On Wed, Sep 22, 2004 at 12:50:52AM +0100, Karl Heyes wrote: > On Tue, 2004-09-21 at 22:18, Joern Nettingsmeier wrote: > > > Other than ices and icecast, do both the icecast box and the ices box > > > need all of the svn packages you list above? > > the icecast box does not need the *-tools. (nor does ices strictly > > speaking, but they are nice to have). i described a "bleeding edge" > > best-of-xiph.org setup. if you don't want to play with video or > > very-low-bandwidth speech streaming, you can omit the speex and > > theora packages as well as flac. ices/icecast check for them at > > compile time - i wanted all bells and whistles, but if the libs are > > not present, those features will be left out with no problems. > If you are taking from svn, then you need the autoconf etc tools, but if > you are using tarballs then the configure script will be already built > so it won't be needed in that case. > > you may even get away with using your distro's libvorbis, although i > > think ices-kh does require ogg2 and won't compile with plain old ogg. > no, ogg2 is not required, and AFAIK the vorbis codec may not be working > with it just yet. Thanks Karl. > > when you do this, consider that under ideal circumstances, re-ogging > > a pcm stream that has been ogg-encoded before will not add new > > encoding artifacts, unless you reduce the bitrate. > I don't think you can state that in general, as the second encoding will > operate on different pcm input. Given the same encoder settings it's > unlikely to loose much. My composition-thing will decode previously encoded portions of the stream, apply manipulations (time-stretch/compress & possible reversing) and then mix them together with others similarly manipulated. Additionally, the recording portion of the system will choose a vorbis quality at random from the range of worst-best for each recording. So, there will be some effect from the encode-decode cycles. But, even if that effect is minimal the system still messes with time scale stretch/compress, reversal of audio data and mixing streams together at random. Something interesting, at least to me, will come of it. The ogg vorbis part at least provides a larger pool of previous recordings to feed back into the system by virtue of saving some disk space. -Eric Rz.
