Re: Fixing GOP Length???
Jan Panteltje
wrote in <b4gd21toa7qnv1vrv...@4ax.com>:
>
>I can't seem to find a straight answer on this. Is it possible to
>change the GOP length of an MPEG1/2 without re-encoding the file??
No
>Some software programs have a "fix GOP" option that doesn't seem to
>have anything to do with length.
Yep, sometimes it can drop the entire defective GOP too.
> How do people deal with incorrect
>GOP lengths, and what's the "so what" of this...
Re-encode.
> Do these types of
>files not play properly in standalone DVD players? Thanks.
All PC based programs should play it.
Many standalone players will play the DVD, I have 2 here that do.
Cannot really see a problem, but it is not spec, and if you want to sell
commercially and people send the DVDs back because it sucks on their player,
then you have a problem.
Re-encoding does not really have to create a lot of degradation in quality.
My view anyway.
Ken Maltby
<no...@nospam.123> wrote in message
news:b4gd21toa7qnv1vrv...@4ax.com...
>
> I can't seem to find a straight answer on this. Is it possible to
> change the GOP length of an MPEG1/2 without re-encoding the file??
> GOP lengths, and what's the "so what" of this... Do these types of
> files not play properly in standalone DVD players? Thanks.
What do you mean by "incorrect GOP lengths"? Do you mean
the DVD standard, more than 18 frames for NTSC or 15 for
PAL? Do you have MPEG with oversized GOP that won't
play in your stand alone player? ( The standalone players are
much less sensitive to that than the PC players.)
There is no problem having a mix GOPs of different sizes.
There is no problem if they are smaller than the standard, all the
way down to the "I Frame" only variety.
So what problem are you having that you feel is related to
the length of your GOP?
Luck;
Ken
Ken Maltby
<no...@nowhere.123> wrote in message
news:2qse2114soiepk49d...@4ax.com...
> some videos give me a warning in TDA that the GOP length is too long.
> I wanted to avoid re-encoding because I didn't want to reduce quality.
> Now that I think about it though, I wonder if I could use a program
> like DVD shrink to create new VOBs with the original VOBs that have
> excessive length? I need to try this..
>
Actually TDA is one of the few Author programs that can work with
Oversized GOP, just ignore the warning message.
The TMPGEnc 3.0 Express Encoder has an extended MPEG2 format:
"XDVDs exceed the GOP limit of the DVD standard and is capable of
storing more than 60 frames in 1 GOP without ruining the clip. XDVD
pushes the MPEG standard to its limit. DVD player software tend to
emphasize speed than video quality. For this reason XDVDs can not
show its true potential. It is strongly advised to play XDVDs on a
consumer DVD player.
When authoring XDVDs with TMPGEnc DVD Author 1.5, a message
"The video GOP is too long" will show up but you may ignore this and
continue to author."
Luck;
Ken