[mythtv-users] Raspberry Pi 3 Mythfrontend

[Brian Knapp]

Please bear with me, as this is my first ever "mailing list" post.  I wanted to share my experiences with others who are considering the Raspberry Pi 3 as a mythfrontend and post my progress and a place for us to share our experiences/feedback.  Feel free to ask me to try anything that you would like me to try.  Just be patient as I have a very limited amount of time as you might notice by the several nuisances that I haven't gotten around to trying to resolve.  The long and short of it is that the playback has been very respectable.

I mainly followed Curtis' guide for setting up mythfrontend on a Raspberry Pi.  I started with flashing the SD card with Raspbian build: 2016-04-03.  I setup the wifi on the Raspberry Pi 3 instead of using a wired connection.

Initially I installed Peter's .deb package of mythtv light, build: 0.27.6-79-g7d7b431-0 because it was newer than Lawrence's tarball.  I found that I had to install mysql server and setup a mythtv mysql user on the raspberry pi or it would asked for my locale settings every time that I ran mythfrontend.  Once I got into the settings, I realized that I could not select opengl in this build, so I since installed/untar'd Lawrence's build: mythtv-v0.27.6-69-g41a2a8d

I have had very limited testing thus far, and virtually no time to troubleshoot.  What I am finding is the following, using my 7-8 year old Dynex DX-LCD42HD-09 with HDMI for video and audio:
1. I had to disable DTS and Dolby Digital in my mythfrontend audio settings or the audio was basically stuttering static.
2. XCB using the OpenMAX Normal profile playback was very good, but video was shifted up and left.  Overscan settings within mythfrontend do not seem to help.  I have not done any troubleshooting with overscan in /boot/config.txt, though.
3. A script to autostart XCB mode fails because of X permission issues.
4. EGLFS using OpenMAX EGLFS results in video/audio stutter every few seconds.  Perhaps I need to look at audio settings again?
5. EGLFS using OpenMAX Normal profile gives me my best results.  I can autostart this on boot and the video is not shifted at all.  There are some overscan issues on the display when in the menus, but I do not notice them in the video playback.  mythfrontend overscan settings still do not have any effect, and I still have not tried /boot/config.txt settings.
6. I have not installed a remote.  I have remotes in storage, just no IR receiver.  I am debating whether to do the homebrew IR receiver I have seen online or try to get a bluetooth solution (or I just downloaded an Android mythfrontend remote app that I haven't tried yet).  Having said all of this, when I use EGLFS, it appears that my keyboard keypresses are also passing back to the shell.  I have noticed a lot of prompts with no text and bizarre text, I presume from pressing enter in mythfrontend and other keys during video playback.
7. I installed the MPEG-2 license, but I don't know how necessary it was.  I initially thought it was responsible for my audio issues in item (1), but that was not the case.
8.  It is important to ensure that GPU memory is set to 256.  I tried enabling the testing opengl in rpi-config and I think it may have reverted it to a lower value.  It then took me quite a while to figure out why video playback kept failing.  Also, when I tried OpenMAX EGLFS with the testing opengl I got a hard lockup.  I have disabled the testing opengl and not gone back to verify the GPU memory with it on to see if that would correct anything.
9.  I've noticed that at least the last couple times that I have exited mythfrontend in EGLFS mode, it does not exit cleanly.  I have not seen Curtis' issue yet where mythfrontend remained on the screen.  In my case it goes back to the shell and says something like waiting for threads to close (or maybe something totally different, but it never seems to finish so I have to ctrl+c to get back to the prompt.
10. I let the frontend go idle once.  It seemed to disconnect from the backend and allow it to shutdown automatically, and the backend was back online when I brought the frontend out of standby, but it decided to reboot the raspberry pi.  I'm not sure if there is just a default setting on the frontend that I need to review.

FYI, my backend is a full PC running LinHES R8.1 which is running mythtv 0.27 on Arch Linux and an HDHomerun Prime tuner.  It has probably been running smoothly for over 2 years, so I will have forgotten pretty much any configuration that I would have done to get it to the point it is at now.