Size of Video

I’m a beginner!
Why is a video much smaller than the original after exporting it after minor changes?
I can’t see any difference in the properties.

Do you mean file size? Digital video is compressed, and there are numerous compression algorithms available, and parameters for each that affect the tradeoff between file size and video quality. Changing the compression algorithm and/or parameters you use for exporting could have a huge impact on file size. That’s probably what’s causing the difference you’re seeing - the algorithm and/or settings you chose for your export are probably different than the algorithm and/or settings that were used for the original.

As an example, I exported a video using the same settings I use for my YouTube videos, but the recipient could not play it because their media player was outdated and didn’t support modern video formats. I re-exported it using an older and less efficient algorithm, with settings I chose to be quite conservative. The file was about 2.5x larger (but looked about the same when watching the video).

Hi and welcome,

You won’t get many replies to a question that vague which is lacking somewhat in important information I’m afraid.

Some questions.

  1. What is your operating system and version of Shotcut?
  2. Do you mean the exported video is a smaller file size, or it is smaller in dimensions (resolution) than the original input video? At this moment I assume the latter.
  3. What is the resolution of the original input video. Is it 1280x720, 1920x1080 or perhaps 4k?
  4. What is your video mode set to?

When exporting, on the export tab tick the advanced box and then look at the resolution of the output video. Those numbers shouldn’t need adjusting but they should also match your input video. If they don’t then you have probably selected the wrong video mode (see above).

That’s probably enough info to get the ball rolling. Good luck!

I mean the file size.
I thought that if you export via File/Export/Video, then the same resolution as the original is automatically used.

There’s a default compression level that’s usually ok. If you don’t see the difference in quality it’s ok with smaller file as it saves space. If you do, you need to change some settings.

Keep in mind that any export from any program will re-compress the video so there is no such thing as exactly the same quality and filesize.

Theres a “extract subclip” feature that just cuts pieces of the original video without re-compression but you can’t add any effects/filters/changes.

The closest you can do to original is to choose an average bitrate mode of the same original codec (x264 probably) and manually fill in the same bitrate as the original video.

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There is also a “lossless” preset option from the left menu that, as explained, isn’t really lossless but it is close. That will also generate extremely large file sizes, possibly much larger than the original, especially if you used a phone for the recording.

Pesonally I have always found CRF 15 (67%) to be a good compromise; visually very close to lossless while also being a reasonable size. Those settings can be changed in the export tab. Tick advanced and then go to the codec tab and adjust accordingly.