For discussion of topics specific to MythTV on linux
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kbocek
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by kbocek » Mon Oct 07, 2019 3:40 pm
As I mentioned above, I mis-titled this thread. The video mode isn't changing. The option for "separate playback and menu modes" is *not* selected. I verified this at one point, playing some low resolution videos and confirming in the TV that the output was 1080p/60.
I sure hope it's something in Myth. It was starting to feel like a hardware problem. I have two other frontends both with Intel video and they work great.
My monitor section in xorg.conf looks like:
Code: Select all
Section "Monitor"
Identifier "Samsung50"
VendorName "Samsung"
ModelName "Samsung50"
Option "DPMS" "False"
Modeline "1920x1080-1" 148.50 1920 2008 2052 2200 1080 1084 1089 1125 +hsync +vsync
Modeline "1920x1080i-1" 74.25 1920 2448 2492 2640 1080 1084 1094 1125 interlace +hsync +vsync
Modeline "1920x1080i-2" 74.25 1920 2008 2052 2200 1080 1084 1094 1125 interlace +hsync +vsync
Modeline "1920x1080-2" 148.50 1920 2448 2492 2640 1080 1084 1089 1125 +hsync +vsync
Modeline "1920x1080-3" 74.25 1920 2558 2602 2750 1080 1084 1089 1125 +hsync +vsync
Modeline "1920x1080-4" 74.25 1920 2448 2492 2640 1080 1084 1089 1125 +hsync +vsync
Modeline "1920x1080-5" 74.25 1920 2008 2052 2200 1080 1084 1089 1125 +hsync +vsync
EndSection
The modelines were extracted from the X autoprobe output. On my other frontends, X will add the manual lines to this list of autoprobed modelines in Xorg.0.log. Somehow here my created "-1", "-2" identifiers are not showing up so I can't select them in my screen section.
Not sure what to do now.
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blm-ubunet
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by blm-ubunet » Mon Oct 07, 2019 8:18 pm
I calculated the refresh rates for each of your listed 7 modes:
60 p
25 i
30 i
50 p
24 p // should be 23.976 additional
25 p ?
30 p ?
All above numbers are exact integer values (to 3dp).
Can't comment on the validity of the sync polarities.
They appear to be mix of std computer modes but not exact video modelines.. did they come out of a TV EDID ?
Maybe some are rejected because they are parsed and seen as repeats & plain wrong &/or outside acceptable V & H sync bands.
Can't see any use for 25p & 30p.. 24p (23.976) is bad enough.
Should never need to output interlaced video, make video card do it. If it can't then replace with something fit for purpose.
And should always use reduced vertical blanking timing if possible.
So replace all of them with the output from this:
cvt -r 1920 1080 60 // 1920x1080 59.93 Hz right TV/video mode.
&
cvt 1920 1080 50 // 50p no RVB
cvt -i 1920 1080 30 // if you really must have interlaced. not exact refresh rate (modify -r 60 modeline?).
Sadly, the FOSS modeline calculators do not understand the reduced blanking timing & exact video timings for 24 & 50Hz or any interlaced mode.
But all modern displays work with reduced blanking timing.
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kbocek
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by kbocek » Tue Oct 08, 2019 3:58 pm
So the calculated modeline is:
Code: Select all
Modeline "1920x1080R" 138.50 1920 1968 2000 2080 1080 1083 1088 1111 +hsync -vsync
I added this to my monitor section and commented out the others. However after rebooting I do not see "1920x1080R" anywhere in Xorg.0.log. Any thoughts on why?
I wasn't expecting to use an interlaced mode. I just wanted to try everything and see if it would fix the problem.
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blm-ubunet
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by blm-ubunet » Tue Oct 08, 2019 6:35 pm
I would guess that the whole file is being ignored due to syntax erorr or missing semantics.
The log file should indicate that your xorg.conf is be opened.
The documentation on xorg.conf is very dated except for Nvidia & that most likely does not apply.
I use custom modelines but on Nvidia hardware.
Attached an example of Nvidia xorg.conf file (/etc/X11/xorg.conf.d/20-nvidia.conf)
Code: Select all
# 20-nvidia.conf
# nvidia-settings: X configuration file generated by nvidia-settings
Section "Modes"
Identifier "myHDTV"
# 3840x2160 23.99 Hz (CVT) hsync: 52.59 kHz; pclk: 266.75 MHz
Modeline "3840x2160_24.00" 266.75 3840 4056 4456 5072 2160 2163 2168 2192 -hsync +vsync
# perfect 50Hz mode, reduced vertical blanking period
# 3840x2160x50.000 @ 110.500kHz
Modeline "3840x2160_50.00" 442.000 3840 3888 3920 4000 2160 2163 2167 2210 +HSync -VSync
#3840x2160 p59.940 rvb
Modeline "3840x2160_59.94" 532.75 3840 3888 3920 4000 2160 2163 2167 2222 +hsync -vsync
Modeline "3840x2160_75.00" 904.00 3840 4168 4592 5344 2160 2163 2168 2257 -hsync +vsync
EndSection
Section "Monitor"
# HorizSync source: edid, VertRefresh source: edid
Identifier "Monitor0"
VendorName "Unknown"
ModelName "Philips PHL BDM4350"
HorizSync 30.0 - 160.0
VertRefresh 23.0 - 80.0
DisplaySize 953 543
Option "DPMS"
UseModes "myHDTV"
Option "PreferredMode" "3840x2160_50.00"
EndSection
Section "Device"
Identifier "Device0"
Driver "nvidia"
VendorName "NVIDIA Corporation"
BoardName "GeForce GTX 1050 Ti"
# Option "ForceFullCompositionPipeline" "DFP-2"
EndSection
Section "Screen"
Identifier "Screen0"
Device "Device0"
Monitor "Monitor0"
DefaultDepth 24
Option "Xinerama" "0"
Option "TwinView" "0"
Option "DefaultServerLayout" "Layout0"
Option "NoLogo" "True"
Option "ModeDebug" "True"
Option "SLI" "Off"
Option "MultiGPU" "Off"
Option "BaseMosaic" "Off"
Option "ConnectedMonitor" "DFP-2"
Option "UseDisplayDevice" "DFP-2"
Option "ConstantDPI" "False"
Option "UseEDID" "False"
Option "ModeValidation" "DFP-2: AllowNonEdidModes, NoEdidModes, NoVesaModes, NoXServerModes, NoPredefinedModes"
Option "ColorSpace" "DFP-2: YCbCr444"
Option "Stereo" "0"
Option "nvidiaXineramaInfoOrder" "DFP-2"
SubSection "Display"
Depth 24
Modes "3840x2160_50.00 ; 3840x2160_59.94 ; 3840x2160_75.00 ; 3840x2160_24"
Option "PreferredMode" "3840x2160_50.00"
EndSubSection
EndSection
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kbocek
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by kbocek » Thu Oct 10, 2019 4:08 pm
No it's being read. My monitor identifier "Samsung50" as well as the specified Intel driver settings are present in Xorg.0.log. Just not the custom mode lines.
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kbocek
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by kbocek » Mon Oct 14, 2019 3:07 pm
Yes I played with xrandr. When the screen went blank, I found I could bring it "alive" again by switching to another resolution. Sadly, switching back to 1080p/60 *still* didn't work.