Compress mp4 using FFMPEG

ffmpeg-compress-mp4

$ ffmpeg -i input.mp4 -vcodec h264 -acodec mp2 output.mp4

ligantx experiment is the most efficient (tested on macOS), 700k for bitrate seems to be a good measure for maintaining quality while lowering file size:

ffmpeg -i input.mp4 -vcodec h264 -b:v 700k -acodec mp3 output.mp4

i'm gonna add some notes here

1. in the time of writing this (jan 2023) you don't need to specify h264 as the video codec in ffmpeg when the output is mp4 since that's the default codec
2. for audio it's better to specify the bitrate rather than the codec, 96Kb is good enough -b:a 96k
3. not all videos will look good with a video bitrate of 700kb it depends on the resolution, the original codec used and whether there's a lot of movement / particles

I'd recommend that you first let ffmpeg compress it automatically without any arguments ffmpeg -i input.ext output.mp4

• if the output is not enough then use 2/3 of the original video bitrate with -b:v and keep lowering until you reach a desired size
• you can lower the resolution with -vf scale=1280:720
• if you only want to save your video on your pc then use the new mp4 codec 265 -c:v libx265, it has better compression, and just ike 264, nearly lossless. the issue with this is that it's still not widely adapted and sites like discord can't play it

Commands using Linux with ffmpeg to shrinking big MP4 video file to smaller sizes

• ffmpeg -i input.mp4 -vcodec h264 -acodec mp2 out.mp4
• • 3.6 Gb to 556 Mb, great quality 🥇
• ffmpeg -i input.mp4 -s 1280x720 -acodec copy -y output.mp4
• • 3.6 Gb to 62 Mb, quality "good enough"/acceptable 👍
• ffmpeg -i input.mp4 -vcodec h264 -b:v 1000k -acodec mp3 output.mp4
• • 3.6 Gb to 30 Mb, very shitty quality 💩

good enough worked fine for me..To my "average human" eye, i coudlnt find any real difference with the original video compared side by side (original: 1gb to good enough: 296mb)

Edit: if you wanna go lower try changinng -b:v value e.g.: ffmpeg -i input.mp4 -vcodec h264 -b:v 700k -acodec mp3 output.mp4 and if you don't want sound try: ffmpeg -i input.mp4 -vcodec h264 -b:v 700k -an output.mp4

My experiment:

• ffmpeg -i input.mp4 -vcodec h264 -b:v 1000k -an output.mp4
  32MB to 3.6MB
• ffmpeg -i input.mp4 -vcodec h264 -b:v 200k -an output.mp4
  32MB to 742KB

thanks, it works.
using || -b:v 1000K || ---- from 2MB to 1MB mp4 file

./ffmpeg -i input.mp4 -c:v libx265 -preset ultrafast -crf 28 -c:a aac -b:a 250k output.mp4

This is better for h265, it's fast and should reduce the file size by 50-70% if you want better video, change the ultrafast to fast or change the -crf to a lower number like 24

If you want to change from 4K to 1080P, add -s 1920x1080 after the -i input.mp4

./ffmpeg -i input.mp4 -c:v libx265 -preset ultrafast -crf 28 -c:a aac -b:a 250k output.mp4

This is better for h265, it's fast and should reduce the file size by 50-70% if you want better video, change the ultrafast to fast or change the -crf to a lower number like 24

If you want to change from 4K to 1080P, add -s 1920x1080 after the -i input.mp4

This worked pretty well for me -- converted a 323 MB Zoom recording to a 81 MB file. without reducing resolution, is there anything more one can do to further shave off the file size?

Commands using Linux with ffmpeg to shrinking big MP4 video file to smaller sizes

• ffmpeg -i input.mp4 -vcodec h264 -acodec mp2 out.mp4
• • 3.6 Gb to 556 Mb, great quality 🥇
• ffmpeg -i input.mp4 -s 1280x720 -acodec copy -y output.mp4
• • 3.6 Gb to 62 Mb, quality "good enough"/acceptable 👍
• ffmpeg -i input.mp4 -vcodec h264 -b:v 1000k -acodec mp3 output.mp4
• • 3.6 Gb to 30 Mb, very shitty quality 💩

Thanks for sharing, really helpful!

None of these have done anything, but give me a 30-35% INCREASE in size. I'm still determined to find a solution but attempts to compress this video by ANY means results in similar results.....

@AD5GB as i said before here, it depends on what video you have, so you need to experiment a bit

A DCV file is a special encrypted format used by the video-sharing site and download service provided by DMM.com.

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However, DCV files cannot be played using anything other than dedicated players or download software; thus, they need to be converted to the MP4 format.

Converting DMM video DCV files to MP4 requires the use of dedicated software, many of which are available free of charge.

In this article, we will guide you on how to convert DMM video DCV files to MP4.
https://sothinkmedia.com/ja/convert-dmm-dcv-files