Avisynth Script Soft Telecine NTSC DVD

[norlane]

This is my reading on soft and hard telecine NTSC DVD
My Question follows my reading below thankx in advance for any help.

Hard telecining
interlacing on 2 frames out of every 5 frames. This pattern of 3 progressive frames and 2 interlaced frames is echoed in another name for this process: 3:2 pulldown.

Soft Telecine
Now, a lot of DVDs don't use hard telecining. This is a good thing. Instead, they use soft telecining. This preserves the 24fps content for the DVD. It just uses something called "repeat flags" to tell the DVD player "show this field extra long," instead of actually storing the duplicated frame on disc. It saves space, while still technically being 30fps because of the repeat flags.

Soft telecining looks like this:

Frame 1: A1A2 (Top, Bottom, Repeat Top)
Frame 2: B2B1 (Bottom, Top)
Frame 3: C2C1 (Bottom, Top, Repeat Bottom)
Frame 4: D1D2 (Top, Bottom)

Meaning it can be presented at 30fps exactly like the hard-telecined example above. It also makes things easy for computers and progressive scan DVD players, which can just ignore the repeat flags and frame order to decode the video at film speed, with no visible interlacing.


Process
Hard telecined content, in contrast, has to go through a decimation or inverse telecine (IVTC) process to pullup to film speed. Inverse telecine undoes the hard telecine process. It reverts those 5 frames to the original 4, getting rid of the interlacing artifacts on 2 of every 5 frames. This pulls it up to film speed.

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My Question is for Soft Telecine NTSC DVD structure what avisynth script do i use.
If i use honor pulldown flags in DGIndex.
If there are no Interlaced frames i presume i dont need to use a deinterlacing functions


This is what i would use for Hard telecining:
#source parsing
eg. DGDecode_mpeg2source("VTS_01_1.d2v", cpu=0)

#deinterlacing functions
eg. tfm(mode=4,pp=0,slow=2).tdecimate()

#cropping
eg. crop()

[manono]

Originally Posted by norlane

My Question is for Soft Telecine NTSC DVD structure what avisynth script do i use.

Assuming you proved to yourself it's all soft telecine, you make the D2V using DGIndex with the Field Operation set for 'Forced Film'. That gives you a progressive 23.976fps video and you need do nothing in the script.

[norlane]

thankx for you reply
What is the best method for proving it is all soft telecine or hard telecine video.

thankx.

[manono]

You can run the DGIndex Preview to get an idea first. Then you can make the D2V using 'HonorPulldown Flags' or 'Forced Film'. Afterwards you can open the D2V in Notepad and at the bottom it gives the percentage of Film or Video.

[norlane]

ok thankx for that .
So if its 100 percent Film it is soft telecine.
If it is say only 98 percent film the other 2 percent is interlaced frames
ie hard telecine. is that right?

[manono]

Originally Posted by norlane

If it is say only 98 percent film the other 2 percent is interlaced frames
ie hard telecine. is that right?

No. 98% is soft telecine and the other 2% is either hard telecine or it's really interlaced (all frames interlaced). However, the chances are good it's hard telecine but the only sure way to know is to find that part and have a look. It's often at the beginning and might be logos. Sometimes it's at chapter changes. Sometimes it's end credits.

You can look through the D2V for the parts that don't go 0 1 2 3 0 1 2 3, but either 0 0 0 0 0 or 2 2 2 2 2

[norlane]

awsome thankx for the reply

[norlane]

would like to follow through with your method of analysing the dvd type.
i opened DGIndex and made a d2v file using Honor Pulldown Flags.

I opened the file with avisynth and stepped through one frame at a time.
i looked through each frame and it showed 3 progressive frames and
2 interlace or (hard telecined) frames.

i opened the d2v file with note pad and down the bottom it
showed

d00 6 4 160622592 0 1 36 d2 f3 f0 e1 f2 f3 e0 f1 f2 e3 f0 e1
d00 6 4 161099776 0 1 36 d2 f3 f0 e1 f2 f3 e0 f1 f2 e3 f0 e1
d00 6 4 161574912 0 1 36 d2 f3 f0 e1 f2 f3 e0 f1 f2 e3 f0 e1
d00 6 4 161964032 0 1 36 d2 f3 f0 e1 f2 f3 e0 f1 f2 e3 f0 e1
d00 6 4 162111488 0 1 36 d2 f3 f0 e1 f2 f3 e0 f1 f2 e3 f0 e1
d00 6 4 162140160 0 1 36 d2 f3 f0 e1 f2 f3 e0 f1 f2 e3 f0 e1
d00 6 4 162166784 0 1 36 d2 f3 f0 e1 f2 f3 e0
d00 6 4 162179072 0 1 36 d1 f2 f3 e0 f1 e2 ff

FINISHED 100.00% FILM

question: you said to
You can look through the D2V for the parts that don't go 0 1 2 3 0 1 2 3, but either 0 0 0 0 0 or 2 2 2 2 2

do i just filck from frame to frame in avisynth or look at the d2v file in note pad for these numbers.

thankx in advance .

[manono]

Originally Posted by norlane

i looked through each frame and it showed 3 progressive frames and
2 interlace or (hard telecined) frames.

I said if it was film (encoded progressively with pulldown applied) to make the D2V using Forced Film. Then the whole thing is 23.976 and progressive.

you said to
You can look through the D2V for the parts that don't go 0 1 2 3 0 1 2 3, but either 0 0 0 0 0 or 2 2 2 2 2

If it's 100% film you'll find none of that.

[norlane]

when i asked
do i just filck from frame to frame in avisynth or look at the d2v file in note pad for these numbers.

i just wanted to know how the number thing worked in general for analysing

[manono]

I guess I don't understand what you're asking. There's a good explanation of what's in a D2V near the bottom of the DGIndex User Manual, which you should already have, or which can be found here:

http://neuron2.net/dgmpgdec/DGIndexManual.html

There's also an old but still very useful FAQ here:

http://forum.doom9.org/showthread.php?t=87809

[norlane]

thankx for the linkx and ur help will read these.