Add new image format in blender 2.9x

Hello. How to properly write a new image format into a blender?
I found the code in the source code where the formats are spelled out, for example bmp. I registered everything by analogy with bmp in 3 files and it does not even show the files when choosing my conductor.
Where and what else should I prescribe?
In 3ds max, I was already collecting a new format from bmp, but there it is not necessary to collect the entire max.
bf_imbuf this is all spelled out.

I made the same file but named it rsb and inside everything I renamed as rsb.
IMB_filetype.h here I registered my RSB.
filetype.c here I registered my RSB
IMB_imbuf_types.h here I registered my RSB
Where else do you need to register for the files to be displayed?
bmp.c this is how I took the bmp format reading itself.

Everything seems to be how it turned out to be registered in the blender structure. The format has been added.
I really don’t know how to add a reading of the texture itself.
Who can help make reading format for blender?
I have a description of the format structure.