Matrix.PixelDownSample Method

Matrix Class

procedure PixelDownSample(Dst: TMtx; Pixels: Integer; mode: TPixelDownSample);

Creates a reduced size dense matrix for screen display (bitmap) to show the matrix pattern.

#NameTypeDescription
1DstTMtxsource TMtx
2PixelsInteger
3modeTPixelDownSample

Result: stored in self (calling object)

Remarks:

Creates a reduced size dense matrix for screen display (bitmap) to show the matrix pattern. Pixels parameter defines the target number of pixels to reduce Matrix.Rows and Matrix.Cols to. The size reduction method depends on what you want to see:

  • pdsPattern , Returns 1 for all areas with at least one nonzero value regardless of its amplitude.
  • pdsAverage, Average all values within an area (pixel).
  • pdsPeak, Return only the maximum absolute value within an area (region will become one pixel).
Examples
Uses ..., MtxVecTee;
var Mtx, ReducedMtx: Matrix;
begin
    Mtx.Size(1000,1000,false);
    Mtx.RandGauss;
    // we're interested in averages, not pattern
    ReducedMtx.PixelDownSample(Mtx,200,pdsAverage);
    DrawIt(ReducedMtx);
end;