And with everyone’s spirits kept high, it means that when the evening activity kicks off, you have the most awesome audience you could possibly hope for. Big ups to TMC for the video, m0d for the other video which should be surfacing soon, Ziphoid for streaming the gig on SceneSat Radio, and of course Havoc, D-Force and the rest of the Outline team for making it all happen…

Setlist

• 1:51 Gasman – Out Of Neverland
• 6:18 Gasman – Torch Dragon
• 8:41 Celine Dion – My Heart Will Go On
• 10:23 Gasman – Cybernoid’s Revenge
• 14:23 Madonna (arr. TDM + Factor6) – Hung Up
• 20:17 Gasman – Oldskool Crusader
• 23:47 Michael Jackson – Thriller (featuring Okkie)
• 30:30 Purple Motion (arr. TDM + Factor6) – Satellite One

balls, touching

And after all that, I still had some spare energy to do some casual hacking around with sine waves and come up with an entry for the 128 byte intro compo. As you’ll see from the video, 128 byte intros are one of those peculiarly demoscene-ish things that demand a certain frame of mind to be enjoyed properly, to the point where it gets a tad surreal for outsiders. If nothing else, you can certainly count on the Outline audience to provide a soundtrack to a silent production.

balls, touching on Pouët

(…and before you ask, the title does indeed come from an infantile demoscene in-joke about genitalia. I’d actually only planned for there to be one ball, but then one of those fortuitous coding accidents from adding or removing an odd instruction happened, and I knew I had to run with it.)

• jasmid on Github
• Online demo

Read on for the complete notes/transcript of the talk (in hopefully more coherent form than the talk itself – next time I promise to spend less time on the flashy demo and more time figuring out exactly what I’m going to say…)

Right now everyone’s jolly excited about the HTML5 audio element. At last we have a standard-compliant way to drop audio clips into web pages that avoids all the gunk with external plugins and replaces it with a simple tag (well, once you’ve fought through the details of which browsers support MP3 versus Ogg anyway). It has a comprehensive API to handle all the details of buffering, programatically pausing, playing and skipping and so on – but one thing it stops short of is being able to generate the audio data on the fly, within the browser.

Why would you want that? Well, I can’t say why you’d want it, but I can tell you what I’m hoping to do with it: I’m involved in the demo scene, a community of programmers, artists and musicians who create digital art – something roughly like music videos, but with visuals generated in real time – and I’m working on a forthcoming website that will showcase those productions. This community originates from the days of the Commodore 64, when people cracked games and added little intro animations to promote themselves, which became more and more elaborate as rival groups tried to outdo each other, until they evolved into full-scale artistic creations and the game cracking side of things took a back seat. And among the artefacts to come out of this community is a hell of a lot of music – we’re talking hundreds of thousands of tracks, all preserved in the native formats of the Commodore 64, and the Amiga, and all sorts of other things. And it would be quite neat to be able to play all of these from within my website.

I’m using this site as an excuse to play around with cool technologies, and at first I figured that this was an ideal job for Amazon EC2 – set up a bunch of instances churning away in the background converting these files to MP3. However, when I started to learn about ways to generate audio in the browser, it made sense to take advantage of that and save myself a whole lot of up-front processing (not to mention bandwidth).

At the forefront of this new development is the Mozilla Audio Data API, available in the latest nightly builds of Firefox. This extends the HTML5 audio API with a few new methods, the central ones being mozSetup – which allows you to initialise an empty audio stream with a specified sample rate and number of channels – and mozWriteAudio, which lets you pass in an array of floats representing some sample data to add to that stream. Like all good up-and-coming browser innovations, we can reasonably assume that once the Mozilla developers have got this API stable enough they’re going to submit it to WHATWG for inclusion in the HTML5 spec – but for the moment, it has somewhat limited adoption. There is a remedy for that though…

At my last Barcamp London, two years ago now, I gave the first public showing of JSSpeccy, my ZX Spectrum emulator written in Javascript, which has been something of a runaway internet hit – and I’ve been somewhat surprised by the number of people taking it seriously, rather than as the crazy pointless hack I built it as (not least, the guy who ripped it off and sold it on the App Store as the first ever iPhone Spectrum emulator, despite it running at about 30% speed *cough*). But one guy who’s picked up the concept of emulation in Javascript and taken it much further than I’d ever dreamed possible is Ben Firshman, who created JSNES, the Javascript SNES NES emulator, featuring a whole host of advanced optimisations and new features, including audio support.

To achieve this, he created the dynamicaudio.js library, which sits on top of Mozilla’s Audio Data API, but also provides an invisible Flash widget for other browsers to fall back upon. Armed with this work, I was able to build the first step towards my goal: jsmodplayer, a player for the MOD music format originally introduced on the Amiga. It’s a rather messy format to implement, with every man and his dog coming up with their own custom extensions to it in a very ad-hoc way, but at its heart it consists of a set of uncompressed wave samples (typically a second or two in length), and a script detailing when to trigger them and at what pitch. Put enough of those trigger events together, throw in some effects like volume control and pitch slide, and you have a song.

Now, as we all know from the Apple versus Adobe tiff, Flash is not exactly universal across the platforms we care about – so we haven’t covered all of our bases yet. However, for certain applications, there’s a possible third path (albeit one that I haven’t properly investigated yet), using another recent browser addition: data: URIs. Unlike typical URLs, which point to some external location that contains the data we want, a data: URI embeds that data directly, as a string of base64 or URL-encoded data. This means that we could generate a string containing a valid WAV file from Javascript (or indeed an MP3 or Ogg file, although generating those from Javascript is a little bit hardcore), and use that as the source of an <audio> element.

This does depend on us being able to generate the audio up-front before starting playback, so it’s arguably not truly ‘real time’ – something like an emulator, which is generating audio in response to user interaction, couldn’t really do this. It’s good enough for our straightforward audio player, though.

For a while there was an unfortunate flaw in this plan: Chrome didn’t currently support WAV as an audio format. The bug tracker ticket relating to this featured some rather flimsy arguments defending this decision, such as “if we support WAV, people will start widely serving audio across the web as uncompressed WAV files” (um… just like everyone on the internet is using BMP files, which are supported by all major browsers, right?). Given the tendency of bug tickets to wander off onto unrelated subjects, it’s hard to tell what the eventual conclusion to this is – but if I’m reading it right, we can happily use WAVs as of Chrome 7.

(At this point, someone rightly mentioned that Internet Explorer imposes a 32K limit on URLs, so that won’t get you much of a wave file – especially with base64 or URL encoding to contend with. As such, all we can really do is hope that IE users will tend to have the Flash option available. Personally, I think it makes a refreshing change that we can even consider IE in our cutting-edge browser hacks once again…)

In fact, there’s another mechanism for feeding data into URLs dynamically, which I’d all but forgotten until I started preparing this talk: if you have a ‘javascript:’ URL which returns a string when executed, that string will be used as the data. This trick was most prominently used in Wolfenstein 5K (long before the wider world caught on to the joys of Javascript size coding contests…), which constructed its display as an XBM image, an obscure text-based format. Before canvas came along, I spent many happy hours trying to replicate that trick with GIF images, discovering along the way that Internet Explorer didn’t like strings containing zero bytes, which sent me down the garden path of constructing valid GIFs containing no zeros. Ah, happy days. In short, I don’t even know if this works at all with <audio>, and even if it does, it’s almost certainly as much of a dead end as it was back in 2004…

One project of mine where I really should have seen the value of generating the audio up-front was Fake Plastic Cubes, a demo I wrote this summer to play around with the size reduction tricks I’d seen coming out of the 10K Apart and JS1k contests, and to try and come up with something audiovisual in as small a size as possible. On the audio side, that meant ditching samples entirely, and doing the synthesis from first principles, building the sound up from plain sine waves – but in a classic case of project management fail, I spent a week building a really wonderful synthesiser framework and rushed everything else at the last minute, meaning that I had no chance to actually make something nice on top of it. As a result, it’s totally unpolished, and the animation keeps stuttering for a split second while it generates the next chunk of audio. It’s only a tiny fraction of the available processor time, but it’s enough to be very, very noticeable. I really should have just generated the entire audio track on startup and then kicked off the visuals – but there was no time for that, or to play around with web workers which would seem to be another potential way to generate audio as a background process…

I also didn’t have time to compose a decent soundtrack, or experiment with the synth enough to come up with interesting sounds, or implement a vaguely sensible way to enter musical notes (as a dodgy workaround, I remapped the names of the notes in the scale to their positions on a QWERTY keyboard and prodded out a melody from those). Fortunately, I didn’t have to let a good routine go to waste: a week or so back, I encountered Sergi Mansilla’s jsmidi project, which provides an easy way to create standard MIDI files from Javascript. However, it turns out that MIDI support in browsers has more or less stagnated – while wave audio goes from strength to strength, MIDI is still stuck in the world of OS-specific plugins – so there was a clear opportunity for some Javascript synthesiser love there. And so I’ve come up with jasmid, a JS library for reading MIDI files and playing them back through its own audio synthesis engine.

A MIDI file consists of a simple header, followed by a list of tracks – each of which is a list of timestamped events, which are usually note on/off events but could be a tempo change, change of instrument or various other things. The timestamps are actually a bit weird: you’d expect them to be given in something like microseconds, but they’re actually expressed as a number of ‘ticks’, where the MIDI file specifies a particular number of ticks per beat, and the tempo of the song is given in beats per second, which can change over time just to add further confusion. Ultimately it probably does make sense, because it means you can accurately use any rational number (within reason) as a tempo, and that’s handy for professional MIDI equipment that has to keep exact time for extended periods – it’s just an initial hurdle that you have to get over. Once you’ve got that in place, a MIDI synthesiser boils down to a set of generator functions that can emit audio waves for as long as you tell them to, and a main loop which picks events off the queue, running the generators until it’s time to process the next event.

For this first release, the generated sounds are not particularly interesting – just plain sine waves with a bit of attack/decay volume control applied – but now that we’ve got the initial framework in place it should be relatively straightforward to add more diverse sounds, and the synth engine should hopefully be flexible enough to support effects like harmonics and reverb.

Finally, as a glimpse of what’s in store for in-browser audio creation in the future, keep an eye on the Mozilla Rainbow project, which provides APIs for capturing audio and video from microphones / webcams. For the last few years I’ve been taking part in February Album Writing Month, a song writing community where collaborations over the internet play a major part – perhaps it won’t be too long until we’re doing that over a Google-Docs-style online equivalent of Audacity / GarageBand…?

It was internally nagging me all summer that I ought to release something at Sundown, but apart from some brief excitement around a brainwave I had involving three iPhones, Javascript and some cardboard (which sadly didn’t work out in practice), it didn’t really amount to much. Then Evoke happened, and inspired me to decide that, in the words of Haujobb’s invitation, I should make a demo.

Or, to be precise, a Javascript 64K intro. Unfortunately, there was only one week to Sundown by that point, and in a classic case of demoscene project management fail, I spent most of that week building an audio framework, leaving about 24 hours to write the actual demo. The end result is 9K of rather-flaky-performing code, hastily improvised plinky ambient music, and dreadful coder art (except to the extent that I’ve ripped it off from Fairlight demos).

• Fake Plastic Cubes – online version
• Fake Plastic Cubes – download (10Kb)
• Fake Plastic Cubes on Pouet

Still, even if the execution this time didn’t work out, I think it’s been a worthwhile exercise in bringing pieces together. Jacob Seidelin’s PNG compression hack (where JS code is stored in a PNG image to take advantage of the compression, then unpacked on a canvas using getImageData) has created a bit of a buzz in the JS development world, but this is the first time it’s been used in an actual demoscene production (which is surprising, given how the demoscene is the spiritual home of size-coding hacks). Ben Firshman’s JSNES has been dynamically generating audio for some time now, ardently chasing the moving target that is Mozilla’s Audio Data API (with a trusty Flash snippet as a fallback), and Mathieu ‘p01′ Henri was experimenting with softsynths long before then. Not even my own code is safe from this cherry-picking exercise of doom – the 3D routines are a mishmash of Gallions Reach / Canvastastic (for the lighting model) and Antisocial (for the full scene / movable camera handling). Finally, node.js makes a cameo appearance, because having an actual web server on hand makes development go a lot smoother.

Put them all together and you have the ingredients for a delicious 64K Intro cake. This time it came out a bit half-baked, but I’m passing on the recipe in the hope that someone else can make it work:

• Fake Plastic Cubes source code / framework, on Github

So far it only implements a subset of the possible sample effects, and it demands a very fast Javascript engine – luckily all the new breed of browsers are pretty competitive at that now. Even so, unless your CPU is an absolute behemoth, it’ll probably struggle to keep up – the audio output is fixed at 44100Hz, and that’s rather a lot of numbers for Javascript to crunch, especially when the MOD file gets up to 16 or more channels. Which, amusingly enough, is exactly the situation we had back when we were using Gravis Ultrasounds on 386es. Hurrah for progress!

Update 2010-06-08: Oops. In the process of testing how Safari 5 shapes up, I discovered a rather silly oversight: the audio buffering routine was set up to never use more than 10% of CPU. Now that I’ve fixed it, it turns out that Chrome and Safari (at least) have no trouble at all playing Jugi’s Dope theme in its 28-channel glory. (However, taking the brakes off the buffering does mean that we can’t reliably pause the audio any more. A small price to pay, I think you’ll agree.)

Incidentally, a couple of people have asked about the identity of the singer in the Outline presentation. Apparently, while that clip is what we sneeringly refer to as an “internet phenomenon”, it’s not quite reached 100% saturation, so: it is Edward Anatolevich Hill, with a Russian TV performance of the song “I am very glad, because I’m finally back home”, or as it’s becoming increasingly better known, Trololololo.

The full description, and a whole bunch of downloads, is on the DivIDEo project website.

This makes it a good excuse for some experimentation with generative music. The secret is in the scale – it’s equivalent to playing only the black notes on a piano, and presumably has roots in oriental music (I previously rediscovered it while working on Haiku). To make it into something like a proper demo, rather than just a throwaway routine, I added a bit of subtle progression Cyberpunks Unity style, so it drifts in and out of randomness as the graphical effects change. It even has a proper ending…

In recent months Yerzmyey has been pushing for the revival of the 16K Speccy as a platform, so I’m pleased to announce that this demo is – so we believe – the third ever demo to run on it.

• Download Spectrumori-on (TAP, 4Kb)
• Spectrumori-on on Pouet

• Download Ode To Claire
• Ode To Claire on Pouet

On the musical front, Snakebite is a chiptune with a middle-eastern vibe, modelled after every Turkish Eurovision entry ever. It got third place in the competition, and originally they weren’t going to give out a third prize, but they had some spare food left over on the Saturday night, so I won a jar of sausages. Best. Prize. Ever.

Download gasman_-_snakebite.mp3

• Download Snakebite – MP3 (2.5Mb)
• Download Snakebite – STC (5.1Kb)

Visit the Antisocial microsite…

With my characteristic lack of organisation, I found myself with two weeks to go to the Sundown party, having promised a demo release, and with nothing specific in the pipeline. So, I decided to take a chance and run with an idea that had been sitting on top of my “demos to write when I have more free time than I do right now” pile for the best part of a year. I had it all planned out in my head, right down to the soundtrack: a mysterious track from an unlabelled CD I picked up at a ZX Spectrum Orchestra gig in 2005 (which turned out to be Round, from their Clive Live^3 EP). A quick bit of permission-getting later, and I was at the point of no return.

I knew it would be an ambitious job, and a bit of a leap artistically and technically from my usual stuff. I pencilled in a rough project plan in my diary. I drew up storyboards. I read up on the maths that was too nasty to contemplate on previous projects. And shockingly enough, I actually enjoyed all of the above.

As it happens, browser technology (as far as the <canvas> element goes at least) has not moved on one jot in the last two years, so I was able to dust off the Canvastastic codebase and found it still pleasantly usable and not too affected by code rot. I gave it a slightly more OpenGL-ish API (within the limitations of my “someone at the pub described it to me once” knowledge of OpenGL) and patched up the more glaring omissions (like Z-plane clipping, so that you can have polygons going behind the camera. Proper frustum clipping would have been a better idea, so that I didn’t end up with it trying to plot 20000×40000 pixel triangles and sending Windows into a stroboscopic flashing fit and having to hack up a fix after the party. Macs are fine with it…).

The demo code was only half the job though; to handle the camera paths and synchronisation and the million other details where hard-coding wouldn’t cut it this time, I joined the big league of the demoscene by building a demo tool (still all in Javascript) that probably only I can understand. (It’s included in the final release, so have a play. I dare you.) As I didn’t have any meaningful experience in 3dMAX, or Flash, or Werkkzeug, or Quartz Composer, or any of the other things I really ought to have been using as reference points, it was a grand exercise in Making It Up As I Went Along. I’d almost forgotten how much fun it is to code that way, but naturally a fair few bad decisions came out of that as well. Firstly, it turns out that organising things around a timeline interface doesn’t really fit all that well; it means that every object and event is treated as independent of everything else, so things get a bit clunky when they have to share resources (such as lots of camera shots of the same scene). Looks like you can’t beat the good old boxes-and-arrows-all-over-the-place approach.

Secondly, and what probably comes as no surprise to anyone but me – Javascript is a bit horrible for building demo tools in. The demo itself, no problem – but for the user interface widgets I found myself constantly wishing for nice, sensible class-based inheritance. Yep, I know the language boffins will say that prototype-based OOP is more powerful, but I guess I’ve just had my mind addled by programming in the real world. I know of a few attempts to graft class-like behaviour onto Javascript, and that should probably be at the heart of any attempted rewrite of this. Alternatively, there’s a growing-but-not-quite-there-yet buzz around alternative scripting languages in the browser (just like there’s a buzz in the opposite direction for server-side Javascript), so perhaps it wouldn’t be out of the question to have a browser demo tool written in Ruby or Python. Or have the browser environment embedded in a ruby/python desktop app – at which point, why stop at browser demos? Could it be designed as a more general tool, where the browser is just one of many platforms that can be swapped in? It’s tempting. Onward and upward!

Download matt_westcott_-_everything_is_relative.mp3
This started out as an instrumental track laid down at Shucon 2008 on TDM’s GarageBand / MIDI setup, which came back to bite me as a nasty bit of vendor lock-in. (I figured that since GarageBand took MIDI input and stored it as MIDI-like note events, I’d be able to export it to a .mid file, right? Silly me.) Luckily I managed to salvage / re-record enough of it to work on it some more and develop it into a proper song. Spurred on by some particularly eclectic music competitions at Assembly, I decided to try my luck at entering it at Evoke, just to see what would happen when it was thrown in against a whole load of D+B and trance tracks. Not surprisingly, it failed to qualify. But having done the rounds of more or less the entire summer demo party season, it found a home at Sundown 2008, where it got 4th place. Score!

The lyrics were actually sparked by the train journey back from Shucon – at the seat in front of me, I saw that someone had drawn some initials in a heart on the window. This made me think “eww, that’s a bit tacky. Oh, hang on – whoever did that drew it on the outside of the window but did it in mirror writing so his girlfriend on the train could read it. Aww, that’s like the most romantic thing ever!”

Edgware Road

Download matt_westcott_-_edgware_road.mp3
A slightly more obviously train-related song, written to immortalise that enigma of the London Underground where time stands still, and add to the repertoire of songs about tube stations. Lyrics were mostly written on the Eurostar (hence the namecheck in the bridge) and the recording was done a-cappella stylee in the cabin of a sleeper train on the way back from International Vodka Party. Naturally, this was a horrible painstaking process of waiting for the moments when the train wasn’t making an absolute racket, but it had to be done for posterity. How many other songs have been written and recorded entirely on public transport, eh?

Cabbage Soup For The Soul

Download matt_westcott_-_cabbage_soup_for_the_soul.mp3
Written for Hoopshank as part of intense negotiations (not really) over contributing to another as yet unannounced musical project. He demanded songs of cabbage… I answered the call. I added a self-imposed constraint that the song had to have a mostly-serious message, so I came up with the idea of cabbage soup for the soul, as being something like Chicken Soup for the Soul but not as pleasant, and better for you. And suitable for vegans. And with that, the song just wrote itself. Or, more accurately, was written on my behalf by my alter ego, fictional Scottish indie band Glencoe Horse.

At The River (slight return)

Download matt_westcott_-_at_the_river_slight_return.mp3
OK, scraping the barrel a bit here. But you can’t really blame me for having a sudden bout of obsessive-compulsive disorder on realising that the lyrics to At The River by Groove Armada consist entirely of a half-sentence that trails off unsettlingly without completing its train of thought. “If you’re fond of sand dunes and salty air, quaint little villages here and there,” – then… what exactly? Clearly, this had to be fixed. So I did.

(All songs downloadable from the not-very-pretty music.matt.west.co.tt – lyrics available from my 50/90 profile)