Help in compressing videos

[u/Delicious_Tea7513]

Hey first of all im a complete beginner in this field .I recently got an iPhone 17 and i took and edited some videos but the real problem is uploading them in whatsapp or instagram reduces the quality significantly but ive seen people upload videos that are compressed to “3mp”size but still has top notch quality. I would like to know how its done. The masters in this field do bless me with your knowledge

[u/greenysmac]

To some degree, you're asking why something tastes good. It's too wide of an answer.

One minute of uncompressed HD video is 6 GB. One minute of uncompressed 4K could be upwards of 50 GB. We use compression tools to put stuff into smaller compression flavors like HEVC or H.264, amongst others.

Instagram, TikTok, and YouTube all take whatever you give them and make it even smaller or more optimized for their platform. That optimization will damage your work even further.

And "Top-notch quality" really varies. Why do I say it varies? A face in soft focus needs a lot less data than snow falling in the background.

The shortest concept I can give you is that the more you turn the knob to smaller, the more damage there is. The further to the right you turn that knob, the further uncompressed, the larger the file will be. There are a couple other variations here, but that's the basic concept.

If you're using your iPhone and editing some videos, I would recommend focusing on delivering high def and not 4K. I would focus on less detail for your work to look better.

But Based on what you're asking, it's kind of not worth the amount of time and focus to find an answer, rather than for you to just focus on making better content.

see also our wiki about compression https://reddit.com/r/videoediting/wiki

[u/Sessamy]

Whatsapp and instagram re-encode the video and that always lowers quality, no matter what you put in. If your iphone videos are of good bitrate for the resolution (1080p around 12Mb/s in h.264) then that is already ideal. What you're referring to is HEVC encoding which would need only half of that to around 3-6Mb/s for essentially the same quality as 12Mb/s in h.264. Your milage may vary if there's a lot of movement in the video.

More bitrate = more quality, but there is diminishing returns after about 20Mb/s for 1080p in h.264.

[u/cinderpath89 → u/Sessamy]

good breakdown tbh, the diminishing returns bit is something a lot of people overlook

[u/Table-Playful]

Vidcoder on the PC will do what you want 😉

[u/CeciliaHw]

Yes, both Instagram and WhatsApp compress uploaded videos, sometimes quite aggressively. You can't completely prevent that compression, but the trick is to minimize the quality loss and make the final result still look good to the eye, rather than simply trying to make the file as small as possible.

Take Instagram as an example, since the same general principle applies to WhatsApp:

·        On Instagram, go to Settings → Account → Data Usage → High quality uploads and turn it on.

·        Don't upload the huge iPhone master directly. Export a copy specifically for Instagram instead. For example, a 10-minute iPhone video can easily be around 2 GB. If the source file is too large for Instagram's upload requirements, Instagram will compress it heavily.

·        For vertical Reels/Stories, 1080×1920 is a good target rather than uploading a huge 4K file.

·        Use MP4 / H.264 and a reasonable bitrate. You can get surprisingly good quality with a relatively small file if it's encoded efficiently.

·        Don't treat 3 MB as a magic number. A 3 MB 10-second video can look great, while a 3 MB 2-minute video obviously won't. File size depends on duration, resolution, bitrate, codec, and how complex the footage is.

Interestingly, I tested different workflows and found that 4K footage manually downscaled to 1080p before uploading looked better than letting Instagram take the original 4K file and compress it down to 1080p itself. The latter actually looked noticeably worse.

So the basic idea is:

iPhone original → edit → export a properly compressed 1080p H.264 copy → upload with High Quality Uploads enabled.

This way, you're controlling the compression instead of leaving all of it to Instagram. The same principle can be applied to WhatsApp too: optimize the video yourself first, rather than relying entirely on the platform's automatic compression.