2/24/2008 9T6WP
BCM7405
Preliminary Hardware Data Module
Functional Description
06/29/07
Bro a d c o m C o rp o r a ti o n
Page 1-50
Video and Graphics Display
Document
7405-1HDM00-R
D
IGITAL
V
IDEO
D
ECODER
(ITU-R-656)
The BCM7405 contains an ITU-R-656 digital video decoder. The decoder supports the modes outlined in
. For all
formats, the incoming data is 4:2:2 format with two luminance samples combined with one chrominance sample for each of
the red and blue color spaces.
VBI Decoding
A
NALOG
V
IDEO
E
NCODER
The BCM7405 employs a analog video encoder (VEC) with Macrovision 7.1 support capable of processing one high
definition video stream and one standard definition (that is scaled down content from the high definition video stream).
Instead of replicating identical modules, the VEC is built out of distinct block elements to meet the preferred customer
requirements. Therefore, the VEC is a single module that takes a series of video inputs from multiple sources, inserts fly
backs (hblank and vblank), formats the signal into multiple valid output video standards, and additionally handles the
insertion of non-video signals into the VBI region. The VEC supports a variety of analog video standards (NTSC, NTSC-J,
PAL (all variations including PAL-M/Nc), SECAM, as well as a variety of output formats: composite, S-Video, SCART1,
SCART2, component (480i, 480p, 576i, 576p, 720p, 1080i, 1080p24, and 1080p30). The VEC uses a fixed clock
architecture.
Table 1-6: Digital Video Decoder Supported Modes
Clock (MHz)
Standard
Resolution
Notes
27
ITU-R-656
525i, 625i
SD resolution; 525i and 625i
27
###
240p
4:2:2 digital format
Table 1-7: VBI Decoding
VBI Input Source
Standard
Mnemonic
Direct Decode
Sample and
Store to Memory
Ancillary Data
Packets
Analog Video (525i
NTSC) composite
input only
IEC 61880-1
BVID
Yes
Yes
–
EIA-608
Closed Caption
Yes
Yes
–
ETS 300 294
WSS
Yes
Yes
–
–
NABTS
Yes
Yes
–
Analog Video (625i
PAL) composite input
only
IEC 61880-1
BVID
Yes
Yes
–
EIA-608
Closed Caption
Yes
Yes
–
ETS 300 294
WSS
Yes
Yes
–
–
Teletext
Yes
Yes
–