How to correctly import H.264 Videos?

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How to correctly import H.264 Videos?

I have this problem since i use iMovie 08. It has not changed with iMovie 09. I am using a Sanyo Xacti HD-700 Camera that creates fine H.264 Videos with the following details:

Format: H.264, 1280 x 720, 16,7 Mill. AAC, Stereo (L R), 48,000 kHz
FPS: 29,97
*Playback FPS:* 30

The videofiles are fine and playback without any stutter if i play them with Quick Time Player. But if i import them to iMovie (08 or 09) the movies are "stuttering" - a good example can be found here: http://vimeo.com/3111485 (view the panorama views). As the original H.264 seems to be fine i think i am doing something wrong with the import into iMovie. Do i need to switch the videostandard to NTSC in the iMovie Settings (PAL is default here in Austria with 25 FPS and there is an option in iMovie to switch this to NTSC with 30 FPS. But as far as i know this setting does not effect anything using importet H.264 videos, right?

Can You give me any hint how to eliminate this boring stuttering in iMovie? Thanks in advance for Your help!

Michael

iMac 2.4GHz Intel Core 2 Duo 3 GB Ram, Mac OS X (10.5.6)

Posted on Feb 6, 2009 3:41 PM

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Answer 1

Feb 6, 2009 7:26 PM in response to cybermike

I suggest you convert your video files from h.264 to Apple Intermediate Codec before importing into iMovie. You can do this with MPEG Streamclip or with QuickTime Pro.

After you create your movie, you can Share using QuickTIme using h.264, 1280x720 for uploading to Vimeo or YouTube.

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Answer 2

cybermike Author

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Feb 7, 2009 1:01 AM in response to AppleMan1958

Thanks for the answer, but mhmm, i can´t believe that this workaround is good as a permanent solution. H.264 is an open Standard and as far as i know Apple officially supports it. Can anybody explain WHY the videos stutter? The original H.264 videos are great and they are unchanged after i import them into iMovie (they are moved to the iMovie Events folder). Only the created output from iMovie stutters. I am not sure but can it have something to do with different FPS rates?

Any more hints?

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Answer 3

Feb 7, 2009 2:04 AM in response to cybermike

Like you guessed switching to NTST 30fps should fix this problem. 30p movie in 25p timeline has to drop every 6th frame, and it is worse than playing back 25p in 30p timeline where every 5th frame needs to be doubled. There is no easy way to convert between 25p and 30p smoothly. I've always wondered why Sanyo wouldn't make a 25p version product for PAL countries.

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Answer 4

cybermike Author

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Feb 7, 2009 2:34 AM in response to Euisung Lee

So just to be sure that i really understand: I have to switch to NTSC 30fps if i want to import Videos from my Sanyo and back to PAL 25fps for importing Videos from cameras using 25fps, right? As soon as the videos are imported it does not make a difference what setting is used, right?

And exporting using Quicktime should always have the same FPS as the original video-material, right?

Thanks for guiding a newbie 🙂

Michael

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Answer 5

Feb 7, 2009 3:19 AM in response to cybermike

Unfortunately that is not the case. iMovie imports your h264 natively so whether you do it in NTSC or PAL mode your original 30p movie will be used, and you need 30p timeline for that. By nature 30p can't live in 25p timeline happily.

Nor does iMovie adaptively changes fps for the clip's original ftp. I tried to use 24p clip in NTSC mode and the end result was 30p, with every 5th frame doubled to make up for the difference.

Even if you choose to convert your 30p movie to 25p using other tools (JES deinterlacer or MPEG streamclip) your problem won't completely go away. You'll be only embeding the jittery motion into your converted clip. Perhaps those tools can provide some options to smooth out the jitteriness, but I doubt that it'll be enough.

You can use NTSC mode exclusively. (25p in 30p is better than the other way around.) But then watching it on PAL only TV would be difficult, or impossible. (Do most PAL TVs have NTSC support?)

In short, there is no real solution for it. You'll have either live with the jitter, or use NTSC mode for everything. If you don't plan to mix up 30p and 25p (or 50i) videos, then you can switch back and forth.

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Answer 6

cybermike Author

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Feb 7, 2009 3:33 AM in response to Euisung Lee

So as i mostly use the Sanyo Xacti which uses 30fps and play back the HD videos mostly on my iMac or my Conceptronic FullHD MediaPlayer (which perfecly streams the H.264 videos even on my old PAL TV - it does the downsampling so i can watch it on the old PAL TV and on for the future it has a HDMI connection) the best would be to keep iMovie with NTSC 30fps settings, right? So this would be the best solution and in the future if i am using an LCD or Plasma TV with an HDMI connector this would be fine, right?

Michael

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Answer 7

Feb 7, 2009 4:04 AM in response to cybermike

Quicktime will play 30fps correctly on a computer screen. When you import into a PAL 25fps movie project you'll get the stutter.

(..Look at trees, posts and other solid objects in the foreground and background of this 25fps movie project ..which contains a mixture of 30fps (Canon SLR, Lumix stills camera, Flip minoHD) and 25fps (Canon and Sony HDV) material; the 30fps fixed objects judder past in stuttery mode.

By comparison; 30fps material slides past nice and smooth, but fixed objects shot at 25fps judder in this 30fps movie of the same original footage; that 25fps material stutters as the camera pans across the scene..)

The same's true for material shot with an Xacti.

So keep everything at 30fps ..that means creating a 30fps (NTSC) iMovie project to import the Xacti material.

You'll then be able to burn the project(s) onto a DVD, by using a 30fps (NTSC) iDVD project, and that should display correctly when played on a DVD player ..even though it's the "wrong" standard for PAL TV; the display adjustment will (should?) be made automatically by the player-and-TV combination.

Most PAL TVs do not correctly display NTSC broadcast or videotaped material (..it may look black-and-white, and have a reduced picture size, etc..) but in your case we're talking about only frame rate (30fps vs 25fps) rather than the encoding-and-display method (..your Xacti probably displays correctly when attached directly to a PAL TV; it's only its frame rate which is at odds with the PAL standard..) and the DVD encoding is fairly NTSC/PAL-method agnostic.

Try with a short - 30 seconds or one minute - test project: import into a 30fps iMovie project; burn via a 30fps iDVD project; play the disc on your DVD player ..if you have one.. or on your Mac.

It's annoying that some cameras shoot only at 30fps (..my Xacti, too; and the Flip mino, most stills cameras which also shoot video, etc).

But short of complex standards conversion, it's simplest to edit their footage exclusively within 30fps projects.

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