How do you know - film versus video based...

Good question, one to which I would like the answer to...that said, the Lumagen has a function that can be disabled/enabled to determine whether the video signal is film or video which I frequently use to ensure that I am using the preferred de-interlacing alforithm...for those interested the function is disabled/enabled by pressing MENU+0+9+1+8

Virtually all movies are 24 fps film-based. Sports and concert DVDs are usually 30 fps video-based. 99% + of all material will be in one of these two formats. However, there are other less-common formats that require special deinterlacing attention.

Because of some of the complications you mention, leaving the deinterlacing mode in Auto is probably the best choice.

If you could single step through the fields or frames using a VCR or digital video recorder, you would notice that film source has 24 poses per second representing the 24 film frames per second in the 60 or so video fields/.frames per second while video source may have every field or frame unique.

The "wrong" setting usually results in more frequent occurrences of serrated or feathered side edges of moving objects in the picture.

Generally the need to select film versus video de-interlacing manually suggests a mediocre de-interlacer.

I do happen to know that the Lumagen and Silicon Image de-interlacers are quite good at selecting automatically as needed and I heard that one of those manufacturers (I forgot which) put an unnecessary manual selection in "due to popular demand".

Video hints:
http://members.aol.com/ajaynejr/video.htm

To extend the question a bit, the dvd players perform some manipulation on DVDs if they are film based. (I think).

So if the DVD player is manipulating it this will mess up the processing of a video processor. Correct? I am assuming I can/should disable as much processing as possible from my DVD . Correct and send 480i to my system?

In some cases I can't seem to disable the pulldown etc. (cheap DVD player).

Thanks,
Bob

PS I am sending my video through my Iscan HD.

Film source on regular NTSC DVD is normally stored as 24 fps progressive. This takes up 4/5'th the space as video source and is done to allow a longer playing time per disk compared with treating it as video source.

All regular NTSC DVD players take the 24 fps progressive and convert it to 60 fields per second interlaced with 3-2 pulldown imparted If the player is progressive or has upconverting it will treat the aforementioned interlaced video as an intermediate video signal and de-interlace it. The finished 60 fps progressive video will still have 3-2 pulldown and ideally should have matching even and odd fields in every frame as a result of 3-2 pulldown sensing during de-interlacing.

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Isn't the player/processor supposed to detect this automatically?

Stage 1 of the DVD player (MPEG decoder) detects this automatically.

Processing down the line relies on flags outside the pixel fields or relies on analyzing the pixel content (taking hints from the video) to generate or regenerate full 480p frames. The better processings always analyze the pixel content since flagging does not always correctly mark the first of each matching pair and the flags are accessible only to processing within a DVD player as its stage 2 (de-interlacing if present).

generally speaking, most movies and shows originate from 24fps.

music videos and sports often derive from video.

you can't generalise, Ofer.


I'd say most video clips derrive from film.


I use the Crystalio2 with it's film/video detection LED's on the panel to verify.

for video clips, it's sometimes very hard to determine if it's sourced from PAL or
NTSC sources. Sometimes, an US band can have their clip produced in PAL and an
UK group in NTSC.

even UK directors may produce their clips in NTSC

for example, a music video clip shown on US television of an UK band can't
detect FILM due to PAL-NTSC transcoding and the same applies to clips
shown on MTV,VH-1,VH-1 Classic UK and Europe (50Hz PAL)

it sometimes gets so confusing, when for instance a old clip is not available
in their library in it's original form , like a 25 fps PAL originated clip transcoded
to NTSC and back to PAL. mostly it can be spotted due to it's extreme softness
and weird judder.

one example is the Genesis Video Show DVD, I bought both PAL and NTSC
version and there are clips that still aren't in their original state.

one other example is the New Order DVD. The Music Companies are getting so
lazy and don't produce the DVD's in their original PAL version. The disc get's
transcoded to NTSC and released all over the world, it's sickening

even frame by frame analysis sometimes can't tell if it originally was film or video,
PAL or NTSC , transcoded or not


it's one of my hobbies to collect music clips from different sources

(TV,Sat,U-matic,LD,DVD,Beta,...)

I keep a detailed list of 25000 music clips about their original source format.


Michael

Usually U.S. 24 fps films are put on PAL video by being run at 25 fps and with 2-2 pulldown imparted. You can single step using a (PAL) VCR and see the repeating fields but de-interlacers have a harder time compared with dealing with 3-2 pulldown.

There are some 30 fps U.S. film sources put on video with 2-2 pulldown. This, too, can be seen by single stepping using a (NTSC) VCR.

Ordinary PAL-NTSC or NTSC-PAL conversion does not assume that the source has either 3-2 pulldown or 2-2 pulldown. If the source had either, chances are that the result will have repeating fields in an irregular pattern.

I use a Denon 2900 which will display F, V, or G in the display window (for Film, Video, and presumably Graphics).

I don't know where the player derives this data from (probably the SiL504 or disk flags). Regardless, it is innacurate (jumps around from F/V/G during playback on a seemlingly arbitrary basis). If the player is clueless, it's probably not easily determined.

The player displays the F, V, or G (2-2 pulldown) depending on the way its stage 2 is treating the video.

It is not unusual for scene changes to result in departures from a uniform 3-2-3-2-3-2 cadence of 3-2 pulldown.

If examining the pixel content of two consecutive fields results in too many content discrepencies that the processing does not choose to do a full weave, then the V indicator comes on. A good processing can do F much of the time by examining the pixel content even when flag that are incorrect are present.

Some AVS members with long experience in the TV/video/film world say they can very rapidly spot differences between 24p-captured film and 1080i/720p video based on the appearance of motion. As mentioned, for movies on a DVD, it's undoubtedly 24 fps filming, although TV cameras can emulate film with 24PsF (segmented frame) capture. Trailers on DVDs might well be video captured at 1080/60i (60 TV fields or half-frames) per second (U.S. formats).

HDTV is a hodgepodge of formats, although 24 fps, film or tapes, requires 2-3 pulldown (extra identical TV fields) for conversion to the 1080/60i broadcast standard. 24 fps images have a distinctive jerkiness that becomes easier to identify with experience. And obviously knowing you're viewing a drama (24 fps) versus non-fiction helps identify the likely format.

One daytime soap, CBS's The Young and the Restless, is one of the rare dramas video taped at 1080/60i, and the smoother motion is evident, although not as obvious as with 1080/60i captured outside a TV studio. 1080/60i capture often adds a certain 'wow-effect' (greater sharpness) compared to 24-fps film/tape images (often 'snapped' at 1/48th second). The added sharpness can, in part, be caused by 1/60-sec image snapshots versus 24-fps images; blurring judder can result when most displays show 24p at 60 Hz. Also, film processing, such as telecining from mediocre prints, can lessen image sharpness, even though film still provides better contrast and 'less-flat' images. -- John

It's getting harder to differentiate but I can still pick out film from hd-video or hd 24p just by looking at it. That said I don't really bother with it, "auto" works for me, I just let the Lumagen HDQ handle it.