DEBRIS.COMgood for a laugh, or possibly an aneurysm

First post in 9 days. I guess I could say I’ve been busy, but in fact I’ve been sitting here for 9 days with the most horrific case of writer’s block.

[another 2 hours go by]

See what I mean?

Tags:
posted to channel: Personal
updated: 2005-03-02 03:59:52

Newborns are endlessly cute. I have 1000 pictures to prove it.

Some of the close-ups suffer from uneven lighting. The built-in flash units on most consumer cameras have a limited range of use. In the case of my old Coolpix, arm’s-length “Speedlight” shots are rarely exposed well.

The image pictured here is underexposed in the area of interest. However, the baby’s sleeve is well-lit, and risks getting blown out if we correct the whole frame based on the lighting in the top half. Also, the image suffers from a red cast that is unfortunately typical of this camera.

Gradient masking provides a quick solution to the exposure problem: it allows me to apply a curve correction progressively across the image. In this case, a simple full-range gradient from top to bottom is adequate.

Note that no selections were made: this entire correction took about 60 seconds.

The exposure-correction curve is extreme. To allow for easy tweaking, I created it in an Adjustment Layer. To limit it to the top half of the image, I accessed the Curves layer’s “Layer Mask” by option-clicking on the layer mask thumbnail in the Layers palette. After selecting the Gradient tool and setting foreground and background colors to white and black (respectively), I dragged the mouse top-to-bottom to draw the gradient.

A second Adjustment Layer lets me pull the Red back in the highlights, to strip away the cast.

The resulting Layers palette shows both correction layers (although they’re disabled in this screenshot).

The resulting image can be seen in the right half of this before-and-after composite. Notice how the sleeve no longer competes with the face for your attention — yet there is no visible transition from the areas where a correction was applied to areas where no correction was necessary. Also, you’ll notice that the clothing is no longer pink.

For more Photoshop image-correction techniques, see the Photoshop channel.

Tags:
posted to channel: Photoshop
updated: 2005-10-24 05:45:16

After a few more nights of futzing with it, I settled on a solution to my phasing problem. Pictured is the current recording setup: two AKG C1000S mics centered above the middle of the dulcimer’s soundboard in a “coincident pair” arrangement.

It’s a compromise. I can get a better tone with different mic placement, but this is the only way I could get a phase-coherent signal. It seemed like a sensible compromise because tone is subjective, and transparent to the listener. In contrast, the phase problem would be apparent just by walking around the room.

So, yesterday I recorded approximately 500 notes*, or about half of my song. In sight: the end!

^*On a recent horrific commute, I held off brain death by a few minutes by counting the number of eighth notes in my song. This activity would be stupefyingly boring for most people, but I’d been stuck in traffic for five hours. Stupefyingly boring was a huge improvement. You could have re-leveled the blades of your planer with my EKG at that moment.

Tags:
posted to channel: Music
updated: 2005-02-22 04:33:26

In a presentation at the annual meeting of the American Association for the Advancement of Science, researchers announced compelling new evidence that human industrial activity is responsible for global warming.

The Chronicle’s Science Editor, David Perlman, who is such a legend that he has journalism awards named after him, summarized the findings in a piece headlined New global warming evidence presented Scientists say their observations prove industry is to blame:

But records show that for the past 50 years or so, the warming trend has sped up — due, researchers said, to the atmospheric burden of greenhouse gases produced by everything industrial, from power plants burning fossil fuels to gas-guzzling cars — and the effects are clear.

“We were stunned by the similarities between the observations that have been recorded at sea worldwide and the models that climatologists made,” said Tim Barnett of the University of California’s Scripps Institution of Oceanography. “The debate is over, at least for rational people. And for those who insist that the uncertainties remain too great, their argument is no longer tenable. We’ve nailed it.”

The Bush administration responded immediately by re-queuing its broken record: “The science of global climate change is uncertain,” said Bill Holbrook, spokesman for the White House Council on Environmental Quality.

I could have predicted this round of denials. Just two months ago, the U.S. delegation at the U.N.-sponsored International Conference on Global Warming “executed perhaps its most astonishing act of denial:”

Besides blocking all efforts to conduct substantive discussions, the U.S. allied itself with none other than Saudi Arabia in obstructing efforts to create a system of payments to help poor, low-lying island nations cope with the cost of mitigating damage related to global warming, such as rising sea levels, land erosion and increased storm damage.

A quote from Paula Dobriansky, the head of the U.S. delegation, illustrates just how far up its collective ass the Bush administration’s head is:

“Science tells us that we cannot say with any certainty what constitutes a dangerous level of warming, and therefore what level must be avoided.”

Most kids learn by age three not to touch the stove. They don’t know how hot it is. They can’t say with certainty what constitutes a dangerous level of heat. But they manage their uncertainty much more effectively than Bill Holbrook, Paula Dobriansky or George W. Bush.

Tags:
posted to channel: Conservation
updated: 2005-02-19 18:49:50

Prior to implementing the HTTP_REFERER blacklist described previously, I investigated the source of the faked HTTP requests. If they were all coming from the same place, I could simply block access from that address.

But the attacks are distributed: they come from many IP addresses on many networks. Here’s an example, showing the request count and source address for all hits to this site containing the work pokerin the past week:

nsa /var/log/httpd : cat debris_access_log | 
grep poker | awk '{print $1}' | sort | 
uniq -c | sort -rn | head
     91 65.165.84.11
     27 68.22.118.212
     20 12.172.137.13
     14 195.30.153.194
     13 38.223.231.8
     13 212.211.130.248
     12 203.199.92.158
     11 65.88.84.205
     10 168.11.16.22
      9 82.148.70.171

Just to confirm that the methodology above isn’t whacked, here are the faked REFERERs from the top IP address:

nsa /var/log/httpd : grep 65.165.84.11 debris_access_log | 
awk '{print $11}' | sort | uniq -c | sort -rn | head
      8 "http://www.nutzu.com/poker-hands.html"
      8 "http://www.nutzu.com/free-texas-hold-em.html"
      7 "http://www.nutzu.com/internet-poker.html"
      7 "http://www.nutzu.com/free-online-poker.html"
      6 "http://www.nutzu.com/world-series-of-poker.html"
      6 "http://www.nutzu.com/strip-poker.html"
      5 "http://www.nutzu.com/poker-tournament.html"
      4 "http://www.nutzu.com/texas-holdem-poker.html"
      4 "http://www.nutzu.com/rules-of-poker.html"
      4 "http://www.nutzu.com/poker-tables.html"

How could the referer spammers be operating from so many different networks? Here's my best guess: all those IP addresses represent Wintel machines that have been hijacked by viruses and trojan horses, and they're running distributed REFERER attacks without the knowledge of their owners. The machines are probably sending tons of spam email, too.

So when I previously said "this is all Google's fault," what I really meant is "this is all Microsoft's fault."

(In Microsoft's defense, they've only been working on making Windows more secure for two years... I'm sure they'll have some meaningful progress to report RSN.)

Tags:
posted to channel: Web
updated: 2005-02-19 07:30:28