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Horizontal
VBI data (0)
hvbi0_hsz
hvbi0_vsz
hvbi0_strt_vps
Horizontal
VBI data (1)
hvbi1_hsz
hvbi1_vsz
hvbi1_strt_vps
hvbi0_strt_vps
vvbi0_hsz
vvbi0_strt_vps
Vertical VBI data (0)
Top field
active video area
vvbi1_hsz
vvbi1_vsz
Vertical VBI data (1)
vvbi1_strt_vps
Bottom field
active video area
vvbi0_strt_vps
Luminance = 10h
Chrominance = 80h
Luminance = 10h
Chrominance = 80h
Bottomfield
v_sync
Field_ID
T
opfield
L1
L2
L3
L4
L5
L6
L7
L8
L9
L10
L11
L12
h_sync
Horizontal blanking
EAV (4words)
hvbi0_strt_hps
hvbi1_strt_hps
vvbi0_strt_hps
SAV (4words)
vvbi1_strt_hps
vvbi0_vsz
Architecture
1772
SPRUH82C – April 2013 – Revised September 2016
Copyright © 2013–2016, Texas Instruments Incorporated
Video Port Interface (VPIF)
35.2.7 VBI Ancillary Data
The VPIF can transmit and receive ancillary data in the video blanking interval (VBI) of BT.656 and
BT.1120 video streams. The ancillary data regions are referred to as:
•
Horizontal Ancillary (HANC) - Data between EAV and SAV (horizontal blanking interval), and
•
Vertical Ancillary (VANC) - Data between SAV and EAV (horizontal active video area).
Transmit and receive of ancillary data is enabled by setting the HANC and VANC bits in the C0CTRL and
C2CTRL control registers.
35.2.7.1 VBI Ancillary Data Transmit
The ancillary data to be transmitted is prepared by the user outside of VPIF. Ancillary register settings
determine the origin position of the ancillary data within the VBI and how much ancillary data is to be
transmitted. Note that the user is expected to place valid ancillary data in a memory buffer that is
representative of the entire VBI region of interest. However, only the valid ancillary data region needs to
be initialized -- the VPIF will automatically transmit blanking data (Y = 10h, C = 80h) for non-valid ancillary
data regions.
As shown in
, the vertical-origin of each data region is offset from the falling edge of the
vertical synchronization signal, and the horizontal-origin of each data region is offset from the SAV and
EAV signals.
The value of the horizontal start position should be a multiple of 8 (HPOS[2:0] = 0) on both the horizontal
and vertical ancillary data regions; the horizontal size can be defined as any value that does not exceed
the data region.
Figure 35-11. VBI Result Data Transmit Image for Interlaced Image