bt829bkrf ETC-unknow, bt829bkrf Datasheet - Page 54

• Manufacturer Part Number: bt829bkrf
• Description: Video Streamii Decoders
• Manufacturer: ETC-unknow

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1.0 Functional Description
1.10 Closed Captioning and Extended Data Services Decoding
1.10.3 Coring
The Bt829B video decoder can perform a coring function, in which it forces all
values below a programmed level to be zero. This is useful because 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.
0x12): 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. This is illustrated
in Figure 1-26.
Figure 1-26. Coring Map
Four coring values can be selected by the Output Format Register (OFORM;
D829BDSA
32
16
8
0
0
8
Luma Value
Calculated
16
32
VideoStream II Decoders
Bt829B/827B