TMtx.PixelDownSample Method

Summary

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

Class
TMtx

Declaration

Procedure PixelDownSample(Dst: TMtx; Pixels: integer = 500; Mode: TPixelDownSample = pdsPattern);

Description

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 Rows and 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).

Example 1

      Uses ..., MtxVecTee;
      var Mtx, ReducedMtx: TMtx;
      begin
        CreateIt(Mtx,ReducedMtx);
        try
          Mtx.Size(1000,1000,false);
          Mtx.RandGauss;
          // we're interested in averages, not pattern
          ReducedMtx.PixelDownSample(Mtx,200,pdsAverage);
          DrawIt(ReducedMtx);
        finally
          FreeIt(Mtx,ReducedMtx);
        end;
      end;