What can Theora do that VP3 couldn do?
The major change from VP3 to Theora is architectural. VP3, like most codecs of today, makes certain assumptions about the nature of the material it compresses. These assumptions take the form of fixed sets of numeric values, such as quantization matrices, which control how different frequency components of the signal are handled, and token frequency tables, which control the efficiency of post-transform lossless coding. In Theora, we have leveraged the intrinsic flexibility of the Ogg multimedia framework to allow the encoder to modify these values appropriately for the material. This simple, powerful approach has already been proven effective in Vorbis, and will allow for a longer cycle of encoder optimization without requiring client-side updates.
