I have a problem in understanding data from ulog file.
Using pyulog I have converted ulog to csv files pyulog github
Now information I need is about “pictures” taken from the plane during the flight,
Time capture, and at that time
pressure
altitude
planes speed
roll,pitch,yaw
lat,long
After analyzing csv docs, I found some relevant data in different files such as
“camera capture”,“vehicle rates setpoint”, “differential pressure”
But according to timestamps these data don’t match,
I want to know how to find relevant data at that matching capture time,
I suppose that roll,yaw,pitch can be given as q[1],q[2],q[3]
But I am not sure,
I didn’t find relevant documentation about titles in csv files,
Please help, this is very important for me!
The different topics have the timestamps of when they were logged, so you will have to resample the data in order to match timestamps from different topics.
The attitude is logged as quaternions so you will have to convert them to Euler angles if you want roll, pitch, yaw.
Some more information of the topics are find in the message files
Thanks for answer, I found some useful information in message files,
What do you mean by saying “resample the data” ?
I have to collect data of image, time taken, roll, yaw, pitch of plane at that time in one excel file.
Although flight took only less than 1 hour timestamps in different topics have difference of hours,
How can I match them with each other, at least approximate correctly?
The timestamps should definitely not diff with several hours, could you please share a logfile?
It sounds like you want to do geotagging, have you read the documentation here? https://dev.px4.io/en/tutorials/camera_trigger.html
It don’t see anything wrong with the timestamps in the log, could you please clarify?
Sidenote: in the future please use logs.px4.io for sharing logs, and you are flying almost a year old code, but maybe you have good reasons for not updating to the latest stable release?
Sorry for unclarity, Let me clarify the problem,
The actual problem is that number of logged items in csv file(camera_capture)
is greater than number of photos taken.
For example in this log there are 281 items(seq) logged but number of photos taken is 229,
I think that the reason is that plane keeps logging during turnarounds,
although “Take images in turnarounds” is unticked in the QgroundControl,
And also this problem effects when we make Geotagging,
the images are matched according to the sequence in log file
and since number of items is greater than number of images result of matching is wrong.
What can be the reason for this problem ?
How can we solve it ?
