L64105 LSI Logic Corporation, L64105 Datasheet - Page 315

• Manufacturer Part Number: L64105
• Description: Mpeg-2 Audio/video Decoder
• Manufacturer: LSI Logic Corporation

9.9 On-Screen Display
where
A value of zero in the Horizontal Filter Scale register (Register 277,
page
increment value is sampled at the new field boundary to allow the host
to change the scale factor between fields.
Table 9.6
Clearing the Horizontal Filter Enable bit disables the interpolation filter,
leaving the data unfiltered. The filter is automatically disabled during the
auxiliary data area of the display.
The Video Interface integrates a flexible OSD Controller that allows the
overlay of a bitmap image on top of the decoded video or background.
The OSD image may be written to SDRAM by the host (internal mode)
or supplied to the L64105 from an external device (e.g., a character
generator) on the EXT_OSD[3:0] input pins.
The OSD image is not horizontally filtered and is thus always the same
size regardless of the resolution or mode of the video data. In addition,
pan and scan of the video data does not affect the position of the OSD
overlay. The OSD Controller also includes a chroma filter designed to
enhance the edge conditions of OSD areas. This filter can be enabled
by setting the OSD Chroma Filter Enable bit in Register 274
On-Screen Display
Target
720
720
720
720
704
704
704
704
4-64) is equivalent to an increment of 256. The raster mapper
x
means to round the value x to the smallest integer larger than x.
Raster Mapper Increment Value by Source Resolution
Source
352
480
544
640
352
480
544
640
(Source:Target)
Ratio
0.488
0.667
0.755
0.888
0.500
0.682
0.755
0.909
Increment
126
171
194
228
128
175
198
233
Reads/Line
(page
Main
44
60
68
80
44
60
68
80
4-61).
9-23