Encoding Hard-Telecined DVD?

[Berz Rejka]

How can I prevent the dvd-rb from adding the original pulldown flags to the mpeg2 video when doing the last rebuild sequence?


A LOT of Asian films are hard-telecined and re-encoding them with dvd-rb is a problem. Precisely, the problem is with the way dvd-rb rebuilds the dvd and inserts the "original" flags to the video.

In the hard-telecined video the extra interlaced NTSC frames are included in the video opposed to the soft-telecined material where the NTSC frames are created by the dvdplayer when played/needed according to the pulldown flags while retaining the a/v sync.

The only sure way I know of to correct the video and "remove" the interlaced frames is to partly deinterlace the video thus leaving the unnecessary (though improved) NTSC frames to the video. The video is still 30fps and in sync with the audio.
But the jerkyness intoduced by the extra frames is still precent.

With hard-telecined 30fps NTSC video dvd-rb seems to change the frame_rate to 23976 and then encode the video to the same framerate, BUT in the rebuilding process it reconstructs the dvd and returns the playing speed to the original 30fps.
I assume that dvd-rb does that by inserting the original flags to the mpeg2 video. No frames are removed.

THOUGH, the hard-telecined video can be "corrected".

The telecined NTSC frames can be removed by using IVTC through avisynth script and later manually adding the 3:2 pulldown flags to the encoded .m2v files (also CCE can insert the pulldown flags when encoding).

First I change the Frame_Rate=23976 to Frame_Rate=29970 in the correct V0x.d2v project file.
Then I insert the IVTC script to the dvd-rb "filter editor" and make sure the encoders (CCE) encoding speed is 23,976fps (rebuilder.ecl). Now the NTSC frames get removed when encoded.

After encoding, the created .m2v video looks perfect without the unnecessary interlaced NTSC frames and plays with the correct speed of 24fps. The picture moving speed is natural, no faster or slower than the original 30fps.
Then I add the 3:2 pulldown flags with pulldown.exe.
Now the video is still 24fps with 3:2 pulldown, but plays 30fps when needed to.

But when I try to rebuild the video, dvd-rb screws up the video playing speed resulting an "out of sync" video and audio. The dvd becomes 30fps opposend to the 24fps with 3:2 pulldown it should be. Changing the "pulldown=" setting in rebuilder.inf does nothing.

I suspect that when the dvd-rb rebuilds the dvd it replaces the manually inserted 3:2 pulldown flags with the original flags and the video playing speed becomes corrupted. Because the framecount decreases when IVTC is applied, changing to the original 30fps framerate makes the video play too fast.


Now I need to now, How can I prevent the dvd-rb from adding the original pulldown flags to the mpeg2 stream? How can I make dvd-rb to correctly rebuild the dvd?


I bet there are alot of people with the same problem. The extra frames take too much space and reduce overall quality of the reencoded dvd. The interlaced frames look terrible and ruin the movie. There have been discussions of this before but nobody has never been able to get this thing to a satisfying conclusion.

Can anyone help with this?

[jdobbs]

I don't mean to be defensive, but what you're saying just isn't correct. Saying DVD-RB "screws up" anything is way off the mark. So is saying it doesn't correctly rebuild it.

It's "screwed up" because you inserted filters that screwed it up... so what you are asking is "Why doesn't DVD-RB unscrew it?"

But, with that said, DVD-RB is designed to make a backup of the original -- exactly as it was -- even if that is hard telecined.

The only way you could currently do an IVTC on a hard telecined source with DVD-RB is by recreating all the .FLG files with the correct sequence of TFF/RFF flags to perform telecining for playback.

It may be possible for me to put a flag into DVD-RB that tells it to ignore the .FLG files and read the M2V as-is -- but you still have a problem. The telecining has to keep going across the segments. The way you've added the flags for pulldown, they would, very probably, have a hiccup at each segment break because the pulldown sequence gets interrupted and restarted.

Actually in most areas hard telecining is pretty much non-existent except in pirated discs or those made from broadcasts, that's why it hasn't been an issue (that and the fact that DVD-RB backs it up fine in their originally authored form). Give me some time to think about it, and maybe I can write a short utility that will redo the .FLG files into a single pulldown stream.

[Berz Rejka]

It's "screwed up" because you inserted filters that screwed it up... so what you are asking is "Why doesn't DVD-RB unscrew it?"

Point taken, I just meant that dvd-rb isn't flexible in that way...
dvd-rb is in no way a "bad" program, it does what it is supposed to do. It just lacks that kind of options and/or documentation that enable us DIYs to thoroughly "tinker" with the different kinds of dvds.

It may be possible for me to put a flag into DVD-RB that tells it to ignore the .FLG files and read the M2V as-is -- but you still have a problem. The telecining has to keep going across the segments.

Would it be possible to include a setting that will force CCE to automaticly create the choosed/correct flags to the mpeg stream? Or will that too hickup at segment breaks?

The way you've added the flags for pulldown, they would, very probably, have a hiccup at each segment break because the pulldown sequence gets interrupted and restarted.

Actuall, I also thought of that, while rebuilding dvd-rb gave some errors about missing frames, but I could not properly test the final "product" because of the increased 30fps video playing speed.

Actually in most areas hard telecining is pretty much non-existent.

Though, I have many imported region 1 and 3 discs, old and new, released by small companies and those are mostly hard-telecined. The hard-telecining is SO annoying (especially when you have big lcd and progressive dvdplayer) that before watching I like to remove it from ruining the viewing experience. The NTSC jitters and jerkyness gives me a headache so I like to watch dvds Film like (24fps).

Give me some time to think about it, and maybe I can write a short utility that will redo the .FLG files into a single pulldown stream.

Very much apreciated, thank you. I think I'm not the only one battling with "unscrewing" these hard-telecined dvds.

[galfwender]

Actually in most areas hard telecining is pretty much non-existent except in pirated discs or those made from broadcasts, that's why it hasn't been an issue (that and the fact that DVD-RB backs it up fine in their originally authored form). Give me some time to think about it, and maybe I can write a short utility that will redo the .FLG files into a single pulldown stream.

Sorry but this isnt the case - Many recent tv dvdsets are hard telecined - Sleeper Cell, What I Like About You, Everybody Loves Raymond, Scrubs.. Some even simply duplicate every fourth frame to convert from 23.976 to 29.97 rather than traditional 3:2 pulldown. I really think DVD-RB needs to be able to address this.

[jdobbs]

Are you positive it is hard telecined? I do a LOT of discs and can only remember one time I've ever actually encountered one that was hard telecined. I would have thought something like "Everybody Loves Raymond" would have been 29.97fps in its original form.

I'll pick up one of the titles you mentioned and do a little analysis. Just to be sure, can you send me one of the .FLG files from a section that is hard telecined so I can look at it? (send to dvd-rb@dvd-rb.com)

[wmansir]

This case is rare nowadays in mainstream releases but I can confirm Scrubs S1 and 2 from that list at least. Also, I know Scrubs and Raymond are unusual for half hour sitcoms because they were shot on film and xfered to video.