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Mpeg encode ??

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This is weird. When I encode this stuff with CEsp I get the same frame rate I put in 23.9blah.

Well, when I try to import those mpegs into DVD studio 3 it say non-standard frame rate & won't let them in. Same thing in TMPGEnc.

When I use compressor or change the frame rate in CEsp to a 29.9blah frame rate they come in just fine.

What's the story & how is this going to effect my audio sync?
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When you enocde your video with 23,976 you need to enable the 3:2 pulldown flag in the mpeg stream to get it NTSC DVD compliant. There are several tools that can do this .
Some DVD authoring programs even do this conversion themself (e.g. dvdlab).
This will not effect audio sync. The new mpeg video stream has the same duration (just higher fps).

http://guiguy.wminds.com/downloads/pulldownbatchfe/

Greetings
grisan.
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This will put in 2-3 flags as well.

<span class=“Italics”>MeBeJedi: Sadly, I believe the prequels are beyond repair.
<span class=“Bold”>JediRandy: They’re certainly beyond any repair you’re capable of making.</span></span>

<span class=“Italics”>MeBeJedi: You aren’t one of us.
<span class=“Bold”>Go-Mer-Tonic: I can’t say I find that very disappointing.</span></span>

<span class=“Italics”>JediRandy: I won’t suck as much as a fan edit.</span>

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so I get this stuff coverted from a 3:2 pulldown to a 24fps progressive stream & now I'm going back to a 29.9blah stream by redoing the 3:2 pulldown. I've noticed that this is now 29.9blas fps and it is all progressive frame unlike what I started with which had those 2 nasty interlaced frames.

Is the only piont in this conversion, filtering and encodeing?

What are the benifits of jumping threw some many hoops?

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When you convert from 30fps to 24fps, you have far fewer frames to encode for the same amount of "video". This means a smaller file size (or, the same file size with better quality.)

For example, I encoded my 18 second lightsaber scene as 24 and 30fps. The 24fps segment was 3 MBs smaller. Over a 2-hour movie, that's approxiamtely 300 Mbs of wasted space.

Point being, the presentation of the movie will not change - you are simply compressing it to fit into a smaller package (which can easily be expanded and recreated digitally.)

<span class=“Italics”>MeBeJedi: Sadly, I believe the prequels are beyond repair.
<span class=“Bold”>JediRandy: They’re certainly beyond any repair you’re capable of making.</span></span>

<span class=“Italics”>MeBeJedi: You aren’t one of us.
<span class=“Bold”>Go-Mer-Tonic: I can’t say I find that very disappointing.</span></span>

<span class=“Italics”>JediRandy: I won’t suck as much as a fan edit.</span>

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I'm not sure how it is smaller when it is converted back to 30fps?
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fps=frames per second

In a nutshell, films are originally recorded at 24fps. However, television transmits at 30fps. In order to make film-based material run smoothly at the higher rate, 2 out of every 4 frames are used to create a new composite frame (this is the frame where you would see two ghost images, rather than one clean image). Where once there were 4 frames, now there are 5. (This is where 2-3 comes into play - 2 frames --> new composite made --> 3 frames altogether [the original 2, plus one extra] The next two frames are left alone, and the pattern repeats with the two frames after those.)

Frames

A B C D E F G H-- 24 fps
\...4..../\...4..../

A AB B C D E EF F G H -- 30 fps
\......5....../\......5...../

What IVTC does is remove that extra frame (which is essentially a copy of two other frames anyways.) Laserdisc requires that the extra frame be in there, because it's a simple analog playback system. DVD, however, is capable of many new tricks, due to its digital nature. Thus, instead of requiring the extra frame to be in the footage, we can use programs like Pulldown.exe to place flags where this extra frame should be. When the DVD player reads the flag, it creates the extra frame on the fly. Thus, our 24fps MPEG is decoded and changed into a 30fps video stream. Since the DVD player is able to extract and create this extra information from the existing frames, it saves us one frame for every 4 frames. When you realize that ANH is 170,000 frames, it turns out that encoding to 30fps creates @43,000 extra frames! More frames means a bigger file size. If we wanted a file size of 4 Gbs, then the more frames we have, the higher compression we must use. Higher compression = lower overall bit rate. Since we can get the same picture with 24fps or 30 fps, it makes more sense to save at 24fps, using a higher bit rate per frame, and make the DVD player do all the heavy lifting.

I hope that makes sense...

<span class=“Italics”>MeBeJedi: Sadly, I believe the prequels are beyond repair.
<span class=“Bold”>JediRandy: They’re certainly beyond any repair you’re capable of making.</span></span>

<span class=“Italics”>MeBeJedi: You aren’t one of us.
<span class=“Bold”>Go-Mer-Tonic: I can’t say I find that very disappointing.</span></span>

<span class=“Italics”>JediRandy: I won’t suck as much as a fan edit.</span>

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Originally posted by: khamul02
I'm not sure how it is smaller when it is converted back to 30fps?


It is not really convert to 29,97 fps. You just enabled a flag in the mpeg stream that tells the player software to perform a 3:2 pulldown while playing.
This basically converts a group of 4 frames into a group of 5 frames. This happens 6 times per second. (24 fps divided into 6 groups per second == 4 frames per group, then create 5 frames out of these 4 in every group and still playback these 6 groups per seconds == equals 30 fps). The new frames are created by splitting frames into even and odd fields (think line numbers) and put together in a specific way.
Here is a more exact and technical description of this procedure:
http://www.dvdfile.com/news/special_report/production_a_z/3_2_pulldown.htm

You could just capture your LDs at 29,97 fps and encode it to mpeg with 29,97 fps interlaced mode, but 23,976 fps progressive mode usually gives much better results, so most people try to restore the original 24 fps from the laserdisc material by applying inverse telecine.

Greetings
Grisan
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Got it. the mpeg doesn't contain 30fps. It only contains the 24fps we put in and a flag to generate extra frames on the fly.

COOL!!

Thanks for all the explanation.
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No problem.

<span class=“Italics”>MeBeJedi: Sadly, I believe the prequels are beyond repair.
<span class=“Bold”>JediRandy: They’re certainly beyond any repair you’re capable of making.</span></span>

<span class=“Italics”>MeBeJedi: You aren’t one of us.
<span class=“Bold”>Go-Mer-Tonic: I can’t say I find that very disappointing.</span></span>

<span class=“Italics”>JediRandy: I won’t suck as much as a fan edit.</span>