Rudy Michau writes:
I share with you how you can improve the classic way to made blurred image in Cycles for Blender. This node make more real blur for your image with shades and not only distortion.
Thank you to Secrop for ShaderNodeExtraShader which greatly facilitates the creation of custom nodes.
Thanks you to Sirmaxim for helped me with coding. Thanks you to BlenderArtists.orgwhich allowing these exchanges!