Which reason can lead to screen tearing on Tx1

Hi, all

Tearing is a very annoying problem when you show your camera captured video on screen,

because we totally have no concept about it and don’t know which reason leads to it.

We use Tx1 module on a custom board with driver package 24-2-1.

[u]Tearing is appeared when our openGL app displays 6 camera captured videos at the same time on

different area of the screen.Each camera captured video is set to 1920@1080 resolution in driver.[/u]

It’s also happened when just a single camera captured video displays on the screen.

I doubt that it is a little difficult to process 6 csi capture at the same time for tx1.

Or it is just improper code which we write with openGL lead to the problem.

Can you give me some directions to search the root cause ? thanks in advance.

[b]Maybe many causes can lead to tearing,software (driver) or hardware. How can I distinguish them and

find the correct solution?[/b]

Hi anhuimain,

If you open only one camrea, would the tearing problem still show?

Hi, WayneWWW

It’s not always tearing on the screen when just open only one camera.

It‘s appeared sometimes when the system has run for a period of time(5 hours or more).

We don’t use fan to cool the Tx1 module and just put a heat sink on the module.

I doubt that it contributes to the tearing.

I can’t be sure.

Please share your sample code for us to reproduce the issue if possible.

You mention some thermal design, so you are not using original tx1 devkit,right?

If this affects GPU performance, then it is possible causing tearing.

Hi,WayneWWW

We use custom board with software which is downloaded by JetPack-L4T-2.3-linux-x64.run.

We have not just one custom board,another custom carried board of Tx1 does not produce tearing on

the screen when just open one camera ,even two. The comparison is not proper, because the app and driver

are not the same.

BUt open six camera at the same time is the first time of try.

I think thermal design is the last thing to consider, because it is a large work. My conclusion on comment #3 is just a guess.

At first , I want to get some hint in software (openGL or driver).

If it is not solved, I will offer the data measured at the same condition for parsing.

Hi anhuimain,

We indeed have a bug related to tearing problem when using openGL, but it only happens on dual monitor case. Are you using multiple monitors?

Also, just a suggestion, lots of patches have been added to rel-28.1 and latest rel-28.2. Please update to rel-28 if there is no production need.

Thank you for your patient answer.

No,we are not using multiple monitors. But I learn that tearing on dual monitor can dispear by 

replacing ubuntu desktop(gnome) with Cinnamon (lxde may be OK).

I am trying to do a serial of reasonable test and going to have a try of your suggestions.