SDA9410
Preliminary Data Sheet
Input signal processing
TH_AA
TH_LB
SLAA
TH_DN_BN
YINM
Processing
Start/End-
line
Status_SLAA
ELAA
Line
Type
Decision
Histogram
Decision
Status_ELAA
RELY
LT
Reliability
Evaluation
TH_MUNSL, TH_AUNS
TH_ALB, TH_MA_AA
Figure 20
Block diagram of letter box detection
Each line of the input picture will be assigned to one of three line types (LT) by the
“Histogram” and “Line Type decision” block. The figure below shows in detail the
functionality of both blocks. The “Histogram” block counts the amount of pixels (BC),
which are larger or equal 2*TH_DN_BN (I²C Bus parameter, 1Ch). Depending on the
counter value the line is assigned to one of the three line types by the “Line Type
Decision” block. The I²C parameter TH_AA and TH_LB can be used to influence the
result of the “Line Type Decision” block.
Line Type (LT)
Priority
BC
AA
1
2
3
>= 4 * TH_AA
LB
< 4 * TH_LB
UNS
< 4 * TH_AA and >= 4 * TH_LB
Table 28
Line Type Decision of LBD
The line type AA marks lines which belong to an active area, the line type LB marks lines
which belong to a letter box area (maybe including logos, subtitles) and the line type UNS
marks lines which could not assigned with security to one of both line types mentioned
before.
47
Micronas
MICRONAS [ MICRONAS ]
