Overlay Flight Data Using SRT Files

Joined
Sep 21, 2015
Messages
57
Likes
24
Age
48
#1
I do some survey stuff and need flight data overlayed on the Video. Dashboard as good as it looks, is over the top. I needed a plain text subtitle. The SRT files that DJI_Go puts out is good. Never see it used though, so How many people know about it? If you haven't used this here is the proceedure I use.

Be shure to set "Video Caption" ON in the camera menu.

When you download your movie files from the on board SD card for each MOV or MP4 File you will get an SRT file.

SRT file are just gloryfied text files but with information to keep them in sync with the picture.

My Editor is Power Director but I suspect any reputable editor that can put subtitles up will do it. It is information that is changing on the run but it's dead in sync.


upload_2015-10-18_16-28-27.jpeg


The SRT file can be edited with find and replace, in most text editors, in the example I have substituted BAROMETER for ALTITUDE. I would like to be able to get Heading in but DJI seem to be a bit coy about expressing gyro in 360 degree notation. Any comments / questions?
 

FredzMaxxUAV

Approved Vendor
Joined
Jun 25, 2015
Messages
592
Likes
128
#2
Using the free program Subtitle Edit, Subtitle Edit , you can actually merge/append multiple SRT files, which comes in handy when you need to merge videos from longer flights... It's good to get a quick altitude display on screen, without having to resort to Dashware at once.
 
Joined
Sep 21, 2015
Messages
57
Likes
24
Age
48
#3
Using the free program Subtitle Edit, Subtitle Edit , you can actually merge/append multiple SRT files, which comes in handy when you need to merge videos from longer flights... It's good to get a quick altitude display on screen, without having to resort to Dashware at once.
Thanks for that, must try it. I have found Litchie csv files now, so can get gryo and more data. With a cobbled together text editor I get my own format, and choice of data.




Big_A
Using the free program Subtitle Edit, Subtitle Edit , you can actually merge/append multiple SRT files, which comes in handy when you need to merge videos from longer flights... It's good to get a quick altitude display on screen, without having to resort to Dashware at once.
Thanks for that, I will try it. I have now discovered Litchie CSV files so am getting more data to use.
Using a cobbled tother test edititor I get this sort of thing


SnapShot(0).jpg


Big_A
 
Joined
Sep 21, 2015
Messages
57
Likes
24
Age
48
#5
Fredz,
They are SRT files like this

100
00:01:50,000 --> 00:01:51,000
Time 2015-07-30 12:48:43 Latitude 51.44616 Longitude -0.87327 Hdg 101
Altitude 0415 Feet AGL Speed 00 MPH Distance From Home 00458 Feet
Polar Screen Test At Black Swan Lake

101
00:01:51,000 --> 00:01:52,000
Time 2015-07-30 12:48:44 Latitude 51.44616 Longitude -0.87327 Hdg 101
Altitude 0434 Feet AGL Speed 00 MPH Distance From Home 00459 Feet
Polar Screen Test At Black Swan Lake

it whent like this:
1) Got DJIFlightRecordfile.txt From DJIgo>Flight Records . easy on Android but need ITunes with Ipad. They are text files but unreadable.
2) Upload to Lichie then it comes back as an CSV which reads good in Ms Excell
3) Used a home made Visual Basic text editor to extract which data I need , format it ,and create the SRT file.
The difference from this SRT file and the one you get from downloading from your P3 with the MOV files is, these files run from power on the power off. The MOV file may have started after power up and may continue until after power down So you have to syncronize them.
4) I put the picture together in PowerDirector 13 which allows you to choose fonts colour, size and justification.

Big_A
 
Joined
Sep 21, 2015
Messages
57
Likes
24
Age
48
#7
Fredz,
If I lose connection the last think i am going to worry about is recording subtitles. Yes you are right about the Litchie and Healthy Drone collaboration.
 
Joined
Jan 2, 2018
Messages
93
Likes
26
#9
So while this is a rather old thread, I am hoping someone can answer this important question this raises for me....

I notice the the Litchi file he has above takes the GPS coordinates out one more number, which is HUGE for me. Four decimal places was not quite enough for me. But five decimal places will do it!

Can someone please confirm whether an SRT (specifically SRT or is it a different type) file comes out with GPS coordinates that show to the 5 decimal place in Litchi app???

THANKS!
 

New Threads

Forum statistics

Threads
130,324
Messages
1,352,418
Members
94,996
Latest member
jeffchicago