[Google Pixel 6 Pro] legend221:
Credits to the developers of the modified GCam project. Please donate to them if possible to keep the development going.

After using it daily on my Pixel 2 XL it is now confirmed working on the Pixel 6.

There are alot of custom options to take that perfect shot available for this modified version, as time passes there will be more releases on the main page on the same site.

Enjoy!

Older version

https://www.celsoazevedo.com/files/android/google-camera/dev-MWP/f/dl23/

Latest version

MWP: Gcam_8.4.300_beta5_MWP

Download Gcam_8.4.300_beta5_MWP by MWP.

www.celsoazevedo.com

Detailed info I found on Google for the app:

What is the lib patcher?

Libpatcher - is a custom setting where you can set all the settings to your liking

Radius Temporal changes the graininess of the image by affecting noise, the higher the image is more blurry and less noise, the lower the more noisy, but more detail

Tone Curve is where you can adjust dark points, white points, shadows, highlights. It is recommended to enable and leave the default values or tweak them (advanced users)

Sharpness allows you to control the sharpness of the image. Zoom in for low-light shots, and zoom out for selfies.

Luminance Noise Reduction is what controls the “graininess” in images caused by high ISO. Decrease it to get more detail at the expense of high noise, or increase it if the noise is unacceptable to you

Color Noise Reduction: Controls color spots. There is usually no need to adjust it as this will not improve the quality, but you can increase it slightly if you see colored spots in the dark. Too much chroma noise can cause a decrease in saturation. Also known as color noise. Be careful with this setting it can mess with the fine details of an image.

Contrast settings allow you to control the contrast of the image. Increase it if you want darker shadows, and decrease it to make it brighter is the general idea. This is again a personal preference

Saturation is what allows you to control the saturation of the image. Increase it if you want more saturated colors in your photos. Obviously decrease if your HDR is getting too saturated. This is again a personal preference

Now there are some advanced settings. These affect the morphological processing. Naturally thats a very basic overview. I took the course while finishing up my engineering degree. It was difficult stuff past the basic level. I wont get into what these settings do beyond a decent generalization.

Warning to all these settings can absolutely have a drastic negative effect on your images. A lot of testing would be necessary by the end user

Luminance noise reduction levels

Level 1 (Detail) changes the photo very slightly, slightly smoothing out small elements in the image.

Level 2 (Rough Surfaces) seriously alters the image by smoothing grain

Level 3 (Edges) doesn’t change much. Smooths edges slightly

Level 4 (Smooth Surfaces) radically alters the image by making it posterized by smoothing out large areas of the same color. Avoid magnification over 1.0

Color noise reduction levels

Level 1 (Detail) fine textures, but the same applies to rough details

Level 2 (Rough surfaces) fine textures, but the same applies to rough details

Level 3 (Edges) Edges are mainly defined by the contrast between one object and another

Level 4 (Smooth Surfaces) Smooth surfaces are generally uniform areas of the image. Like wallpaper with few small details

Tips:

If you notice a certain color of spots on your low light photos. Check its frequency spectrum. Look where its at in the photo and go to the specific wavelet reduction setting and tweak it. See if you can remove it. More often than not these settings are used to improve astrophotography, low light and high detail images.

My sensor has more higher frequency color noise than others. Ive seen some XDA users where they had to turn down denoise. It really all depends on a lot of stuff. Its fun to tweak and squeeze out what you can.

YMMV