Vivitek RP56HD21, Руководство по обслуживанию

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RGB input from the VGA connector
From the VGA input, a differential RGB signal goes to the input ADC (MST 9883). This chip looks at
the vertical, horizontal. From there, the signal is converted to a 24 bit digital signal and sent to Scaler chip via the
digital bus.
The VGA connector also accepts differential inputs for direct processing. A software lookup table is used to
determine what type of signal is present. The input ADC sets up a phase lock loop and locks onto the frequency.
Video processing
From the digital video bus, the signal next goes to the frame memory in the Scaler IC (gm6015). Scaler manages
the frame buffer to perform frame rate conversion. The frame memory is asynchronous, meaning the input rate is
different than the output rate. From this point on the vertical and horizontal frequencies will not change. The frame
memory accepts information a page at a time.
When one page is displayed, another page is already in the frame buffer.
In the DVR5610, which has a native 1280 X 720 resolution, video inputs of 1280 X 720 and lower are converted
by the frame buffer to 75 Hz frame rate. The converted frames are then passed to the Scaler IC for resizing up to
1280 X 720. The DVR5610 does not resize images larger than 1280 X 720.
In the DVR5610 Zoom model, Higher resolution is first resized down to 1280 X 720 by dropping lines and pixels,
then converted by the frame buffer to 75 Hz frame rate, and finally passed to Scaler as 1280 X720 at 75 Hz. Video
inputs of resolutions lower than 800 x 600 are converted by the frame buffer to 75 Hz frame rate and passed to
the Scaler for resizing up to 1280 X720
The Scaler also provides the following support functions:
Dual digital video inputs for MAIN and PIP display
Dual bi- level / tri-level sync separators
”pixel-based” motion adaptive de-interlacing
2:2/3:2 inverse pull-down film processing
arbitrary shrink/zoom scaling on both MAIN and PIP channels
”3D” noise reduction filter
Color space conversion
Color controls
Video look up table(VLUT) and multi-image PIP display
The Scaler provides high-quality resizing of VGA, SVGA, NTSC, PAL and SECAM inputs up to the 1280 X720
display resolution.. Scaler also generates the display timing signals (Vsync, HSync, and blanking) that are passed
through the LVDS to the DMD Driver Circuit .
DCDi deinterlacing/enhancement chipset
By Using FLI2300 video processing of Faroudja , Its feature including DCDi deinterlacing, reverse 3:2 pulldown
film mode, motion adaptive 3D video noise reduction, cross-color artifact suppression and nonlinear
enhancement functions