Steema Central

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procedure TForm1.Button1Click(Sender: TObject);
  Function GetChartJPEG(AChart:TCustomChart):TJPEGImage;
  var tmpBitmap:TBitmap;
      tmpChart: TChart;
      i:integer;
  begin
    result:=TJPEGImage.Create;   { <-- create a TJPEGImage }
    tmpBitmap:=TBitmap.Create;   { <-- create a temporary TBitmap }
    tmpChart := TChart.Create(AChart.Parent);

    try
      tmpChart.Assign(AChart);

      for i := 0 to AChart.SeriesCount - 1 do
        CloneChartSeries(AChart.Series[i]).ParentChart := tmpChart;

      tmpChart.Width := trunc(AChart.Width*1.25);
      tmpChart.Height := trunc(AChart.Height*1.25);

      tmpBitmap.Width :=tmpChart.Width;   { <-- set the bitmap dimensions }
      tmpBitmap.Height:=tmpChart.Height;
      { draw the Chart on the temporary Bitmap... }
      tmpChart.Draw(tmpBitmap.Canvas,Rect(0,0,tmpBitmap.Width,tmpBitmap.Height));
      { set the desired JPEG options... }
      With result do
      begin
        GrayScale            :=False;
        ProgressiveEncoding  :=True;
        CompressionQuality   :=95;  // % 0 - 100
        PixelFormat          :=jf24bit;  // or jf8bit
        ProgressiveDisplay   :=True;
        Performance          :=jpBestQuality;  // or jpBestSpeed
        Scale                :=jsFullSize;  // or jsHalf, jsQuarter, jsEighth
        Smoothing            :=True;
        { Copy the temporary Bitmap onto the JPEG image... }
        Assign(tmpBitmap);
      end;
    finally
      tmpBitmap.Free;  { <-- free the temporary Bitmap }
      tmpChart.Free;
    end;
  end;

begin
  With GetChartJPEG(Chart1) do
  try
    SaveToFile('C:\tmp\myJPEGChart.jpg');    { <-- save the JPEG to disk }
  finally
    Free;  { <-- free the temporary JPEG object }
  end;
end;