App to change BFF/TFF flag in a mpeg2 file
 

Hi,

I tried to encode my last KDVD as interlaced, but I badly let the BFF/TFF flag in HC016 to BFF, when the file is TFF: I discover it during the playback, on the TV ! .

The file is really TFF (checked with avisynth script and dgbob), and I discover an app (projectX) that let me change this flag.

I'm burning the DVD to check the result, but I'm sure the playback will be ok.

Just in case it could help someone...

Fabrice

Restream can do that also, if I'm not wrong.

Hi,

I totally forget this nice tools.
I've checked, and you'reright: it allows you to see and change tff field value.

Thanks,
Fabrice

Can ProjectX do it without having to save to a new file? IIRC ReStream needs to save to a new file which can sometimes take a long time.

Hi,

ProjetX demux the file, so it take some time (and a bit more because it's a java application).
ProjetX is thinked to work with TS files, so it's logical to demux the input file...

Salu2
Fabrice

What about DVDPatcher or AVestensione ?

DVDPatcher can't change these flags. I don't know the other tool.

Pulldown.exe also changes the field order.

http://www.inwards.com/inwards/?id=36

Re: App to change BFF/TFF flag in a mpeg2 file
 

Btw, can someone explain what these flags are and what do they do, for the learning of ppl like me :)

This is for interlaced streams. In such streams, each frame is encoded in two "half-frames", each containing the odd or even lines.

To display a frame you have to take two "half-frames", interlace their lines, and display the resulting full frames.

The flag tells if the odd lines are seen in the first half frame or the second.

I hope I'm not wrong as I rarely use interlaced streams.

And if the field order is set incorrectly (DVDs are mostly top field first), you get jerky motion. It looks as if everything went back and forth so you can't miss it.

Hi,

Believe me, you can't miss it! (well, my son watch all the movie, and don't complain about it! :-) )

Salu2
Fabrice

It looks like a "stroboscopic" effect. Very annoying.