Hacking VLC Media Player
So, I’m at a Hothouse at BT’s Adastral Park campus, doing some work involving remote control of the VideoLan Media Player (aka VLC). VLC is an open source media player with support for a wide range of codecs, and with some fairly sophisticated features like stranscoding, streaming, and remote control via the integrated HTTP server. To use the latter, you need to start VLC with a special switch from the command line:
"/Applications/VLC.app/Contents/MacOS/VLC" --extraintf=http
Once you’ve done that, you’ll be able to interact with the player through this web interface:
http://localhost:8080/index.html
The HTTP interface also permits VLC to be controlled with simple HTTP requests. For example:
curl -g "http://localhost:8080/requests/status.xml?command=pl_stop"
curl -g "http://localhost:8080/requests/status.xml?command=pl_play"
The HTTP interface also serves static web pages, and includes a fairly rich-but-unusual macro/templating system for creating dynamic pages like the remote control interface above.
UPDATE: More useful URIs
/requests/playlist.xml - Retrieve current playlist in XML format /requests/status.xml?command=pl_empty - Clear current playlist /requests/status.xml?command=in_enqueue&input=<uri> - Add URI to playlist (example) /requests/status.xml?command=in_play&input=<uri> - Add URI to playlist and start playing
links for 2009-07-06
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Harry Metcalfe's rather nice and polished PDF parser… might be handy for TiddlyDocs
links for 2009-07-02
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Interesting essay about UnaMesa, the custodians of TiddlyWiki (amongst other things), from it's founder Greg Wolff
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TiddlyWiki integrated into SecondLife
links for 2009-06-17
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Slick jQuery animation demos. "Only a few years ago, when you think about animation on the internet, the first tool that come to mind is Flash. This is not the case today"
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Cheerful thing to read on a sunny morning: "There is a growing feeling in the City that BT may be turning the corner after a difficult time"
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Chris Dent and FND deftly demonstrate the wonders of TiddlyWeb with a plugin to render Eric Meyer's S5 presentations – all done in an evening, too
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Terrific article about Osmosoft from Telco2.0
links for 2009-06-10
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Summary of nine different editions built from the TiddlyWiki core, mostly around Getting Things Done
links for 2009-05-27
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Interesting shared whiteboard type thing, very nicely implemented in HTML+CSS+JS
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Lovingly produced guide to TiddlyWiki and MPTW
links for 2009-05-22
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A TiddlyWiki vertical edition for writers
links for 2009-04-30
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Thirty-seven year old news, but fairly mind-boggling: it seems that if the conditions are right, nuclear reactors can form in nature, and have at least once. Gosh
links for 2009-04-29
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Visualising tabular data (via hepwori)
Presenting TiddlyWiki to the W3C
Today, my colleague Paul Downey has made an impressive contribution to Osmosoft’s mission to explain by preparing a paper about TiddlyWiki for submission to the W3C Workshop on Security for Access to Device APIs from the Web. It gives an overview of TiddlyWiki for technical audiences that already know and understand the mainstream web and its underlying technologies.
Paul’s paper can be found here:
http://osmosoft.com/~psd/TiddlyWikiDeviceAccess/
I’m loving it in lots of different ways. It’s a really solid example of what I call a “manifesto-style TiddlyWiki”, a tightly knit mesh of content that together communicates a system of belief. I like his tone, too, nicely sober and authoritative.
The challenge that Paul has taken on isn’t to be under-estimated. I’ve had the chance to talk about TiddlyWiki to many different audiences around the world, but the most unexpected reaction I encounter is from people in that same, technical audience and it is, bizarrely, outright disbelief. Picking it up in the middle of a demo, the conversation goes something like this:
Jeremy: Here I am clicking the ’save changes’ button, and now watch as I refresh the page in the browser, and you can see that the changes that I made have been persisted to disc
Expert: Right, that’s very interesting. What serverside technology are you using? I bet it’s Java, isn’t it?
Jeremy: No, actually, as I said at the beginning, TiddlyWiki is a standalone HTML file, with the application logic written in JavaScript
Expert: Ah, I see, so you’re using something like Rhino to run the JavaScript on the server?
Jeremy: No, not at all. TiddlyWiki runs entirely on the client browser, and takes advantage of special privileges accorded to HTML files loaded from “file://” URIs to be able to save itself directly to disc
Expert: That’s neat. So do you use Google Gears to handle going offline?
Jeremy: Sigh, no, not quite.
And so it goes, on and on. It sounds ridiculous, but it’s happened too many times or me to avoid thinking about it. It’s seems that the idea of a standalone HTML file is sufficiently far away from many people’s experience of the web for it to be invisible to them.
The frustration for me is because it feels as though TiddlyWiki has something important to say about the different things that happen if you let people hack the web without needing server infrastructure. My experience is that you can foster some intense innovation by radically lowering the barriers to the Copy/Modify/Share cycle that is at the heart of community innovation.
