100mb video=1gb or more in iMovie and iDVD!??

[AlmightyG5]

I have 10, 100mb video files that i converted from .avi to .mov with ffmpegX. The files size stayed the same give or take a couple megabytes after the conversion. I put these ten files into iMovie witch should equal around 1gb. 100mb x 10=1000mb. But after i saved the iMovie and looked at it's file size it said the poject was 22gb!!! Also when i put one of the files in iDVD which should be around 100mb out of 4gb of space...the one video file took up a gb of space.

Does anyone know whats going on here?

 

[zim]

Most likely what you are seeing is that iMovie has converted the files to DV format. DV has a much larger file size.

That is my best answer... too hot to think.

 

[yellow]

Yes. Digital video, such as you have in iMovie and iDVD, are barely compressed. Therefore, what you have in a very compressed .avi and a very compressed .mov are suddenly huge in size as all compression is lost (sadly without gain in quality).

Unfortunately, I cannot find the ratio of video time to approximate size on the disk at the moment.

EDIT: Found it (thanks Wintermute!)

https://forums.macrumors.com/showpost.php?p=1529056

Rule of thumb is 4 mins of DV stream footage = 1Gb.

 

[AlmightyG5]

so is there a way to make the video import to mpeg2 or some other compression so the files are 100mb like they should be?

 

[AlmightyG5]

anyone?

 

[yellow]

As far as I know, no. A DVD's video is DV, and therefore, uncompressed. But I'm not a video engineer, so you should wait for one of those.

 

[stoid]

As far as I know, no. A DVD's video is DV, and therefore, uncompressed. But I'm not a video engineer, so you should wait for one of those.

DVDs are encoded in MPEG2. Otherwise to fit a 2 hour movie the disc would have to hold about 25GB. As far as I know, there is no way to get iDVD or iMovie to use MPEG2 instead of DV streams.

 

[bootedbear]

iDVD will take the input DV and convert it to MPEG-2 using one of two schemes (called 'best performance", a single pass encoding, or "best quality", dual-pass encoding). So the size of the input files are really rather moot. What really matters is run-length.