YCrCb non-interlaced inputs
to interlaced output
RGB non-interlaced inputs
to interlaced output
RGB non-interlaced inputs
to RGB non- interlaced output
TV NTSC/PAL output support
Interlaced and non-interlaced outputs
d i g i t a l i n f o t a i n m e n t p r o d u c t s
Digital Video Encoder
B t 8 6 8 / 8 6 9
Distinguishing Features
Highest Quality Flicker-Free YCrCb/RGB
to NTSC/PAL Digital Video Encoder with
UltraScaleTM (PC to TV) Technology
Conexant's Bt868 and Bt869 are specifically designed for video
systems requiring the generation of high-quality flicker-free
composite and Y/C (S-video) signals from various YCrCb or
RGB digital streams.
The Bt868/869 digital video encoders provide the industry's
highest TV-out flicker-free output from both interlaced and
non-interlaced (e.g., personal computer) image sources.
Conexant's UltraScale technology provides a fully programmable
DSP engine that allows for the use of the entire viewable area of
a television screen. The device performs 5-line vertical filtering
which includes poly phase interpolation scaling for overscan
compensation and flicker filtering. Using the on-chip PLL and
poly-phase interpolator, the device preserves all the components
of the input signal to create the highest quality display of all
video -- including text-intensive images on NTSC/PAL TVs.
d i g i t a l i n f o t a i n m e n t p r o d u c t s
Digital Video Encoder
B t 8 6 8 / 8 6 9
Video/graphics system
Device Architecture
The Bt868/869 consists of a Color Space Converter/
Flicker Filter engine followed by a video encoder
engine. The Color Space Converter/Flicker Filter
contains a timing generator for requesting and
accepting data from a graphics controller, a color
space converter, and various horizontal video
processing functions -- as well as the flicker filter
and vertical scaler for the overscan compensation.
The output of this engine is fed into a FIFO for
synchronization with the following video
encoder engine.
Flicker Removal and Scaling
Architecture
The Bt868/869 performs 5-line vertical filtering,
which includes poly-phase interpolation scaling
for overscan compensation and flicker filtering.
The Bt868/869 accepts both 640 x 480 and
800 x 600 digital input formats. Conexant's
UltraScale technology converts lines of input
pixel data to appropriate numbers of output lines.
Ultrascale technology provides the most advanced
vertical and horizontal scaling available today,
allowing for the display of non-interlaced data
on interlaced devices such as televisions.
Horizontal scaling for overscan compensation is
achieved by altering the encoder clock frequency.
This approach preserves all of the high-frequency
components of the input signals, which are essential
for display of text-intensive images such as Web
pages on TVs. The Bt868/869 performs no additional
horizontal processing on the input pixels, allowing
the full bandwidth of the input image to be output,
limited only by the 2x upsampling filter response,
which is nominally greater than 6 MHz.
The amount of flicker filtering is programmable. This
process trades off vertical resolution in order to reduce
the flicker, and allows the image to be optimized.
Auto Configuration
The Bt868/869 can configure itself for one of eight combinations
of video formats and input modes with a single register write.
This reduces the software support required, yet allows full
flexibility in generating video formats and timing. Once the
device is configured, all the registers are accessible to modify
the modes. For less common modes, the device can be
configured for the closest mode, and only those registers
that differ need to be programmed.
Pixel Input Formats and Timing
The Bt868/869 converts a wide range of input formats to
television video formats. The input format can be either
non-interlaced in 640 x 480 or 800 x 600 formats, or
interlaced formats such as CCIR 601 format (VMI spec).
What is a Digital Flicker Filter
Video Encoder?
A digital flicker filter video encoder allows PC users to enjoy
the "big screen experience" with their PCs. This means that
instead of being hunched over a small VGA screen when
playing games or watching DVD movies, PC users can now
experience exciting 3D games with the involvement and
full visual impact that only a big screen TV can provide.
The digital flicker filter encoder is a highly sophisticated
chip that converts the high resolution progressive
scan 2D/3D VGA image generated by a PC's graphics
subsystem into a format that can be displayed as an
interlaced TV signal. This conversion process is called
"flicker filtering" because if you were to directly display
a VGA image on a TV set, the image would "flicker"
due to the reduced resolution of the TV set compared
to a VGA monitor. Other flicker filter encoders do
not incorporate digital techniques and rely on analog
technology to do this conversion. This results in fuzzy,
poor quality video.
Only the Conexant digital flicker filter video encoder,
with its crisp video quality, allows the family PC to be
at the center of home entertainment as a game machine
and a home theater. The flicker filter video encoder also
allows the PC's video subsystem to display DVD movies
on the large screen with razor sharp 10-bit video quality.
Functional block diagram
f e a t u r e s a n d s p e c i f i c a t i o n s
YCrCb non-interlaced inputs
to interlaced output
16-bit 4:2:2 multiplexed 8-bit inputs
24-bit 4:4:4 multiplexed 12-bit inputs
24-bit 4:4:4 non-mux 24-bit inputs
RGB non-interlaced inputs
to interlaced output
15/16-bit multiplexed 8-bit inputs
24-bit multiplexed 12-bit inputs
24-bit non-mux 24-bit inputs
RGB non-interlaced inputs to
RGB non-interlaced output
15/16-bit multiplexed 8-bit inputs
24-bit multiplexed 12-bit inputs
24-bit non-mux 24-bit inputs
TV NTSC/PAL output support
in the following modes:
Interlaced and non-interlaced
outputs
Composite
S-video
Simultaneous S-video and
composite YUV output
5-line vertical filtering and
overscan compensation
Support for both 800 x 600
and 640 x 840
Optional Macrovision 7.0
protection supporting
NTSC and PAL
10-bit DACs for superior
picture quality
VMI compatible input
mode for DVD playback
Serial programming interface
8 automatic configuration modes
using a single register write
Master/slave video operation
support using an on-chip PLL
Luma bandwidth of 6 MHz
TV connected register flag
Programmable power-down mode
3.3V operation with 5V tolerant IOs
80-pin PQFP package
Applications
Desktop PCs with TV-out
Portable PCs with TV-out
Living-room PCs
Internet PCs
Internet
TVs
Internet appliances
Master and Slave Modes
The Bt868/869 can operate as either a timing master or a
slave. In master mode, the device will generate and output
HSYNC, VSYNG and BLANK. In slave mode, HSYNC, VSYNG
and BLANK must be provided externally.
It is highly recommended that the device operate as
a master, in order to ensure that the input and output
video stream remain synchronized. By running the
device in master mode, any timing errors that occur
can be absorbed to some extent by the on-board FIFO.
Worldwide Video Standard Support
The Bt868/869 supports worldwide video standards
including NTSC-M (North America, Taiwan, Japan), PAL-B,
D, G, H, I (Europe, Asia), PAL-M (Brazil), PAL-N (Paraguay),
and PAL-Nc (Argentina).
MacrovisionTM Support
The Bt868 and Bt869 are functionally identical, with
the exception that the Bt869 can output the Macrovision
Level 7.01 anticopy algorithm.
www.conexant.com
General Information:
U.S. and Canada: (800) 854-8099
International: (949) 483-6996
Headquarters Newport Beach
4311 Jamboree Rd, P.O. Box C
Newport Beach, CA 92660-3095
Order# 101601A
01-0362
2001, Conexant Systems, Inc. All Rights Reserved.
Conexant and the Conexant logo are trademarks
of Conexant Systems, Inc. Other trademarks are
owned by their respective owners. Although Conexant
strives for accuracy in all its publications, this material
may contain errors or omissions and is subject to
change without notice.
THIS MATERIAL IS PROVIDED AS IS
AND WITHOUT ANY EXPRESS OR IMPLIED WARRANTIES,
INCLUDING MERCHANTABILITY, FITNESS FOR A PARTICULAR
PURPOSE AND NON-INFRINGEMENT.
Conexant shall not be
liable for any special, indirect, incidental or consequential
damages as a result of its use.
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