QML Camera autofocus weird behaviour for ffmpeg backend

My app is using QZXing as QRCode decoder. I have the issue that the camera does not focus properly on IPhone Pro models with backend darwin and setting focusmodeautonear and with ffmpeg IPhone 13 also does not focus.

Currently I have a Test running with Qt 6.5.7 focusmodeauto and backend darwin where i set tryHarder on QrCode decoder. In the latest tests it seems that the QrCode is recognized well on IPhone Pro models and I-Pads. 

IOS

Qt 6.5.3 darwin only:

• IPhone 13 IOS 17.5 setting different focusmodes camera is not focussing at all but when QrCode is sharp whithin the viewport, the QrCode can extract its content
• IPhone 14 pro IOS 18.01 setting different focusmodes camera is not focussing at all but when QrCode is sharp whithin the viewport, the QrCode can extract its content
• IPad 9th IOS 18.01 generation camera is focusing and reading of QrCode is easy

Qt 6.5.7:

• IPhone 13 IOS 17.5 camera seems to focus but QrCode is not recognized... The image is blurry and not sharp in the viewport (ffmpeg / darwin)
• IPhone 14 pro IOS 18.01 (darwin) the QrCode is perfectly recognized, camera is sharp using focusmodeauto, ffmpeg QrCode is not recognized
• IPad 9th generation IOS 18.01 (ffmpeg) camera is focusing and reading of QrCode is easy using focusmodeautonear

Seems that the models with only 2 backcameras have a problem to autofocus.

Android
Qt 6.5.3: 

• Camera is not working properly, there was a bug in this release not using in my app

Qt 6.5.7:

• Backend "android" autofocus is working on different device, backend "ffmpeg" not autofocus recognized through all my tests

Conclusion for me is to stick with Qt 6.5.3 and darwin for ios and Qt 6.5.7 for android. This is a really annoying think for building and publishing! Qt 6.5.7 seems to be the better version in all matters but the Multimedia part is really a hard thing since Qt 6. Qt 5.15 things were working really smooth on all platforms...

More information from other devs: https://discord.com/channels/457523061650882570/1017293587815337994