Fusion 878A
2.0 Functional Description
PCI Video Decoder
2.8 Coring
100600B
Conexant
2-23
2.8 Coring
The Fusion 878A video decoder can perform a coring function, in which it forces
all values below a programmed level to be 0. This is useful as the human eye is
more sensitive to variations in black images. By taking near-black images and
turning them into black, the image appears clearer to the eye.
Four coring values can be selected: 0, 8, 16, or 32 above black. If the total
luminance level is below the selected limit, the luminance signal is truncated to
the black value. If the luma range is limited (i.e., black is 16), then the coring
circuitry automatically takes this into account and references the appropriate
value for black. Coring is illustrated in
Figure 2-14. Coring Map
32
16
8
0
32
16
8
0
Calculated
Luma Value
Output
Luma Value
879A_019