MPEG2 render

HerzogisGod

HerzogisGod

Well-known member
from what ive been reading, once my timelie is rendered mpeg2 ntsc, it will be an interlaced timeline and play well on televisions. does this mean it will play poorly on progressive computer monitors? do computer moniters automatically deinterlace? also, do progressive televisions automatically seinterlace? The only time my project looks great on my television, which is progressive, is when I render interlaced. This doesnt make sense to me as a progressive render should look better... but it doesn't. Anyway, I am sending my project in to dismakers in a few weeks as an AVI file which they will then convert to MPEG2. I m having them author my project and get it ready with propr codecs etc. Im wondering if I should render my AVI file Progressive or Interlaced. What do you think?
 
You really are not providing enough info to give an informed answer.

When you say NTSC, are you talking about Standard Definition NTSC 29.97???
 
Your monitor doesn't deinterlace, but your software player probably does (or can be set to do so).
 
By monitor do you mean my tv? What is my software player? Will the customers im selling the dvd to have systems that deinterlace? So I should render in progressive? I also read that MPEG2 format is interlaced regardless of what format is used in the render.
 
I meant your computer monitor (which you had asked about). When you play an mpeg file on a computer, some form of software player (Mediaplayer or QuickTime player, for example) is being used. They can deinterlace the footage, which is why commercial DVDs, which are interlaced mpeg2, usually look fine on a computer

Edit: it is certainly possible to have progressive mpeg2, but if you are making DVDs they should be rendered interlaced.
 
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99.9% of Hollywood movies are encoded progressive with soft pulldown flags

This means 23.976 progressive content. When authoring, 3:2 pulldown TFF/RFF flags output a 59.94 interlaced signal. So in a sense you can call it "interlaced DVD". But it really isn't. Note both the content is progressive, and it's encoded progressive MPEG2. Progressive standalone DVD players (99.99% of the DVD players in the last 5-10 years) will remove the pulldown and output the progressive frames.

"Hard pulldown" means it's 23.976 progressive content, but encoded interlaced. Much lower quality, much less efficient, because you are encoding 25% extra frames , and also MPEG2 motion vectors get terminated early (interrupted across fields, and field repeats)
 
PDR said:
99.9% of Hollywood movies are encoded progressive with soft pulldown flags
Click to expand...

Well yes, but they originate from either 24 frame or 23.976 originals.

He is starting with interlaced SD 29.97 and going to interlaced SD 29.97.
I'm not sure where the confusion is from unless the OP does not have a proper monitoring environment setup.
 
David W. Jones said:
Well yes, but they originate from either 24 frame or 23.976 originals.

He is starting with interlaced SD 29.97 and going to interlaced SD 29.97.
I'm not sure where the confusion is from unless the OP does not have a proper monitoring environment setup.
Click to expand...

My bad. For some reason I thought he was too
 
My source footage is 24P, shot on Panasonic HVX200. I still find it odd that when I set up an interlaced project timeline and render out interlaced, my 480p flat screen television plays the footage clear and smooth. Perhaps the television is deinterlacing??? When I run a version of the film that was rendered progressive the images look fuzzy and out of focus, by comparrision. I always set the frame rate on my time line and in my render for 29.97, NOT 24 or 23.967. When I have experimented in the past with these last two setting, the footage was chopp and unwatchable. This is another confusing issue for me see as the original footage was shot 24p. But what Im most interested in is my future customers and their viewing experience.
 
In the end, I will probably set up a progressive time line, 29.97 frame rate, then render in progressive at the same frame rate. The picture on my television is sub-par, but this logically this makes the most sense. Besides as I mentioned, I read that once the project is converted from AVI to MPEG2 it doesnt matter what the original was rendered at. The material becomes NTSC interlaced. This was what I read
 
Sorry, from your earlier post I thought your footage originated at 29.97 SD.

When you say the original footage was 24p, was it really 24pA or 23.976 footage?

By the way encoding in MPEG2 does not automatically make something NTSC interlaced.

If you are having DiscMakers do the setup work for your DVD, I would drop them a line and find out what they really need from you as far as specs go.

Good Luck!

Dave
 
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HerzogisGod said:
In the end, I will probably set up a progressive time line, 29.97 frame rate, then render in progressive at the same frame rate. The picture on my television is sub-par, but this logically this makes the most sense. Besides as I mentioned, I read that once the project is converted from AVI to MPEG2 it doesnt matter what the original was rendered at. The material becomes NTSC interlaced. This was what I read
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No, that's the last thing you want to do

The HVX200 when using 24p shoots with 3:2 pulldown to begin with. You need to remove pulldown to get the original progressive 24p frames.

A 29.97p timeline and export settings will cause every 5th frame to be duplicated = jerky playback

A 59.94i timeline and export settings (or sometimes called 29.97i, it's the same thing, just different terminology) timeline will give you the hard pulldown scenario described earlier - it will work, but give you lower quality. This is the same thing as 24p in 59.94i

Deinterlacing 3:2 pulldown 24p material will decrease the vertical resolution in half , and give you every 5th frame repeated. You don't want to deinterlace anywhere this scenario.

Software players are unreliable to determine playback issues. Some will deinterlace, some won't. It depends on the specfic player, and how the filters are configured.

The original format does matter. Because that's usually how the director, DP intended it to be viewed.
 
My NLE does not have pulldown option. I use SpeedEdit . It has options for upper and lower fields. Progressive. Automatic from file and Ignore. Plus a couple of dozen frame rate options. Now im really confused
 
I'm not familiar with SpeedEdit, but if it doesn't have option to remove pulldown, your only option is to treat it as 59.94i

This is bad because your edit points might disrupt a cycle, so you will get combing artifacts on your cuts. Also it's lower quality encoding result (the hard pulldown discussion where you are encoding 25% extra for nothing)

I suggest getting a program that handles your material correctly
 
Is there a plugin I can buy to perform the pulldown? Can pulldown be performed after rendering in an authoring program?
 
HerzogisGod said:
Is there a plugin I can buy to perform the pulldown? Can pulldown be performed after rendering in an authoring program?
Click to expand...

I'm not familar with SpeedEdit, so I don't know what plugins are available

Note - It's REMOVAL of 3:2 pulldown for the HVX stream. This gives you back the original progressive 24p stream to edit (actually 23.976 or more precisely 24000/1001). This means your edits are on real , unique frames, not duplicate fields - so there is no risk of interlaced cuts and combing artifacts

When you export , either the encoder or authoring program will insert soft pulldown flags, this ADDS 3:2 pulldown, so that 24p stream "looks" like a 59.94i signal. As mentioned earlier, the vast majority of DVD players are flag readers and will REMOVE the pulldown when playing, giving you the original 24p stream back. On a 60Hz HDTV screen, 24p will have 3frame-2frames repeated, unless your HDTV model has some sort of frame interpolation modes (some resample and give you smooth playback- but that is another disucssion entirely). This is normal cadence, and all film DVD's (theatrical Hollywood DVD's) look like this

I believe your problem is your editing software
 
I made 4 tests renders. The best on both progressive flat screen tv ans computer monitor was Progressive time line... progressive render and AVI format. When I burned this to a dvd it played back sharp and clear. 29.97 frame rate as well. Not exactly sure what it all means but I have to go with something
 
Are you sure? Theoretically that will give you poor results. Every 5th frame will be duplicated = choppy playback (I mean even more choppy than "normal" 24p). Chances are your program is deinterlacing the footage as well = low resolution, deinterlacing artifacts

But maybe something else is going on? As I mentioned earlier, I'm not familiar with SpeedEdit - maybe it's doing something correctly?
 
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