Am Thursday 24 August 2006 10:34 schrieb anopheles:
> Hi guys

Hello Brian.

> I've been using a script to help me process dvbcut files -
> it realigns the cut positions within the MPG file saved from dvbcut.
>
> This allows me to
> a) test the edit points in the final MPG
> b) reconstruct the chapter timestamps if I originally forgot to save them.
>
> If you are interested you can find this script here:
> http://www.clr.eclipse.co.uk/dvbcut/recut/
> (requires python)

I had a look at your script. I did not read the whole source code, but looking 
at your comments there might be one error inside.

From your code:
>     read a dvbcut control file from given file
>     and recalculate the cut points presuming that the control file
>     has already been applied.
>     Write new version of cutfile to cut_filename.new
>
>         start 100
>         end   200
>         start 300
>         end   400
>     becomes
>         start 0
>         end   99
>         start 99
>         end   198

The calculation is not correct. The new marks should become 0,100,100,200. 
Just see that for corresponding start and stop marks, the quantity stop-start 
(which is the number of pictures for that cut) should stay constant. So from 
the original values 200-100 must be equal to 100-0. (It is not equal to 
99-0.)

And then... sorry to say, but you would have a much easier life if you made 
use of the Python XML module. (See the attached script.)

> However, I also note that the final STOP mark is always a few frames (i.e.
> more than one) beyond the end of the MPG file, as though dvbcut has stopped
> short of the desired position.
>
> Can anyone explain this? Is this just the down to the old discussion of
> whether the STOP mark is in or out of the cut?

I guess the treatment of the DVCBUT file by the script is correct (apart from 
that off-by-one thing). I would guess the point is, that when re-reading the 
mpg file into DVCBUT, it doesn't read it in full. When I remember correctly, 
the indexer of DVBCUT stops at an I-Frame and ignores the last P/B-Frames in 
the file. This is, I must admit, an unneccessary limitation which probably 
originates from my usual usage of DVBCUT, using huge bulk TS-Files as source. 
There you don't mind missing a few frames in the end... a future improved 
implementation should not have this limitation.

Bye,
 Sven.

-- 
Sven Over
Stephanienstr. 9
76133 Karlsruhe
GERMANY

Telefon: 0721-9204199

http://www.svenover.de/

Attachment: recut.py
Description: application/python

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