Hi folks. I'm pretty new to using iMovie or any video editing software. I just have a few MP4 files that I want to cut up into separate MP4 files and learn a little iMovie while i'm at it. Is there a walkthrough somewhere that would show me how to do that? Also, I want to be able to export without any compression of any kind. It seems that every program I try out wants to compress everything. Thanks.
iMac, macOS High Sierra (10.13.5)
Yes, I understand. I was trying to find a way to convert the audio codec to a lossless format and hook it back up with the video, and export that out. But it appears that if you export it out at any quality setting than Best Quality (pro res) iMovie will convert the audio codec to AAC (lossy format) on export.
I think that your best bet is to put your Mp4's into iMovie and export them out at Best Qualty (pro res). That will give you a .mov file (rather than an Mp4 file) with the most uncompressed video (albeit 4x file size). It will also give you the LPCM (Linear Pulse Code Modulation) audio codec, that is an uncompressed codec so thus lossless. If you export out any any other quality setting you will get an Mp4/AAC format, and the AAC audio codec is lossy.
So, the better quality with less compressed or no compressed is a trade off with a much larger file size.
-- Rich
Hi,
Assuming that you are using iMovie 10: Place your clips into the timeline of an iMovie project. Click on a clip to select it. Then do Modify/Split Clip.
Here's a link to an online Help menu that will explain the various features of iMovie 10.
https://help.apple.com/imovie/mac/10.1/#/mov16b2ea79a
There are no consumer video editing products that will let you export with no compression. To do that you would need a pro setup like they have in TV stations. In iMovie you can export with Best Quality (pro res) and Better Quality compression. You will get a 4x larger file size, however.
-- Rich
Thanks for the reply Rich. I find what you're saying to be true but that seems odd to me. Why would you want to compress and already compressed file any further? Why can't these products just cut the file down without compression? I hate compression and like better video quality 🙂 I find it strange that everyone is just okay with their video to continue to deteriorate as you work with it. I mean it's digital, it's not like we're still in the VHS era! I wish there was something that could just chop up an MP4 file into smaller MP4 files. That's crazy.
Rerendering will always leave something on the table, but usually not visible to the human eye unless one does a frame by frame analysis--and maybe not even then. For consumers it's not practical to be working with totally uncompressed files. Equipment is expensive. Files are massive. Stoage unwieldly. Difficult to share on internet and to other devices. And most people don't display their movies on movie theater sized screens.
The least compression you will get is right out of the camera. So keep your master file intact.
-- Rich
Thanks Rich. What i'm doing is ripping some of my old Music DVDs to MP4 and would like to split out some of the songs and have each song have it's own file. Given that it's music stuff, I'd like the audio to remain as closely as master as possible. The video is a tad less important but I'm a video quality nut so I don't want that too compressed either!
Thanks Rich. I think I"m willing to sacrifice a little a/v quality but I don't want to compress it a ton. Unfortunately I'm one of the guys that would rather have a large file and good quality than the opposite. These are DVDs anyway so not that big to begin with. I appreciate your detailed responses. I will play around with it and see what works best. Much appreciated!
EDIT: Just to be clear, I mean like my concert DVDs from different music artists. Not audio files on a DVD.
You are welcome. 🙂
-- Rich
How to split MP4 file into smaller MP4 files?
