(This is packed in the same way the rest of Ogg data is packed; LSb
of LSB first. Note that the 'position' data specifies a 'sample'
number (eg, in a CD quality sample is four octets, 16 bits for left
and 16 bits for right; in video it would likely be the frame number.
It is up to the specific codec in use to define the semantic meaning
of the granule position value). The position specified is the total
samples encoded after including all packets finished on this page
(packets begun on this page but continu