How can I output unrecompressed DV from iMovie?

October 1, 2006 6:20 PM

How can I export DV from iMovie without it being recompressed and pixelated? And no - DV stream isn't doing it.

It's not as simple a question as I make it sound - I've tried exporting my DV sequence in almost every format at various levels of quality, including uncompressed with 10-bit color, but every time I export it, it never looks as good as it does in the preview in iMovie. In the editing window, the video is sharper and shows no interlacing artifacts, but no matter how I output the movie (I've tried through FCP and Compressor as well), even as a supposedly unmodified DV stream, it loses detail and becomes pixelated. I also output a DV stream and put it back into iMovie to make sure it wasn't just an iMovie viewing thing, but it looks different in iMovie too once it's been exported. I'm climbing the walls here! I just want it to take the DV info and put it out unmodified but cut and sequenced as I have it in the project - no recompression necessary or desired.

posted by BlackLeotardFront to technology (8 comments total)

Did you try share->quicktime->expert settings->video and then choose "none" in the compression pop up list?
posted by chococat at 6:26 PM on October 1, 2006

That actually creates a pretty good video, I think I tried raw AVI but not raw MOV. But... the interlacing is super obvious and the 8 second test clip I rendered came to 210MB. Thanks for the tip, I can probably use that, but there has to be a way to output unrecompressed DV...

In any case if I can fit the thing on my hard drive at those settings I might be able to put a decent deinterlace on it in After Effects or something.
posted by BlackLeotardFront at 6:44 PM on October 1, 2006

yes, uncompressed video is definitely a PIG.
excuse me if i'm not understanding you right, but did you try exporting as DV-NTSC?
in that same "expert settings" window, you can choose video and then choose DV/DVCPRO-NTSC...you can choose interlaced or progressive, also...and make a way smaller file.
posted by chococat at 7:35 PM on October 1, 2006

To get at the raw DV data, just drag the clip to the desktop, from either the clip library or the timeline strip. No recompression is done. Realize that the data off a DV tape is at around 36 Mbps or 1 GB per 4 minutes.

What is your target application? DVD quality is MPEG-2 encoding at about 6 Mbps. The best quality low-bitrate codec h.264, which can get DVD quality at about 1 Mbps.
posted by todbot at 7:56 PM on October 1, 2006

Chococat -
I've definitely tried exporting as DV-NTSC, but it recompresses it. The DV stream doesn't look BAD, but it isn't what I'm seeing in the preview. So far it looks as if uncompressed is going to be the only way... Whatever, DVDs are cheap, I can split it and burn it. Should be about 20 gigs... rarrgh

Todbot, I'm not just doing one clip, it's a whole composition, about 13 minutes long. The total DV footage making it up is about 9 gigs - and that's my target size. I'm looking to archive it without any loss to the video quality... I'll be putting it on DVD too, but I'd like an original copy as well that's higher fidelity.
posted by BlackLeotardFront at 8:26 PM on October 1, 2006

Why not just archive it back to tape?
posted by strangeleftydoublethink at 8:54 PM on October 1, 2006

The preview is significantly different (one field) in iMovie.

When you export as Quicktime, Compress for Full quality, it's not adding/removing any compression at all.

It's copying the DV data from seperate files into a single Quicktime container as DV (identical) data.

DV consumes at approx 5 min to the gig. So if it's 9 gigs, that's a bit bigger than it should be. Uncompressed 10 bit ought to be about 1.2 gig to the min or so.

You can't truly use QT to determine quality - most programs that output to quicktime in DV, don't use the high quality flag, as it slows playback.
posted by filmgeek at 10:55 PM on October 1, 2006

to elaborate what filmgeek said -- open your exported DV mov in Quicktime Player. Open movie properties (i think you might need to have Pro) and buried in one of the "Video" stream options is a quality flag. If you set it to "High Quality" then it should look like what you see in iMovie.
posted by kamelhoecker at 7:38 PM on November 30, 2006