Capturing drone footage can be a pretty data-intensive process. From 4K videos and beautiful long time-lapse shots – not to mention the hundreds of photos you could end up taking – the storage of data has never been such a valuable resource. Here I want to share with you everything you need to know about drone video file size and the things you need to be aware of! I have REAL results from my experiment with one of my favorite drones – the DJI Mavic AIR…
Here are the rules of thumb for each common drone video quality which you can use as a guide for your drone capture purposes:
- 0.761 GB/minute at 4K/30fps MP4
- 0.523 GB/minute at 1080/60fps MP4
- 0.265 GB/minute at 1080p/30fps MP4
There is, of course, so much more that goes into determining what settings you should use to record your drone video. Here’s the data that you’ll find most useful when making these choices.
It’s not as much as you may think!
Common drone video file sizes
There’s a simple rule of thumb based on the research below that you can use to work out how much data your drone video content will require if you are recording in the MP4 format.
This data is collected from my drone and should be used as a guide for your drone’s video size.
| Quality | Frames per second | GB/minute | minutes/GB |
|---|---|---|---|
| 4K | 30 | 0.761 | 1.3 |
| 1080p | 60 | 0.523 | 1.9 |
| 1080p | 30 | 0.265 | 3.8 |
Therefore a good rule of thumb for 4K footage taken at 30fps is allow about 1 GB per minute of footage.
You can see from the last column in the above table that as the video quality and frame rate decreases so does the amount of GB per minute of footage.
There’s another way that we can look at this data too. Let’s say that you are in the market for a new memory card for your drone footage. What size memory card should you buy?
I’ve taken the data collected and calculated how many minutes of footage you can get from a standard array of memory cards at different quality and frame rates.
What size memory card should you buy for drone footage?
| Memory card size | Minutes at 4K/30fps* | Minutes at 1080/60fps | Minutes at 1080/30fps |
|---|---|---|---|
| 128 | 168 | 245 | 483 |
| 64 | 84 | 122 | 242 |
| 16 | 21 | 31 | 60 |
| 8 | 10 | 15 | 30 |
If you are a hobby drone videographer you’ll probably not need more than 64 GB of memory – that is about 2.5 batteries worth of flying time for most commercial drones.
However, if you are a professional drone company you’ll want a lot more storage on your memory car to make sure you have enough space for many multiples of flights.
To get these numbers I ran an experiment with one of my favorite drones (it is small and powerful) the DJI Mavic Air. I recorded at a number of different quality and framerates – ones that are typically used by hobby and professional drone flyers.
This was the outcome:
Real results from my DJI Mavic Air
The footage was collected on the internal storage of the DJI Mavic Air to overcome any issues in file write speed to an external SD card. The results suggest that this didn’t impact the
I ran at least three recordings at different video lengths to be sure that there is no artifact relating to the length of the video in the data.
This is what it looked like for each of my tests with the average of the results shown in the box below the table.
4K/30fps MP4
| Length of video (minutes:seconds) | File size (MB) | MB/minute | GB/minute |
|---|---|---|---|
| 1:08 | 866 | 764 | 0.764 |
| 3:01 | 2295 | 761 | 0.761 |
| 4:50 | 3671 | 760 | 0.760 |
Of these three video lengths tested with was the outcome:
Average = 0.761 GB/minute at 4K/30fps MP4
1080P/60fps MP4
| Length of video (minutes:seconds) | File size (MB) | MB/minute | GB/minute |
|---|---|---|---|
| 1:44 | 909 | 524 | 0.524 |
| 3:03 | 1589 | 521 | 0.521 |
| 5:11 | 2707 | 522 | 0.522 |
You’ll notice how much less the footage takes up on the storage. It is almost half despite being at 60 frames per second.
Average = 0.523 GB/minute at 1080/60fps MP4
1080P/30fps MP4
I do not have need to record my footage in 4K – yes I know that it would be nice BUT it takes up so much more space than I need and I always export my videos in 1080 so it just seems a little counter intuitive.
Here are the file sizes that I capture at different length videos and you’ll notice how much less per minute my footage takes up than the 4K equivalent!
| Length of video (minutes:seconds) | File size (MB) | MB/minute | GB/minute |
|---|---|---|---|
| 1:24 | 374 | 267 | 0.267 |
| 2:01 | 536 | 266 | 0.266 |
| 5:19 | 1411 | 265 | 0.265 |
| 6:29 | 1722 | 266 | 0.266 |
| 9:39 | 2560 | 265 | 0.265 |
| 12:41 | 1:24 | 265 | 0.265 |
This is significantly lower than both the 4K and the 60 frames per second equivalent. I often choose to work with these setting as they are more than enough for my needs.
Average = 0.265 GB/minute at 1080p/30fps MP4
So there we have it for my use case I use about 266 MB per minute of footage. That means that I can get 3 minutes and 42 seconds per GB of memory card space!
How SD cards and FAT32 systems handle drone video file size
You may have noticed that when you are recording long video formats on a drone the video will often be split up over two video files.
That is not because of the drone but rather the FAT file system that the SD cards use.
One drone enthusiast noted:
My mp4 files are always 3.99GB large.
Filmed at 4096×2160, 30fps they are 5:27min long.
Filmed at 1920×1080, 60fps they are 6:49min.
The 4 file size is a limit for the FAT32 file system which is what the SD cards use.
If you want to avoid having the video spread over multiple shots you’ll either have to reduce the quality of the video so that you can get the total recording under 4Gb or you have to manually stop and start recording.
To be honest, I’ve never had an issue with connecting two video files together in my video editor. One always seamlessly connects with the other.
Maybe you want to reduce the file size of the video that you have recorded this next section is for you!
How to reduce drone video file size
Video size is dtermined by two important factors:
- Encoder – a device or software that enables video compression and/or decompression for digital video.
- Bit rate – A video bitrate is the number of “bits” that are processed in a unit of time. Video data rates are given in bits per second. The data rate for a video file is the bit rate. So a data rate specification for video content that runs at 1 megabyte per second would be given as a bitrate of 8 megabits per second (8 mbps).
Commercial drones typically use MP4 and MOV export settings but the file name has NOTHING to do with the size of the exported video. It is the bitrate and sample rate that will determine the size of the file.
1: Exporting to a lower bitrate examples:
Here some example file sizes and it’s dependence on bit rate.
| File type | Bit rate (Mbps) | File size (GB per minute) |
|---|---|---|
| MP4 | 30 | 0.226 |
| MP4 | 20 | 0.151 |
| MP4 | 15 | 0.113 |
| MP4 | 10 | 0.076 |
Quite often we do not get a chance to choose the bitrate at which our drones record – or it can be too much of a pain to change mid flight.
In that case you have a couple of options to choose from if you want a lower file size while flying.
2: Choose a lower resolution
As we’ve seen from the above tables, the quality that you record in has a huge impact on the size of the file that you ultimately end up with and have to download to your computer.
Choosing a quality that makes sence for your project is the only way that
If you are exporting in 1080HD – there’s probably no need to go to 4K. On the other hand, if your client is using the video for a multitude of purposes you may want to have the insurance of a 4K image.
3: Stop and start recording as you need to
It can be tempting to push record at the very beginning of your flight. I know that quite often I even record the take off – just to be sure!
However, if you want to reduce the drone video file size you may want to consider stopping and starting your drone footage as you are happy with the framing of the shot.
This will save you a lot of space on your SD card and also make for easier editing when you come to import it into your favorite video editor!
