how to handle OpenGOPs warning from DVDLab-Pro

[Hiddengibbon]

I use PGCDemux to Demux .m2v from my DVD.

But after I import .m2v to DVD Lab Pro, It's warn about Open GOPS and said that Chapter point may not accurate.

How to handle this situation in order to accurate Chapter Point ?

Thanks for every reply.

[guns1inger]

You have two choices

1. Close the GOPs when encoding - see your encoder manual for details

2. Turn off the warning in project properties (version 1.6 and later) so it doesn't bug you.

Chapter points are only guaranteed I-frame accurate anyway. If you frameindex you can set them to the nearest I-frame, then give frame offsets to get better accuracy.

However, if you are really aiming for that level of professionalism, you will be using an encoder that will allow you to close GOPs and set I-frames according to your chapter placement during encoding (this means planning your chapter stops ahead of encoding) so this isn't an issue anyway.

I encode with open GOPs, I frame index prior to setting chapters, and I have no issues.

[adam]

Its just a guess but if all you did was demux the stream and reimport it, and you are taking the chapter points off the DVD, than the I frames should already be placed at the set chapter points. So just ignore the warning.

To be sure you can check the chapter points of the authored DVD and compare it against the original chapter points.

[guns1inger]

DVD Decrypter can also produce a list of chapter points in DLP format from the original disc (sorry - missed the bit about coming from an original)

[Hiddengibbon]

DVD Decrypter can also produce a list of chapter points in DLP format from the original disc (sorry - missed the bit about coming from an original)

I get Celltimes.txt from DVD Decrypter and import it to DVD Lab Pro.

But almost of the chapter got lag for 1-2 frame.

That's my problem

[guns1inger]

Have you frameindexed ?

[adam]

Celltimes gives you cells, not chapters. For instance, there may be several cells within each chapter. If you are authoring with DVD Lab then in DVD Decryptor you should use the "chapter information DVD Lab option."

In the heirarchy of DVD authoring it goes: Title, Programs, then cells. It is the programs that correspond to the chapters.