Focus Enhancements FS456 Data Sheet

Page of 41
FS453/4 AND FS455/6 
 
DATA SHEET: HARDWARE REFERENCE 
JANUARY, 2005, VERSION 3.0 
COPYRIGHT 
©2003-4 FOCUS ENHANCEMENTS, INC. 
FOCUS Enhancements Semiconductor  
 
2.4  Patented 2D Flicker Filter 
The Patented 2D Flicker Filter receives video lines from the 2D Scaler and performs vertical filtering to 
reduce or eliminate perceived flicker that is an artifact of the interlaced television format.  
 
The FS453's flicker filter is significantly more effective than a typical three-line-average flicker filter.  The 
FS453’s flicker filter consists of joint horizontal (Sharpness) and vertical (Flicker) controls.  Three-line-
average flicker filters do reduce the visual effect of interlaced image flicker, but they also introduce 
blurring.  The flicker dimension of the FS453's filter reduces image flicker, while the sharpness dimension 
of the FS453's filter reduces image blurring.  Both the sharpness and flicker registers can be programmed 
over a wide range of values to allow the user to customer tailor the filter settings to different display 
devices. 
2.5 FIFO  
The Flicker Filter stores video data in a FIFO memory.  This memory allows the video data to be 
transferred from the graphics clock domain to the TV clock domain.   
2.6  Post (Horizontal Up) Scaler  
The Post Scaler draws information from the FIFO as necessary and scales it horizontally based on the 
up-scale value programmed in the Horizontal Scaling Coefficient (HSC) register.  The scaled data is 
provided at the television clock rate to the SDTV video encoder and the Inverse Color Space.   
2.7  Encoder and Inverse Color Space 
The FS453 contains a broadcast quality, 2X oversampled video encoder with an Inverse Color Space 
matrix.  The encoder combines the chrominance, luminance, and timing information into broadcast quality 
NTSC or PAL composite and YC (S-Video) signals and sends them to the DACs.   
 
The Inverse Color Space transforms YCrCb video data to the RGB color space required for SCART 
output.  If the Inverse Color Space is not used, then the Encoder converts YCrCb to YPrPb as required 
for SDTV YPrPb output.  The RGB or YPrPb signals are sent to the DACs synchronized with the 
Encoder's composite signal.   
 
The FS454 and FS456, which are otherwise identical to the FS453 and FS455, respectively, incorporate 
Macrovision 7 anti-copy protection in the encoder.  The FS454 and FS456 also include 480p protection. 
2.8  Bi and Tri-Level Sync Insertion (HDTV) 
The FS453 also offers HDTV Syncs output modes.  The color matrix, output level, and sync type are fully 
programmable allowing for compatibility with the multiple HDTV standards.  The FS453 inserts bi-level or 
tri-level sync signals as defined by the standards.   
2.9  Configurable 10 bit DACs 
The four output DACs (Digital/Analog Converters) can be configured for several output formats: RGB 
component output (VGA); RGB with CVBS (SCART); CVBS (2 optional) and Y/C (S-Video); and YPrPb 
component output (HDTV or SDTV).  To conserve power the DACs can be run in low power mode or can 
be completely powered down when not in use.   
2.10 Clock Management 
The FS453 synthesizes a 0.78125-150 MHz clock from the 27 MHz XTAL_IN and supplies this clock 
(CLKOUT) to the GCC.  The clock is buffered and returned to the FS453 (CLKIN_P) synchronous to the 
pixel data and sync information.  This clock has a 1.5 Hz resolution and can be adjusted so that the GCC 
scaled input data rate exactly matches the ITU-R BT.656 output data rate. 
2.11  Oscillators and PLL 
The FS453 clock generation circuit operates in one of two modes, NCO (Numerically Controlled 
Oscillator) mode or PLL (Phase Locked Loop) mode.  In NCO mode, the numerically controlled oscillator