N64 Audio volumne (SDL vs OMX)

maz

RPi 3
4.1 from SD Card
Currently debugging with keyboad

I have a portable system with mini speakers. It is important I can change the sound volume depending on where I am. From reading wiki and other posts, the default mupen64plus config uses the omx audio plugin, which is extra loud and has no volume control. Supposedly you can use the SDL audio plugin, which allows for volume control or will at least listen to the master volume control. I update the UI-Console section for the Audio Plugin to be SDL specifically AudioPlugin = "mupen64plus-audio-sdl.so" it gets overwritten back to omx after I first load a rom. I checked the mupen files and the audio-sdl.so is there. I have successfully update the config file with other changes that work. So I know I am writing the file properly.

LR-Glupen works properly as it uses retroarch, but I have certain games that are only playable on mupen

BuZz

@maz ~~by default it should sdl audio now - try removing all the configs and re-installing.~~

BuZz

Actually it's probably the auto config default from an old install you have - make sure in /opt/retropie/configs/all/autoconf.cfg you have mupen64plus_audio = "0"

This is actually documented here - https://github.com/retropie/retropie-setup/wiki/Nintendo-64#mupen64plus

BuZz

Checked source history - we used to set SDL as default, but it was set back to omx again - I guess for a good reason (not my change and I'm less familiar with some of the reasons for mupen64 changes). But you can control it from the config above.

[edit] It was for performance reasons -Use audio-omx as default audio plugin. Games run much faster if audio-omx is used.

maz

Thanks, sorry about missing that. I didn't realize that is what that line actual meant. I will remember to look more at in the future.

Thanks for finding and checking the committ comment for me as well. I figured there had to be a good reason. I will watch and compare performance to see what works best for me.

I am guessing no way to change volume for omx, it just is what it is?

BuZz

@maz not without sourcecode changes at least.

maz

Let me know if this is way to low a priority or if I should put it in Ideas section.

I was looking over the code for [OMX](lhttps://github.com/ricrpi/mupen64plus-audio-omx/blob/master/src/main.c the commit volum section is commented out, saying it doesn't work with Raspberry Pi. I was poking around and it looks like the omx player for raspberry pi which uses OMX as well does support volume control. That code looks to be in C++ instead of C, but has similarities in terms of populating the struct and setting it omxErr = OMX_SetConfig(OMX_Handle, OMX_IndexConfigAudioVolume, &volumeConfig);

That line is from omxplayer
line 812

Any chance OMX was update for RPi and this plugin wasn't aware? My C/C++ skills are out of date especially with linux, so I would not know how to properly get all the source needed to build, make the change. Sadly I have used too much Visual Studio and Windows development. Code would have to be commented out, and also added to call the commented code to increase / decrease.