This is the driver for a custom EQ effect I made for an AOSP build.
I created a new effect in the libeffect.so in the audioeffects bundle. I altered the EQ effect to allow for more than 5 bands and I inserted a custom DSP in the EQ.

I included the libeffect code in this project. Just copy and paste it into your AOSP project and build it to be able to use this driver.


This app will not work unless you have a 6 band EQ which is not standard for AOSP, you will need to alter your libeffect.so to allow the EQ effect to have 6 bands.


Number of bands lives here:
https://android.googlesource.com/platform/frameworks/av/+/9803acb6b2c1b9c01444e0c8c0124adbe9a7157a/media/libeffects/lvm/lib/Bundle/lib/LVM.h

Number of bands also lives here, and you will need to make the presets support the number of bands you change the numbands to:
https://android.googlesource.com/platform/frameworks/av/+/9803acb6b2c1b9c01444e0c8c0124adbe9a7157a/media/libeffects/lvm/wrapper/Bundle/EffectBundle.h

Also you will need to turn off the gain correction here:
https://android.googlesource.com/platform/frameworks/av/+/9803acb6b2c1b9c01444e0c8c0124adbe9a7157a/media/libeffects/lvm/wrapper/Bundle/EffectBundle.cpp

Lastly, you might need to go into the AudioFlinger and alter the global effects on audio session id 0.