QG82945GSE S LB2R Intel, QG82945GSE S LB2R Datasheet - Page 371

• Manufacturer Part Number: QG82945GSE S LB2R
• Description: GRAPHICS AND MEM CNTRL HUB; No. of Pins: 998; Package / Case: FCBGA; Interface Type: PCI, SATA, USB
• Manufacturer: Intel

Functional Description
10.4.1.7
10.4.1.7.1
10.4.1.7.2
10.4.1.7.3
10.4.1.7.4
Datasheet
The (G)MCH has instructions to invoke BLT and stretch BLT operations, permitting
software to set up instruction buffers and use batch processing. The (G)MCH can
perform hardware clipping during BLTs.
Video Engine
Hardware Motion Compensation
The Motion Compensation (MC) process consists of reconstructing a new picture by
predicting (either forward, backward or bidirectionally) the resulting pixel colors from
one or more reference pictures. The (G)MCH receives the video stream and implements
Motion Compensation and subsequent steps in hardware. Performing Motion
Compensation in hardware reduces the processor demand of software-based MPEG-2
decoding, and thus improves system performance.
The Motion Compensation functionality is overloaded onto the texture cache and
texture filter. The texture cache is used to typically access the data in the
reconstruction of the frames and the filter is used in the actual motion compensation
process. To support this overloaded functionality the texture cache additionally
supports the following input format: YUV420 planar
4-Channel MPEG YUV
The peformance of present generation IGD is significantly faster than that of the
previous generations.
Sub-Picture Support
Sub-picture is used for two purposes, one is Subtitles for movie captions, etc. (which
are superimposed on a main picture), and Menus used to provide some visual operation
environments the user of a content player.
DVD allows movie subtitles to be recorded as Sub-pictures. On a DVD disc, it is called
“Subtitle” because it has been prepared for storing captions. Since the disc can have a
maximum of 32 tracks for Subtitles, they can be used for various applications, for
example, as Subtitles in different languages or other information to be displayed.
There are two kinds of Menus, the System Menus and other In-Title Menus. First, the
System Menus are displayed and operated at startup of or during the playback of the
disc or from the stop state. Second, In-Title menus can be programmed as a
combination of Sub-picture and Highlight commands to be displayed during playback of
the disc.
The (G)MCH supports sub-picture for DVD and DBS by mixing the two video streams
via alpha blending. Unlike color keying, alpha blending provides a softer effect and each
pixel that is displayed is a composite between the two video stream pixels. The (G)MCH
can utilize four methods when dealing with sub-pictures. The flexibility enables the
(G)MCH to work with all sub- picture formats.
De-interlacing Support
For display on a progressive computer monitor, interlaced data that has been formatted
for display on interlaced monitors (TV), needs to be de-interlaced. The simple
approaches to de-interlacing create unwanted display artifacts. More advanced de-
interlacing techniques have a large cost associated with them. The compromise
solution is to provide a low cost but effective solution and enable both hardware and
software based external solutions. Software based solutions are enabled through a high
bandwidth transfer to system memory and back.
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