Ipad mini 4 64gb video freezes

[Webnit]

Hello all. I have been an avid drone pilot for years. I started with a P3P and have a P4P more recently. I had always used an android phone (note 4 or 5) and even a tablet 4 10" which were all flawless. I had acquired a Ipad mini 4 64gb w/cellular because I had heard discussions about the screen brightness in daylight. I tried to use it on my P3P early on and ran into issues of the screen freezing in flight or slow updating on the live feed. This became a safety issue that I never experienced with my android devices. I even pulled it out to use on my P4P and had the same issues.

Is there some special settings needed to use it on any of these drones? I'm happy to use my android devices which have been excellent, but its something that's never been solved.

Thanks for any advice!

 

[Nightjumper6mike]

I have the same problem with my iPad Mini 4 128gb with cell & wi-fi. My iPad Pro works just fine, but the mini screen keeps flipping a green screen during videos. I have no idea what setting I have wrong.

 

[John Locke]

Look for hardware decoding and enable it. That might be the cause. Note, this has been removed from the latest GO4 app I heard, it's always enabled in the latest version if that's what you're using.

This could also be Wi-Fi interference, so try switching to 5.8Ghz in P4P, or as last resort set to a custom channel with low traffic showing in the HD traffic monitor.

 

[Nightjumper6mike]

Where do I find "hardware decoding"? On the iPad device or the drone?

 

[Nightjumper6mike]

It is now flashing "Mobile device CPU fully loaded". So how do I unload it? Help!

 

[John Locke]

Where do I find "hardware decoding"? On the iPad device or the drone?

It's in the GO4 app, assuming you're not using the latest version which removed it, with it always on.

 

[Nightjumper6mike]

I'm using the latest version. Bummer!

 

[shockwave199]

Try factory default on that iPad. It should work perfectly fine. Delete the go app and reinstall in the process. Disable video cache and bring down the live feed bit rate to 4 or 6mbs if problems persist. But it seems that ipad needs a fresh start and start again. Also consider the cable you're using and try another.

 

[Nightjumper6mike]

That's scary, a full wipeout and restart, but I'll give it a go. Tnx

 

[shockwave199]

Well don't do it if you don't want to. I'm not an iPad expert by any stretch. Just a suggestion. I'd be less likely to do it if I was entrenched in personal settings in the tablet that I didn't want to lose. But if you don't use it for anything else and it's just sitting there it could make sense to try a reset.

 

[Nightjumper6mike]

OK, I reset the iPad Mini 4 to its birth. I'll find out tomorrow what good/damage I've done. Not tech at all and the word reset scares me.

 

[Nightjumper6mike]

I'm currently online with expert help.com. Paid $57 for "urgent help" and have been on hold for over 30 min! I have no choice but to wait. Don't fall for it.

 

[Nightjumper6mike]

It appears the CPU in my Mini 4 isn't fast enough for the latest DJI Go 4 app update. My iPad Pro works just fine, so I'm trading in the Mini 4 for another Pro tomorrow as I need a dedicated device for the drones

 

[photoskyview]

In the DJI Go 4 in the HD settings select custom, select the 20 channel, 4 or 6 mbps and that settings works for me.

 

[Nightjumper6mike]

Been there, done that. I've tried from 4mbps to 10mbps and all in between. No difference. It boils down to my CPU just isn't fast enough on my Mini 4. iPad Pro works fine.

 

[shockwave199]

There's a ton of mini 4 users that would beg to differ with it not being able to run the app. Not sure why yours can't.

 

[Webnit]

Blew it away back to factory default, reloaded apps and turned caching off, went down to 4mb. Seems to have worked. Thanks all.

 

[shockwave199]

Good lord, I didn't even realize I wasn't talking to the OP all this time. Glad it worked out for YOU!

 

[vsc]

Not all Apple iOS devices provide a thermal conduction path from the CPU to the case. Apple employs throttling to protect the CPU under high work loads, such as decoding video on the ARM. Throttling lowers clock rate to manage thermal dissipation to a safe level. The iPad Mini (all versions) are examples of devices which do not provide the thermal conduction path, thus ambient temperature is a factor especially with summer temperatures.

The result when throttling occurs is that the CPU cannot keep up with the video stream, effectively dropping H.264 packets. Dropped packets with respect to a H.264 stream presents as blocky, tearing and/or green sections of the display. Note a dropped packet can occur due to a lack of data link closure (e.g. range, interference, etc) or simply the queue is full and packets are dropped on the floor.

Unfortunately there is little information on the web with respect to this issue, though the person in the following thread aggregates a number of sources to show this problem and which devices are affected.

IOS Devices and Pilot App Thermal Throttling. - RC Groups

In my case I have access to Samsung devices and tested a Tab S2 (SM-T710 and SM-T713). Both have zero issue with playing back a video stream under thermal stress, though the 713 has a USB linking issue documented elsewhere. I purchased the 713 for dedicates use with the P4P where the linking workaround is manageable especially given the low cost of the Tab S2. In the field I let the Tab S2 using my iPhone's access point to provide connectivity, where my iPad has cellular built it. Thus on the Samsung not integrated, but workable.

My impression is that Apple decided portable battery operated operation is not consistent with high work loads which result in excessive battery consumption, limited battery endurance and ultimately higher manufacturing cost to include a thermal path. If Apple is a must then review the thread cited above. Otherwise there are alternatives.

 

[Nightjumper6mike]

I do believe heat might have been an issue as the sun here gets really hot and the flipping seems to start after some time into flight. Thx for help.