File size doubles

Sorry for dumb question, but: I open a mp4, crop it, and export it and the new file size is almost double the old. Why is that? I didn’t change anything else. How can I reduce the file size.

Original file specifications? (Source Tab, then Properties Tab)

  • Resolution
  • Frame Rate

Video Mode? (Settings/Video Mode)
Export Settings (Video & Codec tabs)

  • Resolution
  • Frames/Sec
  • Export preset used?

When you say “crop” do you mean using the Crop Filter?

The file is re-compressed/-encoded using a fairly high quality. I assume by “crop” you mean the Crop video filer. Any type of operation that involves modifying the image must be re-encoded. Any re-encoding that is not using lossless encoding loses a little bit of quality in the process. Therefore, the re-encoding should try to re-encode with less compression (more compression generally implies less quality) than the original.

Trimming a video by changing is start or ending time is not cropping; it is called trimming. If that is what you want, but you do not want to re-encode, then you should use Properties > menu [button > Extract Sub-clip… however that is not typically frame accurate due to something called temporal compression in the original file: It’s complicated.

This topic was automatically closed after 90 days. New replies are no longer allowed.