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New app: TelloFPV for Android

I will try this evening after work. Had no chance to test yet, either with the expert settings or new release.
Okay.. I tested the combination Tello FPV 1.4a P with Copilot 1.4a-copilot N without enabling Expert mode. Phone battery level after finshing the test 63%, on Tablet 85%.
Picture freezes: None occurred.
Delay behavior unchanged to yesterday. The same lags, unprecise execution of commands.

Afterwards I quit the Copilot App on the Tablet, confirmation appeared in TelloTPV (Copilot disconnected). Direct takeoff with Tello and all the Lags were gone. So the lags seem to be a direct side effect from the Copilot Connection.

If I should try with some expert settings, please advise.
 
Thanks for the test. Yes, please test with increased thread priorities:

Please set "heartbeat" = 6 and "send handler" = 7, then press "apply + restart" and try again.
Afterwards try "heartbeat"=7 and "Send handler"=6 to se if that makes a difference.

It could well be that your phone is simply overloaded if Copilot is connected as well. What phone model are we talking about (for tellofpv)?
 
Ok, so these are the results with hb = Heartbeat and sh = Send Handler
hb 6, sh 7 no effect
hb 7, sh 6 no effect
hb 7, sh 7 no effect

Used phone model for TelloFPV is a Samsung Galaxy S9+
 
FWIW- Re: lag/ delayed response

I decided to give 1.4 Beta a complete workout before I updated to 1.4a so I could compare... using S5 as master and M3 tablet as co-pilot.

Control lag and video was terrible and Tello wandered around like a drunken sailor - until I realized I forgot to turn off Bluetooth on the tablet. Once I did that control response and video was perfect. BT was already off on S5. Also was using on-screen sticks and no external controller.

Just an FYI for anyone having control/video problems - don't forget to use airplane mode on all devices involved, and then turn only Wi-Fi back on. And if you're going to use an external controller, probably best to use OTG (y)
 
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Ok, so these are the results with hb = Heartbeat and sh = Send Handler
hb 6, sh 7 no effect
hb 7, sh 6 no effect
hb 7, sh 7 no effect

Used phone model for TelloFPV is a Samsung Galaxy S9+
Is this with Copilot or without? I assume you also used a BT controller?

Please try to reduce the Video thread priorities (drainer, handler, receiver) to 3 or 4.

If that does not work, can you confirm that it works OK in the 1.3c version (see attached).?



FWIW- Re: lag/ delayed response

I decided to give 1.4 Beta a complete workout before I updated to 1.4a so I could compare... using S5 as master and M3 tablet as co-pilot.

Control lag and video was terrible and Tello wandered around like a drunken sailor - until I realized I forgot to turn off Bluetooth on the tablet. Once I did that control response and video was perfect. BT was already off on S5. Also was using on-screen sticks and no external controller.

Just an FYI for anyone having control/video problems - don't forget to use airplane mode on all devices involved, and then turn only Wi-Fi back on. And if you're going to use an external controller, probably best to use OTG (y)
Have you tried 1.4a with BT on (but without Copilot)?
 

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Have you tried 1.4a with BT on (but without Copilot)?
Not yet, looks like it's going to be tomorrow morning before I can have time to do that. Also want to try it with more than one co-pilot, if I can get my wife to give up her phone for half an hour lol.

BTW what is that attachment in post #2558? It's labeled 13c
 
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When I lost a tello my phone battery was getting low, I was in vr mode and I could see by the bird in the center of the screen that the video feed was delayed but the commands and telemetry were not. I also noticed that if i leave my repeater on the sun and if it gets too hot I'll start having transmission issues. Watch you for that.
 
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Is this with Copilot or without? I assume you also used a BT controller?

It was with Copilot. As I have the test result having no issues without copilot, I now only test with copilot attached how to improve the situation here.
And yes, by default I always have a Gamesir T1d attached as this is my default way of flying the Tello. Therefore I also cannot switch off BT as it was suggested here by someone (ok for a test of course yes, but it cannot be the solution). For myself as a Workaround I potentially could change to a controller that doesn't need BT because it can be connected to the phone via USB (means additional invest as I currently don't own one).
But especcially for the approach I'd like to use the Copilot - using two Gamesirs via BT so that master and student both can have a real controller, the USB controller solution is again out (I don't want to have meters of cable between my phone and the student's controller).

Please try to reduce the Video thread priorities (drainer, handler, receiver) to 3 or 4.

If that does not work, can you confirm that it works OK in the 1.3c version (see attached).?

I will give this a try in the evening and let you know.
1.3c is an older version than the one I received from Play Store?
 
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One more thought regarding Phones and threads.. Maybe it is worth to know that the Samsung Galaxy I think from S6 on is using the bigLITTLE processor pattern. Means you have 8 cores. 4 slower energy saving ones to run non-critical apps or tasks on that can live with lower performance, and 4 strong and power consuming ones for apps and tasks that need more power.
I don't know how your threads are organized and if they are split up among these 8 cores. Maybe it makes a difference if these threads are performed on one of the weak or strong ones (and if it is controllable from the outside or if the phone decides itself to which core it must delegate the thread).
 
Not yet, looks like it's going to be tomorrow morning before I can have time to do that. Also want to try it with more than one co-pilot, if I can get my wife to give up her phone for half an hour lol.

BTW what is that attachment in post #2558? It's labeled 13c
TelloFpv v 1.3c which is the last one before the thread priority changes.

When I lost a tello my phone battery was getting low, I was in vr mode and I could see by the bird in the center of the screen that the video feed was delayed but the commands and telemetry were not. I also noticed that if i leave my repeater on the sun and if it gets too hot I'll start having transmission issues. Watch you for that.
Then it was some power saving mode reducing max thread priority, thus the relatively heavy video processing was the thing that suffered first.
For the repeater & sun problem that is something I never heard before. Could be some freq inaccuracy, or maybe the internal processor of the extender is throttled to reduce temperature load.

It was with Copilot. As I have the test result having no issues without copilot, I now only test with copilot attached how to improve the situation here.
And yes, by default I always have a Gamesir T1d attached as this is my default way of flying the Tello. Therefore I also cannot switch off BT as it was suggested here by someone (ok for a test of course yes, but it cannot be the solution). For myself as a Workaround I potentially could change to a controller that doesn't need BT because it can be connected to the phone via USB (means additional invest as I currently don't own one).
But especcially for the approach I'd like to use the Copilot - using two Gamesirs via BT so that master and student both can have a real controller, the USB controller solution is again out (I don't want to have meters of cable between my phone and the student's controller).



I will give this a try in the evening and let you know.
1.3c is an older version than the one I received from Play Store?
as mentioned 1.3c is the last version before I changed the thread priorities. It already has copilot support, but no threading changes.

One more thought regarding Phones and threads.. Maybe it is worth to know that the Samsung Galaxy I think from S6 on is using the bigLITTLE processor pattern. Means you have 8 cores. 4 slower energy saving ones to run non-critical apps or tasks on that can live with lower performance, and 4 strong and power consuming ones for apps and tasks that need more power.
I don't know how your threads are organized and if they are split up among these 8 cores. Maybe it makes a difference if these threads are performed on one of the weak or strong ones (and if it is controllable from the outside or if the phone decides itself to which core it must delegate the thread).
An app creates threads, both long and short running ones, and assignes priorities. Thats all there is. How each of these threads is mapped to the cores is completely handled by Android.
 
(VPS confusion)
I noticed that after calibrating the compass and using the VGPS the flight path (maximum distance 310 m) is wrong (see image) From the starting point to the maximum distance, there is a level difference of 33 m (measurements taken from Google Earth. Obviously difference in altitude caused problems because once I got home I read a distance of 200 meters.and not "0" mt

Another thing I noticed is that I no longer see the relative red dot in the last position on google maps. is a bug in version 1.4a
 

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Please try to reduce the Video thread priorities (drainer, handler, receiver) to 3 or 4.
Setting these 3 priorities to 3 makes the video stream drop quite often. I had a 10 in brackets at the end (means 10 drops and reconnects afaik). Lags are still there even then. Also tried with increased priorities for heartbeat and send handler again, also no improvement.
Tried also a flight without bt controller and only onscreen controls, this felt somehow a bit better.. Is there maybe a thread that is responsible for reaction on the commands coming in via BT connection? If yes, I could try giving higher priority to that one?

If that does not work, can you confirm that it works OK in the 1.3c version (see attached).?
I cannot reinstall that apk, it fails on attempt (allowed unsafe sources, so that's not the issue).
 
Setting these 3 priorities to 3 makes the video stream drop quite often. I had a 10 in brackets at the end (means 10 drops and reconnects afaik). Lags are still there even then. Also tried with increased priorities for heartbeat and send handler again, also no improvement.
Tried also a flight without bt controller and only onscreen controls, this felt somehow a bit better.. Is there maybe a thread that is responsible for reaction on the commands coming in via BT connection? If yes, I could try giving higher priority to that one?


I cannot reinstall that apk, it fails on attempt (allowed unsafe sources, so that's not the issue).

After installation of the zipped 1.3c i noticed that this is version 1.3b P. and not 1.3c. Are you aware of that?
 
(VPS confusion)
I noticed that after calibrating the compass and using the VGPS the flight path (maximum distance 310 m) is wrong (see image) From the starting point to the maximum distance, there is a level difference of 33 m (measurements taken from Google Earth. Obviously difference in altitude caused problems because once I got home I read a distance of 200 meters.and not "0" mt

Another thing I noticed is that I no longer see the relative red dot in the last position on google maps. is a bug in version 1.4a
Whenever you fly in areas with different ground levels (or high trees, houses, etc) you can expect VPS do do something crazy. No way to compensate for this - its a conceptual limitation because the ground as seen by VPS just does not move as it would expect.

I will check the google maps red dot problem.


After installation of the zipped 1.3c i noticed that this is version 1.3b P. and not 1.3c. Are you aware of that?
Maybe I just grabbed the wrong APK artefact from the database. Not a problem, as it used the same thread priorities.


Setting these 3 priorities to 3 makes the video stream drop quite often. I had a 10 in brackets at the end (means 10 drops and reconnects afaik). Lags are still there even then. Also tried with increased priorities for heartbeat and send handler again, also no improvement.
Tried also a flight without bt controller and only onscreen controls, this felt somehow a bit better.. Is there maybe a thread that is responsible for reaction on the commands coming in via BT connection? If yes, I could try giving higher priority to that one?


I cannot reinstall that apk, it fails on attempt (allowed unsafe sources, so that's not the issue).
What you can try is to increase the heartbeat and sender even more. After that I am running out of ideas and I can only suggest to play with the priorities until you find one that works. If there actually is one that works for your phone, which isn't guaranteed.
I only used my S6 for testing TelloFpv with Controller and a Copilot on S4, but I will try other phones and tablet combinations to see if that makes a difference.

The thread that handles the bluetooth is managed by Android and not under the app's control. No way to change its priorities.
 
Whenever you fly in areas with different ground levels (or high trees, houses, etc) you can expect VPS do do something crazy. No way to compensate for this - its a conceptual limitation because the ground as seen by VPS just does not move as it would expect.

I will check the google maps red dot problem.
thank you I was aware of this ... I wanted to do this long-range test curious to see the behavior of VPS. / VGPS
 
Connection Tello Copilot lost during Photo processing and auto reconnect after.
Some screen interrupts as well
SW Version V1.4b for both Tello FPV and Copilot
This happens with BT and without BT controller (BT switched off).
 
About Heartbeat Settings:
i connect my T1s per cable, is Heartbeat only for Bluetooth devices ?

Greets and save landings
Nope, heartbeat is just that: an essential heartbeat

Connection Tello Copilot lost during Photo processing and auto reconnect after.
Some screen interrupts as well
SW Version V1.4b for both Tello FPV and Copilot
This happens with BT and without BT controller (BT switched off).
Photo download saturates the wifi link with tons of data. Since Tello does this, regardless of reception speed, there is no way to work around this.
 
Green Video.
Hi, I get green screenrecordings on the copilot App. (LG Power X).
But the live Feed Shows only in the First seconds a green Overlay. After that I had a clear fiew in copilot.

In the main App recorded Video the Audio stops and Starts. A few seconds Audio, and for some Frames no Audio

Is it possible that the recorded Video in Main App isnt that Good if I use a copilot App on other Phones?
May be its just a feeling, or simple my new tello didnt Record in Good Quality.
 
Green Video.
Hi, I get green screenrecordings on the copilot App. (LG Power X).
But the live Feed Shows only in the First seconds a green Overlay. After that I had a clear fiew in copilot.

In the main App recorded Video the Audio stops and Starts. A few seconds Audio, and for some Frames no Audio

Is it possible that the recorded Video in Main App isnt that Good if I use a copilot App on other Phones?
May be its just a feeling, or simple my new tello didnt Record in Good Quality.
Nothjng i can so about screen recording. That is just a feature of Android that i use, so if it give bad results its not possible for me to fix.

Yes, the recorded video can be of lower quality. Copilot is not meant to be used while recording
 

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