KB1071 - Video Size, Resolution, and Performance

Selecting the optimum resolution for your video project can be a bit tricky. Manufacturers all promote the sharpness and size of their video displays on computers, mobile devices, and televisions, but that's because they're trying to get you to buy a new tablet or TV!

It's one thing to enjoy those qualities as a consumer, but it's different if you're the creator of a video and must decide which resolution is best for your project and audience.

How much resolution do you and your audience really need?

Image comparing different sizes of image resolution
Video resolutions (VCD to 4K). (Wikimedia Commons)

If the word resolution is unfamiliar to you, then please read on:

  • 720p refers to HD video at 1280x720 resolution - 720 lines high.
  • 1080p is video at 1920x1080 resolution.
  • 4K video is approx 4000 x 2100

You can see the difference between these resolutions in the diagram: 4K video is four times the resolution of 1080p video (double the width x double the height), resulting in a file size that’s four times bigger overall.

So, if you were to record a video at 720p and the file size was 5 Gb, the same video recorded in full HD (1080P) might be 20 Gb, and if it were recorded in 4K resolution, it might be up to 80 Gb. The difference between using 720p and 4K is a factor of 16 times!

So, for your web-based video project, how much detail and data do you really need to deliver your story effectively?

When to shoot in 4K

Almost never, unless your classroom or technical demo video will be shown on a giant video screen, or if it requires vast amounts of detail, like you'd see in an epic movie battle scene or in a team sport where you’re viewing the players from 100 yards away and still want to read the numbers on each player's jersey.

When to shoot in 1080p

Try 1080p if you’ve tried 720p and found that the quality just isn’t good enough, or some detail is too soft for the subject you’re recording. (Of course, maybe you really want one of those cool high-res, high-speed chopping shots like on the cooking channel, where the carrot slices are flying off the knife in slow motion. Go for it, but you may pay a price in extra time and effort to edit, render, and upload that slick footage in 1080p at 60fps…)

When to shoot in 720p

If the subject you’re shooting is only a few feet away, such as a workbench demo of your hands working right in front of you or a head-and-shoulders “talking head” shot to introduce a course or new lesson. Try 720P first, and if you’re happy with the quality on the largest display your audience will use, then you’re good to go.

Basically, memory and storage may be relatively cheap these days, but your time is not and neither is your audience’s.

Think about these factors:

1.     How large are the screens your audience will use? Are we talking about laptops, or tablets, or even smartphones? The less data they need to download, the faster those first frames will start playing.

2.     How fast can your audience download video? Is your audience using a wired or wireless connection? It’s prudent to assume slow connections, or old computers with poor graphics cards or low memory.

3.     How much extra time do you as the creator want to spend waiting to edit, preview, and upload a video file that’s in the dozens of Gigabytes, versus a file that’s 10-100X smaller? The more data your upload to your video host, the longer it will take to process and prepare.

IMPORTANT: Issues with Storing Large Video Files in Kaltura

Kaltura converts 4K to 1080p

VCC uses the Kaltura platform for audio and video media management. Kaltura will allow you to upload 4K video content, but when Kaltura transcodes the video into multiple playback "flavours" (to deliver the most optimal resolution for different situations), the highest available flavour Kaltura will provide for playback is 1080p. So any 4K video you upload to Kaltura will be converted to 1080p and lower resolutions.

The only potential limitation to uploading 4k videos would be file size. While technically you should be able to upload a 20 Gb file, multiple users simultaneously uploading files of this size to their Kaltura folders could cause systems delays. Generally, a maximum video file size of 3 to 5 Gb is preferable.

Kaltura supports Panoramic, 360 degree video

Katura's video players automatically detect and support 360 degree panoramic video. If you have a webcam or action cam that saves panoramic video, just upload it to Kaltura and embed it into your course like any other video format. When your viewers watch it in the Kaltura player, they'll be able to pan around in your video in all directions.


Article ID: 688
Wed 7/15/20 10:10 AM
Thu 8/10/23 1:48 PM

Related Services / Offerings (2)

Issues with overall Moodle responsiveness, or system-wide problems.
Reducing the storage impact of Moodle course by compressing or removing data.