TMC22191 CADEKA [Cadeka Microcircuits LLC.], TMC22191 Datasheet - Page 42

• Manufacturer Part Number: TMC22191
• Description: Digital Video Encoders/Layering Engine
• Manufacturer: CADEKA [Cadeka Microcircuits LLC.]

TMC22091/TMC22191
2-Layer Keying with the TMC22091
The TMC22091 facilitates the keying of PD port input data
over the CVBS bus input data. Keying is controlled on a
pixel-by-pixel basis by either the KEY input pin or the inter-
nal Data Key. The first two layers in the previous 4-Layer
Example apply to the TMC22091. The result of keying is an
effect where a MIDGROUND source image (i.e. Happy Face
from PD data) is superimposed over a BACKGROUND
source image (i.e. variable matte color from CVBS data).
Table 14. Layer Assignments, Image Sources, and Keying Controls (TMC22191)
Notes:
1. For LAYMODE = 0 to 7, Pixel Data always passes through the CLUTs. FORMAT, INMODE, and the BYPASS pin selects the
2. For LAYMODE = 8 to F and BYPASS = HIGH, Data Key is disabled.
3. Asserting the signal listed under "Keying Control:" enables the corresponding "Signal Source:". Signals with " " are asserted
42
LAYMODE
LCR 04
input format for PD
by a logic LOW.
C
D
A
B
E
F
0
1
2
3
4
5
6
7
8
9
PD(YC
PD(YC
PD(YC
PD(YC
PD(YC
PD(YC
PD(YC
Image Source
Background
PD(RGB)
PD(RGB)
PD(RGB)
PD(RGB)
PD(RGB)
B
B
B
B
B
B
CVBS
CVBS
CVBS
CVBS
C
C
C
C
C
C
R
R
R
R
R
R
B
23-0
, RGB, CI)
, RGB, CI)
, RGB, CI)
, RGB, CI)
, RGB, CI)
, RGB, CI)
C
R
, CI)
according to Table 6.
PD(YC
PD(YC
PD(YC
Image Source
OVERLAY
OVERLAY
OVERLAY
PD(RGB)
B
CVBS
CVBS
CVBS
CVBS
CVBS
CVBS
CVBS
CVBS
CVBS
C
R
B
B
C
C
Midground
, RGB, CI)
R
R
, CI)
, CI)
Data Key
Data Key
Data Key
Data Key
BYPASS
Data Key
Data Key
BYPASS
Control
Keying
KEY or
KEY or
KEY or
KEY or
KEY or
KEY or
OL
OL
OL
KEY
KEY
KEY
KEY
KEY
4-0
4-0
4-0
PD(YC
PD(YC
PD(YC
Assigning Video Sources to Layers with the
TMC22191
Digital video inputs to the TMC22191 (PD, CVBS, Overlay)
are assigned to the four layers by choosing one of the 16
modes of the Layering Control Register. OVERLAY is
always keyed (switched on a pixel-by-pixel basis from active
to transparent) by the OL
programmed to the BACKGROUND layer. The CVBS digi-
tal video bus can be assigned to any of the four layers and is
keyed by the KEY input signal or internal Data Key. In
modes 0 thru 7, the CLUTs are not bypassed and the
BYPASS input is ignored.
Image Source:
PD(YC
PD(YC
OVERLAY
OVERLAY
OVERLAY
OVERLAY
OVERLAY
OVERLAY
PD(RGB)
B
B
B
CVBS
CVBS
C
C
C
—
R
R
R
B
B
Foreground
, RGB, CI) Data Key
, RGB, CI) Data Key
, RGB, CI)
C
C
R
R
, CI)
, CI)
Data Key
Data Key
BYPASS
BYPASS
Data Key
Control
Keying
KEY or
KEY or
KEY or
OL
OL
OL
OL
OL
OL
KEY
—
—
4-0
4-0
4-0
4-0
4-0
4-0
4-0
inputs. OVERLAY can not be
PD(YC
PD(YC
PD(YC
PD(YC
PD(YC
Image Source:
PRODUCT SPECIFICATION
OVERLAY
OVERLAY
OVERLAY
OVERLAY
OVERLAY
B
B
Downstream Key
CVBS
C
C
—
—
—
—
—
R
R
B
B
B
, RGB, CI) Data Key
, RGB, CI) Data Key
C
C
C
R
R
R
, CI)
, CI)
, CI)
Data Key
BYPASS
BYPASS
BYPASS
Control
Keying
KEY or
OL
OL
OL
OL
OL
—
—
—
—
—
4-0
4-0
4-0
4-0
4-0