Hi, Another newbie question. I'm trying to figure out how to fit vorbis into the Apple AudioCodec API and it asks your codec to be able to answer questions about itself. One I'm not sure about, does vorbis encode a fixed number of frames per packet for any given track? I know it's VBR, but that doesn't necessarily imply variable # of frames per packet. Thanks, -n8 -->>>-- Nathaniel Gray -- Caltech Computer Science ------> >>>-- Mojave Project -- http://mojave.cs.caltech.edu -->
On Mon, Sep 19, 2005 at 10:59:04PM -0700, Nathaniel Gray wrote:> Hi, > > Another newbie question. I'm trying to figure out how to fit vorbis > into the Apple AudioCodec API and it asks your codec to be able to > answer questions about itself. One I'm not sure about, does vorbis > encode a fixed number of frames per packet for any given track? I > know it's VBR, but that doesn't necessarily imply variable # of frames > per packet.Hi, the number isn't fixed, but it is limited to about 4 values within a track (or within a chain to be precise). Craig Duncan posted some source code for determining the number of samples in a packet: http://lists.xiph.org/pipermail/vorbis-dev/2005-April/018029.html Conrad.
On Tuesday 20 September 2005 07:59, Nathaniel Gray wrote:> Hi, > > Another newbie question. I'm trying to figure out how to fit vorbis > into the Apple AudioCodec API and it asks your codec to be able to > answer questions about itself. One I'm not sure about, does vorbis > encode a fixed number of frames per packet for any given track? IIt encodes exactly one frame per packet. Where multiple packets may be stored in one page (ogg). The framessize can be one of two sizes (i.e. number of samples) the sizes are stored in the header> know it's VBR, but that doesn't necessarily imply variable # of frames > per packet.the vbr comes from variable packet sizes> > Thanks, > -n8