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Vladimir Vovk
Vladimir Vovk

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Compress, Convert and Trim Videos with Command Line

#ffmpeg #video #node #cli

ffmpeg

Often, we have videos of different formats and resolutions from our phones and cameras and also from our friends and family. Sometimes, these videos are uncompressed, so they take up a lot of space.

There are many methods how we can solve this problem. But here, I would like to tell you about FFmpeg. It is a free and open-source tool available for all major operating systems. FFmpeg is fast and gives good results in compression, changing formats, and resolution.

To compress our favorite cats.mov video and convert it to mp4 format, we need to run:

ffmpeg -i cats.mov cats.mp4
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Pretty easy, right? The only downside of this command is that ffmpeg does not give us a user-friendly UI. There is no progress bar or estimated time to finish.

ffmpeg

menc

Introducing menc (media encoder), a small "wrapper" utility around ffmpeg which gives a nicer UI and can help to process several files more easily.

To compress the same cats.mov video with menc, we need to run:

npx menc cats.mov
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menc

It will use the mp4 format by default and create a cats.mp4 file in the same folder.

Please ensure you have Node.js installed on your machine.

If you want to extract audio or change resolution it can be done with the --format argument. For example, the following command will compress our video and change the resolution to full HD.

npx menc -f fhd cats.mov
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You can find all supported formats with --help argument:

npx menc --help
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menc --help

To trim a media file, we can use the --start-time and --end-time arguments:

npx menc -s 10 -e 1:09:04 cats.mov
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This command will compress the cats.mov file into cats.mp4 from the 10th second to 1:09:04.

If we want to trim a file without changing format (re-encoding) we can use the --copy argument:

npx menc -e 1:05 --copy cats.mp4
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This command will trim the cats.mp4 (no re-encoding) into a new file from the beginning until 1:05.

To convert several files, we can use the wildcard character. For example, if we have more than one mov file, we can process them all with only one command:

npx menc *.mov
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If we want to write results into a separate my_compressed_mp4_files folder, we can do that with the --dir argument:

npx menc -d my_compressed_mp4_files *.mov
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Custom ffmpeg arguments are also supported. For example, if we need to scale a video file, making the width equal to 320 pixels, keeping the aspect ratio, we can use the --custom argument:

npx menc --custom '-vf scale=320:-2' cats.mp4
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Or, if we want ot set bitrate for output MP3 file to 64k to make it smaller size:

npx menc -c '-b:a 64k' -f mp3 meow.mp3
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Please try menc, give it a star 🌟, and happy hacking! 💻

Credits

Photo by Alan Alves on Unsplash

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