- Joined
- Sep 9, 2019
- Messages
- 17
- Reaction score
- 24
- Location
- Orange County, California
- Website
- mydroneviewer.com
So I've been probing my .a-s-s logs and have made a few discoveries. 
Just to refresh, .a-s-s files are a real thing and can be turned on in the app settings. (The actual extension is .a-s-s without the dashes. I'm using the dashes since the forum software changes the this to .a**).
When enabled, the .a-s-s files contain per-video trajectory data, which is used by DroneViewer for synchronized playback with the video. The .a-s-s files are saved on the SD card alongside the video files. This makes the trajectory data easily and conveniently available (thanks Autel!). Not surprisingly, DJI also records per-video trajectory data in their SRT file, which is enabled in a similar manner.
The problems with the EVO .a-s-s files are as follows:
Thanks!
Autel EVO .A-S-S file, v4.00+:
HOME(-117.9606, 33.6324) 2019.9.8 16:49:24\NGPS(W: -117.-9605, N: 33.6323, -37) ReH:0 \NISO:100 SHUTTER:1000 EV:0 F-NUM:2.8
Mavic Pro 2 Zoom SRT file:
[latitude : 60.192410] [longtitude : 24.843398]

Just to refresh, .a-s-s files are a real thing and can be turned on in the app settings. (The actual extension is .a-s-s without the dashes. I'm using the dashes since the forum software changes the this to .a**).
When enabled, the .a-s-s files contain per-video trajectory data, which is used by DroneViewer for synchronized playback with the video. The .a-s-s files are saved on the SD card alongside the video files. This makes the trajectory data easily and conveniently available (thanks Autel!). Not surprisingly, DJI also records per-video trajectory data in their SRT file, which is enabled in a similar manner.
The problems with the EVO .a-s-s files are as follows:
- The longitude value is recorded with an extraneous character. See snippet below. Notice the current position longitude is "-117.-9605". The second '-' sign should not be there! Funny thing is that the home point longitude is recorded correctly.
- The latitude and longitude coordinates are recorded out to only 4 digits past the decimal. This equates to a resolution of approximately 33 feet! When plotted on a map, the results is a stair-step trajectory pattern, even though the drone is flying in a straight line. The coordinates should be recorded out to 6 decimal places (0.3 feet). Notice the SRT file for the Mavic Pro 2 Zoom records out to 6 decimal places and the trajectory is smooth, as shown in the graphic below.
- A minor bug is that the data record has a "\N" in it, when I think they meant to write "\n" (carriage return).
- Another minor bug is that Latitude and Longitude ordinal values (N/S or E/W) are printed out, but these can be inferred by the positivity or negativity of the latitude or longitude values. For example, -117 longitude implies "West" so having both a negative sign and "W" is redundant. Like I said, it's a minor nit!
Thanks!
Autel EVO .A-S-S file, v4.00+:
HOME(-117.9606, 33.6324) 2019.9.8 16:49:24\NGPS(W: -117.-9605, N: 33.6323, -37) ReH:0 \NISO:100 SHUTTER:1000 EV:0 F-NUM:2.8
Mavic Pro 2 Zoom SRT file:
[latitude : 60.192410] [longtitude : 24.843398]
