LSI Logic Confidential
11-20
Video Interface
Copyright © 2001, 2002 by LSI Logic Corporation. All rights reserved.
Video Overlay Control Register
Cbus Address: 0xC4000C
Read/write
0x8
NoPx
28
If set when GoRLE is set, the associated sub-picture RLE
window has no pixel control data, that is, the default
colors and alpha values are used for the whole window.
SqPix
27
When GoOSD is set, specifies whether OSD pels in the
associated window are rescaled horizontally by a ratio
specified by the OSD Phase Increment register. If set,
OSD pels are rescaled. If clear, OSD pels are not
rescaled. This bit is set to convert square aspect ratio
pixels to 720H resolution output.
Pre-M
26
If set when GoOSD is set, specifies that software has
pre-multiplied the OSD RGB values in the associated
OSD window by the alpha value. If not set when GoOSD
is set, specifies that OSD RGB values should be
multiplied by alpha before blending with the video layer.
Alpha Mode
[25:24]
When GoOSD is set, specifies the alpha mode of the
associated OSD window, as shown below. The alpha
mode determines how alpha values are determined for
OSD pixels in the window.
31
29
28
27
26
25
24
23
20
19
18
17
16
Reserved
NoPx SqPix Pre-M Alpha Mode
Reserved
Vover
VAcolor
RLEA
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
RLEInt GoRLE
OSD PixFmt
ScaleH
ScaleV
Bott
Top FlickE
0
OSDI OQF GOSD
Alpha Mode Value
Alpha Mode
0
Normal Alpha
1
Inverted Alpha
2
Constant Alpha
3
Transparent Color