Magic mirror with RPI 4?



  • This may be a dumb question, but is there any difference between using a raspberry pi 3b+ or a 4GB raspberry 4? The pi 4’s are on sale near me, so I bought one today for my gaming console/kodi box, but I’m thinking of grabbing a second one to start programming the magic mirror. I just want to make sure that everything still sets up and runs properly on the newer model.

    Does size matter in this case? There is only a $5 difference between the 2GB and the 4GB pi 4’s near me, so it makes sense to grab the 4GB… but does it make a difference in the end?

    Lastly… does it make much of a difference if I use a tv instead of a computer monitor? I’m hoping to make my mirror a bit bigger than the average computer screen (32" if I can source the glass affordably, otherwise I’ll move down to a 27" gaming monitor)



  • @Mrr the 4 is faster and has more memory, so less swapping in large solutions. but it doesn’t matter

    I have 2 pis, 0 and 3b+
    2 odroid XU4’s,
    1 Jetson Nano
    2 desktop systems running ubunu
    2 virtual machines, 1 ubuntu 19.10, and one Mac catalina

    I use a tv for my main display, 55in 4k (only the jetson does 4k) (use all 4 inputs)
    One of the odroids is a photoframe on a 32in tv

    both TV’s do NOT turn off by command. so I have a module that hides all the modules
    and uses motion detection from camera to wake up

    size only matters in the case u build, if any, but all these are so small, you shoudn’t have a problem



  • I’ve noticed a significant improvement in launch speed, but otherwise, there’s no difference from my RasPi 3 to RasPi 4.

    Make sure to get the additional hardware with it - it’s using a USB-C plug now, and miniHDMI ports, so you’ll need an adapter for that.



  • @BKeyport oof, I completely forgot about the micro HDMI adapter. I guess I can’t get far without that

    @sdetweil so essentially a tv screen makes no difference other than requiring a bit more configuration? I discovered that a friend of mine works with glass and can get me a cheap sheet suitable for a 42" tv screen, so I’d love to go bigger than a computer monitor. My last question (for now), is does it matter what type of tv I use? I’m looking at some older, second hand ones, but I don’t want to spend the money if it won’t work. Do they need to be relatively newer models?



  • @Mrr the mirror assumption is a 16:9 screen… you can adjust that in the css tho…

    i found a new 55in 4k tv for $219 about 2 months ago… awesome picture rendition!
    i have a different pi/sbc connected to each of the 4 hdmi inputs… (yeh, I’m sort stuck on this stuff!)

    my MM photoframe is a 32in Roku Tv mounted on the wall in the hall… (no mirror glass)



  • @sdetweil out of curiousity, what do the 4 different pis/sdc do on the tv?

    I’m extremely new to this (my only experience with rpi being the basic retro gaming console with Kodi), so excuse my ignorance here, but I’m assuming that most new tvs have the 16:9 aspect ratio?

    What modules do you recommend using for a tv magic mirror? (In terms of having it wake up/go to sleep)… I’ve heard that the most annoying thing with using a television is that it will often go to the “no signal” screen when not in use, and I’d like to avoid this if possible



  • @Mrr yes, anything in the last 15 yrs (maybe more) has been 16:9

    i have a jetson nano on one port, an odroid XU4 on another, PI 3b+ and a pi 0 W on the last…

    gives me options to try different things… (I just updated the installer module to cover a lot more systems)
    see https://forum.magicmirror.builders/topic/10171/anyone-want-to-try-updated-installer

    and a new script for update, which happens frequently (quarterly)
    https://forum.magicmirror.builders/topic/10859/new-update-upgrade-script-ready-for-testing

    and I have my own stuff I write and modify

    as for the tv no input problem, I ended up writing my own module MMM-SleepWake.
    that supports a webcam for motion (no PIR sensor here at the time), and it will blanks the screen… (hide all the modules)…

    not completely dark, no power saving… but it works…

    uses an installable OS module (apt-get install motion) to connect to the camera ( more than I wanted to learn) so ANYTHING can be used to drive SleepWake as its all file notice based…



  • Thanks for the links @sdetweil, I’ll toy with it a bit once I get my screen this weekend and hopefully I can come up with something. I wish they made larger computer monitors, as that seems to be the best to work with, but oh well! I feel like the extra work that a tv monitor takes is probably worth it to have a bigger mirror in the end hey?

    You’ll likely be seeing me around with a ton of questions in the coming weeks as I try to figure this out



  • And also, just to confirm… the type of tv that I use doesn’t make a difference, correct?

    I’m looking to pick up a second hand 50" from someone off Craigslist. Its a flat screen but I’m not sure how old. Are there any specific things that I should look for in a TV monitor? I know one thing that was mentioned was to look for one that has the HDMI ports on the side, but anything else?



  • @Mrr correct… doesn’t matter… I started with a 50 in , non-4k from craigslist in 2016. just replaced recently with the 55…

    I have a 32 in in the hall (the largest photoframe I could find was 24in, and $400… so for $110 including the pi, I made a 32 in FF. connected to my local lan linux server (actually the pics are all on an external 5tb drive)