Speed up renders by disgarding transparent areas / averaging similar tiles

Why is Blender wasting time rendering transparent areas when “film transparent” is activated ?

Is it possible to cancel rendering tiles on transparent areas and move to the next one until it meets an object to render ?
Renders could speed up by 200-300 %

Also, is there an algorithm that could average a tile between similar pixels so that on flat colours or similar areas, the tile renders speed up making an average between 2 pixels to create the 3rd one ? (pixel or tile)

I remember that modo faced this problem many years ago and found a solution through what i just explained above.
Hope tit would help.

This has already been discussed many times, you search on Google about why this happens with Cycles.
Anyway, if we are lucky, soon we could have adaptive sampling in Cycles with which that problem would be minimized a lot.


Indeed, that was adaptive sampling. The result was very good and much faster.
Well, cross finger then.
Thanks for your feed back