[mythtv] Keyframe adjust table (posibel bug(s))

Geoffrey Hausheer ou401cru02 at sneakemail.com
Sun Jan 4 21:22:02 EST 2004


On Sun, 4 Jan 2004 23:13:11 +0100, "Torbjörn Jansson" said:
> So how shoud this be fixed?

Well, I have just committed fixes for all the bugs you mentioned.
Specifically, the seek-table should correctly mark 'SV' frames again,
and the KFA table will function properly.

This won't fix the files that are already broken, although it would be
pretty easy to rebuild the seek table.  

I am unsure why you are having an issue though.  The seektables in
transcoded files do point at a valid frame.  It just may not be a sV
frame (specifically, it may be an 'A' or 'R' frame).  But you are
gauranteed that there is an SV frame between the seektable position and
the next 'V' frame.

You do need to account for the kfa stuff, but if you look at
nuppeldecoder now, it should be obvious how to do so (I changed the
handling to be more intuitive)

> Shoud I just ignore the seektable and kfa table if
> keyframeadjust_offset>0 ?
You can do this if you like, but don't assume that they come every
keyframedist.


> I have a thread that is started when the seektable is missing and not
> streaming from mythbackend directly that takes care of scanning the file
> for
> video sync frames and building a new seektable internaly.
> 
You could do that, but I don't think it should be necessary

> The problem is that this broken seektable messes up the timestamp
> calculations, so with my sample file (Antz) if I seek to a position near
> the
> end of the file, I will have to wait 8-9 minutes afte a seek before the
> video starts.
I'm not sure why.  As I said above, while it wasn't right, it wasn't THAT
wrong.

.Geoff


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