SAA4956TJ NXP Semiconductors, SAA4956TJ Datasheet - Page 13

• Manufacturer Part Number: SAA4956TJ
• Manufacturer: NXP Semiconductors

Specifications of SAA4956TJ

• Operating Temperature (max): 70C
• Operating Temperature (min): 0C
• Mounting: Surface Mount
• Operating Temperature Classification: Commercial
• Lead Free Status / RoHS Status: Supplier Unconfirmed

Philips Semiconductors
The start position, when the first phase of the 4 : 1 : 1 YUV
data word is expected on the input bus, is defined by the
first valid written or read word after a reset write or a reset
read operation. The luminance input signal is expected in
8-bit straight binary format, whereas U and V input signals
are expected in twos complement format. U and V input
signals are inverted if the corresponding I
chroma_invert is set to logic 1.
7.2.2
After reformatting, the frequencies of the difference signals
of luminance (delta Y) and chrominance (delta U/V) can
be divided optionally in an upper band (HF) and lower
band (LF) with a lowpass-filter in both signal paths.
The lower frequency band signals (LF delta Y and
LF delta U/V) will be used as input for the noise reduction
function. The lower frequency band on these signals
means that the specific picture contents does not move or
is moving slowly. Optionally, it is possible to bridge the
band-splitting (I
7.2.3
The same signals, on which the noise reduction will be
applied, are used to detect the amount of motion in the
difference signals. Therefore, the absolute value of the
difference signals are generated and limited to a maximum
value. Afterwards the absolute values of the difference
signal of U and V are averaged. The signals are low-pass
filtered to smooth these signals. The filtered signals are
amplified, depending on the setting of the I
Yadapt_gain respectively Cadapt_gain (see Table 2).
Table 2 Gain settings of adaptive values for
1998 Dec 08
Yadapt_gain/Cadapt_gain[2 to 0]
2.9-Mbit field memory with noise reduction
HEX
00
01
02
03
04
05
06
07
B
M
chrominance and luminance
AND
OTION DETECTION
-
SPLITTING
2
C-bus control: unfiltered = 1).
DECIMAL
00
01
02
03
04
05
06
07
2
C-bus control bit
2
C-bus controls:
GAIN
128
16
32
64
1
2
4
8
8
8
8
8
8
8
8
8
13
The amplified signals, which correlate to the amount of
movement in the chrominance respectively luminance
signal path, are transferred into 1 out of 16 possible
K-factor values via look-up tables. The K-factor values are
defined by step values of the look-up tables. The step
values are programmed via the I
Kstep0 to Kstep7 (see Table 3). These values are valid for
the look-up tables of the chrominance and the luminance.
For example, Kstep3 = 4 means: values which are smaller
than 8 (4 times weight of 2) are at least K =
and values equal or higher than 8 are at least K =
higher.
7.2.4
The amount of noise reduction (field averaging) is
described via the K-factor. K = 1 means that no averaging
is applied and the new field information is used. K = 0
means that no averaging is applied and thus only the old
field information is used like a still picture mode. All values
in between mean that a weighted averaging is applied. It is
possible to use fixed K-factor values if the I
lumafix respectively chromafix is set to logic 1.
The possible fixed K-factor values of the I
variables Klumafix and Kchromafix are described in
Table 3.
Table 3 Settings of fixed K-factor values
Klumafix/Kchromafix[3 to 0]
HEX
0A
0B
0C
0D
0E
00
01
02
03
04
05
06
07
08
09
0F
K-
FACTOR
DECIMAL
00
01
02
03
04
05
06
07
08
09
10
12
13
14
15
11
2
Preliminary specification
C-bus-controls:
SAA4956TJ
2
2
C-bus control
C-bus variable
K-factor
3
8
10
11
12
13
14
16
1
2
3
4
5
6
7
8
9
or smaller
0
16
16
16
16
16
16
16
16
16
16
16
16
16
16
16
4
8
or