UG-707
ADV8005 Hardware Reference Manual
For example, if Scale Factor = 1.3
Y, Cb, or Cr Scale Value = 1.3 × 512 = 665.6
Y, Cb, or Cr Scale Value = 666 (rounded to the nearest integer)
Y, Cb, or Cr Scale Value = 1010 0110 10b
Reg 0xE49C, SD scale LSB register = 0x2A
Reg 0xE49D, SD Y scale register = 0xA6
Reg 0xE49E, SD Cb scale register = 0xA6
Reg 0xE49F, SD Cr scale register = 0xA6
Note:
It is recommended that the SD luma scale saturation feature,
, be enabled when scaling the Y output level to avoid excessive
Y output levels.
saturate_luma
, Encoder Map,
Address 0xE487[1]
This bit is used to enable the SD luma scale saturation.
Function
saturate_luma
Description
1
Enabled
0 (default)
Disabled
7.4.12.
SD Hue Adjust Control
When enabled, the SD hue adjust control register is used to adjust the hue on the SD composite and chroma outputs. To enable this feature,
must be programmed to 1.
hue_en
, Encoder Map,
Address 0xE487[2]
This bit is used to enable the hue adjust function.
Function
hue_en
Description
1
Enabled
0 (default)
Disabled
Register 0xE4A0 contains the bits required to vary the hue of the video data, that is, the variance in phase of the subcarrier during active video
with respect to the phase of the subcarrier during the color burst. The
encoder provides a range of ±22.5° in increments of 0.17578125°.
For normal operation (zero adjustment), this register is set to 0x80. Value 0xFF and value 0x00 represent the upper and lower limits, respectively,
of the attainable adjustment in NTSC mode. Value 0xFF and value 0x01 represent the upper and lower limits, respectively, of the attainable
adjustment in PAL mode.
The hue adjust value is calculated using the following equation:
Hue Adjust (°) = 0.17578125° (HCR
d
− 128)
where HCR
d
is the hue adjust control register (decimal).
For example, to adjust the hue by +4°, write 0x97 to
97
x
0
151
128
17578125
.
0
4
=
≈
+
d
where the sum is rounded to the nearest integer.
To adjust the hue by −4°, write 0x69 to
9
6
x
0
105
128
17578125
.
0
4
=
≈
+
−
d
where the sum is rounded to the nearest integer.
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