bt848kpf ETC-unknow, bt848kpf Datasheet - Page 114

• Manufacturer Part Number: bt848kpf
• Description: Single-chip Video Capture For Pci
• Manufacturer: ETC-unknow

C
Vertical Scaling Register, Upper Byte
Vertical Scaling Register, Upper Byte
Memory Mapped Location 0x04C – Even Field (E_VSCALE_HI)
Memory Mapped Location 0x0CC – Odd Field (O_VSCALE_HI)
Upon reset it is initialized to 0x60.
Vertical Scaling Register, Lower Byte
Memory Mapped Location 0x050 – Even Field (E_VSCALE_LO)
Memory Mapped Location 0x0D0 – Odd Field (O_VSCALE_LO)
Upon reset it is initialized to 0x00.
104
Bits
Bits
ONTROL
[4:0]
[7:0]
[7]
[6]
[5]
R
EGISTER
Type
Type
RW
RW
RW
RW
RW
D
Default
0
1
1
00000
Default
0x00
EFINITIONS
Name
YCOMB
COMB
INT
VSCALE_HI
Name
VSCALE_LO
Description
Luma Comb Enable: When enabled, the luma comb filter performs
a weighted average on 2, 3, 4, or 5 lines of luminance data. The
coefficients used for the average are fixed and no interpolation is
performed. When disabled by a logical zero, filtering and full verti-
cal interpolation is performed based upon the value programmed
into the VSCALE register.
Chroma Comb Enable: This bit determines if the chroma comb is
included in the data path. If enabled, a full line store is used to
average adjacent lines of color information, reducing cross-color
artifacts.
Interlace: This bit is programmed to indicate if the incoming video
is interlaced or non-interlaced. For example, if using the full frame
as input for vertical scaling, this bit should be programmed high. If
using a single field for vertical scaling, this bit should be pro-
grammed low.
Vertical Scaling Ratio: These five bits represent the most signifi-
cant portion of the 13-bit vertical scaling ratio register.
Description
Vertical Scaling Ratio: These eight bits represent the least signifi-
cant byte of the 13-bit vertical scaling ratio register. They are con-
catenated with five bits in VSCALE_HI. The following equation
should be used to determine the value for this register:
VSCALE = ( 0x10000 – { [ ( scaling_ratio ) – 1] * 512 } ) & 0x1FFF
0*
1
0
1*
0
1*
L848A_A
= Vertical low-pass filtering and vertical interpolation
= Vertical low-pass filtering only
= Chroma comb disabled
= Chroma comb enabled
= Non-interlace VS
= Interlace VS
Single-Chip Video Capture for PCI
Bt848/848A/849A
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