NvMediaLdcWarpMapParameters Struct Reference

Detailed Description

Holds the NvMedia LDC definition of a 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 64x16 pixel tiles, so when determining the number of control points in warp map region N, regionWidth[N] is rounded up to the next multiple of 64 and regionHeight[N] to the next multiple of 16.

In a warp map region with full columns/rows, the number of columns/rows of control points equals the 64x16 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 64x16 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:

NvMediaLdcRegionParameters regionInfo;
...
w = RoundUp(regionInfo.regionWidth[i], 64);
dx = 1 << regionInfo.controlPointXSpacingLog2[i];
numColumns = RoundUp(w, 2 * dx) / dx + (dx == 1 ? 0 : 1);
 
h = RoundUp(regionInfo.regionHeight[i], 16);
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

NvMediaLdcRegionParameters

NvMediaLdcSetWarpMapParameters()

Definition at line 438 of file nvmedia_ldc.h.

Collaboration diagram for NvMediaLdcWarpMapParameters:

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

Field Documentation

controlPoints

const NvMediaLdcControlPoint* NvMediaLdcWarpMapParameters::controlPoints

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

Definition at line 451 of file nvmedia_ldc.h.

numControlPoints

uint32_t NvMediaLdcWarpMapParameters::numControlPoints

Number of control points in the controlPoints array.

Must equal the number of control points specified by regionParams.

Definition at line 447 of file nvmedia_ldc.h.

regionParams

NvMediaLdcRegionParameters NvMediaLdcWarpMapParameters::regionParams

Specifies the regions paramters.

Definition at line 441 of file nvmedia_ldc.h.

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

• nvmedia_ldc.h