Bug-Report: VLC sets wrong conversion mode when switching renderer

[CO_Windler]

I found a very confusing bug in VLC (on Linux or Win10). Switching the video output mode (dropdown menu) first time from "automatic" to any others will start to convert videos with a terribly blocky pixelated renderer. You CAN NOT simply switch back to make the original conversion mode work again.

Apparently in menu the button "x264v preset and tuning selection" (showing "ultrafast") is initially ignored but gets set when video output is not "automatic" anymore, and this setting stays active even after switching back. That's what ruins transcoding. The solution is to manually select "slow".

(The downside of the original hardware renderer on my Linux Mint (AMD Ryzen 2400G APU with updated amdgpu drivers from PPA) is that the effects and filters menu does not work. Enabling video adjustments (brightness, contrast etc.) causes black picture. So I had to try others.)

Settings in Linux are stored here:
~/.config/vlc

It turned out that only the parameter "sout-x264-preset=" is unset after a fresh install (and so video conversion looks good because it behaves like "slow"), but after selecting any other video renderer, it sets itself to "ultrafast" (like written on the button).

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differences in vlcrc after switching back and forward: co_windler@Juchhe:~/Dokumente/Arbeit/Config (Juchhe)/vlc$ diff -y --suppress-common-lines vlcrc_Automatisch vlcrc_VDPAU-Ausgabe #sout-x264-preset= | sout-x264-preset=ultrafast #sout-x264-tune= | sout-x264-tune=film #vout= | vout=vdpau_display co_windler@Juchhe:~/Dokumente/Arbeit/Config (Juchhe)/vlc$ diff -y --suppress-common-lines vlcrc_Automatisch vlcrc_wiederAutomatisch #sout-x264-preset= | sout-x264-preset=ultrafast #sout-x264-tune= | sout-x264-tune=film #vout= | vout=any

This bug may seem minor, but this behaviour is extremely confusing to beginners, because the only obvious solution after switching any video output/decoding mode seems to click "Reset Preferences", which will delete ALL user settings (including custom convert mode entries). Thus you must backup at least your vlc-qt-interface.conf (or vlc-qt-interface.ini in Windows) which contains your GUI settings and convert mode. I recommend to also backup vlcrc which seems to store the selected renderer type and all video/audio finetuning.

Please fix this by making the conversion speed button "x264v preset and tuning selection" always reflect the actual setting of parameter "sout-x264-preset=" and set its default to "slow" (or what ever the internal unset behaviour is) instead of "ultrafast", which converts low resolution videos (e.g. 240p at 130kb/s) way too blocky. The bug seems old and exists at least in several VLC 3 versions.

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MAY THE SOFTWARE BE WITH YOU! *============================================================================* I CYBERYOGI Christian Oliver(=CO=) Windler I I (teachmaster of LOGOLOGIE - the first cyberage-religion!) I I ! I *=============================ABANDON=THE=BRUTALITY==========================*

[Rémi Denis-Courmont]

You're not making any sense. x264 is only used for encoding video, not when rendering.

[CO_Windler]

The problem is that the initially uninitialized parameter "sout-x264-preset=" only gets assigned to something ("ultrafast") after first time clicking a (any?) button in the setup menu and so messes up the video conversion mode. This is obviously caused by the way the setup GUI handles button presses (assigning *all* current menu button states to their vlcrc parameters, even when the button only displays a default dummy value that was yet never touched by the user). Sot the "ultrafast" only starts to take effect after clicking other things in the menu.