NvMedia2DLdcWarpMapParameters Struct Reference

Detailed Description

Holds the NvMedia definition of an LDC Warp Map.

Warp Map stores the mappings of each control point from destination image to input image. The coordinates of control points in a destination image are defined by regionParams.

If warp map region N has controlPointXSpacingLog2[N] = 0 it is considered to have "full columns", and with controlPointYSpacingLog2[N] = 0 "full rows". Otherwise, the region has "sparse columns/rows".

The warp map processing always operates on "tiles" of size NvMedia2DCapabilities::tileWidth x NvMedia2DCapabilities::tileHeight pixels. When determining the number of control points in warp map region N, regionWidth[N] is rounded up to the next multiple of tile width and regionHeight[N] to the next multiple of tile height.

In a warp map region with full columns/rows, the number of columns/rows of control points equals the tile size rounded up width/height of the region.

In a warp map region with sparse columns/rows,

• First control point column/row is at position 0 within the region.
• There's always an odd number of columns/rows of control points.
• The position of the last control point column/row is always outside the tile size rounded up width/height of the region.

For example, if region width is 192 and control point interval is 64, it will result in 5 columns of control points with X-coordinates 0, 64, 128, 192 and 256.

The code below shows how to calculate the exact number of control points for a single region:

NvMedia2DCapabilities caps;
NvMedia2DLdcRegionParameters regionInfo;
...
w = RoundUp(regionInfo.regionWidth[i], caps.tileWidth);
dx = 1 << regionInfo.controlPointXSpacingLog2[i];
numColumns = RoundUp(w, 2 * dx) / dx + (dx == 1 ? 0 : 1);
 
h = RoundUp(regionInfo.regionHeight[i], caps.tileHeight);
dy = 1 << regionInfo.controlPointYSpacingLog2[i];
numRows = RoundUp(h, 2 * dy) / dy + (dy == 1 ? 0 : 1);

Where RoundUp() rounds the first argument up to the nearest multiple of the second argument.

See also

NvMedia2DCapabilities

NvMedia2DLdcRegionParameters

NvMedia2DFillLdcWarpMap()

NvMedia2DSetSrcLdcTransformMatrix()

Definition at line 829 of file nvmedia_2d.h.

Collaboration diagram for NvMedia2DLdcWarpMapParameters:

Data Fields
NvMedia2DLdcRegionParameters	regionParams
	Specifies the regions paramters. More...
uint32_t	numControlPoints
	Number of control points in the controlPoints array. More...
const NvMedia2DLdcControlPoint *	controlPoints
	Array of control points across all the regions stored in a row-major order. More...

Field Documentation

controlPoints

const NvMedia2DLdcControlPoint* NvMedia2DLdcWarpMapParameters::controlPoints

Array of control points across all the regions stored in a row-major order.

Definition at line 842 of file nvmedia_2d.h.

numControlPoints

uint32_t NvMedia2DLdcWarpMapParameters::numControlPoints

Number of control points in the controlPoints array.

Must equal the number of control points specified by regionParams.

Definition at line 838 of file nvmedia_2d.h.

regionParams

NvMedia2DLdcRegionParameters NvMedia2DLdcWarpMapParameters::regionParams

Specifies the regions paramters.

Definition at line 832 of file nvmedia_2d.h.

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The documentation for this struct was generated from the following file:

• nvmedia_2d.h