Monthly Archives: October 2007

Getting to Know All about You, pt. 3 – Software Quality Assurance

Last year I took a software testing course. A handful of software testing and quality blogs still hang out in my feed reader. In addition to the ones I wrote about last year, you might find these interesting.

Posted in General, Software Engineering, Worthy Feeds | 2 Comments

Getting to Know All about You, pt. 2 – Moribund Adobe Blogs

Adobe is really big — trust me, I visited them once; they have a whole tower for PostScript and its children — so you’d think they have some good blog writers. And you’re right.

But today let’s remember some of their better public blogs that have one foot in the grave or are no more:

Posted in General, Worthy Feeds | Leave a comment

Getting to Know All about You, pt. 1 – The Beeb

I have way too many RSS feeds. Most go unread, which means I might as well just remove them and let the people who are less lazy than me that I trust summarize the web for me. But some I rather like and would surely miss, even if the information is months old by the time I get to reading the feeds.

But I believe I should simplify, simplify.

My plan is to visit each of the 100-or-so feeds in my reader, read some articles from the feed, and then either post it here for you, my dear friends, or just set it free.

First up, three feeds from the BBC:

Posted in General, Worthy Feeds | Leave a comment

Four days in London

I love international travel. Don’t get me wrong; visiting different parts of the U.S. is great, too. I’ve just always had such a great time being foreign.

To be honest, I can’t really believe that almost three weeks have passed since we went to London. Work and classes have kept me busy since our return, delaying me from posting pictures and an itinerary for those crazy enough to try to visit London over a long-long weekend. Despite rumors to the contrary, such a trip doesn’t present too many challenges. You won’t see everything, but definitely enough to make you eager to come back for more.

Caveat #1: I’m a big fan of red-eye flights when going in an eastward direction. If you’re not, you’ll need to pad your trip appropriately. In addition, we only lost five hours via time zone changes overnight. Once again, your situation may require more jet lag adjustments.

Caveat #2: We’re not exactly party animals. If you imbibe, you may need to plan on doing somewhat less than us.

Caveat #3: After almost a decade of really poor fiscal policy from so-called conservative government, an atrocious national current accounts balance, and falling confidence in a once rock-solid American currency, the dollar was trading at $2.27 per British pound as our trip began. When coupled with the fact that the prices listed on goods are roughly the same in both countries despite the unfavorable exchange rate, we didn’t do a lot of shopping. (£11 for the new Bruce Springsteen CD? I think I’ll wait ’til we get home.) If you have a large budget, feel free to go nuts.

On to the itinerary. . .

Day One — Getting Oriented

Arrive at London’s Heathrow Airport sometime around 7:30 and go to the immigration line. This is your introduction to queuing. You’re in Britain. You’re going to queue. Also notice how multicultural London is. We were between some obnoxious older women from Boston and some Arabs women in full abayas and niqabs. At the airport we got a bite to eat, a SIM card for our mobile phone (an unlocked, multiband model we bought before our trip to India), and tickets for the Underground. We definitely recommend getting “Oyster cards”, the smart card that gives you reduced fare prices and extra convenience.

After dropping of your luggage at the hotel several hours before you can check in, why not take a walk around to see what London is like. Be sure to read the instructions to “Look Right” and “Look Left” when crossing the street. As far as we could tell, they’re not just for tourists, since sometimes it’s hard to tell which direction the traffic will be coming from.

Our first stop was the Victoria and Albert Museum, a truly random assortment of high-end stuff. The fashion collection is really quite exciting.

The V&A is a great introduction to the London of Queen Victoria and her beloved Prince Albert. Their name is on everything around London. Of course, she did reign for more than sixty years, she was crazy in love with Albert and wanted to show it, and England was reaching the zenith of its imperial power. There was a lot of money for the powerful, and the nation was really proud of its position in the world. In nearby Kensington Gardens, there’s an enormous monument to Albert, with statuary depicting the four major continents of the British Empire — Europe, Asia, Africa, and America — making up the pedestals upon which monarchical power rested.

We enjoyed a pleasant stroll through the gardens and adjacent Hyde Park. We saw lots of people enjoying the beautiful early October weather as we walked past Kensington Palace. Speakers’ Corner appeared to be all talked out by four in the afternoon, and the Marble Arch was a bit out of the way. But in its shadow, we saw a washed up skinhead (complete with Dr. Marten boots) who looked like he might have been an extra in “This is England“. (The first five minutes of the Shane Meadows film is perhaps the most brilliant film introduction I’ve ever seen.)

The jetlag combined with the scant sleep from the red-eye left us in a perpetual limbo, not knowing (or really caring) what time it was throughout the whole trip. But on the first evening, we felt it a bit more, so we headed back, checked in, and got a bite to eat in Earl’s Court. The food in England gets an undeservedly bad rap. In London, at least, we had a lot of really good food — Thai, Indian, gourmet burgers, gourmet pizza, etc.

The night life in London is pretty vibrant, too. On our next trip we definitely plan on seeing a show in Covent Garden or going to the pub with friends, but this trip we took it pretty easy in the evening, attempting to divine the rules of rugby, working on homework, and doing other rather boring activities.

Day Two — Museum Hopping

We came to London with very few plans. We knew there was more to do there than we would have time to accomplish, so we just decided to hit a few things near the top of our list and then whatever else happened to be nearby. Lisa loves paintings by the Pre-Raphaelite Brotherhood, so we visited the Tate Britain, which just happened to have an exhibit on Millais, allegedly the best of breed.

Two things topped my list: the British Museum and London’s modernist architecture. The latter was on display everywhere, so we took the tube over to the museum, saw the world’s largest enclosed public square, marveled at the Rosetta Stone and loads of other cultural treasures, which somehow includes both Napoleon’s and Oliver Cromwell’s death masks.

Leaving there we walked through trendy Covent Garden on our way to the National Gallery and Trafalgar Square. We planned to visit the Photographers’ Gallery on the way, but couldn’t find the exact street we needed. While we stood looking at our rather good map trying to figure out where we were, a trendy fellow about our age asked if we needed if needed help. That sort of thing would never happen in Boston or NYC.

Trafalgar Square was full of people. It was glorious.

Day Three — The Death March

Our third day was supposed to start with a “flight” on the British Airways London Eye (Get it? British Airways? Flight? Ha!) followed by a bit of walk around Central London ending with a bus ride to Cambridge to see friends from the UK office of The MathWorks. But conflicting information on the Hinterweb led me to believe that we needed to book tickets, which caused me more than an hour of frustration ending with the Internet dying and us deciding that Cambridge would just have to wait for our next trip to the fair island.

So Sunday began at our typically early hour of 9:00 or so with a trip to the pastry shop and a ride on the Underground to Waterloo Station. I could hear our British friend Tish’s words in my mind as we walked through the terminal on our way out of the station: “You could go to Paris in two hours on the Eurostar if you wanted to.” Next time.

The nearby London eye, an enormous glass-enclosed observation wheel rising over 400 feet above the Thames, is well worth the somewhat high ticket price. The views of Parliament, the City, Buckingham Palace, Saint Paul’s Cathedral, and the Thames were pretty good despite the haze. It was nice to have an idea of where we were going on the day’s death march.

First, across Westminster Bridge to see Big Ben and Parliament. Britain hasn’t yet succumbed to paranoia about every last little thing, and you can still walk right up to the building (or at least to the ornate gates around it). Then to nearby Westminster Abbey. Church was going on, and we could hear the great organ playing, but heathens like us were satisfied seeing the 13th century chapter house and its frescoes and stained glass windows, some of which survived World War II.

Then we had lunch with Her Majesty the Queen. That is to say, we had lunch and then saw Buckingham Palace. (We didn’t actualy see E.R. in the hizzle.) Again we thought of empire while looking at the Canada Gate and South Africa Gate and every last gilded thing. The Queen Victoria statue seemed to have lost her nose at some point and received a new one (just like Tycho Brahe except hers was marble not gold alloy).

We strolled along the mall and through the arch in the Admiralty Buildings just in time to see the changing of the horse guards before seeing Lord Nelson again at Trafalgar Square. Across the Hungerford footbridge we started walking downstream along the Thames Embankment, a pleasant wide pedestrian thoroughfare with trendy shops, cafes, and used book sellers.

We popped in the embarrassing Tate Modern. I’m usually a fanboy for modern art, but even I had to alternate between choking down my bile and just shrugging my shoulders. Poor Lisa, the Calder mobile was too small to make up for the indignity she suffered finding it.

Across the no-longer-wobbly Millennium footbridge, into the historic City of London, past the heraldic registry of coats of arms, and up the hill to Saint Paul’s Cathedral. It’s quite an imposing edifice, enormous inside and quite beautiful. Because it was Sunday, a day for quiet reflection and prayer, we couldn’t see most of the church. Finally, down Cheapside and Poultry Streets to the Bank of England, which was wrapped like a Jean Claude and Christo installation.

Day Four — Windsor Castle

What can I say about Windsor Castle? Well, it’s a nice day trip, that’s for sure. On weekdays, trains go there directly every half-hour or so. The twenty-five mile trip takes about an hour and passes through some of the less savory parts of London before entering what passes for suburbia in England near Heathrow and then some tony semi-rural burgs.

The castle itself is quite impressive. In fact, it wouldn’t be a terrible place to live, but I would definitely need to change a few things inside the state apartments. The room with the decorations made out of weapons can stay, but most of the rooms were just so gaudy and overwrought. The simplicity of the Garter Throne Room moved me unexpectedly, but as someone committed to the principles of republican democracy I just couldn’t get over the idea of one family having a divine right to all of that wealth and power. I know they’re just people destined to live lives of luxury, boredom, and public scrutiny simply by accident of birth, but it seems anachronistic.

Windsor town is the closest thing to a tourist trap that we saw in England. It must be absolutely mad during a summer weekend, but on a Monday in early October there weren’t many people about. In fact, early October is a great time to visit London.

What I’m going to write next might seem contradictory given what I what I’ve said about opulence and tourist traps, but I really enjoyed Harrods Department Store. We stopped in the world’s most famous department store on the way back from Windsor. The guard at the door said something almost indecipherable — “Carryabaginyand.” — the first time during the trip that we really felt like we’re from two nations separated by a common language. I faked being foreign: German or Canadian or something. “Your bag. Carry it in your hand.”

After a few galleries (for want of a better term) I could see why I needed to exercise extra caution. Lisa fancied the £480 handmade glass frog. I rather fancied the mammoth tusk for a mere £9,600. We both thought the Persian carpet for £16,000 seemed a bit excessive, though. We ended up just buying some chocolates; after all, we could buy $700 Jimmy Choo shoes back home . . . not that we would, of course.


It started to rain lightly as we left Earl’s Court for Heathrow, just in time for us to return home.

Four days hardly seemed enough time to see this fantastic city, but it was all we could do with the time and money that we had. Next time we’ll go to Cambridge (and maybe Stonehenge), see a show, watch rugby at the pub, and stalk M.I.A. in East London, where the Desis live. London is not just one of the world’s great cities but a city that seems to have the whole world; it seems right to visit some of the London neighborhoods and see more of the globe. (I’m sure it will be just like Epcot. Ha!)

Posted in Europe, Travel | 3 Comments

London v. NYC

One of my very good friends, who is also a coworker, loves New York City and started ribbing me for saying that “London may be the greatest city in the world”. This despite the fact I was sharing frou-frou chocolates from Harrods and plain old Cadbury’s milk chocolate from Sainsbury’s. (After tasting the Cadbury’s chocolates, I must agree that it tastes better than its American cousin and Hersheys, too.)

I ♥ NY, too — and it’s a lot closer to Boston than London — but I’m going to stick to my story here. To be fair, let’s admit that New York has the edge when it comes to tall buildings and shopping and nightlife and quirky neighborhoods. There are more museums and galleries than you can hope to visit in a month. It’s the capital of fashion and contemporary art and publishing and consumer culture. Central Park is perfect, especially when you want to escape all the great things about the city. The trains go express. Yankee Stadium is almost as much fun as Fenway. Everybody in the world lives there, the food is great, and the world’s best photography store is on 9th Avenue between 33rd and 34th. And there’s no attitude in the world quite like the ones you’ll find in the five boroughs and Jersey. New York is the best city built on a grid in the world.

But London . . . I could live in London. It adds beauty to function, gentility to urbanity, livability to opportunity. New York encompasses and influences the whole world; London integrates it. On our first train ride we heard people talking in English, Hindi, Nigerian, Russian, Chinese, Polish, German, Dutch, and others I’m probably forgetting. London has fantastic style in type, design, and dress. New York has parks; London has parks with palaces. London is quieter, cleaner. And let’s face it: Londoners are nice.

Perhaps it comes down to this: New York is built on its own money and energy, while London became great largely through empire and capitalizing on other people’s goods, land, and labor. The American part of me salutes and revels in New York despite its coarseness. The human part of me loves London despite its past.

Posted in Europe, This is who we are, Travel | 4 Comments

Hail Britannia

Did you know that residents of the UK need to license any television or device that can play or record television?

And it’s expensive, too. About $275 . . . each . . . a year.

We’re having a great time in London. We’ve seen a lot and been all over. I think this might be the best city in the world, although Vauxhall looked a bit dodgy from the train. Too bad we have to go home tomorrow.

Did we miss anything?

Posted in Europe, Travel | 2 Comments

Film-like tone mapping

Every once and a while someone will ask me why I still use film. First of all, I have a film camera, and to buy a new one would be a significant chunk of cash. But that’s not the main reason. I like the look of film; I know how the various emulsions work and know what I need to do to get the best image from them; and (above all) I like the fact that I have an artifact when I get my film back from the lab.

Digital does have a lot of advantages, though. It provides instant feedback at the point of making the photograph. It’s also hard to beat the speed and flexibility of a digital workflow. And for 35mm-sized sensors, it’s hard to tell the difference from film.

This article mixes the look of film and the enormous possibilities of digital. It also continues the trend of notes about high dynamic range images that I’ve been posting recently.

Color film is an analog tone reproduction operator. It renders a vast range of illumination values to a particular color image. That is, it maps the high dynamic range world to a lower dynamic range representation. The major factors that influence this tone mapping “function” include the exposure settings (shutter time, aperture, and ISO speed), the film response curves, and development technique. A film response curve for Fuji Velvia, the color film I use, appears below. Notice how the curve is more-or-less flat in the highlights and shadows and that it has an S-shaped curve in between.

Velvia film response curve

If you take some liberties with that S-shaped part of response curve where the real detail in the image is, you might almost say that the curve has a flat part for the shadows, a flat part for the highlights, and a line that connects the two.

When I first started puttering around with high dynamic range images, I began by translating what I knew about how film renders a scene with a lot of tones:

  • Film is sensitive across a particular exposure range.
  • Parts of the image with less than a certain amount of exposure are rendered as black.
  • Overexposed parts of image are rendered as white (technically clear).
  • You can’t change the film sensitivity (except with some processing tricks that we’ll ignore).
  • You can change the amount of light that is recorded during the exposure.

It wasn’t hard for me to combine this information with the generalization about the film response “curve” to produce a very simple tone-renderer which simulates color slide film in MATLAB. You can download the M-file from my page on MATLAB Central, where you can find some other good stuff. (I’ve also reprinted it below.) I ran it on the HDR image of my office, varying the exposure from 0 EV to 12 EV in half-stop increments, and was very glad to see the same kind of results that I do with film.

My office rendered from HDR to LDR in 25 steps
(Click for larger image…)

But film is so twentieth-century. :-) So I went on to more interesting forms of tone mapping.

function rgbSimulated = simulateFilm(rgbRadiance, nStops) %simulateFilm   Perform film-like tone mapping. %   LDR = simulateFilm(HDR, middleEV) converts the floating-point high %   dynamic range image HDR to a UINT8 low dynamic range image LDR using a %   method that recreates the sensitivity of film.  The middleEV value sets %   the middle exposure value (EV) for the rendering.  Larger EV numbers %   will generate brighter images; smaller values of middleEV will result %   in darker images. % %   The film sensitivity is set to 6 EV, which is comparable to many %   late-model transparency (positive) films. % %   Example %   ------- % %   Render the same HDR image using different "exposure settings." %   Essentially, simulate exposing the same scene from 0 to 12 EV in 1/2 %   stop steps. % %      % Read the HDR image and create a buffer for the rendered images. %      hdr = hdrread('office.hdr'); %      s = size(hdr); %      ldr = ones(s(1), s(2), 3, 25, 'uint8'); % %      % Perform the tone mapping. %      for p = 0.5:0.5:12.5 %          ldr(:,:,:,p*2) = simulateFilm(hdr, p); %      end %      figure; montage(ldr) % Author: Jeff Mather % Copyright 2006-2007 The MathWorks, Inc. % Set the film sensitivity and the mid-tone log-radiance. sensitivity = 6; midPoint = 3; minLogExposure = midPoint - sensitivity/2; maxLogExposure = midPoint + sensitivity/2; % Film works in stops.  Convert radiance to base 2 to compute perception. % Values that are outside the film sensitivity are lost (min or max). rgbRadiance = rgbRadiance * 2^(nStops); rgbSimulated = rgbRadiance; rgbSimulated(rgbRadiance ~= 0) = log2(rgbRadiance(rgbRadiance ~= 0)); rgbSimulated(rgbSimulated < minLogExposure) = minLogExposure; rgbSimulated(rgbSimulated > maxLogExposure) = maxLogExposure; % Convert to RGB. rgbSimulated = uint8(255 * (rgbSimulated - minLogExposure) ./ ...                      sensitivity);
Posted in Color and Vision, Computing, Fodder for Techno-weenies, MATLAB, Photography | 1 Comment