Still strange behavior during track recording

novus · July 14, 2011, 07:05:26

Hi.

I start a new thread on this subject, although it's probably the same error I had when I posted in "Auto switch to " pause " mode during track recording"...

It has nothing to do with "pause"-mode. Also there is no dependence on screen's switch off.

It is just a stop of recording available (!) positions.

So, what happened?

I went by car (as a passenger) for more than 1 hour. So I had some time to start experimenting.

The track-recording started and I saw the red line.

But just after a few points the line stopped although the position (by the arrow) was shown correctly. That means, locus knew the correct position but did not write it into the track.

By pressing the "pause"-button, locus was obviously forced to write the last position into the track, so the red line was drawn from the last recorded point to the position where I pressed "pause". A lot of points between (although they had been registered and shown by the arrow) missed.

Pressing "record"-button again (the big red dot on button) made locus in average writing the next two or three points (sometimes more, sometimes even not a single one) again until the error occured again.

Remark: the correct position was availible the whole time (arrow was correct, exactly on the street, also following curves).

One time I had the following phenomenon: When screen was on, I saw that the red line stopped. I did nothing and waited for auto-screenoff. When I switched screen on again, the track had continued and the red line was correct even at the points that before had not been shown. But this was only one time and not (!) reproducable. :?

Version: 1.9.0.2

The parameters: GPS-refresh every 2 seconds, intervall of track recording 3 seconds.

I use android 2.2.1 on a Samsung Galaxy S I9000.

Remark: I'm not sure, but it seems to me that it may depend on velocity. I had this error only, when I went by bike or by car, never, when I went by foot... :!: :?:

Menion · July 14, 2011, 08:18:22

hmm pretty interesting. Did you saved this track then? There is also chance that track was recorded correctly and problem was only drawing on the map. So may you test it with last market version if problem is in recording (so saved track also have missing points) or problem is only with display. You may also help me to test this, by enabling saving NMEA messages in GPS settings (only during track record is enough) so I can then simulate exactly your recording thanks to saved NMEA file

svartbjorn · July 14, 2011, 08:40:14

Exactly same thing happened to me yesterday, using the latest version of Locus Pro.

I was out flying. Screen on all the time, GPS posistion every 1s, recording point every 2s. It was 1 hour flight, and the red recorded line showed up on the screen, continuously updating. But about 3 minutes before landing, the red track stopped, but my position was still updated. After landing, everything looked normal except for the missing last 3 minutes. The recording menu was still there, and I pressed STOP. The saved track is missing the same last 3 minutes, and when I tap on the last visible point on the track, the point has status "Distance to end" = 0m. So this is not a display problem, it is a recording problem.

This is the first time I have seen this problem. I recorded 5 other trips the last two days (two by bike, three by car) without any issues.

novus · July 14, 2011, 08:43:55

Hi menion.

Yes I saved the track. I also displayed the track again after reboot the phone. The missing points were still missing.

So how can I help you?

I understand you this way:

1.) record another track while having enabled saving NMEA messages in GPS settings and then send you the recorded data, right?

2.) Do you need the recorded track of yesterday also?

Question: Which data can I send to you in what way...?

Menion · July 14, 2011, 12:50:16

svartbjorn: you're able to record tracks without crash now? How's this possible?

and ...1) yes ... when you record this NMEA file, I (or whoever) can place it into Locus/cache/nmea and then when I enable GPS in Locus, I can choose this file and simulate your ride, so also with track recording. So I hope this will help me to find source of troubles. I'm anyway sorry for that and I really hope that I'll fix this soon

2) nono, this do not help me

novus · July 14, 2011, 13:09:30

O.K., I'll try my best. But I can't promise to reproduce it soon, because as svartbjorn wrote, this error does not occur during every track-recording.

For example today (one hour ago during my lunch-break) I did a recording by foot - without any problems.

Tomorrow I'll try the same track by bike (higher velocity). The way I am going / biking is the same, on which the error occured the first time - also while using my bike...

When I have the file then, I'll attach it to a post here in this thread.

novus · July 14, 2011, 13:20:48

Me again...

One question: is there an algorithm implemented in track recording to minimize the number of recorded points?

Sometimes it looks as if the number of points is reduced on straight parts of tracks and increased in case of changing direction.

If so, I would try to search the error there. When I look at my tracks, the error occurs on straight parts of the track...

Menion · July 14, 2011, 13:24:18

nono nothing like that. If point will be saved is determined simply by values in settings. If point pass all required values (min distance, time, accuracy, ...) it will be saved. No more filtering or something like that. And file do not hurry. When this happed and you'll have NMEA file, it will be fine and I'll be able to try to find a problem. I'll try to record by myself as much as possible also

svartbjorn · July 14, 2011, 13:43:37

Quote from: "menion"svartbjorn: you're able to record tracks without crash now? How's this possible?

Thanks for asking Menion, how my phone is doing without crashing. I did what you suggested: replaced the microSD card. I copied the whole contents from the 32GB microSD card to my PC, put back in my old 8GB card and simply copied back from the PC to the microSD 8GB in the phone (just leaving out some large Locus and Copilot maps due to less space). Everything came up fine. I didn't have to reconfigure anything. This is only 3 days ago, so limited experience. But I record all the trips I make to test this out. So far both the Locus recording and the phone have been rock solid! I do not feel convinced yet until I have gathered some more experience.

The net shop where I bought the 32GB card 7 months ago, accepted a replacement without any further questions. I'll get the new 32GB card (same manufacturer Kingston) next week. My guess is that there could have been some initial production issues since I got hold of one of the very first samples of the 32GB Class 4 card that become available on the market from Kingston. A colleague of mine has the same phone and same 32GB card and has had no issues at all with Locus recording, but he bought his card much later than me. So I am crossing my fingers hoping that it really was the microSD card that was the root cause of all these troubles the last 6 months.

Menion · July 14, 2011, 14:29:58

I told it remember

... I have also 32GB card and my problem is that this card is really slow. So normal map browsing is almost unusable becase storing map tiles to database takes a long time so I rather browse online maps without storing data. I also tested on 8GB card and this is damn fast ... so I have also experience with 32GB card

. But this is little bit offtopic. Anyway I'm really glad that you can finally use locus track recording

novus · July 15, 2011, 07:42:33

Hi menion.

Here is an NMEA-File of a track, which had half the error.

That means, that the track did not completely stop but lost a lot of points with available positions.

I added a screenshot of the track with manually added hints.

Short description:

1.) This is where I switched on GPS and got the fix with accuracy of 5 m. Then I switched the screen off and started biking.

2.) Here I made a short stop to have a look. So I switched on the screen, looked (track looked o.k.), and switched the screen off again. This in the recorded track is point no. 14. I went on biking.

You can see that from then on one more point is recorded, before a lot of points is missing although the position probably was available (from my experience with my track in the car, I described above). I followed the street "Am Kesselberg".

3.) Here locus wrote a position again. This happens if you are lucky. When I went by car, it often didn't. Instead no more point was written for an long time (more than a minute), so I had to force locus to write by pressing pause and record again. Maybe that locus would have started writing again after a few minutes, but that of course is not satisfying...

The points are numbered correctly within the track, that means the stop (2) was at point 14, then number 15 was recorded and the first recorded point after the missing positions has the number 16. By the way: within the part of the track, where the points are missing, my velocity was the highest, for it's going down a hill...

The parameters were the following:

Track recording: Intervall 1m, 3s

GPS: refresh 2s

So, although this is only half the error, I hope this will help you to find the problem.

Thank you for your help!

[attachment=0:2ldzy2jh]menion_track.jpg[/attachment:2ldzy2jh]

novus · July 15, 2011, 07:43:38

Hmmm... Where is the attached NMEA-file...?

Next Trial.

EDIT: How can I attach the NMEA-file? It isn't shown here, although I uploaded it... Probably too big

EDIT 2: It's even too big for PM... :x (abaout 161.000 characters)

So how can you get it, menion? :oops:

Menion · July 15, 2011, 08:05:26

why don't you send me it by email? mailto:locus@asamm.cz">locus@asamm.cz ... thanks!

novus · July 15, 2011, 08:06:08

o.k., I'll do it.

EDIT: done.

Menion · July 15, 2011, 21:06:12

hmm this is really weird ... I was playing your NMEA file few times and all data are correct, so for a whole track, there was a valid location with excellent accuracy. damn ...

So, if this happen to you periodically, I can only do some debug version that will write logs into file, so I'll hopefully be able to find place where is "mistake". Is this possible?