[Android Software Development] spocky12:
Second post to explain a few related things that happened lately.

Some of you might know the web site Passion Home Cinema, a french site that tests many projectors (in both french and english). In the last few monthes, Gregory tested the Mijia 4k, the Fengmi Cinema 4k and the Wemax A300 (each time, english text is available in the same page, in the second part of the test).

Tested Fengmi and Wemax were sourced from an Australian reseller, https://nothingbutlabel.com/, who proposes both stock and rooted versions. Tested versions were the rooted ones.

A few days ago, Gregory tested the Wemax A300 a second time, but this time with a stock version from gearbest. In his description, he opposes the australian rooted version and the stock chinese one. He comes to the strange conclusion that if the rooted version has better color calibration and gamma out of the box, the stock chinese version, once manually calibrated, has better dynamics and color strength.

I say "strange" because rooting the projector, replacing the launcher and freezing apps have absolutely no relationship with color calibration. My tools don't change in any way any low level settings or display drivers. And the settings you can change through the app (such as the noise reduction), have to be reapplied after power off.

So I came to the only possible conclusion : the visible differences were not due to root or google apps, but to a difference of firmwares. Both Wemax and Fengmi are sold with build 494, and both have an update to build 536, which incidentally changes files related to image calibration. So that totally makes sense.

I know for a fact that the tested rooted version was using build 536. I'm still waiting for the answer concerning the gearbest version, but I don't see them updating their devices before expedition, so I believe it was using stock build, 494.

If you're following me so far, this means that according to Gregory's tests, and reading between the lines, build 494, once calibrated, offers better image than build 536 (which has the advantage of offering good out of the box calibration). At least on Wemax A300. How is this possible ? Because, the fine grained calibration plays on a massive number of parameters (not available in the settings) to adjust the gamma PQ curve, coming in a sqlite database, that once applied, can change to behavior of your device (ie : the same "high level" display settings such as contrast, brightness... will display differently when a different PQ calibration is applied).

What can we conclude from all this : no matter where you buy your device, image differences are due to the firmware installed on them. And you can of course install whichever you want.

Seeing how it spread quickly on multiple forums, I decided to address the "issue" : since a few hours, Batman owners can use their current version of Mi ProjecTivy Tools to change the PQ calibration to 494 or 536 and compare by themselves. No need to downgrade/upgrade firmware :D. Just head to "Install third party apps", and at the bottom of the list, you'll find "Projector PQ calibration b494" and "Projector PQ calibration b536". Just install and reboot.

Now let's address the last point : the australian shop, nothingbutlabel. They contacted me a few monthes ago to offer me a deal : they use my work to root their projectors and in return, they donate a few dollars for each sold projector to thank and encourage my work. They could have done this totally without my approval, and they never asked me to advertise this "partnership" anywhere (which I never did), so I believe this proves their honesty. We also regularly exchange by email. So if you want to buy from their shop, you can trust them, they won't add spywares or any kind of other nasty things to the rooted devices they sell.

Guess I've caught up on everything, that'll be all for today :)