Hi folks: I realise this is off topic, but I know that there are at least some interested people on this list, and there are small sections that are relevant. Feel free to skip this message if you're not interested. As some of you will know, I have a great interest in the new open-source audio format that is called ogg vorbis. Things have been happening a bit lately, so I thought I'd bring those who are interested up to speed on where things are at and where they are going. We're getting to some of the exciting stuff now, so if you're at all interested, read on. For those who don't know about vorbis, briefly vorbis is a freely available and usable audio format which is being developed in the opensource community, with the intention of escaping the patent fees and other red tape associated with MP3 and its competitors. Feel free to drop me a line with any questions. OGG Vorbis 1.0beta4 Vorbis 1.0beta4 is due out shortly. The problem is that vorbis.com has been caught up in a rangle between 2 internet companies. The situation is being resolved, and has been at any day now status for 2 weeks. Once it is back up, beta4 will be released. Prebeta4 files have been available in CVS for several weeks, but the developers have taken advantage of the vorbis.com outage to continue development. Yesterday however, Monty announced a freeze for beta4 so that the bugs can be ironed out. There's not a staggering amount of new stuff in beta4, as development has once again proved slower than anticipated. Beta3 introduced some pretty serious encoder bugs which have now been resolved. More bugs have been squashed in beta4, as well as some pretty dramatic speed increases (you can now encode in realtime or better on some systems and this will continue to improve). There are also now better algorythms for VBR bitrate selection. There's not been much chatter on the development list lately, so the odd feature or 2 may have been added in the last couple of weeks. Guess we'll just have to wait and see. Vorbis 1.0beta4 is not the release candidate for 1.0 that was hoped for. 2 major features that need to be included are joint stereo and bit pealing, a technique where you can get higher sampling rates at lower data rates by simply discarding the right data bits. Monty, the core developer for the vorbis libraries doesn't want to rush any of this stuff, so it could be a little while yet. In the meantime, a lot has been going on in other areas. Developers have been working hard to get vorbis to compile on numerous platforms and compilers. It has most recently been patched to compile on Apple's soon to be released macos X (aka Darwin). compatibility is probably going to be a big thing going for vorbis when it's ready for prime time. Icecast 2.0 now at prealpha Icecast is being completely rewritten for version 2.0. 2.0 will stream vorbis instead of mp3. For the truly brave, there is already some prealpha C code to play with. Unfortunately, icecast.org is caught up in the same rangle, so it is currently also offline. The icecast team are hoping for icecast 2.0 to be ready at the same time as vorbis 1.0 is released. The ogg vorbis format allows for some pretty exciting possibilities when it comes to live streaming. Firstly, because you can (or will be able to) perform bit peeling, it becomes trivial to send out a vorbis stream at a lower data rate than the one supplied to it. The implications are quite obvious - a source audio stream could be provided at 128kbps and the server could determine the correct datarate for a client and send it out at that rate. People on cable or DSL could get the full 128kbps or near to that, whilst lower bandwidth users could hear it at a lower rate, all with one server and all from the one source. Another thing that looks promising is the fact that the ogg stream and icecast 2.0 are both designed to handle chained vorbis streams. This means that unlike mp3, vorbis players will be able to cope with one vorbis stream following another one. The vorbis specification calls for all the appropriate decoder information to be sent out at the top of the stream, so a decoder will be able to cope with differing bit rates or sampling rates, as the information needed to cope with this will be automatically sent out as part of the vorbis stream. This will be pretty useful for projects like ACB radio interactive which suffers from the stream being dropped between shows, partly for the very reason that MP3 does not deal well with situations like this. A number of media players already support vorbis, and will be made to support icecast 2.0 before it comes out. There are vorbis plugins for winamp, sonique freeamp and xmms, plus stand-alone vorbis players doing the rounds already. The list will likely grow before vorbis 1.0 is released. Realplayer plugin now available The latest program to have vorbis support is realplayer from realnetworks. The plugin was written by the vorbis developers, so it's not yet a standard part of realplayer. Hopefully it will be one day, but for now I presume it will be available for download soon, perhaps even with the 1.0beta4 release. For those who have the realplayer SDK, you can get the plugin from vorbis CVS and compile it. For info about vorbis CVS, see http://www.xiph.org/ogg/vorbis/ Oddsock DSP plugin for winamp now supports vorbis Oddsock recently made a plugin to replicate the shoutcast DSP plugin using lame. Beta7 is now out and supports the vorbis format in addition to MP3. At present, there isn't much use for such a beast as there are no servers to stream to, but it is ready and waiting for icecast 2.0 and any others that may appear. They've also made some improvements to the mp3 stuff too. If you're into checking out winamp plugins, visit http://www.oddsock.org/tools/dsp_oddcast/ I've not heard of any work to make any of the icecast streming tools (e.g. liveice or isis) vorbis compliant, but I wouldn't be surprised to see it happening soon. Well, that's about all for now. Feel free to drop me a line if you have any further queries about vorbis or any of the related projects - I keep on top of the relevant mailing lists. Geoff.
