bt829bkrf ETC-unknow, bt829bkrf Datasheet - Page 43

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

Bt829B/827B
VideoStream II Decoders
1.8.1 The Hue Adjust Register (HUE)
1.8.2 The Contrast Adjust Register (CONTRAST)
1.8.3 The Saturation Adjust Registers (SAT_U, SAT_V)
1.8.4 The Brightness Register (BRIGHT)
1.8 Video Adjustments
The Bt829B provides programmable hue, contrast, saturation, and brightness.
The Hue Adjust Register is used to offset the hue of the decoded signal. In NTSC,
the hue of the video signal is defined as the phase of the subcarrier with reference
to the burst. The value programmed in this register is added or subtracted from the
phase of the subcarrier, which effectively changes the hue of the video. The hue
can be shifted by 90 degrees. Because of the nature of PAL/SECAM encoding,
hue adjustments cannot be made when decoding PAL/SECAM.
The Contrast Adjust Register (also called the luma gain) provides the ability to
change the contrast from approximately 0 percent to 200 percent of the original
value. The decoded luma value is multiplied by the 9-bit coefficient loaded into
this register.
The Saturation Adjust Registers are additional color adjustment registers. It is a
multiplicative gain of the U and V signals. The value programmed in these regis-
ters are the coefficients for the multiplication. The saturation range is from
approximately 0 percent to 200 percent of the original value.
The Brightness Register is simply an offset for the decoded luma value. The pro-
grammed value is added or subtracted from the original luma value which
changes the brightness of the video output. The luma output is in the range of 0 to
255. Brightness adjustment can be made over a range of –128 to +127.
D829BDSA
1.0 Functional Description
1.8 Video Adjustments
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