Importing a GoPro HD Hero 158 Gb

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Level 1

8 points

Importing a GoPro HD Hero 158 Gb

Good day everybody,

As an ultra trailer, I have prepared the Ultra Tour du Mont Blanc race last July, by running the whole track in 5 steps, filming each second of this training. I put the MP4 files on a external drive, which takes about 158 Gb of disk space.

I decided to import them into iMovie, using another external drive (1 Tb), with more then 750 Gb of free space.

When finished, the whole result takes 556,5 Gb, so, almost four times space. The result is mov files + thumbnails.

Is it normal to use so much space or is it a way to reduce it, without loosing quality?

Thank you

iMac 24", Mac OS X (10.6.3), 2.8 GHz Intel Core Duo 4 Gb 667 SDRAM 1 Tb HD

Posted on Aug 20, 2011 3:37 AM

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Answer 1

Best reply

elikness

Level 4

2,640 points

Aug 20, 2011 8:18 AM in response to Looping

If your footage is HD compressed into .mp4 format, iMovie needs to decompress the video frames in order to do ANYTHING with it. According to Apple's rule of thumb HD footage will be roughly 40GB per hour when it's brought into iMovie. By this estimate you would have shot very close to 14 hours of raw unedited video.

The Standard Def video takes roughly 13GB/hr. of video footage. HD's physical size height and width is roughly 4 times (4x) the size of a Standard Def video frame. It adds up very quickly when you are doing HD unfortunately. iMovie won't really let you edit the video in anything other than the high rez big version if you intend to output at the same High Def resolution. Final Cut Pro X will let you edit at a lower rez (it's a proxy for your high rez footage) and then let you out put to the higher rez using your raw video footage as the final video source. But that requires having to buy and learn how to use that feature in Final Cut Pro.

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Answer 2

Looping Author

Level 1

8 points

Aug 21, 2011 7:14 AM in response to elikness

I think you are right. I noticed that I have to multiply the original size by almost 5 (4.83) to get the final size (.mov + thumbnails).

Thank you.

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Answer 3

elikness

Level 4

2,640 points

Aug 21, 2011 8:15 AM in response to Looping

No problem, that multiplier effect isn't widely advertised until you read through some of Apple's iMovie information. And if they put it near the top, where it was easy to find, I think people would get a clearer idea of how to manage their Event clips. You were well prepared with the extra storage, but a lot of people fill up their internal hard drives and come to the Discussion Board desperate to move their files and keep their Mac from crashing. Good Luck.

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