norlane
5th November 2012, 22:44
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()
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.
*********************************
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()