A hands-on introduction to video technology: image, video, codec and more
It's interesting to note
that the architecture of the first ISO codec MPEG (1)
is almost identical to the one we have today H.265
That codec was standardised in the late 90s
So this design has carried through for about 20 years.
Most of the changes relate to the targeted parameters
such as frame size, frame rate and bitrate.
Only the last step 264 --> 265 seems to have added new features.This is a very well written introduction