6.5 Methods for Restoring Electrical Circuit …
593
Recognized correctly
0
Recognized correctly
30
Recognized correctly
40
Recognized incorrectly
12
Recognized incorrectly
0
Recognized incorrectly
0
Unrecognized
28
Unrecognized
10
Unrecognized
0
a)
b)
c)
Fig. 6.64 Effect of image brightness and contrast on the result of operation of recognition software:
recognition is not possible (a); increased possibility of recognition (b); complete recognition (c)
Fig. 6.65 Shift of characteristic rectangles of a library element: general view of the element (a);
zoomed fragment (b)
the library to reduce the total time required. For this purpose, the general program
includes the command for gathering statistics on the frequency of use of an element.
Figure 6.68 shows the complete route of recovering the circuit of an electrical principal IC based on the set of layered topological images of the chip using the internal
project library and the previously presented recognition and tracing techniques.
This route includes the following stages:
– Recognition of a topology fragment of the working design using an external
library;