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Running
Average
Downscaler
Polyphase
Scaler
YCbCr
422
YCbCr
422
use_rav
1
0.9
0.8
0.7
0.6
0.5
0.4
0.3
0.2
0.1
0
0
0.05 0.01
0.15
0.2
0.25
f/fs
0.3
0.35
0.4
0.45
0.5
mag
5 Tap Peaking Filter [-x 0 2x 0 -x]
x=0
x=1/16
x=2/16
x=3/16
x=4/16
Internal Modules
194
SPRUHI7A – December 2012 – Revised June 2016
Copyright © 2012–2016, Texas Instruments Incorporated
High-Definition Video Processing Subsystem (HDVPSS)
Parameters for the Peaking filters are defined in CFG_SC19-22. The frequency responses of the peaking-
filter with different sets of coefficients are shown in
. If the source of the input video is NTSC
or PAL format, the peaking filter can be configured to reject the color subcarrier frequency.
Figure 1-143. Peaking Filter at fs/4
1.2.11.2.3 Vertical Scaler
The vertical scaler has a poly-phase and a running average filter as shown in
. While the
poly-phase filter can be used for any up-scaling and preferably downscaling to 3/16 scale factor, the
running average filter is used only for downscaling to a ½ or less size. Selection between these two
scalers is based on the user setting of “use_rav” parameter, according to the user preference of the
tradeoff between sharpness preserving and introduced artifacts.
Figure 1-144. Vertical Scaler Block Diagram