Wednesday 1 July 2015

TRIX WITH PIX

Dick Pountain/Idealog 246/06 January 2015 14:05

My major digital pastime has for several years now been photography rather than programming: reading my profile reminds me I joined Flickr eight years ago and have now posted 1500+ pictures there (www.flickr.com/photos/dick_pountain/). The digital imaging market has been through a technical revolution during those years, and now faces what tech gurus love to call "disruption" thanks to the mobile phone. A whole generation now prefers their mobile to a proper camera, and phones' performance has improved extraordinarily by incorporating sensors and image processors from real camera manufacturers like Sony. Camera makers are striking back with gorgeous-looking retro designs that recall the golden age of the Leica, fitted with huge sensors, fixed "prime" lens and astounding image quality - and premium £1000+ prices aimed at separating "real photographers" from selfie-snappers.

As for me I've resisted both these trends. I started out posting mostly travel pics, street photos and landscapes, over-sharpening and saturation-boosting them to match the approved Flickr aesthetic, but in recent years I've become more and more interested in post-processing photos to make them more like paintings (abstract or otherwise). There are plenty of software tools available nowadays to spice up photos - some like Google's Nik Collection of plug-in filters for Photoshop and Light Room are very good indeed - but I'm less interested in buffing up my pics than in dismantling and reconstructing them completely. And my chosen tool is therefore, er, Photoshop Elements version 5. This ancient version lacks all the smart cut-out and similar features of later versions, and many abilities of full Photoshop, but it has all I want which is basically layers, blend modes and a handful of filters.

My modus operandi is as eccentric as my choice of platform. I perform long sequences of operations on each picture, duplicating and saving layers, tinting, filtering and blending them in different modes, but rather than write down this sequence so I can repeat it I deliberately do *not* do that. I merely watch the continually changing image until I like it well enough to stop. I can never repeat exactly that effect again, which I've convinced myself makes it "art" rather than mere processing, just as an oil painting can never be exactly repeated. Doing this so many times has given me a fairly deep grasp of how pictures are made up, about manipulating different levels of detail and tonality. One of my favourite filters is High Pass, which can separate out different levels of detail so that you can enhance or remove just that level. Another favourite trick is mixing some percentage of an outrageously processed image back into the original to temper the effect and make it more subtle.

In view of all my coal-face experience of the internal makeup of digital pictures, I was interested to hear about a joint project by GCHQ and the National Crime Agency (NCA), announced in December 2014 by PM Cameron, to deploy new recognition algorithms for identifying online pictures of child abuse, to aid in their prosecution. The press release said these algorithms are "hash based": that is, they process the bitstream of a digital picture to reduce it to a single number that becomes a "fingerprint" of that picture. Such fingerprinting is essential for evidence to be acceptable legally: it's necessary to prove that a picture confiscated from some offender is the same as one obtained from someone else, and obviously filenames are of no use as they're only loosely attached properties that can be easily changed.

The US website Federal Evidence Review suggests an algorithm called SHA-1 (Secure Hash Algorithm version 1) is in use for this purpose, but it appears to me that algorithm is designed for use on texts, gun serial numbers and other alphanumeric data sets, and I can hardly believe it would generate useable hashes from bitmapped images whose contrast, saturation, sharpness and so on may have been altered - either deliberately during enhancement, or merely by accident through repeated sloppy copying of JPEGs. Pictures that are perceptually similar might have bitstreams quite different enough to change the hash.

I'd guess that content analysis, not merely hashing the bits, will be needed to prove the identity of two versions of any bitmapped image. Face recognition is well advanced nowadays (recent compact cameras can even distinguish smiles) and so is dissection of bitmaps into separate objects in Photoshop. It would remain challenging to create a unique hash from the collection of persons, furniture and stuff isolated from each picture, and oddly enough it's in fine art rather than criminology that the required expertise is most advanced. Iconclass is a hierarchical notation developed by Dutch painting scholars for cataloguing unique configurations of picture elements, and what's needed is something similar for far less salubrious subject matter.  

THE EMOTION GAME

Dick Pountain/Idealog 245/05 December 2014 11:02

In Viewpoints last month Nicole Kobie fairly skewered ("Good at PCs? It doesn't mean you're bad with people") Hollywood's sloppy assumption that Alan Turing must have been autistic because he was a mathematical genius who didn't like girls. I almost didn't go to see "The Imitation Game" for a different reason - the sensational trailer that seemed to be trying to recruit Turing into the James Bond franchise - but I forced myself and was pleasantly surprised that although it took some liberties with the facts, it did grippingly convey the significance of Bletchley Park to the war effort. The movie's major "economy with the truth" lay in excluding GPO engineer Tommy Flowers, who actually built the kit and wrestled with those wiring looms that Turing was portrayed as doing alone. (It also lumped together two generations of hardware, the "Bombes" and Colossus, and barely even attempted to explain Turing's seminal paper on computable numbers, but those I excuse as they'd have hugely slowed the pace).

The film doesn't mention Asperger Syndrome - just as well since it was unknown in Turing's lifetime, and we now have to call it autistic spectrum disorder anyway - but as Nicole pointed out Cumberbatch's depiction of Turing was clearly based on modern notions about the stunting of emotional expression and social interaction that comprise that disorder. The plot depends heavily upon Turing overcoming the dislike his coldness provokes in the other team members, assisted of course by the token emotionally-literate woman played by Keira Knightley, and the tragic ending shows Turing being chemically castrated by injections of female hormone. And that combination of emotions with hormones set me off to read between the lines of The Imitation Game's script to a deeper meaning which the writer may or may not have intended.

The film is named after a test of machine intelligence that Turing invented, in which the machine must try to imitate human conversation sufficiently well to fool another human being, on the assumption that language is the highest attribute of human reason. However recent research in Affective Neuroscience has revealed the astonishing extent to which reason and emotion are totally entangled in the human mind. The weakness of the whole AI project, of which Turing was a pioneer, lies in failing to recognise this, in its continuing attachment to 18th-century notions of rationalism. Those parts of our brain that manipulate language and symbols are far from being in ultimate control, and are more like our mind's display than its CPU. I am, therefore I think, some of the time. US neuroscientist Jaak Panksepp has uncovered a collection of separate emotional operating systems in the brain's limbic system, each employing a different set of neurotransmitters and hormones. These monitor and modulate all our sensory inputs and behaviour, the most familiar examples being sexual arousal (testosterone and others), fight/flight (adrenaline) and maternal bonding (oxytocin), but there are at least four more and counting. What's more it's now clear that motivation itself is under the control of the dopamine reward system: we can't do *anything* without it, and its failure leads to Parkinsonism and worse. Now add to this the findings of Antonio Damasio, who claims all our memories get tagged with the emotional state that prevailed at the time they were recorded, and that our reasoning abilities employ these tags as weightings when making all decisions.

These lines of study suggest two things: firstly all rationalist AI is doomed to fail because the meaning of human discourse is permeated through and through with emotion (if you think about it, that's why we had to invent computer languages, to exclude such content); and secondly AI-based robots will never become wholly convincing until they mimic not only our symbolic reasoning system but also our hormonally-based emotional systems. Sci-fi authors have known this for ever hence their invention of biological androids like those in Bladerunner, with real bodies that mean they have something at stake - avoiding death, finding dinner and a mate (a bit like the IT Crowd). Steven Hawking's recent grim warnings about AI dooming our species should be tempered by these considerations: however "smart" machines get at calculating, manipulating and moving, their actual *goals* still have to be set by humans, and it's those humans we need to worry about.

So as well as a great deal of pleasure from its serious treatment of Turing, the two big lessons I took away from The Imitation Game were these:  machines will never be truly intelligent until they can feel as well as think (which would depend as much on advances in biology as solid-state physics and software engineering); and it would be nice if they were to start planning an "Imitation Game 2: The Tommy Flowers Story".

SOCIAL UNEASE

Dick Pountain /Idealog 350/ 07 Sep 2023 10:58 Ten years ago this column might have listed a handful of online apps that assist my everyday...