Raspberry Pi PGenerator Thread

A lot of us regular folk don’t have the skill and experience of Desray and Ronildoq in order to manually calibrate TVs and projectors, myself included. Hence, the advent of AI-based auto calibration software has been a game changer for us. It’s not as simple as press a button and walk away, but with some effort, it lets some noobs get skin into the calibration game without having to study a difficult subject. Furthermore, a lot of TVs and projectors come with internal pattern generators for manual and auto calibration, which greatly simplifies the process. Those who have older TVs need an external pattern generator in order to use calibration software.

External pattern generators such as Murideo Six and AcucPel can cost thousands of dollars and are what professional calibrators use. I started a thread on using an iPhone air playing to an Apple TV 3rd generation to generate patterns for the auto calibration of a 2018 Panasonic TV using Portrait Display’s Calman software. It works. Indeed, Calman has versions for late model Panasonic, LG, Samsung and Sony TVs and projectors. These TVs and projectors can typically be controlled by Calman over an Ethernet IP connection and Calman can adjust their luminance controls and color management systems directly. Saves hours or days compared to changing settings with a TV remote control. Some but not all have pattern generators. So to calibrate a Sony or Samsung, you would need an external pattern generator.

The quality of the calibration depends on a few things, including the quality of the pattern generator and the best pattern generators are “bit perfect”. After all if you are sending a garbage signal into your TV from the pattern generator, your calibration might be garbage too. My iPhone/ATV3 pattern generator is supposedly very good, but not bit perfect. Hence the thought of acquiring or making a bit perfect pattern generator. There are a few other pattern generators that work with Calman using a PC, phone or Amazon Firestick like Lightspace Connect (USD15), but its not clear they are bit perfect or able to output HDR signals properly. The ideal pattern generator should also be able to calibrate HDR and Dolby Vision. Very few pattern generators, even ones the pros use, can actually output HDR, so one stopgap solution is to put a HDFury device like a Linker into the chain, which then can activate HDR via command from Calman.

Fast forward to 2022. It seems that some kind soul on the Internet has written a pattern generator called PGenerator, and the latest version, running on a Raspberry Pi 4, can generate HDR patterns directly and works with Calman over IP. Tests over at AVSForum show that it is bit perfect.

I had been looking at a Pi for a few years, both as an audio streamer, but also to run PGenerator to calibrate my 2018 Panasonic OLED, which does not have an internal pattern generator. However like Nvidia GPUs, Covid disrupted supply chains and Pis’ sold for crazy prices. @Foodie just mentioned that he was looking at doing this over the next few months, which got me looking for a Pi again, and I saw that element14, a Singapore website, is selling the Pi at list price, with a slight backorder. I just ordered one.

Having just finished my MadVR black box, this is a new project. Although the Pi doesn’t arrive until almost month end.

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Thx for starting this thread!

I have a qn. I use 2021 lg oled tv. Using calman home, there is internal PG (iTPG) supported. Both for calibration and meter profiling.

I tot the LG iTPG is reliable for the purposes. But still, some avs experienced calibrators recommends using Pgenerator to both profile the colorimeter and for calibration as they say its bit perfect and LG iTPG may not. How true is this? Surely if big companies like lg collaborate w calman, the iTPG shld be good enough right?

I think the question is whether you are a perfectionist and there are many such people on AVSForum who try to get their Delta Error as close to zero as possible. I suppose for them there are even higher levels of perfection in pattern generators than can be gotten with LG’s pattern generator. Ted’s calibration disc is supposed to have better patterns than any other pattern generator and it seems that many perfectionists pro calibrators on AVSForum agree. Although just happy that I can calibrate with Autocal, I might pay the $30 to get Ted’s version of PGen if it’s better. Eventually I might rerun the 6 hr autocal on my LG projector using Ted’s PGen 1.3 to see if it improves anything.

I’m no perfectionist and at the end of the day, it’s about marginal utility. With a USD1.7k open box laser projector, and a 4 yr old OLED, it’s hard for me to justify spending many thousands on tone mapping or calibration even if I could afford it. I suppose if you have a $20k projector (hint hint), then it’s worth it to get a Murideo for $2.5k or an Envy for $11k. But for me, these home brew solutions get me 90% there, even if I have to lose a few nights sleep and hairs figuring it out :joy:

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Looking fwd to exchange notes and info with u on raspberry + Pgen

Just arrived. My new toy for the next few weeks and months! :laughing:


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We got the same lol

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Nice bro wind. Good to know another person in sg community trying out the PGen

How long have u tried it liao bro?

And… How steep is the learning curve compared to rew ah? :laughing:

This weekend I will attempt setting up the PGen on raspberry the 1st time… :sweat_smile: excited but concerned about the difficulty…

Drool. What a fancy case that Argon One. I got the official blackberry plastic case for $5.73. I like those two full sized HDMI outputs and the fan. Instead, I bought the 2m official micro to full HDMI cable with the blackberry logo :rofl:

I’m glad you and Wind are ahead of me. When I run into problems, I will have two experts to advise me. I will also offer Kopi for copying your fully set up PGen SD card once either of you are finished :grinning:

Avs recommended the argon case, i think its because of the full sized hdmi ports.

Try the argon bro. Quality very good. And u can use normal hmdi cables

Looks like a great case will cooling fan and dual HDMI. I’m planning to use the Pi for service as an audio streamer running Volumio when not used for calibration, so keeping other electronics out of the case may help with reducing electrical noise. It will eventually be run off a linear power supply like my current streamer and DAC.

Sorry for giving the wrong impression bros here. I meant I have the same pi case and pi 4😅 my apology.

I’m currently using the pi4 for dual purpose. 1st is roon bridge for my stereo. 2nd is BEQ for movie.

Oh it can do beq too like minidsp? Is this more for HTPC?

Third purpose will be as Pattern Generator to get a better calibration on your LG Projector :rofl:

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I believe what Wind refers to is to use ezBEQ through Raspberry Pi, which is a very convenient way of setting up BEQ for movies wirelessly, you can search ezBEQ topic in AVSForum.

Thx for this. Oh this is good man.

Ya correct

Got my Pi from another source this evening as I couldn’t wait. I don’t have my case and power supply yet, so running it naked with my MacBook Pro power supply. Downloading Pgen, and flashing it was a bit fiddly, but not difficult. The Pi is now booted off the SD card and now running PGen, but haven’t quite configured it.

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Nice. :+1: U are ahead of me to set it up haha… I had other things to tend to last weekend.

Looks naked. Pamper it w the argon bro. :laughing:

Hope u are allowed to cancel /return the other set too

Picked it up at 6pm and was running Calman by 8pm. The results are much better than using MobileForge with the iPhone and Apple TV on my 2018 Panasonic OLED. Average Delta Error under 1. I’m impressed. The improvement is very obvious in the CIE chart.

Now to work on HDR. Looks complicated.

very interesting, bro Sammy, you triggered my interest to get a raspberry pi again (thought of getting one a few years ago for smart home application, but after getting NAS, dropped the idea), raspberry pi can streaming music, make BEQ loading so easy by enabling ezBEQ (this one will instantly benefit me as I can’t live without bEQ), smart home application (has yet started learning but this is a topic always interests me and I will probably start soon), etc, now even can do auto cal with Calman, worth buying one!