quick question about imovie (only answer if you're 100% sure)

Pelea

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Oct 5, 2014
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if i take a 1080p video on my iphone and then use imovie to cut out sections of the video in the middle, before exporting the video, will i lose quality when exporting the 1080p video as 1080p?

so basically, is using imovie to export iphone videos lossless or not?

i tested out my original video + an edited one and i think i see a slight degradation in quality, though i'm not 100% sure. (i compared the 2 videos frame to frame)
 

Pelea

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it took an hour but i zoomed in on a leaf in both videos (same frame) and did indeed notice a small decrease in quality. so it's not lossless. does anyone know of any lossless ios video editing apps?
 

bopajuice

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Mar 22, 2016
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Dark side of the moon
This question could be answered by the FCP crowd.

When I export a movie from my phone to the computer the info tells me it is a h.264, 1920x1080 video, with a data rate of 25.09 bits/s. I have the phone set at 1080 60P. I can edit it and keep those settings. Technically it's not a "lossless" issue. I know iMovie has options to export for phone, mail, iTV, etc., but every one of those settings will compress the video to make it suitable for that device. What export settings are you using? That is most likely the issue.

When you render a movie and export it needs to be kept as the original. FCP gives you that option, but not sure about iMovie. Sorry I can't give you a 100% answer. I don't have iMovie on my computer so I can't check the export settings available.
 

atlas_0

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Dec 30, 2016
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it took an hour but i zoomed in on a leaf in both videos (same frame) and did indeed notice a small decrease in quality. so it's not lossless. does anyone know of any lossless ios video editing apps?
If it took you a freaking hour to spot such a minor difference in quality, what exactly are you on about? If you export it over and over again, sure - might be an issue. But we're talking about an iPhone video here, with quality loss so minimal that it took you literally an hour to even spot.
 
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Atomic Walrus

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The original video is in a lossy compression format.

When it is edited and exported, it must be re-encoded, again in a lossy compression format. There will be new data loss in this second round of compression.

There may be utilities that let you do simple clipping without re-encoding, but you'll have to do some research (try googling something like "h 264 editor without re-encoding").

Whether or not the effect is noticeable is dependent on the bitrates involved.
 

Pelea

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If it took you a freaking hour to spot such a minor difference in quality, what exactly are you on about? If you export it over and over again, sure - might be an issue. But we're talking about an iPhone video here, with quality loss so minimal that it took you literally an hour to even spot.
actually i saw the difference between both videos instantly when watching both of them at the same time. one looked blurrier than the other. i simply couldn't prove it until i zoomed in on a specific part of a video which clearly showed the difference. so for content creators imovie is a definite no if you care about quality.
 

atlas_0

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Dec 30, 2016
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actually i saw the difference between both videos instantly when watching both of them at the same time. one looked blurrier than the other. i simply couldn't prove it until i zoomed in on a specific part of a video which clearly showed the difference. so for content creators imovie is a definite no if you care about quality.
If the difference was that drastic it wouldn't have taken you so long to "prove" it.

It's an iPhone video. This isn't some masterpiece shot in pristine 4K on a multi-thousand dollar camera, going into pro software. Getting your panties in a wad over degradation that took you an hour to prove existed is a waste of your time. If what you want is flawless video quality, get the tools that'll deliver that rather than polishing a comparative turd by using an iOS device and mobile iMovie.
 
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