Converts image transformation maps from one representation to another

[dstmap1, dstmap2] = cv.convertMaps(map1, map2)
[dstmap1, dstmap2] = cv.convertMaps(map1)
[...] = cv.convertMaps(..., 'OptionName',optionValue, ...)

Input

• map1 The first input map of either (x,y) points or just x values of the transformation having the type int16 (MxNx2), single (MxN), or single (MxNx2).
• map2 The second input map of y values of the transformation having the type uint16 (MxN) or single (MxN), or none (empty map if map1 is (x,y) points), respectively.

Output

• dstmap1 The first output map that has the type specified by DstMap1Type and the same row/col size as src. See details below.
• dstmap2 The second output map. See details below.

Options

• DstMap1Type Type of the first output map. The default value of -1 chooses an appropriate type depending on the direction of conversion. So if map1 is in fixed-point representation, the output type is single2 (for combined floating-point representation), otherwise if map1 is in floating-point representation, the output type is int16 (for fixed-point representation). Accepted types are:
  • int16 first output map is a MxNx2 int16 array
  • single1 first output map is a MxNx1 single matrix
  • single2 first output map is a MxNx2 single matrix
• NNInterpolation Flag indicating whether the fixed-point maps are used for the nearest-neighbor or for a more complex interpolation. If this flag is true, the second output will be empty. default false

The function converts a pair of maps for cv.remap from one representation to another. The following options (map1, map2) -> (dstmap1, dstmap2) are supported (in terms of class and number of channels of maps):

• (single 1-cn, single 1-cn) -> (int16 2-cn, uint16 1-cn): This is the most frequently used conversion operation, in which the original floating-point maps (see cv.remap) are converted to a more compact and much faster fixed-point representation. The first output array contains the rounded coordinates and the second array (created only when NNInterpolation=false) contains indices in the interpolation tables.

• (single 2-cn, []) -> (int16 2-cn, uint16 1-cn): The same as above but the original maps are stored in one 2-channel matrix.

• (int16 2-cn, uint16 1-cn) -> (single 1-cn, single 1-cn) or (int16 2-cn, uint16 1-cn) -> (single 2-cn, []): Reverse conversion. Obviously, the reconstructed floating-point maps will not be exactly the same as the originals.