Photo (c) Jan Trutzschler von Falkenstein; CC-BY-NCPhoto (c) Rain RabbitPhoto (c) Samuel CravenPhoto (c) Gregorio Karman; CC-BY-NC


I am a research fellow, conducting research into automatic analysis of bird sounds using machine learning.
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I live in Tower Hamlets, the London borough with the largest proportion of Muslims in the UK. I see plenty of women every day who wear a veil of one kind or another. I don't have any kind of Muslim background so what could I do to start understanding why they wear what they do?

I went on a book hunt and luckily I found a book that gives a really clear background: "A Quiet Revolution" by Leila Ahmed. It's a book that describes some of the twentieth-century back-and-forth of different Islamic traditions, trends and politics, and how they relate to veils. The book has a great mix of historical overview and individual voices.

So, while of course there's lots I still don't understand, this book gives a really great grounding in what's going on with Muslim women, veils, and Western society. It's compulsory reading before launching into any naive feminist critique of Islam and/or veils. I'm sure feminists within Islam still have a lot to work out, and I don't know what the balance of "progress" is like there - please don't mistake me for thinking all is rosy. (There are some obvious headline issues, such as those countries which legally enforce veiling. I think to some Western eyes those headlines can obscure the fact that there are feminist conversations happening within Islam, and good luck to them.)

A couple of things that the book didn't cover, that I'd still like to know more about:

  1. The UK/London perspective. The book is written by an Egyptian-American so its Western chapters are all about things happening in North America. I'm sure there are connections but I'm sure there are big differences too. (I am told that Deobandi Islam is pertinent in the UK, not mentioned in the book.)
  2. The full-covering face veils, those ones that hide all of the face apart from the eyes. Ahmed's book focuses mainly on the hijab style promoted by Islamists such as the Muslim Brotherhood (see the photo for an example of the style), so we don't hear much about where those full face-coverings come from or what the women who wear them think.
books · Permalink / Comment

The Long Mynd is a range of hills in Shropshire. Very beautiful area this time of year. Lots of birds too. People often comment on the birds of prey: the buzzard, red kite and kestrel, soaring silently above and occasionally plummeting to pounce on something. Of course I'm more interested in the birds making the sounds all around.

I was most taken by the meadow pipits - as you walk around on the Mynd, they often leap surprised out of the heather and flitter away making alarmed "peeppeeppeep" sounds (or maybe more whistly than that, "pssppssppssp"). I saw a skylark too, ascending from the ground about 20 metres in front of me. It's great to witness it when they do that: an unhurried circling ascent, all the while burbling out their famously complex melodious song, like a little enraptured fax machine going to heaven.

While hanging around in the forest I noticed how many non-vocal bird sounds you can hear. The most common example is wing flutter sounds, I heard them from lots of different species, and the sound can often be very deliberate. The most surprising sound of all was when I was walking past a tree and heard a knocking sound and I thought, "Oh, is that a woodpecker starting up?" - but it wasn't. I could see the little bird on a branch a few metres away and it was a coal tit, doing a bit of a woodpecker impression. It would peck at the branch hard, about four times in a row, repeatedly, giving me the impression it might have been trying to do some DIY of some sort. It also tried it on a second branch.

Lots of gangs of ravens around too - their curious adaptable calls reminding me of the ones I saw recently at Seewiesen. I often heard (from a distance) the song of the nuthatch - that nice simple ascending note that I first encountered when camping in Dorset. Now and again a jay, lovely orangey and cyan colouring contrasting with its raspy magpie-ish yell. The jays seem to be shy around here, unlike the one that used to hang around in our garden in London.

Of course all the usual gang was there too: lots of robins singing, jackdaw, magpie, wren, house sparrow, blackbird, stock pigeon, one wood pigeon, the occasional chiff chaff. I think I heard a goldcrest at one point but I'm unsure. One willow warbler down by the reservoir.

birds · Permalink / Comment

Our journal paper Detection and Classification of Acoustic Scenes and Events is now out in IEEE Transactions on Multimedia! It evaluates many different methods for detecting/classifying in everyday audio recordings.

I'm highlighting this paper because it covers the whole process of the IEEE DCASE evaluation challenge that we ran a little while ago, with many international research teams submitting systems either for audio event detection or audio scene classification.

It was a big team effort, with various people putting many months of time in, from 2012 through to 2015 (even though it was essentially an unfunded initiative!). Specific thanks to Dimitrios and Emmanouil, who I know put lots of manual effort in, repeatedly, to get this right.

science · Permalink / Comment

The International Bioacoustics Congress 2015 was a fantastic conference. Lots of fascinating research, in a great place (Murnau, Bavaria, Germany), and very well organised! In this note I want to capture some thoughts that it triggered, about the practical organisation of a conference.

The staff that faciliated the conference made it run very smoothly. There were helpful people in the downstairs office almost all week, to ask questions etc. I particularly appreciated the facilitation for conference speakers: downstairs, the organisers loaded our presentations onto the laptop and checked they worked; then upstairs, there was a sound engineer who very efficiently fitted us with the radio mic and opened the presentations. This kind of support was crucial to make it possible to have such a busy schedule: many sessions had only 15 minutes per speaker! So no time for messing around.

Various IBAC people said, and I agree, that it's vital to keep it as a single-track conference: that seems to be part of its friendly community atmosphere. This is tricky, as IBAC has grown so that the schedule is now tightly-packed, and one "easy" way to reduce the pressure would be to go multi-track. I suspect the biggest risk there is of splitting the community into taxa (birds, marine, anurans, etc). So if parallel sessions were to be used (not my preferred solution), it'd be better to do that with the "open" rather than themed sessions, as someone at the AGM suggested. (The mix of open and themed sessions was well-balanced here in 2015.)

Every day opened with a 60-minute keynote, which is a great and widely-used pattern. We then had 20-minute slots in the themed sessions, and 15-minute slots in the open sessions. In my home discipline I've never seen 15-minute talk slots, and I think that's too short. I think that 20-minute slots are good, as long as the chair insists on keeping some time for questions, since I personally believe that public discussion with conference speakers is a really important part of what conference presentations are for. The IBAC chairs didn't insist on this at all really, which is a shame. That aside, they were well hosted.

The poster sessions were lively and very interesting, but physically they were too full! It was often very difficult to even read the titles of posters, let alone talk to the person standing there, if one or two people were discussing a nearby poster. This could have been improved by having 4 separate sessions of 40 posters, rather than 2 sessions of 80 which were each repeated for two days.


So, as I've already implied, IBAC was very highly subscribed, with many talks and posters, and I've been suggesting it could be better if the programme was a bit less tightly-packed. How could this be done (without going multi-track)? One answer is to be more selective, i.e. to accept fewer abstracts. Immediately I want to highlight a risk of this: it's great at IBAC to have lots of student and early-postgrad presenters, so we would want to avoid a selection process that favoured big names or experienced abstract-submitters. (We'd also want to maintain a decent balance across taxa.) I'd suggest a simple quota: minimum 50% student or recently-graduated people, both for talks and for posters.

Being selective has a cost: interesting things get rejected. The quality of IBAC 2015 was high, there's no need to be selective for quality purposes. IBAC is currently every two years. I wonder if the IBAC community would be interested in having IBAC every year? There's clearly enough content for that. Would it suit the rhythm of the community? Could the IBAC steering committee cope with the doubled workload?


I find a printed programme absolutely essential. The 2015 organisers decided that many people don't want it because they use electronic versions, so printing it would be wasteful. That's fine, but for me and many others we need something. I think ideal would be simply to have a tick-box on the conference registration form, "Would you like a printed programme?" Simple to handle, and reduces unnecessary printing.


A few other miscellaneous thoughts:

Of course almost everything I've written is about general conference organisation, not just IBAC. These thoughts are spurred by conversations we had at IBAC, and spurred by the overall extremely good conference organisation. Massive thanks to the IBAC 2015 organisers and staff!

P.S. I previously blogged about the research at IBAC 2015.

science · Permalink / Comment

The International Bioacoustics Congress 2015 was a fantastic conference. Lots of fascinating research, in a great place (Murnau, Bavaria, Germany), and very well organised. Here I'm making some notes on the interesting research topics I encountered. I can't list everything because almost everyone at the conference was doing something fascinating! What a niche this is ;)

This was my first IBAC. I'd say the majority of people were animal communication or animal behaviour researchers, plus ecologists, sound archivists, a composer or two, a couple of industry people and a couple of computer scientists. (I didn't spot any acousticians/physicists, I was wondering if I would.) Lots of great people talking about animal sounds.

My own presentations went down well, I'm pleased to say. I had a talk about our Warblr bird sound recogniser (here's the journal paper, Stowell and Plumbley (2014)), and a poster about inferring the communication network underlying the timing of animal calls. (From the latter, lots of good conversation about whether cross-correlation was a good tool for the job. My answer is that it's perfectly fine for pairs. For larger groups it's tolerable if you have enough data, but I have a better way... need to write it up.)

My colleague Rob Lachlan presented his really neat work on vocal learning in chaffinches. Apparently chaffinch syllable transmission is one of the most precise cultural transmission processes that's yet been quantified. I'd imagine he could tell you more about how that might relate to questions of the birds' innate biases etc.

Now here are some good things that were new to me. (Note that I'm quite a bit biased towards birds rather than the other taxa.) I'll save all the zebra finch items until the end since they're interrelated and something I'm currently thinking about. First, miscellaneous highlights:

Now the zebra-finch-based research:

To all at IBAC: my apologies if I misrepresent you here, missed you out, or misspelt your name! In particular I didn't manage to see much of the second poster session since I was myself presenting a poster.

At the end of the conference there was an organised visit to MPIO Seewiesen, where a lot of good bird studies are happening. I was most struck by the magnificent ravens, living in outdoor aviaries and showing off their awesome vocal skills.

What else? Well, lots more. A great hike organised in the wetlands around Murnau (Murnauer Moos). Bavarian beer and food. The mountains as a backdrop...

science · Permalink / Comment

So, our Warblr bird sound recognition app has been out for almost a month, and we've had many thousands of people using it and submitting bird audio recordings (thanks!). We've also had lots of great reviews in the consumer press. (Listen to this evocative piece on BBC Radio Scotland, fast-forward to 1hr 43.)

One thing which we knew was going to happen was that some people would demo it by playing back sound recordings into the mic, rather than recording actual birds. After all, sound recordings are easier to grab... What I didn't realise, from my own perspective, is that people would think this was a good way to test the app.

Playing back recordings is usually a really bad way to test the app, or any sound recognition app really, because recorded sounds differ in many many ways:

All of these things make the audio drastically different from a genuine direct recording, even though our human ears are clever enough to understand the correspondence. Yes, ideally a system would be as clever as our human ears, but that's for the future. (Note the difference from a product like Shazam, which recognises recordings but does not recognise the real live musician... interesting eh!)

Plus there's yet another aspect to consider: we make use of your location to help determine what kind of bird is likely. This is thanks to the BTO whose amazing crowdsourced bird data helps us know which birds to expect where and when. So, if you're playing a sound file that isn't native to where you are, our system is doubtful that the bird is there... and quite rightly doubtful, perhaps.

I can't emphasise enough that playing back recorded sounds is not the best way to test. We can't prevent people from doing this, of course! That's fine, but always bear in mind that you didn't test it in proper field conditions, only at your desk. You're not testing a bird recognition app if you're not testing it against real wild birds...

sound · 2 comments

A baked germanic cheesecake with blackberries and lemon curd. Yes please. Makes a cheesecake for 12 slices.

Cheesecake, artist's impression

Put the oven on at 180C. Line a round springform cake tin (7" diameter maybe) with greaseproof paper.

Crush the biscuits roughly in a bag, and melt the butter/marge in a pan or in a microwave. Mix the biscuits and butter/marge well then press it into the tin, forming an even base all the way to the edges. Put in the oven for 10 minutes, then take it out and leave it out to cool. If you have time, put it in the fridge for up to an hour to firm up.

Turn the oven down to 140C.

Beat the quark, cream cheese, icing sugar and two egg yolks together.

Whisk the egg whites to stiff peaks. Then fold them gently into the quark mixture, with a wooden or plastic spoon, taking care not to over-mix (which would take the air out).

Now to assemble the thing in layers:

  1. Pour one-third of the quark mixture or less (a quarter?) onto the biscuit base. (I say "or less" because you want to be sure you have enough left to do the very last layer, it's important for it to be on the top.) Smooth the layer out flat.
  2. Then put the lemon curd on top of the mixture - it's quite blobby and thick so it'll be hard to get an even coating, and you wouldn't want that anyway - but try your best to get a fairly even sprinkling of tiny blobs all over, and don't try smooshing it out afterward cos it won't work.
  3. Then another one-third of the quark mixture. Smooth it out evenishly.
  4. Now sprinkle the blackberries over the top. You do NOT want to make a complete covering, because structurally you don't want the blackberries to keep the top quark layer from meeting up with the lower quark layers. So don't pack them too tightly, and only do one layer.
  5. Finally the rest of the quark mixture. Again, smooth the top, if you want. The important thing is to have quark mixture all over the top, hiding the blackberries from the oven.

Now bake this in the oven, for about 90 minutes. (Cooking slowly, at 140 rather than 180, is so that it doesn't brown on top, or at least not much.) Turn off the oven and let the cheesecake cool in the oven, with the door ajar (cooling it slowly helps prevent cracking, though when using the blackberries it's quite unlikely you'll avoid all cracking). Refrigerate.

Serve with some blackberry coulis if you have more blackberries! Not necessary though. It's great as-is - ideally you should get it out of the fridge a while before you eat it so it isn't too chilly.

recipes · Permalink / Comment

What tracks would you take into a shop to test out a hifi?

FWIW here's what I'm thinking.

music · Permalink / Comment

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