CentOS - Apr 2020 - Strangeness on X11 screen capture

Hi all,

I am running CentOS 7 on a NUC5CPYB. Intel video:
00:02.0 VGA compatible controller: Intel Corporation Atom/Celeron/Pentium
Processor x5-E8000/J3xxx/N3xxx Integrated Graphics Controller (rev 35)


When I take a screen shot I get "different" things.
I use:
export DISPLAY=:0.0
/usr/bin/xwd -silent -root -out screen; convert screen screen.png

I tried import also for the screen capture and its the same random images.

Granted the images are all things I have showing previously - but most
times its not what is showing now.

I have verified the Intel driver is loaded:
[    19.009] (II) LoadModule: "intel"
[    19.010] (II) Loading /usr/lib64/xorg/modules/drivers/intel_drv.so
[    19.012] (II) Module intel: vendor="X.Org Foundation"
[    19.012]    compiled for 1.20.1, module version = 2.99.917
[    19.012]    Module class: X.Org Video Driver
[    19.012]    ABI class: X.Org Video Driver, version 24.0
[    19.012] (II) intel: Driver for Intel(R) Integrated Graphics Chipsets:
        i810, i810-dc100, i810e, i815, i830M, 845G, 854, 852GM/855GM, 865G,
        915G, E7221 (i915), 915GM, 945G, 945GM, 945GME, Pineview GM,
        Pineview G, 965G, G35, 965Q, 946GZ, 965GM, 965GME/GLE, G33, Q35,
Q33,
        GM45, 4 Series, G45/G43, Q45/Q43, G41, B43
[    19.015] (II) intel: Driver for Intel(R) HD Graphics
[    19.015] (II) intel: Driver for Intel(R) Iris(TM) Graphics
[    19.015] (II) intel: Driver for Intel(R) Iris(TM) Pro Graphics
[    19.015] (++) using VT number 1

[    19.016] (II) intel(0): Using Kernel Mode Setting driver: i915, version
1.6.0 20181204
[    19.018] (--) intel(0): Integrated Graphics Chipset: Intel(R) HD
Graphics
[    19.019] (--) intel(0): CPU: x86-64, sse2, sse3, ssse3, sse4.1, sse4.2;
using a maximum of 2 threads
[    19.019] (II) intel(0): Creating default Display subsection in Screen
section
        "Default Screen Section" for depth/fbbpp 24/32
[    19.019] (==) intel(0): Depth 24, (--) framebuffer bpp 32
[    19.019] (==) intel(0): RGB weight 888
[    19.019] (==) intel(0): Default visual is TrueColor
[    19.023] (II) intel(0): Output DP1 has no monitor section
[    19.024] (II) intel(0): Enabled output DP1
[    19.024] (II) intel(0): Output HDMI1 has no monitor section
[    19.025] (II) intel(0): Enabled output HDMI1
[    19.025] (II) intel(0): Output DP2 has no monitor section
[    19.026] (II) intel(0): Enabled output DP2
[    19.026] (II) intel(0): Output HDMI2 has no monitor section
[    19.027] (II) intel(0): Enabled output HDMI2
[    19.027] (--) intel(0): Using a maximum size of 256x256 for hardware
cursors
[    19.027] (II) intel(0): Output VIRTUAL1 has no monitor section
[    19.027] (II) intel(0): Enabled output VIRTUAL1
[    19.028] (--) intel(0): Output HDMI2 using initial mode 1920x1080 on
pipe 2

What can be doing this ? How do I track it down?
Thanks,

Jerry

On Thu, 16 Apr 2020, Jerry Geis wrote:
> When I take a screen shot I get "different" things.
> I use:
> export DISPLAY=:0.0
> /usr/bin/xwd -silent -root -out screen; convert screen screen.png
>
> I tried import also for the screen capture and its the same random images.
>
> Granted the images are all things I have showing previously - but most
> times its not what is showing now.
My guess is that it the result of applications,
e.g. video players, that bypass X.
xwd reads the appropriate buffers,
but those buffers are not what is on the screen.

-- 
Michael   hennebry at web.cs.ndsu.NoDak.edu
"Sorry but your password must contain an uppercase letter, a number,
a haiku, a gang sign, a heiroglyph, and the blood of a virgin."
                                                              --  someeecards

Thanks Michael

I have been using electron-kiosk -  Would that be contributing to the
situation?
I have been playing videos - we pages etc...

Any thoughts on something to help get the right picture ?

Jerry