Help with 24p "Normal" footage Compression

F

farfromsubtle

Well-known member
I am pulling my hair out over this. I have edited an entire project on a 29.97 timeline, using footage shot with the "F5" setting. Everything edited smoothly, the footage looks beautifil in FCP, and the exported final project looks fine when opened in Quicktime.

However, I am having ALOT of trouble compressing the film for the web. Interlaced frames pop up all over the place. They are gone when I use the MP4 preset for NTSC High Quality Progressive, but when I change 320x240 to 640x480, the interlacing comes back... which is really wierd, since that should have NO effect.

Can someone help me out?

Edit: Here are somescreen shots and some of the output footage...

1. This is my sequence settings...

settings01.jpg


2. Here is the easy setup profile I chose:

settings02.jpg


3. Here is what happens when I compress using NTSC large Progressive, HOORAY! It doesn't encode the interlacing!

settings03.jpg


4. But, the default for this preset is 320x240... here is what happns when I change NOTHING but the size to 640x480 OR 100% of source:

settings05.jpg


5. And this is a high quality DVD encoding on the 60 minute High Quality preset:

settings06.jpg


So... why does it do this? Where is the setting that makes it progressive? Why does changing the frame size effect cadance? I am going insane!

Here is the sample clip if anyone wants to be my hero and play around with this to tell me what settings to use and why I am a more. Obviously, this clip will only be of use to you if you have FCP.

Thanks in advance guys!
 
If the size is an even ratio of the original size and you're stopped on an interlace frame it will show the interlacing.

You aren't dealing with progressive. You shot progressive but are editing it in a 29.97 timeline which is interlaced. This is fine for video output.
If you do want no interlacing (computer display, web playback, etc) then:
1. Remove pulldown on original and edit on 23.98 timeline (note you can't remove pullown on a 29.97 edited sequence since you may be missing fields and the cadence can change every cut)
or
2. Somewhere in the pipeline or in the compressor specify to de-interlace the footage. This will cause it to drop one field or to blend them together. (loss of vertical quality)

Play it back in real tiem in any case and see if it's objectionable.
 
So what you are saying, is that by going down to 320x240 it has given me the illusion that I have de-interlaced, but in actuality, it has just lost every-other-line and thus, look normal (in the first example).

This makes sense to me... Does this mean that any footage from a 29.97 timeline always has to be down-rezed like this?
 
29.97 is interlaced. TV = not a problem Computer/web = possibly annoying , especially if you stop on a frame.

If yo uwant to remove the interlacing you either plan from the beginning to deal only with progressive footage and editing or de-interlace (or potential resize that would remove the odd/even line differences)
 
I followed the advice on this website for capturing 24p normal: http://www.kenstone.net/fcp_homepage/24p_in_FCP_nattress.html

They say: Because 24p Normal uses “normal” 3:2 pulldown to embed the 24p in a normal NTSC DV video, you can capture and edit just as normal DV NTSC.

I was under the impression that I would still have the benefit of progressive footage... What is the point of progressive normal when you still have interlaced video?
 
You still have the 24fps look and you can show it on any video, go out to a video tape, and intercut with 60i footage. as you note you do not have progressive images becuase in order to go from 24fps -> 30 it has to take parts of frames (fields) and spread them out (interlaced)
 
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