Update: Now compatible with After Effects:

And for more use cases, check out Telemetry Overlay:


And Telemetry Extractor:


SRT logs have been there in our SD cards for a while. They appear when you turn on "Video Captions" in the Go4 App, but they are not very accurate (not enough location digits are included, only recorded once every second...), so not many people have been using them for anything.


I decided to give them a try, and have been playing with ways of visualizing them. It turns out they can provide some interesting information if you combine data entries to smoothen the paths, speeds and so on. Accuracy is still an issue DJI should address, but I find it fun to visualize the paths of my flights and get an approximation of speeds, distance and so on.

Feel free to test the tool I created. Please share anything fun you visualize with it, report bugs, suggest new features and send me your drone's logs if they are not supported yet. I will clean up and publish the source code for anyone to contribute when I get some spare time.

Here it is: https://djitelemetryoverlay.com

If all goes well, I will be implementing things like these in the near future:
- Support for other drones/trackers
- Different playing speeds
- Merge more than one SRT file (useful if the recording was interrupted)
- Export data to formats like gpx or kmz

I get a blank page on the latest versions of MacOS/Safari. Seems to render ok in Chrome and Firefox. Looks pretty cool!

Ex Machina Posted at 2018-3-12 18:11
I get a blank page on the latest versions of MacOS/Safari. Seems to render ok in Chrome and Firefox. Looks pretty cool!

Thanks. Yes, just tested on Safari and got the same problem. Will try to fix it, but for now let's say the tool is compatible with Chrome, Firefox and Edge only

Now it works with Safari too

I'll give it a try, thanks for sharing!

Hi, there. Please note that we would recommend users export the flight data and the black box to us for analysis when you crash your drone. Thanks for your support.  

DJI Elektra Posted at 2018-3-18 02:29
Hi, there. Please note that we would recommend users export the flight data and the black box to us for analysis when you crash your drone. Thanks for your support.

Sure. This tool is not for crash analysis but for fun and creative uses.

this looks really interesting - i remember looking at my logs a long time ago and giving up - i will check it out again. thanks and well done

Anyone knows what happened to .SRT files. My Inspire 1 used to create an srt file with every mov file, no longer.

UAViator53 Posted at 2018-3-26 17:56
Anyone knows what happened to .SRT files. My Inspire 1 used to create an srt file with every mov file, no longer.

Have you checked that your Video Captions setting is still on in the Go4 app?

0Kajuna0 Posted at 2018-3-26 23:11
Have you checked that your Video Captions setting is still on in the Go4 app?

Great tool, but could you please explain what the "Video Captions" setting normally is meant to do?

Great info - thanks for sharing     

Wachtberger Posted at 2018-3-26 23:27
Great tool, but could you please explain what the "Video Captions" setting normally is meant to do?

It just creates a subtitle file so you can see GPS and other information over your video.

Here's an example (turn on youtube captions):

0Kajuna0 Posted at 2018-3-27 01:33
It just creates a subtitle file so you can see GPS and other information over your video.

Here's an example (turn on youtube captions): https://youtu.be/imSIDzRl0CE?t=26s

Great feature, thank you very much for explaining it!

0Kajuna0 Posted at 2018-3-27 01:33
It just creates a subtitle file so you can see GPS and other information over your video.

Here's an example (turn on youtube captions): https://youtu.be/imSIDzRl0CE?t=26s

Great info!      

I just published the source code of the site. If anyone wants to contribute with fixes or new features, they are more than welcome: https://github.com/JuanIrache/dji-srt-viewer

Does not work with Mavic Air SRT files using Chrome, says file not supported.

Hummingbird.UAV Posted at 2018-4-3 07:58
Does not work with Mavic Air SRT files using Chrome, says file not supported.

Could you paste a section of your SRT files? Or send it to me privately?

The last thing I heard about Mavic Air SRTs is that someone reported the location data was missing. I'm not sure if that's been fixed in the latest firmware versions.

https://forum.dji.com/thread-136508-1-1.html

If there is GPS data I'll adapt the viewer to read them.

0Kajuna0 Posted at 2018-4-3 11:19
Could you paste a section of your SRT files? Or send it to me privately?

The last thing I heard about Mavic Air SRTs is that someone reported the location data was missing. I'm not sure if that's been fixed in the latest firmware versions.

Hi here are the first four lines of Mavic Air's SRT file.  If the MP4 is played in VLC the SRT data shows if close caption is turn on in VLC.

1
00:00:00,000 --> 00:00:00,033
<font size="36">FrameCnt : 1, DiffTime : 33ms
2018-02-27 14:22:37,016,851
[iso : 100] [shutter : 1/2000.0] [fnum : 280] [ev : 0] [ct : 5702] </font>

2
00:00:00,033 --> 00:00:00,066
<font size="36">FrameCnt : 2, DiffTime : 33ms
2018-02-27 14:22:37,050,221
[iso : 100] [shutter : 1/2000.0] [fnum : 280] [ev : 0] [ct : 5702] </font>

3
00:00:00,066 --> 00:00:00,100
<font size="36">FrameCnt : 3, DiffTime : 34ms
2018-02-27 14:22:37,083,585
[iso : 101] [shutter : 1/2000.0] [fnum : 280] [ev : 0] [ct : 5702] </font>

4
00:00:00,100 --> 00:00:00,133
<font size="36">FrameCnt : 4, DiffTime : 33ms
2018-02-27 14:22:37,116,951
[iso : 100] [shutter : 1/2000.0] [fnum : 280] [ev : 0] [ct : 5702] </font>

0Kajuna0 Posted at 2018-3-27 01:33
It just creates a subtitle file so you can see GPS and other information over your video.

Here's an example (turn on youtube captions): https://youtu.be/imSIDzRl0CE?t=26s

This is a cool feature. Thanks for sharing!

Hummingbird.UAV Posted at 2018-4-3 13:42
Hi here are the first four lines of Mavic Air's SRT file.  If the MP4 is played in VLC the SRT data shows if close caption is turn on in VLC.

1

Unfortunately that does not include any location information. You guys will have to wait for DJI to implement this feature on the Mavic Air

0Kajuna0 Posted at 2018-3-27 01:33
It just creates a subtitle file so you can see GPS and other information over your video.

Here's an example (turn on youtube captions): https://youtu.be/imSIDzRl0CE?t=26s

good to know thank you!!

HenryHM Posted at 2018-4-17 23:42
good to know thank you!!

No worries.

By the way. I see people use the SRT Viewer website in my analytics. It would be cool to know what you guys use it for, see screenshots of your flights, get feedback on the tool's capabilities and so on. Don't be shy ;)

App updated to enable exporting flight data to KML (for Google Earth), GPX and GeoJSON (for many other services and systems). Let me know if you encounter any bugs or have any requests .

http://tailorandwayne.com/dji-srt-viewer/

Updated. Now you can import and visualize GPS data from other devices, GoPros for example (KML, GPX, JSON and GeoJSON). Please let me know if you encounter any bugs.

Hey all - just got a Mavic 2 Pro recently. I have enabled "Video Caption" and am seeing the SRT files alongside the .mp4 videos, however, they do not include GPS info. It looks like it's just frame number, timestamps, and camera info (shutter, iso, etc..). No GPS info.

Anyone know how I get GPS telemetry info to be written to the SRT files as well?

rimig Posted at 11-1 05:45
Hey all - just got a Mavic 2 Pro recently. I have enabled "Video Caption" and am seeing the SRT files alongside the .mp4 videos, however, they do not include GPS info. It looks like it's just frame number, timestamps, and camera info (shutter, iso, etc..). No GPS info.

Anyone know how I get GPS telemetry info to be written to the SRT files as well?

I don't think it's possible on the Mavic 2

0Kajuna0 Posted at 11-3 09:16
I don't think it's possible on the Mavic 2

Yea it didn't seem like it. I was able to get what I needed by syncing the flight records via airdata.com and then exporting CSVs/KMLs of the telemetry data

Now updated with a button to download video of the visualisation: http://tailorandwayne.com/dji-srt-viewer

Thanks to Marcelo Saviski for the contribution!

I activate video caption and got the srt files but each time I try to use it in video geottager software, nor Dashcam Viewer nor tailorandwayne.
I get error message of gps data can´t be read or incompatible data or something like that.

Anybody has found out any new information with problems on srt files of Mavic 2?

RIMC1234 Posted at 12-4 08:34
I activate video caption and got the srt files but each time I try to use it in video geottager software, nor Dashcam Viewer nor tailorandwayne.
I get error message of gps data can´t be read or incompatible data or something like that.

As far as I know the Mavic 2 srt files still don't include location data. We'll have to wait for DJI to solve this, but it's not looking good.

RIMC1234 Posted at 12-4 08:34
I activate video caption and got the srt files but each time I try to use it in video geottager software, nor Dashcam Viewer nor tailorandwayne.
I get error message of gps data can´t be read or incompatible data or something like that.

Great news! According to this post, Mavic 2 files now include GPS location data! (No altitude, though)

https://forum.dji.com/forum.php?mod=viewthread&tid=173891

I have tried to guess how the M2 files work, and updated the app accordingly, but I have not had the chance to test it. So if anyone could send me Mavic 2 SRT files, here or privately, I would really appreciate it.

Heya that looks cool.

I`m going to try it!!

Thanks.

I can CONFIRM the Mavic 2 with the latest firmware includes GPS location data (no altitude) in SRT files (Caption option) and that the DJI SRT Viewer can read and visualise them!

http://tailorandwayne.com/dji-srt-viewer/

0Kajuna0 Posted at 3-26 23:11
Have you checked that your Video Captions setting is still on in the Go4 app?

Just a question please.

Does the video captions show in the final video?

HendrikJB Posted at 12-9 10:52
Just a question please.

Does the video captions show in the final video?

No. They're on a separate file that you can activate in some video players (VLC for instance). The video itself is clean

0Kajuna0 Posted at 12-9 15:47
No. They're on a separate file that you can activate in some video players (VLC for instance). The video itself is clean

Thank you very much for the information.

When I discovered the srt file ...we could use this file only for the start and stop positions.
Copy these in an Excel file, adding the telemetry data, to get from an other source, in extra cols, generating a text string and copy the recs into a txt file, rename it as srt... this could be the trick to have the telemetry as subtitle.

Dominique De Roeck Posted at 3-10 04:57
When I discovered the srt file ...we could use this file only for the start and stop positions.
Copy these in an Excel file, adding the telemetry data, to get from an other source, in extra cols, generating a text string and copy the recs into a txt file, rename it as srt... this could be the trick to have the telemetry as subtitle.

Sorry, not sure what you mean

Update: Now you can also load your GoPro GPS tracks directly onto the tool from this web-app I made

https://tailorandwayne.com/gopro-telemetry-extractor/