Have you exported a video in QuickTime and confused with the output size of it? Well, let us look at a scenario and see how to solve this problem.

“I took an MP4 original file with a resolution of 720p, trimmed it and saved it (Command-S) without making any adjustments to the size. The result: 88.8MB. That was close to what I expected, but the file was still way too big to use on the web. How do I control the size of the video after exporting on Mac?”

Trimming a video in QT Player and saving will preserve the trimmed movie file, but scripts the points to play.  When you play saved video file in a media player like VLC or other non-Apple media players, you will not see trim marks as they ignore them.

Apparently, using ‘Save As’ options lets you to save a damaged copy wherein the trimmed parts are removed. But the important issue here is the import option. In the above query, a low-resolution movie was chosen and got a high-resolution file after exporting it. This looks unreasonable, but it derived from how movies are stored, played and exported.

The video is compressed universally. In compression mode, the algorithm scans sections of an image or both sections of frames and dissimilarities between frames in a movie to find approximations or patterns. If a big area of a frame or image is comparatively the same green, with a high-level of compression, it turns into all green and occupies small bytes to store. The higher reliability you need, the more t motion and tonal variations are well-kept, and the larger the file.

When QT Player and other tool play back a movie, the compression is decoded, and latest Mac and iOS (and other makers’) devices have in-built chips that takes care of the de-compression for real time playback, instead of controlling it in software. Nevertheless, when a clip is exported, the software will decode and again re-encode it. That decoding brings back the original frames though they were un-compressed, and then implements the new export options. In simple terms, it is called as Transcoding – where you convert one format to another.

The earlier builds of QuickTime, particularly QuickTime 7 Pro, and earlier builds of iMovie allowed you explore settings much more. This allows you play with knobs to make a higher compression and resolution ratio according to your needs.

Note: If by any chance you end up making the video corrupt, you can opt for HD Video Repair Tool for Mac to fix the issue and make them play again.

VLC which is open source and free is an exception. It has few video transcoding types but needs a lot of proficiency. Contrasting to Apple’s products, VLC has infinite dials to play with.

It is recommended to use File and then select Convert & Stream for a simple and easy approach for an identical resolution output. If the pop-up options trick doesn’t work, you still have an option, go to Customize button beside the pop-up tab. You will need to dedicate a quality time to study on how to adjust the levers for the optimum results. After you’ve figured it out, rest is a cakewalk for you.

An Ending Note:

With little understanding of Settings on how to import video files in QuickTime and other media players, managing the size of exported videos shouldn’t be a problem. Hope this article was a help in resolving the issue.