CCE doubt: Interlace or Progressive.

[jbalakri]

I am following the "Getting the best out of CCE" guide and I am having a basic doubt regarding CCE video settings for Interlaced or Progresive. When I open the VOB in Bitrateviewer, this is what I get:

Num. of picture read: 24971
Stream type: MPEG-2 MP@ML VBR
Resolution: 720*480
Aspect ratio: 4:3 Generic
Framerate: 29.97
Nom. bitrate: 8230000 Bit/Sec
VBV buffer size: 112
Constrained param. flag: No
Chroma format: 4:2:0
DCT precision: 10
Pic. structure: Frame
Field topfirst: Yes
DCT type: Field
Quantscale: Nonlinear
Scan type: Alternate
Frame type: Interlaced
Notes:

But when I play the video in DVD2AVI, Video type is FILM at a percentage higher then 95%. Also I loaded the d2v file in Gordian Knot and advanced the frames but I could not see any interlaced lines. So I think this movie is progressive. But the Bitrateviewer says otherwise. I have the following questions:

1) Which reading should I rely on, Bitrateviewer? or DVD2AVI?
2) What exactly is the significance of the Video type field in DVD2AVI?
3) What should be the settings in CCE for Interlaced source?

I would really appreciate any help in this regard.

Thanks.

[Matthew]

I live in au, and of the few region 4 dvds I've encoded so far, most seem to be odd like this, but are all progressive.

"Pic. structure: Frame"

Seems to be the most important line in telling whether the movie is progressive.

[colebert]

You should set:

Progressive, Zigzag, DVD compliant, Top field first, Linear Quant and whatever other defaults the guide recommends.


You're probably getting that misread because there a tiny bit of the movie (like the studio logo) thats interlaced and its throwing off bitrate viewer.


-cole

[Matthew]

colebert I can only speak for myself, but I always use the second or subsequent vob in BV, and still get these odd stats ;)

BTW *never* check upper field first in CCE.

[ronnylov]

Originally posted by Matthew
I live in au, and of the few region 4 dvds I've encoded so far, most seem to be odd like this, but are all progressive.

"Pic. structure: Frame"

Seems to be the most important line in telling whether the movie is progressive.

You can have pic structure frame and still have an interlaced clip.
Try encoding interlaced with CCE or TMPGEnc and analyze the results in bitrateviewer. It surely will say pic structure frame and interlaced. The only encoder I know can encode interlaced with field stucture is Canopus Procoder, but this function seems buggy at the moment in Procoder.

[slk001]

If you fed the first .VOB into bitrate viewer, you most likely got one of either the studio header or the FBI warning, which will most likely be interlaced. Bitrate viewer gets the encoding info from the initial header, which is NOT the movie's header. That is why DVD2AVI is telling you that the movie is FILM. Trust DVD2AVI over BRV, but only because it continually reads the headers and updates the video type. Matthew told you the proper proceedure - that is, fed in the SECOND .VOB (which should be entirely movie) into BRV and you will get the correct info.

But, you are correct on the settings shown by BRV as being interlaced. Particularly,

DCT Type: Field
Scan type: Alternate
Frame type: Interlaced

would all indicate interlaced video.

[jdobbs]

First, remember that in NTSC everything is interlaced -- because the NTSC standard is built on a field based interlaced picture. But that doesn't always mean that the "source" was interlaced. Most movies were shot as 24fps progressive images and are made to be interlaced through the telecine process...

Answers to your questions:

1) Which reading should I rely on, Bitrateviewer? or DVD2AVI?

Rely on DVD2AVI. It actually scans the source and can see the RFF flags that indicate that a 29.97fps stream is being created from a 23.976fps source. It will also show you the "hard" ones that switch back and forth. When you get to the 95% mark you mentioned it is obvious the original source was FILM... That way you can reencode at 23.976fps using CCE (getting the better quality) and then add the RFF flags back with PULLDOWN.EXE

2) What exactly is the significance of the Video type field in DVD2AVI?

As explained above. It will show you whether the original source comes from a movie or a video camera. You can use this information to determine the best way to reencode.

3) What should be the settings in CCE for Interlaced source?

For a truly interlaced source (the one you have as an example is not a truly interlaced source) you should not use Zig-Zag (it is specifically designed for progressive according to the CCE manual) and the Top Frame First depends should match the source.

[jbalakri]

Thanks to everyone for answering my question. Indeed, as suggested by many, I loaded VOB2 into bitrate viewer and this is what I got:

Num. of picture read: 31
Num. of picture read: 31
Stream type: MPEG-2 MP@ML VBR
Resolution: 720*480
Aspect ratio: 4:3 Generic
Framerate: 29.97
Nom. bitrate: 8230000 Bit/Sec
VBV buffer size: 112
Constrained param. flag: No
Chroma format: 4:2:0
DCT precision: 10
Pic. structure: Frame
Field topfirst: Yes
DCT type: Frame
Quantscale: Nonlinear
Scan type: ZigZag
Frame type: Progressive
Notes:


It is quite clear that this movie is indeed a progressive scan type. So, I guess just to be sure you should always load VOB2 or VOB3 in the Bitrate viewer to get an accurate reading. This clears up all my doubts.

Thanks again,
- Jay

[Matthew]

Originally posted by ronnylov


You can have pic structure frame and still have an interlaced clip.
Try encoding interlaced with CCE or TMPGEnc and analyze the results in bitrateviewer. It surely will say pic structure frame and interlaced. The only encoder I know can encode interlaced with field stucture is Canopus Procoder, but this function seems buggy at the moment in Procoder.

Now I'm really confused...this means I've encoded a couple of movies as progressive when all indications from DVD2AVI/bitrate viewer are that they are interlaced. And they've turned out fine. [BTW this is region 4 PAL].

[DL]

I recently did a backup of The Firm. After Decrypting and Ifoedit I used Bitrateview to look at the VOB. The first one showed Top field first = yes so just to be sure I looked at the third one and it also said the same. So I used my CCE and check the top field first box. The movie as you guessed was jerky. So I went back to the VOB's and double checked them. I checkk all 4 of them. Number 1 and 3 showed top field first = yes and 2&4 showed top field first = no. I reencoded unchecking top field first and all is fine. Can anyone comment on why the Vob's change field order?

Just would like to know so I dont make the same mistake again.

Thanks,
DL