Chroma
Luma
Progressive
Frame
Top
Field
Bottom
Field
Interpolated
Chroma
+
Chroma
Luma
Progressive
Frame
Top
Field
Bottom
Field
+
Internal Modules
63
SPRUHI7A – December 2012 – Revised June 2016
Copyright © 2012–2016, Texas Instruments Incorporated
High-Definition Video Processing Subsystem (HDVPSS)
In the implementation, we need to interpolate the anchor pixel to get it on-grid. Then, we also need to
interpolate a completely new pixel for YPrPb 4:2:2.
For a progressive input, x = -1/4 for getting the anchor pixel on-grid. x = 1/4 for generating the new pixel.
Lines are scanned from the top of the picture to the bottom.
1.2.1.2.1 For Interlaced YUV420 Input Data
shows how 4:2:0 video is split into top and bottom fields in interlaced format. Chroma is
attached to alternating Luma lines in the top and bottom fields such that color is equally spread out
between the top field and the bottom field. This 4:2:0 interlaced chroma representation is shown in the
following figure.
Figure 1-20. 4:2:0 Interlaced Scan
In each interlaced field, the chroma anchor points are separated by 4 pixel lines, or 8 half pels. The 4:2:2
chroma interpolated color space representation of interlaced pictures is shown in
.
Figure 1-21. Ideal 4:2:2 Chroma Upsampling for Interlaced Scan
Following interpolation, the chroma samples lie on a 4:2:2 grid.