[mythtv-users] MythTV Raspberry Pi 2+ MythFrontend Setup Tutorial Updated

Curtis Gedak gedakc at gmail.com
Wed Mar 16 01:08:54 UTC 2016


On 16-03-15 04:10 PM, Ben Healy wrote:
>> From: Curtis Gedak <gedakc at gmail.com>
>> To: mythtv-users at mythtv.org
>> Sent: Wednesday, 16 March 2016, 3:05
>> Subject: Re: [mythtv-users] MythTV Raspberry Pi 2+ MythFrontend Setup Tutorial Updated
>>
>> ...<snip>
>> I think I may have a solution that will work for all monitors.
>>
>> ...<snip>...
>>
>> Following is the group of settings I discovered:
>>
>> /boot/config.txt
>> ----------------
>>
>> hdmi_drive=2 # Normal HDMI mode (Sound will be sent if supported and
>> enabled)
>> hdmi_group=2 # DMT
>> hdmi_mode=39 # 1360x768 60 Hz
>>
>> I live in Canada with 60 Hz AC power.  I'm not sure if a different mode
>> is needed for those in countries with 50 Hz AC power.
>>
>> Mythfrontend Settings
>> ---------------------
>>
>> Use the mythfrontend *Setup -> Appearance* menu to alter the *GUI width
>> (pixels)* and *GUI height (pixels)* values to match the resolution you
>> chose for /boot/config.txt.
>>
>> GUI width (pixels):  1360
>> GUI height (pixels):  768
>> GUI X offset:           0
>> GUI Y offset:           0
>> ...<snip>
> 
> Hi Curtis
> 
> I think this probably works as 1360x768 is more of a PC resolution than video resolution, so many TVs will automatically display it with no overscan.
> 
> The problem that may arise is that it will usually only work with 60Hz refresh rate, meaning that 50Hz, 24Hz etc content won't be smooth.
> 
> This is not so much a problem if you live in a 60Hz country and mainly use Myth to watch TV, but if you live in a 50Hz country or watch a lot of movies that are 24Hz you may notice the video not smooth.
> 
> I would think that 1920x1080 would be the best resolution as most TVs would support 60Hz, 50Hz and 24Hz at that resolution.
> 
> 
> More details are at:
> https://www.mythtv.org/wiki/User_Manual:JudderFree
> 
> I have had this config working on nvidia and intel frontends, but so far I haven't got it to work on the Raspberry Pi in MythTV (Peter's build).
> 
> Dynamic refresh rate switching does work on the Raspberry Pi on Openelec and OSMC.
> 
> Ben

Thank you Ben for this link.

At your suggestion of 1920x1080 at 60 Hz I tried the following settings:

/boot/config.txt
----------------

hdmi_group=1 # CEA
hdmi_mode=16 # 1080p  60 Hz

I live in Canada with 60 Hz AC power.  Per your suggestion I think users
in countries with 50 Hz AC power will need to replace the above
hdmi_mode with:

hdmi_mode=31 # 1080p  50 Hz

Mythfrontend Settings
---------------------

Use the mythfrontend *Setup -> Appearance* menu to alter the *GUI width
(pixels)* and *GUI height (pixels)* values to match the resolution you
chose for /boot/config.txt.

GUI width (pixels):  1920
GUI height (pixels): 1080
GUI X offset:           0
GUI Y offset:           0


With these settings and an non-overclocked RPi2 I observed the following:

Non-overclocked RPi2
--------------------
720p content played reasonably well with rare stutters in video/audio.
1080i content would occasionally stutter and there would be gaps in the
audio.


Next I applied the following overclock settings.

# Overclock settings
arm_freq=1000
core_freq=450
gpu_freq=300
sdram_freq=467
over_voltage=2

Overclocked RPi2
----------------
720p content played well with smooth video and clear sound.
1080i content still suffered the occasional stutter and gaps in audio.

It would appear that 1080i 60 Hz content is near the limit of what an
RPi2 can handle at 1080p 60 Hz screen resolution.


Perhaps someone with a Raspberry Pi 3 could perform additional testing
to see if the RPi3 is up to the task.

Curtis


More information about the mythtv-users mailing list