[Live-devel] Urgent help needed!

[Morgan Tørvolt]

On 07/02/07, Ross Finlayson <finlayson at live555.com> wrote:
> >If you indeed do implement this, remember to do time adjusting also in
> >the index-file version, as the double precision is not good enough.
> >Gave us problems every half hour or so.
>
> Can you explain some more what you mean by this?

Sorry, poorly explained. What TransportStreamFramer does now is to try
to adjust the duration partly based on the system time of the server
using the TIME_ADJSUTMENT_FACTOR. You will still need to do that when
using index file even though the PCR should be accurate enough. We did
not do this at first, thinking the PCR time was more than sufficient.
The problem is that the double variable we used for the PCR value is
not accurate enough ( I did not believe it at first eighter ). I guess
that with the PCR timestamp accuracy on its 33bits, the least
significant digits are not exact enough when divided by
numberOfPackets, and .001us (or whatever the error is, I don't
remember anymore, was a year ago) error per packet did obviously add
up to a whole lot for some odd reason =)

> That sounds like it could be something worthwhile to add in the
> future.  (The index file already records the locations of GOP
> headers, so it should be possible to do this without modifying the
> index file format.)  It's not high-priority however...

Of course. Maybe I will try adding it if I ever get the time. What we
have now is neighter very nicely coded nor compliant with many
standards I believe. continuity_counter and other things are
completely disregarded because the STBs did not care.


Regards
Morgan Torvolt