Understanding mediainfo results around interlacing and frame rate

[RoscoeMerriweather]

I have been playing around with upscaling some older TV shows from DVD. The first step has been trying to figure out whether or not they are interlaced. I have been doing a combination of looking at the data reported by mediainfo and stepping through the videos to look for combing. The latter seems to be the much more reliable way. I have actually been finding the data from mediainfo pretty confusing. These are five episodes from the same season of a TV show, all ripped from the same DVD set with MakeMKV. What is surprising/confusing me is that they are all different. Episodes 1 and 4 claim to be progressive and indicate a 2:3 pulldown, which I think means they are telecined? They also have a similar frame rate and original frame rate. Episode 2 reports interlacing. Episodes 3 and 5 don't report any kind of scan type. 2, 3, and 5 have a significant difference between frame rate and original frame rate. When I step through frames in parts with a lot of motion, I can see combing in episodes 2, 3, and 5, but I couldn't find any in 1 and 4. I guess that I expected every episode of a TV season would be more or less the same, but that doesn't seem to be the case. Can you help me to better understand this information?

Episode 1
Frame rate : 23.976 (23976/1000) FPS
Original frame rate : 23.976 (24000/1001) FPS
Scan type : Progressive
Scan order : 2:3 Pulldown

Episode 2
Frame rate : 25.058 FPS
Original frame rate : 29.970 (30000/1001) FPS
Scan type : Interlaced
Scan order : Top Field First

Episode 3
Frame rate : 24.469 FPS
Original frame rate : 29.970 (30000/1001) FPS

Episode 4
Frame rate : 24.400 FPS
Original frame rate : 23.976 (24000/1001) FPS
Scan type : Progressive
Scan order : 2:3 Pulldown

Episode 5
Frame rate : 24.302 FPS
Original frame rate : 29.970 (30000/1001) FPS

[Sharc]

There is only one way:
Analyze the video manually by separating the fields and stepping through the fields to draw your own conclusions.
MediaInfo is not always correct as it doesn't have eyes.
It is well possible that different episodes are authored in different formats, as long as these formats are DVD compliant. Also, the ripping tool may introduce its own 'rules'....

[Selur]

Episode 1
Frame rate : 23.976 (23976/1000) FPS
Original frame rate : 23.976 (24000/1001) FPS
Scan type : Progressive
Scan order : 2:3 Pulldown

Episode 4
Frame rate : 24.400 FPS
Original frame rate : 23.976 (24000/1001) FPS
Scan type : Progressive
Scan order : 2:3 Pulldown

-> source is 29.97fps soft telecined

Episode 2
Frame rate : 25.058 FPS
Original frame rate : 29.970 (30000/1001) FPS
Scan type : Interlaced
Scan order : Top Field First

Episode 3
Frame rate : 24.469 FPS
Original frame rate : 29.970 (30000/1001) FPS

Episode 5
Frame rate : 24.302 FPS
Original frame rate : 29.970 (30000/1001) FPS

source is 29.97fps and either normal interlaced, telecine or progressive, like Sharc wrote, you need to check yourself.

Cu Selur

[poisondeathray]

Also mediainfo only looks at the 1st part of the video. Episode 1 and 4 might be 100% soft telecine , or 50%, or 1%. You can't tell with mediainfo . e.g. the 2nd minute might be interlaced content, or credits might be interlaced content.

[Selur]

Sure, the source might always be fubar like Babylon 5 and older anime stuff, so a wild mix of content, so checking the preview of the source after applying the selected methods for handling with combing is always a good idea.

[RoscoeMerriweather]

OK, that is all very helpful. This is considerably more complex than I expected. So far, to try to detect interlacing, I open the video in mplayer and step through one frame at a time. I can definitely see combing in some videos, particularly when there is fast movement, but I am not so sure the rest of the time. Usually, where I see combing in these videos, it is 3 frames without and then 2 with. Is that an indication that I am dealing with telecine rather than interlacing? I did some reading about that yesterday, but I think it is going to take some experience to sink in. Is there a better tool for this than just stepping through with a video player? Also, I think that the comment suggesting that the credits might be interlaced, while the rest of the content is different is correct! It is much easier to pick out combing in the credits than the rest of the episode. What is the process to deinterlace and/or detelecine a video that is not consistent? Do I need to chop it up into pieces and process them separately?

[manono]

...all ripped from the same DVD set with MakeMKV.

There's your mistake. Decrypt using a real decrypter, like DVD Decrypter, if possible. MakeMKV screws everything up.
Then open a resulting VOB in something like VDub2 , find a part with movement and step through the frames one-by-one. Something like DGIndex can tell you if the Vobs are soft telecined, hard telecined or a mix of the two.
Yes, soft telecine shows as 3 progressive followed by 2 interlaced frames. But so does hard telecine. Interlaced content shows all frames as interlaced during movement. Both hard teleceine and true interlace is encoded as interlaced. Soft telecine is encoded as progressive with 3:2 pulldown.
No, you don't have to chop anything into pieces. You can IVTC using AviSynth quite easily.

[Sharc]

Usually, where I see combing in these videos, it is 3 frames without and then 2 with. Is that an indication that I am dealing with telecine rather than interlacing?

Yes, this is an indication for telecined video.

Is there a better tool for this than just stepping through with a video player?

VirtualDub2, Avisynth+, FFmpeg ....
In principle one has to separate the fields and analyze the sequence for scenes with motion by stepping through the fields. So there is manual work involved, and your eyes.