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These memories constitute the look-up table for the converting 
into false colour the 16 levels of grey. 
The output of the RAM is converted in analogic form by the 
blocks 9, 10, 11 giving the levels of the three basic colours: RED, 
GREEN, BLU. 
Block 12 has the function of making these signals compatible 
with the TV colour set operating characteristics. 
With this system it is possible to change the false colour 
coding, by changing, with an appropriate program, the content of 
the RAM. 
System in fig. 2 
In this system the functions of the blocks 1 to 5 are the same 
as the ones described in the previous system. 
Here the RAM's are used as support functions for the false 
colour coding. 
The RAM output data (previously addressed by the ADC output) 
are now decoded by the 9, 10, 11 blocks which, in turn, address a 
single switch for each input combination. 
This operation enables the transfer of the SCM (level of grey) 
luminance signal properly weighed. The weights are constituted by 
high precision resistive dividers. The design and values of these 
dividers fix the resolution capability of the image representation 
in false colour, together with the scale of distribution of its 
tonality. 
The switch output are de-multiplexed by using three operational 
circuits, hence they are combined by the colour encoder, whose 
output is the video signal which drives the TV display screen. 
12° July 1978