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CreatePerspectiveMap_Points
Header: | AVL.h |
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Namespace: | avl |
Creates a perspective transform map from four points denoting a rectangle in the world coordinates.
Syntax
void avl::CreatePerspectiveMap_Points ( const avl::ImageFormat& inImageFormat, atl::Optional<const avl::Region&> inRoi, const atl::Array<avl::Point2D>& inImagePoints, atl::Optional<const atl::Array<avl::Point2D>&> inTargetPoints, atl::Optional<const avl::Size&> inNewSize, const avl::InterpolationMethod::Type inInterpolationMethod, avl::SpatialMap& outSpatialMap, avl::Matrix& outTransformMatrix )
Parameters
Name | Type | Default | Description | |
---|---|---|---|---|
inImageFormat | const ImageFormat& | |||
inRoi | Optional<const Region&> | NIL | Range of pixels to be processed | |
inImagePoints | const Array<Point2D>& | Points define real object plane corners. | ||
inTargetPoints | Optional<const Array<Point2D>&> | NIL | Points define target plane corners. If NIL then image corners are used starting from (0,0) (Width, 0) (Width, Height), (0, Height) | |
inNewSize | Optional<const Size&> | NIL | New image size after remapping | |
inInterpolationMethod | const InterpolationMethod::Type | Interpolation method used in extraction of image pixel values | ||
outSpatialMap | SpatialMap& | Created SpatialMap with perspective transform | ||
outTransformMatrix | Matrix& | Used transform matrix |
Examples
Remarks
This filter is a good choice for local perspective distortion removal - such as "unwrapping" boxes, as is depicted by the example above. Applications concerned with observing real-world flat surfaces (such as observing conveyor belts) should use methods that are more accurate. Please refer to: Machine Vision Guide - Camera Calibration and World Coordinates
Notice that both inImagePoints array and inTargetPoints must be made of four points. This filter creates point to point transform so changing the points' order in the array may yield an unexpected result.
The best way to understand the relation between inImagePoints and inTargetPoints is to present the first of them on the input image and the second on the background of the remapped image.
Errors
List of possible exceptions:
Error type | Description |
---|---|
DomainError | Each of input array must contain four points in CreatePerspectiveMap_Points |
See Also
- CreatePerspectiveMap_Path – Creates a perspective transform map from planes defined by paths.
- RemapImage – Applies a precomputed image transform, defined by a spatial map object.