Thursday, November 13, 2014

Eurographics is a European graphics conference! The review emails never make it clear what the scoring scheme is (it seems to be only published to reviewers). Therefore the ranges (for 2015) follow...

Overall Recommendation Score:

0 - 1 - very poor
1 - 2 - poor
2 - 3 - clearly below EG standard
3 - 4 - dubious - not quite acceptable
4 - 5 - marginal - only just acceptable
5 - 6 - acceptable
6 - 7 - good
7 - 8 - very good
8 - 9 - excellent

"An average of at least six is required for acceptance, but might not quite be enough."


0 - 1 - Very unconfident, really just a guess
1 - 2 - Rather unconfident, but I know a bit
2 - 3 - Moderately confident, I know as much as most
3 - 4 - Pretty confident, I know this area well
4 - 5 - Extremely confident, I consider myself an expert

Wednesday, February 19, 2014

Unwritten Procedural Modeling with the Straight Skeleton

...and a year later we have the every-so-slightly improved final thesis: (PDF) (latex source to follow)

Sunday, February 16, 2014

art from the code trenches

 One of the up-sides of programming graphics is that our bugs are art...

Sunday, May 05, 2013

Unwritten Procedural Modeling with Skeletons

The first complete draft of my thesis is now online (mirror 87Mb). This hasn't been submitted or viva'd yet, but may still be interesting to people. It's mostly a collection of posts from this blog, and the two papers I published about the straight skeleton.

I'm sure there's plenty of mistakes in it - let me know!

Monday, April 22, 2013

Vines are 5.5 seconds too long

There's a problem that's been bothering me for a while: how do we let users create consumable home video. If you've ever tried to use a video editing package, you'll probably have:
  • given up because the editor was hard to use (have you seen the edits people choose with Vine?...), or
  • given up because the editor couldn't import your footage, or
  • given up because the editor kept crashing, or
  • spent 10x the length of your final video, getting the clips lined up just right, or
  • had the result be entirely unwatchable to people who don't know your friend, Fred.
I went to Thailand, and being a geek, took 3 cameras and came back with way too much mediocre footage, ~30Gb, or 3 hours or so. Trying to edit it all to anything my friends would actually want to watch (or, fantastically, recommend someone else watch), would have taken a long time, and was probably beyond my skill level and hardware. My solution was to pick 0.5 second long section clips from each video. I was really quite pleased with the result:

This is actually a quite interesting 4 minute video, as far as holiday videos go. Possibly about 3 minutes too long, but pretty succinct.

The thing that really struck me was that the process of selecting the clip from the (sometimes quite long) clip was almost trivial, to the point where an algorithm could make pretty good guesses.
  • the first 0.5 seconds of a clip is a good default
  • ignore lots of frames of video that are the same (when I leave the lens cap on).
  • when not-much moves, and then something moves, that's what's interesting
  • however, if the view wobbles for 1-2 seconds at the start before going steady, that's me positioning the camera and you want the bit after.
  • changes in volume can be interesting.
  • blurry things generally aren't interesting
So then I started considering whether this would be a viable company. Let's call something like the above video a strobee (despite the fact the url was taken long ago), and each individual clip a bee.

So now we imagine a world in which everyone is uploading bees, from their phones, shiny new pairs of Google glasses (or do you wear a google glass?), cameras, etc... We pretty quickly come to the conclusion that strobees can, and should, be assembled on the fly from a large database. That is we could steam a strobee (endless video stream) to user based on:
  • users (user channels)
  • your current location (a stream that changes as you drive down the street!)
  • a particular location
  • most recent in time
  • a certain hashtag (#bobs_wedding, #election2015)
  • popularity (how do we judge popularity - votes? interaction with a stobee?)
  • colours (show me videos that are mostly red)
...there are enough possible use cases to warrant an expansive api.

There have to be a wide range of algorithms we can apply to public video feeds (nicely complying with the "substantiality of the portion" in american copyright law), to extract interesting bees. Strobee libraries might come from:
  • webcams
  • movies (imagine a 3rd party service that delivered a bee containing your chosen word from a random movie)
  • old fashioned TV streams
  • satellite images
Revenue seems to be a much simpler sell than twitter or facebook. We can limit ourselves to only showing 0.5 seconds of an advert every so often, targeted to the user, the search, or the location. Given that people will put up for anything for 0.5 seconds, addbees shouldn't be too much of a disincentive  There's always the option of paying to remove adverts. Since the adverts are part of the stream, we could let people embed strobees into other websites, or request a stream via an api without issue.

  • This blog post basically describes the Vine ecosystem, but with a lower maximum clip length. It would be trivial for Vine to compete. Then again, twitter competes successfully with email.
  • There's some deep technical work to do on compressing such short clips, the setup of the I-frames in certain short clips is problematic.
  • Can we compose a stream from a such a giant database in real time?
  • How do people give feedback on blink-and-you-miss-it bees?
  • We would want to disseminate everyone's clips, and show adverts along side them. Perhaps we don't show adverts to people who create popular bees? Should we ask (or set default to) a creative commons license for all bees?
  • If it were ever popular, people would use it for p0rn. How do we filter such short content? The ever-racist 70% pink/frame criteria? 
  • How does someone wearing google glass upload a strobee? We could take the 0.5 seconds before someone says "strobee"? (Until it became popular enough, then you would have people shouting "strobee" at you if you wore your google glasses into town).
  • A host of privacy/missing context lawsuits are likely...

Sunday, April 01, 2012

eurographics fast forward video

For a bit of light relief, here's the fast forward video for the Procedural Parcels paper that Carlos is presenting at Eurographics this month.

Saturday, December 24, 2011

back from Kaust

Kaust panorma

Before the holidays I had a short stint working out at GMSV@Kaust, King Abdullah University of Science and Technology in Saudi. I've written down a few notes about life at this crazy place:-

My initial impression was of the the amazing academic facilities. There are great offices, a visualization suite, 3d printing facilities and a super computer (which they seem to be trying to find a use for). As you'd expect for a university with a $10bn endowment, the buildings are beautiful - sweeping open atriums and harbour-views from many of the offices.

The campus itself has the feel of American suburbia - all speed bumps and sprinklers. Very nice, very liveable, but a little fake if you're European. While I was there I lived in several places -
  • The Kaust Inn (photos) - the campus hotel, same as any hotel anywhere. Watch out for the rooms at the back which point towards the grand mosque and its 5.30am prayer calls.
  • A one bedroom flat (photos) - A one bedroom flat on the island. Loads of space for entertaining guests, a good sized kitchen, and a study. Plenty enough room for a (European?!) couple.
  • A four bedroom house (photos) - Towards the end of my stay the research group rented one of the big colonial-style houses on the beach. (Due to some technicalities I had it to myself for most of my time there). This is a fantastic place that would normally be reserved for full Professors and their families. A sofa for every day of the week, waking up to eat breakfast overlooking the beach and the waves breaking on the reef.
The university has done a fantastic job of marketing and advertising itself. It is hard to find something on campus that isn't branded with the university's "unity seeds" logo.

Kaust made me reassess one of my old prejudices - old universities are good universities. Although I must have always realised that this was false, this place is a brilliant data point proving the contrary. The campus is three years old, has a formidable faculty and has forged (bought) alliances with the great and the good (CambridgeCornell, Oxford, Stanford...)

I think a spell at Kaust would look very good on anyone's CV. In particular for people looking for a fast track to high level research, or as a cheap way to get a graduate degree (the two year long Master's courses comes with a ~USD2000/mo scholarship).

There's several moral considerations that people should be concious of in Saudi. As well as the well known country-wide issues of civil liberties, LGBT, and women's rights (which are better documented elsewhere), there are also issues that are very pronounced on Campus -
  • I was also surprised at how many times I had to sign a bit of paper that threatened to kill me. Both the visa and customs paperwork make it clear that the death penalty is in use. While slightly tarnishing the Arabian hospitality of lore, this is still true of plenty of other countries (cough cough USA). This was something that was always in my mind when travelling to Saudi and added to the traveller's anxiety more than it should. My concerns seem to be unfounded - Sharia law isn't enforced on the campus, and I'm sure that 90% of the academic staff would quit if anyone lost a hand after being accused of theft (writing of the investment in the universitiy overnight).
  • The campus is kept clean and spotless by an army of (relatively) poorly paid foreigners. Mainly Indian and Filipino; These guys are driven in from Jeddah every morning, or live in gritty looking housing on the other side of campus. I guess while I realise that the world is a very unfair place, and I have my share of sweat-shop trainers, I wasn't expecting to have this reality thrown at me every day.
    employee housing?

  • Saudi is historically suspicious, if not outright hostile, to outsiders. I did find myself asking if this kind of knowledge transfer is really moral if the country doesn't want to integrate with the rest of the world. For example there are no tourist visas available to Saudi, unlike many other Middle-Eastern countries, and most of the foreign workers find themselves living in gated communities away from the locals. The attitude to foreign workers seems to work, get paid, stay quiet, then get out.
  • However green the campus claims to be, the building refuse discarded on the other side of the motorways says otherwise. It is very unnatural to live the (24-7-air-con) American dream in the middle of the desert, and however well designed the campus' buildings are, there must be a significant environmental cost. Add to this the 100 mile drive to escape the campus, or air travel to escape the desert (at regular intervals if you want to remain sane), and it is possibly not the most environmentally sound living location.
The campus is modeled on American suburbia - after you pass the tank traps and security checks you find yourself in a very safe feeling environment. Palm trees (watered by the eternally present sprinkler systems) line the streets, and there's plenty of green open spaces (a couple of parks and a golf course). Being an engineering university, the male:female ratio is quite distorted. The supermarket is 15 minutes walk from anywhere on campus and is stocked to placate people from most parts of the world - Froot Loops for the Americans, Leerdammer and Emmental for the Europeans, a reasonable wheat-free section and even beef-bacon for those with pig-withdrawal symptoms. Of course there's no beer, and occasional supply problems (the campus ran out of peanut M&M's!). Most critically, there was no dark chocolate - a certain prerequisite for doing research of any quality...

The feeling of cargo-cult westernism seems to permeate a lot of the campus. For example the workers in the supermarket wear disposable gloves when working with raw meat, but don't take the gloves off to pass you a piece of cheese. The fast food places in the malls in Jeddah (90 minutes on the frequent Kaust buses) are the slowest I've ever seen. The airport is another great example - there's been no checks for liquids, and was marched in a group of 20 passengers backwards through security (and the metal detectors) after a flight was cancelled. There's also the occasional path to nowhere, or bathroom sinks positioned to make the toilet impossible to sit on if you're over 5ft tall. This is a great blog detailing life on the early Kaust campus, including the epic floods!

My number one gripe was the feeling of being stuck on campus. As a gated community, there was a lot to do on the campus - a medium sized gum, windsurfing, snorkling trips, and a coed (racy!) beach. People who had families, and spent their time socializing with (sober) friends, seemed to get on fine with the setup. However I'm used to heading out at weekends and blowing of steam on 150km bike rides, and there was nothing that I found to come close to this - the roads were too large (and unsafe - almost all the cars looked like they'd been in some sort of collision in the last 6mo) to cycle on, and there were no real organised outdoor activities (no hiking, orienteering, or even yachting). If you so much as sail the rental dingy more than a few hundred meters from the beach, the coastguard comes and picks you up. While there's a great choice of stuff to do on campus, it is just that - a choice between several watersports. After a few weeks, all this left me feeling more than a bit trapped.

Still, when all is said and done, Kaust (not to be confused with ECUSTHKUST, KNUST or KUST) is a refreshing change to trying to do academia in the UK, where career advancement is difficult and basic funding is in question after the government pulled funding for most of the mathematics postdocs. The campus, and its sunsets, are really beautiful, and well worth visiting!

Moon, Beacon