ADV7191 Analog Devices, ADV7191 Datasheet - Page 40

• Manufacturer Part Number: ADV7191
• Description: Video Encoder with Six 10-Bit DACs and Video Encoder with Six DAC Outputs
• Manufacturer: Analog Devices

ADV7190/ADV7191
Sharpness CONTROL REGISTER (PR)
(Address (SR5–SR0) = 22H)
The sharpness response register is an 8-bit-wide register. The
four MSBs are set to 0. The four LSBs are written to in order to
select a desired filter response. Figure 76 shows the operation
under control of this register.
PR BIT DESCRIPTION
Sharpness Response Value (PR3–PR0)
These four bits are used to select the desired luma filter response.
The option of twelve responses is given supporting a gain boost/
attenuation in the range –4 dB to +4 dB. The value 12 (1100)
written to these four bits corresponds to a boost of +4 dB while
the value 0 (0000) corresponds to –4 dB. For normal operation
these four bits are set to 6 (0110).
Note: Luma Filter Select has to be set to Extended Mode and
Sharpness Filter Enable Control has to be enabled for settings
in the Sharpness Control Register to take effect (MR02–04 =
100; MR74 = 1). See Internal Filter Response section.
Reserved (PR4–PR7)
A Logic 0 must be written to these bits.
DNR REGISTERS 2–0
(DNR 2–DNR 0)
(Address (SR5–SR0) = 23H–25H)
The Digital Noise Reduction Registers are three 8-bit wide
register. They are used to control the DNR processing. See
Digital Noise Reduction section.
Coring Gain Border (DNR00–DNR03)
These four bits are assigned to the gain factor applied to border
areas.
In DNR Mode the range of gain values is 0–1, in increments of
1/8. This factor is applied to the DNR filter output which lies
below the set threshold range. The result is then subtracted
from the original signal.
In DNR Sharpness Mode the range of gain values is 0–0.5, in
increments of 1/16. This factor is applied to the DNR filter out-
put which lies above the threshold range.
The result is added to the original signal.
Coring Gain Data (DNR04–DNR07)
These four bits are assigned to the gain factor applied to the luma
data inside the MPEG pixel block.
In DNR Mode the range of gain values is 0–1, in increments of
1/8. This factor is applied to the DNR filter output which lies
below the set threshold range. The result is then subtracted
from the original signal.
In DNR Sharpness Mode the range of gain values is 0–0.5, in
increments of 1/16. This factor is applied to the DNR filter out-
put which lies above the threshold range. The result is added to
the original signal.
PR7
ZERO MUST BE
PR6
WRITTEN TO
THESE BITS
PR7 – PR4
PR5
PR4
PR3
RESPONSE VALUE
PR2
SHARPNESS
PR3 – PR0
PR1
PR0
Figures 77 and 78 show the various operations under the control
of DNR Register 0.
DNR1 BIT DESCRIPTION
DNR Threshold (DNR10–DNR15)
These six bits are used to define the threshold value in the range
of 0 to 63. The range is an absolute value.
Border Area (DNR16)
In setting DNR16 to a Logic 1 the block transition area can be
defined to consist of four pixels. If this bit is set to a Logic 0 the
border transition area consists of two pixels, where one pixel
refers to two clock cycles at 27 MHz.
Block Size Control (DNR17)
This bit is used to select the size of the data blocks to be processed
(see Figure 79). Setting the block size control function to a
Logic 1 defines a 16 × 16 pixel data block, a Logic 0 defines an
8 × 8 pixel data block, where one pixel refers to two clock cycles
at 27 MHz.
DNR07
DNR07
DNR DNR DNR DNR
DNR DNR DNR DNR
07
07
0
0
0
0
0
0
0
0
1
0
0
0
0
0
0
0
0
1
CORING GAIN DATA
CORING GAIN DATA
DNR06
DNR06
06
06
0
0
0
0
1
1
1
1
0
0
0
0
0
1
1
1
1
0
720
05
05
0
0
1
1
0
0
1
1
0
0
0
1
1
0
0
1
1
0
(NTSC)
485 PIXELS
DNR05
DNR05
04
04
0
1
0
1
0
1
0
1
0
0
1
0
1
0
1
0
1
0
0
1/16
2/16
3/16
4/16
5/16
6/16
7/16
8/16
0
1/8
2/8
3/8
4/8
5/8
6/8
7/8
1
DNR04
DNR04
PIXEL BLOCK
DNR03
DNR03
8
DNR DNR DNR DNR
DNR DNR DNR DNR
03
03
0
0
0
0
0
0
0
0
1
8
0
0
0
0
0
0
0
0
1
CORING GAIN BORDER
CORING GAIN BORDER
BORDER DATA
2 PIXEL
DNR02
DNR02
02
02
0
0
0
0
1
1
1
1
0
0
0
0
0
1
1
1
1
0
PIXEL BLOCK
01
01
0
0
1
1
0
0
1
1
0
0
0
1
1
0
0
1
1
0
8
DNR01
DNR01
8
00
00
0
1
0
1
0
1
0
1
0
0
1
0
1
0
1
0
1
0
0
1/16
2/16
3/16
4/16
5/16
6/16
7/16
8/16
0
1/8
2/8
3/8
4/8
5/8
6/8
7/8
1
DNR00
DNR00