iMovie export quality vs. Quicktime's save-as-self-contained

[Direwolf]

I've tried various settings using iMovie 4's Share function, including:

Full Quality DV
Expert Setting's Movie to DV Stream
Expert Setting's Movie to QT using DV/DVCPRO-NTSC

Then I tried opening the .mov file (from the iMovie project folder) in Quicktime, and saved it as a self-contained movie...

RESULT: the self-contained movie produced a higher quality video.



I need to move this movie to another mac to encode/burn to DVD, so I want to preserve as much quality as possible before encoding.

So I have 2 questions:

1. Why are the export options in iMovie of lower quality than Quicktime's?

2. Will I be able to transfer this .mov (the self-contained movie) into iDVD 3.0.1 for encoding/burning?

Thanks.

[WiseWeasel]

Do NOT use the Full Quality DV option, as it's not full quality at all, and the audio is downsampled to 32 kHz (DVDs require 48 kHz). Expert Settings: Movie to DV Stream and Expert Settings: Movie, self-contained preserve the full quality. For some reason, Expert Settings: Movie, self-contained is larger filesize, and preserves the volume track, and is the option I use, with good results. Either of those two should be fine, as long as you stay far away from Full Quality DV. It's incredibly stupid of Apple to have named that option as such, since it's clearly not full quality, and misleads people into losing quality.

[terryj]

Your other option for Full Quality video is to drag and drop the iMovie
reference movie into Compressor, and export to Quicktime as
Self Contained movie using the 3ivx d4.5 codec at ,
Single Pass - Constant Quality (CQ), set to QP2 with audio set
to 48khz audio, 16bit, 2 channel stereo.

http://www.3ivx.com/support/mac/encoding/quicktime.html
This will produce a very HQ file, near lossless, from which you can reuse
in various ways ( creating a MPG-1, Real Media Export, etc.)
later on.

[WiseWeasel]

That's not lossless at all. Stick with DV if you're outputting to DVD, so you don't needlessly lose quality along the way with extra compression like 3ivx.

[Direwolf]

Just wondering about the Expert Settings:quicktime to dv stream output ... if this IS lossless, why does does this seem more pixelated and lower quality vs. the self-contained .mov file?

[Thargok]

Just wondering about the Expert Settings:quicktime to dv stream output ... if this IS lossless, why does does this seem more pixelated and lower quality vs. the self-contained .mov file?

The Self-contained movie is the original footage in a QT container.
The Export is a recreation of the original footage into a different file.

So pretty much it is like this, the first one is an apple that you put in a bag.
The second one is an apple that is cut in half and then put back together and then in the bag.

Sure, they are very similar; but the first one is preserved better.

[MerlinMacuser]

You guys are awesome!

[terryj]

That's not lossless at all. Stick with DV if you're outputting to DVD, so you don't needlessly lose quality along the way with extra compression like 3ivx.

ummm, I beg to differ, in fact that's why I said to use the Q2 setting.
The Q2 setting is primarily used to Archive footage
at lossless/ near lossless capacity, with only minor compression.

In a test that I have done on a 2:15:36 sec video,
export to DV yeilded a 12.2 GB file. The same file
archived to QT MOv using the Q2 setting in 3ivx setting
produced a QT mov that was 9.7 GB and retained very HQ,
identical to the DV stream.

In comparing say a Photo save as a .JPG, Much like a JPEG,
if you use Higher Quality, lowest Compression,
you will get a file that is not as large as the DV stream,
but that contains very High Quality, and maintains it through
"conversion" to other types, such as MPEG-2, MPEG-1, or
MPEG-4.

try it out for yourself and see....

[Direwolf]

Unfortunately, I have a G3/300 and can't use Compressor ... that's why I need to transfer the file to a G4 for encoding and burning ... which brings me back to my original #2 question:

Can I drag this self-contained .mov into iDVD 3 for encoding/burning?

[WiseWeasel]

If it's DV, then yes. Not sure about 3ivx. Regardless, if you can preserve the original streams, it would be better. Recompressing in 3ivx format or whatever is NECESSARILY going to introduce artifacts and lose quality. That's why Expert Settings: Movie, self-contained is the best option for what you want to do, without losing ANY quality whatsoever. Even if you have quality at 100%, there is still recompression going on, and so you will lose quality. A good analogy is if you take a screenshot of a jpg image. When compared side-by-side at the same size, they will look identical, but if you try to resize them or perform any manipulations, the screenshot will be much lower quality, since you're losing a lot of the data. Resampling will lose quality, and should always be avoided. Saving as Movie, self-contained doesn't resample, but merely copies the original video and audio streams to a new container, unchanged. This is by far the best way to move the data from one computer to another without losing quality.

[terryj]

Can I drag this self-contained .mov into iDVD 3 for encoding/burning?

Yes, even if you are using the QT PRO 6 option of
Export: Movie to QT Movie, which i do,
without using the Quicktime
default Video codec, which produces crap,
and are using the 3ivx codec
with Q2 option as I stated.

You can use the option to Save from iMovie as Self Contained movie,
and yes this will produce great quality video, albiet at the highest
file format size. The option I stated, from iMovie, Export to QT,
then movie to QT movie, setting the codec to 3ivx Q2, will
create a file with MINISCULE compression, but at the highest
Quality, and might be easier to transfer to another mac, depending on
how much and how you are transferring it, to answer your original query:

I need to move this movie to another mac to encode burn to DVD

The file will be recognized by iDVD4 as a QT Movie,
because that is what it is,
and will do its normal format and burn in its stages.
3ivx D 4.51 is a CODEC, not a FILE TYPE.
SORENSON, 3ivx D 4.51, and Targa are codecs,
.mov, mpeg, .avi, and .wmv are file types.


True, resampling will produce lower results, but
since you are going from original DV (source) to new container
( final output), NOT going from a already compressed format
( such as MPEG-1 or MPEG-2 to QT movie with codec),
there WILL BE Miminal Compression, but Q2 is a near lossless codec
( like within 3% loss.) Much like comparing a PSD file to a LZW compressed TIFF. While the PSD (DV Stream) is most preferable,
the TIFF does have some loss, but when compared in quality to
the PSD, side by side, they are identical, yet the TIFF with LZW compression makes for a smaller foot and therefore in some instances
might be better where there is less disc space. Understand?


But yes, overall, if you could transfer the original streams, say via FW drive, that would be your best option.

[WiseWeasel]

BTW, DV is a compressed format. There is already compression done by the camera to make the video fit in 25 Mbps. Uncompressed video is much bigger than that. To go from one compressed format to another will lose a lot of quality during resampling, as different codec formats and encoders will save different data. Even if you resample from DV to DV, the quality will go down as different encoders work differently. Saving the original streams is the way to go if you're worried about losing quality.

[Direwolf]

Awesome,

Thanks for your prompt and informative responses, WW and TJ.

[terryj]

Your welcome, Dire!

[sdm]

Much like comparing a PSD file to a LZW compressed TIFF. While the PSD (DV Stream) is most preferable,
the TIFF does have some loss, but when compared in quality to
the PSD, side by side, they are identical, yet the TIFF with LZW compression makes for a smaller foot and therefore in some instances
might be better where there is less disc space. Understand?

sorry that this has nothing to do with video output,
but a .tiff file with lzw compression is lossless.
here is a link that explains lzw compression:
http://www.catenary.com/appnotes/lzwcomp.html