PNX1500E NXP Semiconductors, PNX1500E Datasheet - Page 589

• Manufacturer Part Number: PNX1500E
• Manufacturer: NXP Semiconductors

Specifications of PNX1500E

• Lead Free Status / Rohs Status: Not Compliant

NXP Semiconductors
Volume 1 of 1
PNX15XX_PNX952X_SER_N_4
Product data sheet
2.4.4 Vertical Video Filters
2.4.5 De-Interlacing in MBS
2.4.6 Color-Key Processing
The polyphase filter used for vertical processing can only be operated in the normal
polyphase mode.This filter can be used as a two-component 6-tap filter, a three-
component 4-tap filter or a four-component 3-tap filter (optionally, linear phase
interpolation). In the two-component mode, each filter unit can be run independently,
to allow 4:2:0 to 4:2:2 conversion or vice versa.
The current de-interlacing algorithms, implemented inside the MBS, are as follows:
MBS supports both field insertion and line doubling based simple de-interlacing in the
pixel-fetch unit.
If de-interlacing is enabled, the previous and current fields have to be fed into the
scaler as one interleaved frame. For the MSA, the first line has to originate in the
previous field, while in VTM, the first line has to be fetched from the current field.
Base Address Mode = 1 can be selected to assist in weaving the two fields together
into one frame.
Edge Dependent De-Interlacing (EDDI)
The purpose of EDDI is to improve the appearance of long diagonal edges, without
degrading other parts of the image. EDDI is used as a post-processing unit for the de-
interlacer.
Color-key processing, to convert alpha values into color key values and/or vice versa,
are only available for the 4:4:4 video formats.
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Simple Median Filtering (Vertical Temporal Median -- VTM)
Majority Selection Algorithm (MSA)
Field Insertion and Line Doubling
Color Key to Alpha Conversion
To avoid color key values getting altered during video processing, color-key
matching samples can be tagged as transparent by generating an alpha value of
zero at the input of the MBS. Non-keyed samples get assigned a programmable
alpha value. After video processing is over, the alpha value can be stored in
memory together with the other components or can be used to re-key the keying
color back into the video stream (see
Color Key Replace
Scaling of video streams containing color keys can lead to artifacts at the corners
between keyed and non-keyed samples, due to the “smearing effect of the low
pass filter. The effect is heightened by the highly saturated colors normally used
for keying. To avoid these artifacts, color keyed samples are replaced with either
gray, black, or the previous sample (gray if at the start of the line),.
Alpha to Color Key Convert
Rev. 4.0 — 03 December 2007
Alpha to Color Key Convert
Chapter 19: Memory Based Scaler
PNX15xx/952x Series
© NXP B.V. 2007. All rights reserved.
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