ZR36057 ZORAN [Zoran Corporation], ZR36057 Datasheet - Page 47

• Manufacturer Part Number: ZR36057
• Description: ENHANCED PCI BUS MULTIMEDIA CONTROLLER
• Manufacturer: ZORAN [Zoran Corporation]

Calculating the Horizontal Parameters:
X and We denote two temporary variables:
HStart and Hend are then calculated from hcrop1 and hcrop2.
In the example:
The ZR36057 will actually sample-in 707 pixels from every line.
The first 6 and the last 7 active pixels will be cut out.
HStart = HStart’ + hcrop1 = 122 + 6 = 128
HEnd = HEnd’ - hcrop2 = 841 - 7 = 834
hcrop1 = 2*floor((720-707)/4) = 6
We = floor (VidWinWid*64/X)
We = floor(597*64/54) = 707
hcrop1 = 2*floor((Wa-We)/4)
X = ceil (VidWinWid*64/Wa)
hcrop2 = Wa - We - hcrop1
X = ceil(597*64/720) = 54
hcrop2 = 720-707 - 6 = 7
HorDcm= 64 - 54 = 10
(834 - 128 + 1 = 707)
HorDcm = 64 - X
hcrop1
VStart’
Total size of one input field
Active portion of one input field
VEnd’
Figure 17. Input Image Parameters
VStart
VEnd
Wa
Enhanced PCI Bus Multimedia Controller
VSYNC
47
The effective portion taken by the ZR36120 according to the
programmed parameters. (The effective portion can be the
entire active field or any partial sub-section of it).
Calculating the Vertical Parameters
(Regardless of DispMod!)
Y and He denote two temporary variables:
VStart and VEnd are then calculated from vcrop1 and vcrop2.
In the example:
The ZR36057 will actually sample-in 235 lines from every field.
The first 2 and the last 3 active lines of every field will be cut out.
floor or ceil (Ht/s)
Ha/2
VStart = VStart’ + vcrop1 = 10 + 2 = 12
VEnd = VEnd’ - vcrop2 = 249 - 3 = 246
vcrop1 = floor(((480/2) - 235) / 2) = 2
vcrop2 = (480/2) - 235 - 2 = 3
Y = ceil (VidWinHt*64*2/Ha)
vcrop1 = floor((Ha/2 - He)/2)
vcrop2 = Ha/2 - He - vcrop1
He = floor(199*64/54) = 235
Y = ceil(199*64*2/480) = 54
He = floor (VidWinHt*64/Y)
VerDcm= 64 - 54 = 10
(246 - 12 + 1 = 235)
VerDcm = 64 - Y
hcrop2