Enhance

Forgive me for saying so, but I know a thing or two about enhancing photographs. I’ve put some time in as a satellite and aerial imagery analyst, and as a hobby photographer I make no apologies about Photoshop. I grok histogram response curves, level shifting,  global  and local contrast, interpolation, headroom, falloff, edge detection, hue isolation and saturation expansion. I know you almost always zoom out (!) to see a pattern, but if you want to get into pixel-peeping, I know a little about decomposing a pixel into constituent spectral signatures, k-means clustering and machine-learning classification, and all the lovely supervised and unsupervised pixel binning techniques. If I give myself an hour to study up, I can even keep the Minimum Noise Transformation straight in my head for 15 minutes. And the N-Dimensional Visualizer speaks for itself.

There is an enormous amount you can do to make a shape or pattern or shade of interest stand out in a image, by tweaking the colour or contrast response, or exploiting extra parts of the light spectrum to help the computer find hidden colours. You can fuzz together noisy patterns to see the shapes behind them, or bin together multiple pixels to lighten up the darkness. Just about the only thing you can’t do is create detail where there wasn’t any to begin with.

So I get grumpy every time I watch a movie with an image analysis scene, and the one and only thing they always always do is the one damn thing you can’t.

dunk3d made a montage:

Two they left out:

Bladerunner (the original?)

and of course Super Troopers

…(although it’s true that imagery analysts wear state trooper uniforms to operate their computer terminals.)

3 comments:

i’ve always thought the same thing with audio enhancing, and have wondered if maybe i was missing something and there were special filters that managed to separate sounds that co-mingle in the same frequency range. maybe there’s a tiny bit of truth to it but almost every film dealing with the subject seems absurd.

i’m not as knowledgeable with the visual side of things but assumed it was similar. haha thanks for the super troopers clip, too funny.

I was watching The Good Shepherd recently, which is about the origins of the CIA. There’s a recurring scene where some technicians are trying to pick up clues from a grainy photo and an accompanying audio tape recorded in a hotel room. The photography analysis is actually somewhat convincing: they try and use their own brains to do pattern analysis on what are inevitably fuzzy shapes. But the audio analysis bit is, as you say Pete, absurd. They somehow take an analog tape and run it through analog frequency isolation equipment in order to remove sounds which have been recorded over the tape, which reveals normal-sounding full-frequency church bells in the background. Huh? They isolated frequencies in order to remove taped-over sounds? I find this kind of ridiculousness just kills the tension. It’s like when the Enterprise is saved yet again by some inversion of the tachyon pulse whatever. If there’s no rules, who cares what happens?

I agree! Nothing irks me more than that! Came across your blog while looking for hydrology data.

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