Geometry Adjustment Principle - Barco MCM-400 HFR User Manual

9.1.1

Geometry adjustment principle

Description
Geometry adjustment enables the relocation of pixel groups in an image in order to introduce spacial distortion. To make the
procedure comprehensible, there are some rules and features.
The use of geometry adjustment leads to image quality loss! The more geometry adjustment is applied, the
more quality loss.
To considerably reduce the labour intensiveness and complexity of geometry adjustment it is not possible to grab any pixel of the
image and move it to a new position. Instead we have a limited set of pixels that can be relocated: the so called anchor points.
Moving an anchor point causes pixels in the same region to be moved gradually with this one pixel, depending on their distance to it.
The size of the region of impact depends on the anchor point: some anchor pixels have impact on the full image, while others have
impact on a small area only. The full image is divided in 33 x 33 regions. The smallest region of impact is one of these 99 regions.
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Image 9-1
SIM 10: 33 x 33 regions in an image
Geometry adjustment is divided in six modes:
• 2 x 2 (highest mode);
• 3 x 3;
• 5 x 5;
• 9 x 9;
• 17 x 17;
• 33 x 33 (lowest mode).
The six modes represent 21 levels, each level representing its own group of anchor points.
Level 4 Level 5
Level 7 Level 8
Level 11 Level 12 Level 13
Level 16
Image 9-2
Level hierarchy
The hierarchy of these levels is very important: each level interacts with all lower levels. Adjusting a point on a certain level affects
the points in all or some of the lower levels. The impact depends on the level itself. Therefore it is important to adjust the geometry
R5909056 MCM-400 HFR 11/05/2016
8 9 10 11 12 13 14 15 16 17 18 19 20
2 x 2
Level 1
3 x 3
Level 2 Level 3
5 x 5
Level 6
Level 9
9 x 9
Level 10
Level 14 Level 15
Level 17 Level 18
Level 19 Level 20
Level 21
21 22 23 24 25 26 27 28 29 30 31 32
17 x 17
33 x 33
9. Advanced operation
93