little droplets of ink for every inch, but they smear together such that the effective resolution of the printer is around 250-450 ppi, depending on the paper and ink being used.

Let's settle on 300ppi as a nice average of both eye resolution and printer resolution and rework the previous example.

A 4x6 print at 300dpi is 1200x1800 pixels. In other words, you can print out a 1200x1800 pixel image at 300ppi and it will look pretty much the same as the 600ppi image. But you can't get away from the native resolution of the printer. The printer can't actually print anything at 300ppi. So here's what actually happens:
  1. You direct the computer to print the 1200x1800 image, scaled to fit 4x6 inches. The computer calculates that to be 300 ppi.

  2. The printer driver takes the 1200x1800 image and scales it up to 2400x3600 by doubling each pixel in both directions. The image is now scaled to the printer's native resolution.

  3. The printer prints the 2400x3600 image. It occupies 4x6 inches of paper. It comes out looking pretty good.
Let's say now you take that same 1200x1800 image and direct the computer to make an 8x12 inch print out of it. What will happen?
  1. The computer calculates the resolution to be 150ppi.

  2. The printer driver scales up the image to the printer's native resolution of 600dpi by quadrupling each pixel in each direction. The image is now 4800x7200 pixels.

  3. The printer prints the 4800x7200 pixel image onto an 8x12 inch print.
But what does the print look like? Is it sharper, blurrier, or the same as the 4x6 print? A: at only 150ppi, it's blurrier than the 4x6 print because the same 1200x1800 pixels now effectively occupy a larger area. Each pixel had to be printed bigger to fill the area, so it appears less sharp.

Do you see what's happening here? An 800x600 pixel image looks great on your monitor displayed as a roughly 8x6 inch image on the screen, whose native resolution is around 100ppi. The image is as sharp as it's going to be on the monitor, so you think "Wow! I'm going to print this out!" Although it would look great printed as a 2.6x2 inch print (300ppi), it would look lousy printed as a 4x6 print (133ppi) and really crappy as an 8x12 (66ppi).

So back to your magazine publisher. Let's say they want to print your flower picture as a 4x6 in the magazine. Let's also assume they have a really high quality printer with good, glossy paper whose effective resolution is 400ppi. How many pixels should your image be to make the publisher happy?

4x400=1600, 6x400=2400. Your image should be at least 1600x2400 pixels. More pixels would give the publisher some flexibility, since it would allow them to print the photo larger without having to reduce the pixel density. Scale your image to at least 1600x2400 pixels. Don't worry about PPI or DPI; just give the magazine an image at least 1600x2400 pixels.

Here are some common rule-of-thumb output resolutions:

75-100 ppi: screen
200: fax machine
300: ca. 1990 B&W laser printer
300: effective resolution of a consumer inket printer
350-400: limit of human eye
400: Costco 1-hour photo
400-450: high-quality offset color printing press
600: modern B&W laser printer

Hope that helps!

Thursday, September 25, 2008

The Bailout: So Many Questions, So Few Answers

I can't help but feel that this $700 billion bailout is Washington's last attempt to issue free money to Bush's Big Banking Buddies at the expense of taxpayers. Although the headlines read that lawmakers have reached an agreement today on the terms of the bailout, so few details have been released that I am left with so many questions.

Which institutions will be allowed to benefit? The news is full of big names like Lehman Brothers, AIG, and Washington Mutual. But what about the smaller regional institutions, like Umpqua Bank, Bank of Montecito, and River City Bank, who specialize in providing banking and lending services to Small Town USA? Surely some of them are in financial trouble, being saddled with bad debt stemming from the housing boom. I haven't heard anyone speak up for them. Will they be allowed to go under while larger banks snap them up using bailout funds?

What about institutions with other kinds of debt, such as credit card debt? Will Citibank be allowed to write off billions of dollars in consumer debt and essentially start over with a zeroed balance book? Who decides what kinds of debt are covered under the bailout bill and which are not?

This bailout does nothing to fix the underlying problem.

President Bush went on the record last night to explain to the taxpayers how we got into this mess. The problem, as he stated, stems largely from the poorly-managed mortgages wrapped up into complex securities that buried the risk. This bailout is necessary, he said, to buy up the bad debt and allow banks to resume lending.

That's great, but it's like applying a Band-Aid to a patient with internal bleeding. The financial vehicles for this disaster still exist:

  • It's still possible to create complex securities out of bad debt and sell it to unknowing investors.

  • It's still possible to sell a house to someone who can't afford it.

  • We'll still have greedy mortgage brokers pulling the wool over lenders' eyes. The broker gets paid when the mortgage is signed, and keeps the money even if the homeowner defaults.

  • And we still have many homeowners teetering on the edge of delinquency whose defaults have yet to show up on banks' balance sheets.

Secretaries Paulson and Bernanke say the time to do the bailout is now; changing the regulatory laws will be done later, once the financial system has been stabilized. When is "later?"

"Later" is after the new year. We'll have a new President and a new Congress. Many of them will be new to Washington, new to the intense lobbying that comes with the job. You can bet that the Big Banking PACs, flush with $700 billion in cash, will really turn up the heat on our representatives to convince them that the regulatory laws which so desperately need changing should either be left alone or altered to benefit the banking industry.

Imagine the kind of influienc you could have on your representative if you had even one million dollars. Now imagine what you could do with $700 billion.

I'm not convinced that, once the dust settles, that anything will have changed at all. But I do know this: the Big Banks will be $700 billion richer and we taxpayers will be $700 billion poorer.

Friday, September 19, 2008

"The Cloud" Saves the Day

So my iMac went in for repairs. The video card needs to be replaced. I suspect that it's been bad for quite a while, but since I don't play games, it hasn't been an issue. Until I started seeing more and more blocky artifacts scattered about the screen.

The computer will be gone for 3-7 days. Am I completely dead in the water until I get it back? Of course not, and here's why.

First, I have a backup computer: my trusty MacBook Pro which I carry around just about everywhere.

But what about my data? Thanks to "The Cloud," I have nearly all of the necessities easily accessible.

My email--four accounts' worth--is stored on IMAP servers, meaning the messages themselves are kept on the mail server and downloaded to my computer only when I need to read them. They stay on the server until I delete them. And even then, GMail archives them for a couple of years instead of deleting them outright. All of my email is equally accessible from any internet-enabled device: my MacBook Pro, iMac, iPhone, and anything with a web browser. GMail for domains is my hero.

My address book, email account settings, calendars, and Safari bookmarks are all synced among my three Apple devices using MobileMe, a service that costs about $99 per year. Well worth the money just for that feature alone.

Many of my bookmarks are also stored on, a social bookmarking site. Thanks to a plug-in for Firefox, the bookmarks are listed right in the Bookmarks/Favorites menu; I don't have to go to the website just to see them.

I have lots of notes, to-do lists, and web clippings stored in Evernote, a free service that stores the notes in the cloud and syncs them to all my devices almost in realtime. If you've never tried Evernote, do so. The coolest thing: picture notes. I just snap a picture with my iPhone or the camera built into my computer and it's instantly uploaded to Evernote. There, some magic happens: all the text that's visible in the picture is recognized and made searchable. For example, I recently needed to go to the pool supply store to have my spa water tested. The guy there recommended some chemicals I needed to buy to balance the water. Before I left, I had taken a picture of all the chemicals I already had. I simply typed in the name of the chemical and if the picture popped up, I knew I already had it and didn't need to buy more. Nifty!

All the important data and applications on the iMac itself are backed up through a an online service called Mozy. It's free for backups of up to 2GB; about $5/month for unlimited backups. If my Time Machine backup ever fails, everything I need to get a new machine back in service can be downloaded from the Mozy backup.

There you have it. Cloud Computing is the future, thanks to the Internet. But the next time I write about The Cloud, it will be when the Internet has blown up and none of my data is accessible.

Wednesday, September 17, 2008

Comcast, Back In My Life?

Today's Status Updates
I think Comcast and I have reached an amicable agreement, thanks to good folks like Frank Eliason. About an hour ago I got off the phone with Mary, a regional rep from San Mateo, and we arranged for a very inexpensive HD package consisting of:

Basic Limited Cable, $12.35
Two CableCards, $1.79
Monthly total: $14.14 plus taxes and fees (approx. $19 total).

That's good news, and cheaper than I expected! This package will give me the local broadcast stations, public access channels, and QVC and/or HSN.

However, I also just got a return call from Herman James who expressed doubt that the package would actually work in Sacramento, citing some possible "technical issues." We'll see how this pans out.

In the meantime, UPS delivered my antenna today. Out of curiosity, I'm going to hook it up and see how well it performs.

Finally, I inquired with Discovery Channel about the availability of MythBusters on legal download sites, such as and iTunes. They wrote back:

Dear Viewer:

Thank you for taking the time to contact Discovery Networks. We appreciate
your interest in our programming and are delighted to hear from our
viewers. Unfortunately, Mythbusters is currently not available for

We apologize for any inconvenience this may cause.

Boo. Will I need to wait until after the season is over to rent it? Or will I resort to BitTorrent?

A bigger question is: would I rather pay $19 for basic cable, or get the same service from an antenna for free? I think so. Setting up the antenna will cost about $200. That will pay for about a year of cable service. Over the long run, cable will cost more, for sure. But it might be worth not having to hassle with the antenna.

Still, I'm going to hook it up and see for myself. :)

Monday, September 15, 2008

No Love From Comcast

Called Herman today and left a message. He hasn't returned the call. So.... I ordered the antenna and mast from They should be here by Thursday, just in time for my cable to be turned off.

What I'm Asking For

Let's be clear about a couple of things: I'm not asking for Comcast to lower their rates. I'm not asking for them to make any undue sacrifices. They are free to charge whatever rates their customers will pay.

What I am asking for is the absolute cheapest HDTV package. After looking through their website at all of the packages available, I believe that the following combination is possible:

Limited Basic Cable. Covers channels 2-13 plus a few others like public access, and the Home Shopping Network (ugh). $12.85.
Limited Basic HDTV. An $8.00 add-on for any cable package. It gives me the HD versions of the channels in the other package, where appropriate.

Combined, this package should cost roughly $20.85, plus taxes and fees. But the customer service rep I spoke to last week insisted that I also needed to rent a converter box. She claimed that because the package I was trying to order "was not a digital package," a converter was needed to receive the HD channels.

Say what? What, exactly, is that converter box converting?

Perhaps she thought I had an "HD Capable" TV, which does need a tuner in order to receive HD channels. But not only is my TV "HD Ready," so is my TiVo Series 3. The latter even has CableCard slots, conveniently filled with two Comcast CableCards that I've been using the past two years.

Or perhaps the converter is needed to convert the analog channels into digital versions that my TV/TiVo can receive. That doesn't hold water. HD channels are by definition digital. I'm only interested in receiving the local broadcast stations in HD: KCRA, KXTV, KOVR, etc. Believe me, being able to watch HSN in stunning digital is the last thing on my list. It ranks even lower than the public access channels. I've got my TiVo configured to never, ever, EVER record that channel.

So there you have it. My request to Comcast is humble: bundle Basic Limited Cable with Basic Limited HDTV for roughly $20. Your website says it's possible. Will you do it? If not, I'm getting the antenna.

Sunday, September 14, 2008

Comcast Continues to Respond

If you've been reading the comments on my original blog posting about Comcast, you've seen that they've responded. Apparently they have employees who scan the net and look for disgruntled customers. Kudos to them, I say. Note that I'm not disgruntled with Comcast -- I just don't feel like paying $75/mo anymore.

I also received a voicemail on my home phone. (I included my phone number in the email I sent directly to their customer service dept.) It was from a Herman James, representing the Sacramento region. Unfortunately, I didn't listen to it until after business hours, so I'll be calling them back on Monday.

In addition, I posted an ad on Craigslist inquiring about TV antenna installers. I got two responses that I'll be following up on.

The ex-Comcast saga continues!

Friday, September 12, 2008

Comcast's First Response

This morning, a semi-automated response was waiting in my inbox. Clearly, they missed the point.

Dear Mr. Brown,

Thank you for taking the time to write to the Comcast Office of Rick Germano, Senior Vice President of Customer Operations. My name is Robert and I thank you for this opportunity to assist you regarding your Billing inquiry. We apologize for the delayed response.

We need to hear about any unsatisfactory situations in order to correct them and to enhance our level of customer service. I have forwarded your comments to the appropriate members of our development and management teams for further review Mr. Brown. I do hope the following information is useful to you.

What is the digital television transition?

Keep in mind that only older "analog" televisions relying on Broadcast signals (through the air) will be the equipment that is truly affected by this change.

Information for the Digital Broadcast Transition

At midnight February 17, 2009, Congress requires that all TV broadcast stations (such as ABC, CBS, NBC, Fox, PBS and Univision) begin broadcasting exclusively in digital format. This switchover is referred to as the broadcast digital TV (DTV) transition.

Consumers with analog TVs that rely on antenna reception such as rooftop antenna or rabbit ears to get your TV signals (not connected to a pay TV service like cable or satellite) will need to take action to ensure continued reception of broadcast channels on these TVs. Their options include:

1. Request a DTV Converter Box Coupon
2. Purchase a new TV capable of displaying a digital signal (still requires adequate antenna reception)
3. Subscribe to pay TV service like cable or satellite

What is the TV Converter Box Coupon Program?

Congress created the TV Converter Box Coupon Program for households wishing to keep using their analog TV sets after February 17, 2009. This program allows U.S. households to obtain up to two coupons, each worth $40 that can be applied toward the cost of eligible converter boxes.

The TV Converter Box Coupon Program can be contacted 24-hours at Coupon Program Hotline at 1-888-388-2009 or visit the website mentioned. Hearing impaired customers can call the TTY number which is 1-877-530-2634. Please note the TV Converter Box Coupon Program is Government run program and not affiliated with Comcast. For more detailed information, please visit this website

A TV connected to Comcast service does not require a TV converter box from this program (this includes Comcast customers with Limited or Full Standard Service only). NOTE: Comcast has agreed to continue to carry broadcast network signals in analog format for a minimum of three years following the Feb. 2009 conversion deadline. This means that Comcast customers will still not need a converter box to still receive these signals. To be clear, all they need to have is their TV connected to the Comcast cable network.

Additional information available and useful Links.

What you should know about February 17, 2009 for the cessation of Analog broadcasts and Digital conversion:

FCC Homepage:

The FCC's special website, has more information on digital television, or you can call 1-888-225-5322 (TTY: 1-888-835-5322).

Comcast is committed to provide the best customer experience possible. We look forward to your continued feedback Mr. Brown and we hope to be able to continue to provide you with our services. Please contact us if you have any questions or require additional information.

Thank you for choosing Comcast.


Office of Rick Germano

Thursday, September 11, 2008

Dear Comcast

Dear Comcast,

After six years as a customer, I have decided to end our relationship. I have found myself watching less and less TV. Consequently, I felt that the $75 per month I sent you was simply not giving me enough of a benefit. The numbers don't add up anymore. Let me explain.

What does $75 get me? Local broadcast channels (ABC, NBC, CBS, etc.), over one hundred cable channels in your "Digital Preferred" package, and HDTV versions of those channels where appropriate. Of those roughly two hundred channels, I regularly watch only about ten of them. Even among those ten, I added up that I watch approximately fifteen hours of TV per month. That's about a half-hour per day, on average. I'm paying five dollars per hour.

The shows on those ten or so channels overwhelmingly consist of broadcast HDTV shows on NBC, ABC, Fox, and CBS. I'd say 80% of my viewing is broadcast TV. The rest are a smattering of cable-only shows on networks such as Discovery, TLC, and HGTV. I don't watch sports. I don't watch pay-per-view. I don't even watch movies on Starz; I'd rather rent a DVD for that.

I'm sure you're well aware that the broadcast networks can be received over-the-air in HD via an inexpensive antenna. Therein lies the rub: I'm paying five dollars an hour to watch TV I can receive for free. The rest of my TV diet is easily accommodated by inexpensive services such as Amazon Video on Demand (built into my TiVo) and iTunes (displayed on my TV by Apple TV). Even broadcast shows are easily viewable on the TV from the networks' respective websites. Local news -- with video -- is available online, too.

You see, I'm going to get almost all of my TV viewing from the airwaves for free or from online sources for free or very inexpensively. And I'll save money -- an estimated $500 or more per year, even including the upfront cost of buying an antenna and Apple TV. It's all legal. No BitTorrent, no Limewire. I believe in rewarding the studios, actors, and productions crews for shows that I enjoy.

I tried to talk your kind customer service representative into offering me Basic Limited cable ($12) plus Basic Limited HDTV ($8), but she countered with a $40+ package that included a hundred or so channels that I will never watch. Twenty dollars I would have happily paid, but $40 was too much. I'm sorry it didn't work out.

I'll give you another chance, Comcast, if you will accept my offer: Limited Basic HDTV for about $20. And please don't upsell me on a converter box. I don't need one. My TiVo and TV are perfectly capable of receiving digital HD signals, as the last six years certainly testify. Will you do it?


Barry Brown

Saturday, July 12, 2008

My close call with greatness

I was thiiiiiis close to greatness last night. The workshop had ended and a bunch of us were getting ready to go to Chinatown to get dinner. Goeff Knauth (instructor at Lycoming College in PA and one of the attendees) asks, "shall I call Richard Stallman and invite him to dinner?"

Can someone really turn down an invitation like that?

A phone call was made; message left; and shortly returned. Richard would love to join us, but is currently in France and can't make it in time.

Bummer. But how cool would that have been?

Sunday, June 15, 2008

I'm a stickler for quality. And a cheapskate at heart. Conflict arises, especially when I'm getting into a new hobby or activity.

A couple of cases in point:

About a year ago I wanted to buy one of these new digital oscilloscopes. They have LCD displays, can capture signals, and do real-time analyses on the inputs. Neat stuff, and much better than their analog predecessors.

Like most things, they come in a variety of price points. The cheaper units has B&W LCD displays and narrower bandwidth. Being my first digital o-scope, I bought a used one off eBay for about $200. After playing with it for a few hours, I wanted more. More bandwidth, faster display, color.

My next purchase was a new, Chinese-made color LCD unit for about $1,000. It had great reviews online and, indeed, it's a nice unit. But although it had a huge memory for capturing digital signals, the display was kind of "noisy" and it didn't quite have the bandwidth I lusted after.

Finally, I purchased the unit I should have bought in the first place: a Tektronix TS3012 color LCD digital storage oscilloscope for about $1,200. It's fast, built like a tank, and still supported by Tektronix even though it's used (another eBay purchase).

In other words, I spent on my dream 'scope the same amount of money I spent on the first two 'scopes that are now sitting on a shelf. I spent double, needlessly.

Another case in point: as a teacher, I'm getting more into online instruction. And I might dabble in podcasting. So I bought the typical starter kit:

Basic condenser microphone (Audio-Technica 2020), $100.
Basic mixer (Behringer 802), $60.
iMic USB interface, $50.

But I quickly ran into limitations. Being a condenser mic, the AT2020 picked up way too much room noise for my taste. So I upgraded to the Electro-Voice ND767A super-cardioid dynamic, $130.

The wimpy Behringer mixer was quickly replaced with a Yamaha MW10C, $200.

Boy, that Heil PR-20 microphone sure is looking nice. Heil, known among podcasters for its PR-40 studio microphone, makes great microphones right here in the USA. Well, better order one of those. ($150)

Then I start really getting into different ways that might students might be "calling" into class: either through CCCConfer or through Skype. I need a way to cross-mix the two inputs. And I'd love to have Firewire so I can send all the audio inputs to the computer separately, rather than mixing them down to a single stereo track. That Yamaha mixer just isn't going to cut it.

So, off to eBay to get a Mackie Onyx 1220 Firewire mixer, $800.

After using it for a few hours, I still can't quite get the inputs to mix correctly. Next purchase, Behringer UB1622FX mixer along with a Behringer UCA202 USB interface (to be used in conjunction with the iMic). Total for this purchase: $170.

But wait! I think I might be able to get the Mackie to do what I want! Too late, the Behringer is on its way.

Finally, here we are on Sunday evening. I'm lusting after that Heil PR-40 again -- the microphone I should have bought in the first place.


Wednesday, March 12, 2008

Finding the median value in SQL

Most SQL dialects don't come with a median function. But one can be cobbled together using the procedural programming language that accompanies most databases.

They work like this:
1. Sort the list of values.
2. Count the number of items in the list.
3. Select the element at position n/2.

A function like this can't be expressed purely in SQL because SQL is not procedural.

I've come up with a median function that uses pure SQL:

select age
from person
where (select count(age) from person p1 where p1.age >= person.age) -
(select count(age) from person p2 where p2.age <= person.age) between 0 and 1;

This technique uses two correlated subqueries. The outer query works through the list of values (in this case, age). As it considers each age in turn, it counts the number of ages that are greater than the target age and the number of ages that are less. The difference between the two should be 0 or 1 (depending on whether there are an odd or even number of ages to consider).

When the difference is 0 or 1, you've found the median value.

This solution is O(n2). Expect it to take a long time on large data sets.

Sunday, March 9, 2008

I'm so excited, and I just can't hide it!

As you know from one of my previous posts, I have a list of things I'd like to do during my lifetime. My upcoming sabbatical is going to give me some elbow room to get a few of the items checked off!

During my spring break, I'm going to make a hologram. I've already got all the raw materials: laser, holographic plates, chemicals. After a quick trip to Home Depot, I'll have the pieces needed to build the table on which holograms are made.

Right after school lets out, in May, I'm heading to Florida to watch the next Space Shuttle liftoff. I've built into my schedule a few extra days in case it doesn't blast off on time. As long as liftoff is within three days of the scheduled date, I'll be OK.

2008 is going to be a great year!