[vorbis-dev] Howto use ogg_page_granulepos for exact playback position?

[rillian]

On Tuesday, April 16, 2002, at 09:33 AM, Tibor Kiss wrote:

> I don't understand the meaning of 'exact granular position of the packet
> data contained at the end of this page'.

Perhaps the version in the ogg framing spec is more clear:

  The  position specified is the total samples encoded after including all
  packets finished on this page (packets begun on this page but
  continuing on to thenext page do not count).  The rationale here is
  that the position specified in the frame header of the last page
  tells how long the PCM data coded by the bitstream is.  A truncated
  stream will still return the proper number of samples that can be
  decoded fully.

<p>> While I feed the encoder and no page boundary were found between two 
> feeding
> cycles (there is no effective encoded output), the ogg_page_granulepos 
> is
> increasing continuously. How I understand ogg_page_granulepos is not the
> right function for me.

So what gets written as the granulepos when the page is flushed is the 
last sample that can be fully decoded using that page. So as packets are 
added to the page buffer, of course this number increased, and indeed 
that's how it's passed in in the packet structure. Thus it tells you how 
many samples have been encoded assuming you flush the page now.

Is that what you were asking?

  -r

<p>--- >8 ----
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