Phantom 3 drone down

You don’t need to throw the card away.

Try downloading a video file repair program, there are free ones available. You can also use VLC Media Player (also free). I’m told it will attempt to repair a corrupt AVI index so good chance it will let go see those final moments Rod is desperately waiting to see.

Pleased to learn you found your AC.
 
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sar104 said:
There's actually no simple way that I know of to automate altitude AGL estimation along a defined track, but I can describe the method I use in case it is of interest to anyone or, even better, if anyone can suggest a more efficient method.

Litchi exports a kml file that defines track points at the mission waypoints (plus 4 extra track points per waypoint to define each curved turn). For the current example that looks like this:

View attachment 93214

We can extract the lat/long pairs from the sparse output, import them into Igor Pro, and run a custom function to create cumulative distance for each waypoint. The kml file also gives altitude AGL at each track point, based on Litchi's DEM and the mission waypoint altitudes above the take off point, so now we have lat/long/distance/altitude AGL values, but it has no information about altitude AGL between the track points, and so the values are only correct at those track points:

View attachment 93215

GE can display a continuous, interpolated, altitude MSL profile for this track, and you can also clamp it to ground to get a continuous ground elevation profile MSL under the track, but it will not display the difference and you cannot export the data, so that's a dead end in terms of trying to generate the flight altitude AGL resolved across the entire track.

However, we can use the GPSVisualizer website tool to apply a DEM that discards the altitude data, creating a second file that has ground elevations MSL rather than flight altitude.

View attachment 93216

Now we have two data files, one describing the flight path altitude AGL and another describing the ground track altitude MSL under the flight path, but only at the sparse waypoints that define the mission. If we add these datasets then we can reconstruct the mission altitudes MSL at the mission exported track points:

View attachment 93217

Note that it looks approximately as expected, since all but one mission waypoint had identical altitudes above the takeoff point. The variation, which is of the order of a couple of meters, is due to differences in the DEM used by Litchi vs. the DEM used in this calculation.

The linear interpolation of the flight altitude MSL is usable, since that is how Litchi flies the mission. That's not so for the ground track elevation data however, since the ground does not behave like that in general between mission waypoints. It would be great if GPSVisualizer could take such a track defined by sparse track points and create an elevation profile at an arbitrary spatial resolution, but it will not do that - it only returns elevation data at the input track points.

To get around that problem, we can take the lat/long/distance/flight altitude MSL data and run a linear interpolation scheme to produce new values at equal distance intervals. In this case I created 1000 interpolated triplets giving a uniform spatial resolution of approximately 5 meters:

View attachment 93218

View attachment 93219

Processing those track points again using GPSVisualizer's DEM also generates a much higher resolution ground elevation profile:

View attachment 93220

Now we can subtract the high-resolution ground elevation profile from the flight altitude MSL profile to get a high-resolution flight altitude AGL profile:

View attachment 93221

Comparing this to the second graph that shows only flight altitude AGL at the exported track points illustrates the reason for generating the higher resolution ground profile.
Click to expand...
We need to put this in the sticky thread. This is so useful. Thank you sar104 for that mate [emoji4]
 
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With The Birds said:
You don’t need to throw the card away.

Try downloading a video file repair program, there are free ones available. You can also use VLC Media Player (also free). I’m told it will attempt to repair a corrupt AVI index so good chance it will let go see those final moments Rod is desperately waiting to see.

Pleased to learn you found your AC.
Click to expand...

Agreed, VLC has repaired a few files for me when I first started flying and would forget to stop recording before turning off the remote. There are a few programs out there as well that say they will write an end of file for you but I have only had that work 2 times with any of those. And some files are just beyond repair also. Then there's those DAT files that you need to find on the card. The one for this flight may still be good and should have valuable info on it...
 
robby4570 said:
Agreed, VLC has repaired a few files for me when I first started flying and would forget to stop recording before turning off the remote. There are a few programs out there as well that say they will write an end of file for you but I have only had that work 2 times with any of those. And some files are just beyond repair also. Then there's those DAT files that you need to find on the card. The one for this flight may still be good and should have valuable info on it...
Click to expand...
The .dat files are written to an SD card inside the AC, not in the removable card that stores photos and footage.
 
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With The Birds said:
You don’t need to throw the card away.

Try downloading a video file repair program, there are free ones available. You can also use VLC Media Player (also free). I’m told it will attempt to repair a corrupt AVI index so good chance it will let go see those final moments Rod is desperately waiting to see.

Pleased to learn you found your AC.
Click to expand...
Ok, i will give one a try
 
rickatom said:
Sorry.....i did retrieve files on my pc. Windows media
Are you saying throw the card away?
Click to expand...
No, Don't use the card to do the repair, what is on the card is you only original copy.
Copy from the card, do the repair on your PC.

@LUIS J, fine tuned, or made the DJIFIX program little easier to use.

You use a video that you know is the same settings as the one that is damaged.

Pick the file that is damaged, pick a file that has the same settings, and run it

When you run this program it does not modify the damaged one, or the good one, it creates a new file from it, so your original will be untouched.

This is the beginning of his thread.
App to fix corrupted Video Files (new one)

Page# 8 Post# 147 ;) Is a link to his program.
App to fix corrupted Video Files (new one)

When I downloaded in the past, I created and copied to folder in the root of Drive C: "Fixit"
Copy your good file and your corrupt file to same folder, makes it little easier then chasing were the files are when you run the program.
This may get you around Administration Rights issues.

The program will be zipped.

Page# 8 Post# 104 ;)
The original creator of DJIFIX chimed in. Stating his is free, Luis asks for a small donation.
App to fix corrupted Video Files (new one)

Your Turn. :D

Rod
 
Last edited:
With The Birds said:
You don’t need to throw the card away.

Try downloading a video file repair program, there are free ones available. You can also use VLC Media Player (also free). I’m told it will attempt to repair a corrupt AVI index so good chance it will let go see those final moments Rod is desperately waiting to see.

Pleased to learn you found your AC.
Click to expand...
VLC is the most Popular, but I quit using it, I have liked Pot Player better.
I install all the added codec's when they ask.

https://lifehacker.com/five-best-desktop-video-players-1503859883

Rod
 
rickatom said:
I tried the vlc and it ran for quite awhile. I tried to view after it stopped. Nothing
Click to expand...

This must mean you haven't tried a repair?

Pot Player is not going to finish playing it ether.

Rod
 
RodPad said:
This must mean you haven't tried a repair?

Pot Player is not going to finish playing it ether.

Rod
Click to expand...
I have tried a few programs that are supposed to fix corrupt sd. Trying to work with the dji exe program now.
Once i get my parts in to repair my camera connection, will it finalize the video? Or is it still bad because power was lost.
 
I doubt it, that would have been the first power up after the battery was ejected.

I guess you haven't tried my link.

If you load up the bad file and a good one to a dropbox etc, I will run the app for you myself.

Rod
 
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RodPad said:
I doubt it, that would have been the first power up after the battery was ejected.

I guess you haven't tried my link.

If you load up the bad file and a good one to a dropbox etc, I will run the app for you myself.

Rod
Click to expand...
Yes Rod, I did try your link. No go for me
 
Last edited:
Well it appears only one file is coming in DJI_0008.mp4 , Is this the good one or bad one, as I stated above we need a good one recorded at the same setting to repair the corrupt one. If your cheap like me and ran out of space, I let you know when I get this one and you can delete and upload the other.

Rod
 
RodPad said:
Well it appears only one file is coming in DJI_0008.mp4 , Is this the good one or bad one, as I stated above we need a good one recorded at the same setting to repair the corrupt one. If your cheap like me and ran out of space, I let you know when I get this one and you can delete and upload the other.

Rod
Click to expand...
Dji00008 is the bad one. I thought i had sent a good video also. Still sorta new at this file sharing stuff. I ll try again when i get home.
 

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