This code enables you to add a fallback featured image for each post author in Genesis child themes only.
The code includes the user I.D for each author.
The fallback image is pulled from the child themes images folder.
The above code uses the genesis_pre_get_image filter however you could also use either the genesis_get_image or genesis_get_image_default_args filters.
The fallback images are only added if a featured image hasn’t been set.
For any posts where you haven’t set an author I.D, a default fallback featured image will be displayed.
This post answers this forum question:
I need to have my default image be different depending on who the author is.