Making Videos Smaller
Firstly, do you really need a video? They’re big, and can compromise students’ data allowances on their home internet and be slow to download.
Maybe a page with annotated still would be better?
But there is always the more personal touch that videos give, like a “good morning” greeting to your students, or a HowTo that you want to give them, so here's:
- How to record your Mac screen, or part of it, as a movie in Quicktime
- How to record your iPad/iPhone screen
- How to record your screen in WIndows 10
But then, you have very little control over the size of the video file, and these can be really big. So, how do you compress videos to make the file size smaller?
You could:
- look at the camera on your phone or tablet and change the resolution of the video that it will take. Basically, the highher the number, the less detail but the bigger the file size.
- keep the video image as still as you can. If it’s a headshot of you speaking, don’t move around much, and restrict movement of the camera. (see below for the reason why)
- Compress the video to reduce the file size
Below, you will see 2 videos showing
- how to compress a video on an iPhone, iPad or Mac using iMovie
- reduce file size in WIndows environments
This process will work for iPhone, iPad,
iPad touch and Macs
This shows how Windows users can use Camtasia to reduce file size
This "welcome" video is a 720p video
It's 22 seconds long, and its file size is 22MB
This "welcome" video is a 540p video
It's 22 seconds long, and its file size is 10MB
Here’s how compression works
Basically, compression makes videos smaller so that they are downloaded faster and they don’t use up people’s data allowance as quickly.
So, we could make the video smaller by making the number of pixels smaller.
The number of pixels is referred to as the number of lines of pixels from the top of a video to the bottom. This called changing the resolution of the video—1080 is what you’d get on most TVs nowadays
Changing the video from 1080 to 720 will reduce the file size from 60MB per minute to 40MB per minute
Changing from 1080 to 360 will reduce the file size from 60MB per minute to roughly 8MB.
Depending on your device you can also save as 540 or 480
If you are showing fine detail, then you’d probably want to go with 720 (DVD quality) but for most purposes, 480 or 360 will be fine
Compression also works on the “busyness” of the image. If you are waving your arms around, the image changes rapidly and the video needs to change every pixel every 1/25th of a second or so. If you are relatively still, with only your lips moving, the video only needs to change the pixels that describe your lips—it tells the playback software to use the same pixels for the background as it had on the previous frame