WarpAffineQuad

Syntax

Parameters

pSrc	Pointer to the source image origin. An array of separate pointers to each plane in case of data in planar format.
srcSize	Size in pixels of the source image.
srcStep	Distance in bytes between starts of consecutive lines in the source image buffer.
srcRoi	Region of interest in the source image (of the IppiRect type).
srcQuad	A given quadrangle in the source image.
pDst	Pointer to the destination image origin. An array of separate pointers to each plane in case of data in planar format.
dstStep	Distance in bytes between starts of consecutive lines in the destination image buffer.
dstRoi	Region of interest in the destination image (of the IppiRect type).
dstQuad	A given quadrangle in the destination image.
interpolation	Specifies the interpolation mode. Use one of the following: IPPI_INTER_NN nearest neighbor interpolation IPPI_INTER_LINEAR linear interpolation IPPI_INTER_CUBIC cubic interpolation IPPI_SMOOTH_EDGE use edge smoothing in addition to one of the above modes.

Description

The function ippiWarpAffineQuad is declared in the ippi.h file. It operates with ROI (see ROI Processing in Geometric Transforms).

This function applies the affine transform to an arbitrary quadrangle srcQuad in the source image pSrc. The operations take place only inside the intersection of the source image ROI srcRoi and the source quadrangle. The function ippiWarpAffineQuad uses the same formulas for pixel mapping as in the case of the ippiWarpAffine function. Transform coefficients are computed internally, based on the mapping of the source quadrangle to the quadrangle dstQuad specified in the destination image pDst. The dstQuad should have a non-empty intersection with the destination image ROI dstRoi. The function computes the coordinates of the 4th vertex of the destination quadrangle that uniquely depends on the three other vertices. If the computed coordinates are not equal to the ones specified in dstQuad, the function returns the warning message and continues operation with the computed values.

The first dimension [4] of the array specifying the quadrangle srcQuad[4][2] or dstQuad[4][2] is equal to the number of vertices, and the second dimension [2] holds x and y coordinates of the vertex.

Edge smoothing interpolation is applicable only if the source quadrangle lies in the source image ROI.

Return Values

ippStsNoErr	Indicates no error. Any other value indicates an error or a warning.
ippStsNullPtrErr	Indicates an error condition if one of the specified pointers is NULL.
ippStsSizeErr	Indicates an error condition if any image dimension has zero or negative value.
ippStsStepErr	Indicates an error condition if srcStep or dstStep has a zero or negative value.
ippStsInterpolationErr	Indicates an error condition if interpolation has an illegal value.
ippStsQuadErr	Indicates an error condition if srcQuad or dstQuad degenerates into triangle, line, or point, or if dstQuad has wrong vertex coordinates.
ippStsWrongIntersectROIErr	Indicates an error condition if srcRoi has no intersection with the source image.
ippStsWrongIntersectQuad	Indicates a warning that no operation is performed if the srcRoi has no intersection with the srcQuad, or dstRoi has no intersection with the dstQuad.
ippStsAffineQuadChanged	Indicates a warning that coordinates of the 4th vertex of the destination quadrangle dstQuad are corrected by the function.