SAA7118E/V1/M5,557 Trident Microsystems, Inc., SAA7118E/V1/M5,557 Datasheet - Page 57

• Manufacturer Part Number: SAA7118E/V1/M5,557
• Manufacturer: Trident Microsystems, Inc.

Specifications of SAA7118E/V1/M5,557

• Adc/dac Resolution: 9b
• Screening Level: Commercial
• Package Type: LBGA
• Pin Count: 156
• Lead Free Status / RoHS Status: Supplier Unconfirmed

NXP Semiconductors
SAA7118_7
Product data sheet
8.4.3.2 Vertical scaler (subaddresses B0h to BFh and E0h to EFh)
Vertical scaling of any ratio from 64 (theoretical zoom) to
The vertical scaling block consists of another line delay, and the vertical filter structure,
that can operate in two different modes; Linear Phase Interpolation (LPI) and
accumulation (ACM) mode. These are controlled by YMODE[B4h[0]]:
The phase and scale controlling DTO calculates in 16-bit resolution, controlled by
parameters YSCY[15:0] B1h[7:0] B0h[7:0] and YSCC[15:0] B3h[7:0] B2h[7:0],
continuously over the entire field. A start offset can be applied to the phase processing by
means of the parameters YPY3[7:0] to YPY0[7:0] in BFh[7:0] to BCh[7:0] and YPC3[7:0]
to YPC0[7:0] in BBh[7:0] to B8h[7:0]. The start phase covers the range of
lines offset.
By programming appropriate, opposite, vertical start phase values (subaddresses
B8h to BFh and E8h to EFh) depending on odd or even field ID of the source video stream
and A or B page cycle, frame ID conversion and field rate conversion are supported (i.e.
de-interlacing, re-interlacing).
Figure 39
Remark: The vertical start phase, as well as scaling ratio are defined independently
for the luminance and chrominance channel, but must be set to the same values in
the actual implementation for accurate 4 : 2 : 2 output processing.
The vertical processing communicates on its input side with the line FIFO buffer. The
scale related equations are:
•
•
•
•
LPI mode: In LPI mode (YMODE = 0) two neighboring lines of the source video
stream are added together, but weighted by factors corresponding to the vertical
position (phase) of the target output line relative to the source lines. This linear
interpolation has a 6-bit phase resolution, which equals 64 intra line phases. It
interpolates between two consecutive input lines only. LPI mode should be applied for
scaling ratios around 1 (down to
ACM mode: The vertical Accumulation (ACM) mode (YMODE = 1) represents a
vertical averaging window over multiple lines, sliding over the field. This mode also
generates phase correct output lines. The averaging window length corresponds to
the scaling ratio, resulting in an adaptive vertical low-pass effect, to greatly reduce
aliasing artefacts. ACM can be applied for downscales only from ratio 1 down to
ACM results in a scale dependent DC gain amplification, which has to be
precorrected by the BCS control of the scaler part.
Scaling increment calculation for ACM and LPI mode, downscale and zoom:
YSCY[15:0] and YSCC[15:0] = lower integer of
BCS value to compensate DC gain in ACM mode (contrast and saturation have to be
set): CONT[7:0] A5h[7:0] respectively SATN[7:0] A6h[7:0] =
lower integer of
and
Figure 40
Nline_out
---------------------- -
Nline_in
Rev. 07 — 7 July 2008
and
Table 13
Multistandard video decoder with adaptive comb filter
64
, or = lower integer of
1
2
and
), it must be applied for vertical zooming.
Table 14
describe the use of the offsets.
1024
1
63
---------------------------- -
YSCY[15:0]
---------------------- -
Nline_out
Nline_in
(icon) can be applied.
1024
SAA7118
© NXP B.V. 2008. All rights reserved.
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