procedure TForm1.btnExportFFTImageClick(Sender: TObject);
var
  Y, X, Size: Integer;
  Filestream: TFileStream;
  ImageData: TMemoryStream;
  PixelColor: TIEComplexColor;

begin                    //FTImage
  try
    FTImageCopy := ImageEnView1.Proc.FTCreateImage( ieitRGB ,-1,-1 );
    ImageData := TMemoryStream.Create;

    FileStream := TFileStream.Create(OriginalFileDir + '\FFT_' + ChangeFileExt(OriginalFileName, '.FTI'), fmCreate);
    try
      //Size would be (I think) Width x Height x 3(colors) x 2 (real & imag):
      Size := FTImageCopy.ComplexWidth * FTImageCopy.ComplexHeight * 3 * 2;
      ImageData.Write(Size, SizeOf(Integer));
      ImageData.Write(FTImageCopy.Imagetype, SizeOf(TIEFtImageType));
      ImageData.Write(FTImageCopy.ComplexWidth, SizeOf(Integer));
      ImageData.Write(FTImageCopy.ComplexHeight, SizeOf(Integer));

      try
        for Y := 0 to FTImageCopy.ComplexHeight - 1 do
          begin
            for X := 0 to FTImageCopy.ComplexWidth - 1 do
              begin
                PixelColor := FTImageCopy.ComplexPixel[X, Y];
                //Write Red:
                ImageData.Write(PixelColor.real_Red, SizeOf(PIEsingle));
                ImageData.Write(PixelColor.imag_Red, SizeOf(PIEsingle));
                //Write Blue:
                ImageData.Write(PixelColor.real_Blue, SizeOf(PIEsingle));
                ImageData.Write(PixelColor.imag_Blue, SizeOf(PIEsingle));
                //Write Green:
                ImageData.Write(PixelColor.real_Green, SizeOf(PIEsingle));
                ImageData.Write(PixelColor.imag_Green, SizeOf(PIEsingle));
              end;
          end;
      finally
        if(ImageData.Position > 0) then
          begin
            ImageData.Position := 0;
            FileStream.CopyFrom(ImageData, 0);
          end;
      end;

    finally
      FileStream.Free;
      FTImageCopy.Free;
    end;
  except
    on E: Exception do
      Writeln('Error: ', E.Message);
  end;
end;


then another procedure that reads it back:


procedure TForm1.btnLoadFFTClick(Sender: TObject);
begin
  if(OpenFFTAsBitmapDialog1.Execute) then
    begin
      try
        if assigned(FTImage) then
          FTImage.Free;

        LoadFTImageFromFile(OpenFFTAsBitmapDialog1.FileName, FTImage);

        if assigned(FTImage) then
          begin
            ImageEnView2.Proc.FTDisplayFrom(FTImage);
          end;
      finally
        FTImage.Free;
      end;
    end;
end;

procedure TForm1.LoadFTImageFromFile(const FileName: String; var LoadedImage: TIEFTImage);
var
  FileStream: TFileStream;
  ImageData: TMemoryStream;
  X, Y: Integer;
  tmpImageEnView: TImageEnView;
  ImageType: TIEFtImageType;
  Size, Width, Height: Integer;
  ExpectedSize: Integer;

begin
  try
    FileStream := TFileStream.Create(FileName, fmOpenRead);
    ImageData := TMemoryStream.Create;
    try
      // Load data from the file into ImageData
      ImageData.CopyFrom(FileStream, 0);
      ImageData.Position := 0;

      // Read the size of the data
      ImageData.Read(Size, SizeOf(Integer));
      // Read other metadata if needed
      ImageData.Read(ImageType, SizeOf(TIEFtImageType));
      ImageData.Read(Width, SizeOf(Integer));
      ImageData.Read(Height, SizeOf(Integer));

      //Temp:
      tmpImageEnView := TImageEnView.Create(self);

      LoadedImage := tmpImageEnView.Proc.FTCreateImage(ImageType, -1 -1);

      try
        // Load pixel data
        for Y := 0 to Height - 1 do
        begin
          for X := 0 to Width - 1 do
          begin
            ImageData.Read(LoadedImage.ComplexPixel[X, Y].real_Red^, SizeOf(PIEsingle));
            ImageData.Read(LoadedImage.ComplexPixel[X, Y].imag_Red^, SizeOf(PIEsingle));
            ImageData.Read(LoadedImage.ComplexPixel[X, Y].real_Blue^, SizeOf(PIEsingle));
            ImageData.Read(LoadedImage.ComplexPixel[X, Y].imag_Blue^, SizeOf(PIEsingle));
            ImageData.Read(LoadedImage.ComplexPixel[X, Y].real_Green^, SizeOf(PIEsingle));
            ImageData.Read(LoadedImage.ComplexPixel[X, Y].imag_Green^, SizeOf(PIEsingle));
          end;
        end;

        // Now, you have the data loaded into LoadedImage
        // You can use LoadedImage as needed
      except
        LoadedImage.Free;
        raise; // Re-raise the exception
      end;
    finally
      ImageData.Free;
      FileStream.Free;
      tmpImageEnView.Free;
    end;
  except
    on E: Exception do
      Writeln('Error: ', E.Message);
  end;
end;

procedure TForm1.SaveFTImageToFile(const FileName: String);
var
  Y, X, Size: Integer;
  Filestream: TFileStream;
  ImageData: TMemoryStream;
  LoadedImage: TIEFTImage;
  PixelColor: TIEComplexColor;

begin
  try
    case rgImgType.ItemIndex of
      0: LoadedImage := ImageEnView1.Proc.FTCreateImage(ieitRGB, -1, -1);
      1: LoadedImage := ImageEnView1.Proc.FTCreateImage(ieitGrayscale, -1, -1);
    end;

    ImageData := TMemoryStream.Create;

    FileStream := TFileStream.Create(OriginalFileDir + '\FFT_' + ChangeFileExt(OriginalFileName, '.FTI'), fmCreate);
    try
      if(rgImgType.ItemIndex = 0) then
          begin
              //RGB Size would be (I think) Width x Height x 3(colors) x 2 (real & imag):
              Size := LoadedImage.ComplexWidth * LoadedImage.ComplexHeight * 3 * 2;
          end
       else
          begin
              //Grayscale Size would be (I think) Width x Height x 1(colors) x 2 (real & imag):
              Size := LoadedImage.ComplexWidth * LoadedImage.ComplexHeight * 1 * 2; 
          end;
      ImageData.Write(Size, SizeOf(Integer));
      ImageData.Write(LoadedImage.Imagetype, SizeOf(TIEFtImageType));
      ImageData.Write(LoadedImage.ComplexWidth, SizeOf(Integer));
      ImageData.Write(LoadedImage.ComplexHeight, SizeOf(Integer));

      try
        for Y := 0 to LoadedImage.ComplexHeight - 1 do
          begin
            for X := 0 to LoadedImage.ComplexWidth - 1 do
              begin
                PixelColor := LoadedImage.ComplexPixel[X, Y];
                case LoadedImage.Imagetype of
                  ieitRGB:
                    begin
                      //Write Red:
                      ImageData.Write(PixelColor.real_Red^, SizeOf(Single));
                      ImageData.Write(PixelColor.imag_Red^, SizeOf(Single));

                      //Write Green:
                      ImageData.Write(PixelColor.real_Green^, SizeOf(Single));
                      ImageData.Write(PixelColor.imag_Green^, SizeOf(Single));

                      //Write Blue:
                      ImageData.Write(PixelColor.real_Blue^, SizeOf(Single));
                      ImageData.Write(PixelColor.imag_Blue^, SizeOf(Single));
                    end;

                  ieitGrayscale:
                    begin
                      //Write Gray:
                      ImageData.Write(PixelColor.real_gray^, SizeOf(Single));
                      ImageData.Write(PixelColor.imag_gray^, SizeOf(Single));
                    end;
                end;
              end;
          end;
      finally
        if(ImageData.Position > 0) then
          begin
            ImageData.Position := 0;
            FileStream.CopyFrom(ImageData, 0);
          end;
      end;

    finally
      FileStream.Free;
      ImageData.Free;
    end;
  except
    on E: Exception do
      Writeln('Error: ', E.Message);
  end;
end;

procedure TForm1.LoadFTImageFromFile(const FileName: String);
var
  FileStream: TFileStream;
  ImageData: TMemoryStream;
  tmpSingle: Single;
  X, Y: Integer;
  ImageType: TIEFtImageType;
  Size, Width, Height: Integer;
  ExpectedSize: Integer;

begin
  try
    FileStream := TFileStream.Create(FileName, fmOpenRead);
    ImageData := TMemoryStream.Create;
    try
      // Load data from the file into ImageData
      ImageData.CopyFrom(FileStream, 0);
      ImageData.Position := 0;

      // Read the size of the data
      ImageData.Read(Size, SizeOf(Integer));
      // Read other metadata if needed
      ImageData.Read(ImageType, SizeOf(TIEFtImageType));
      ImageData.Read(Width, SizeOf(Integer));
      ImageData.Read(Height, SizeOf(Integer));

      //Temp:
      FTImage := ImageEnView1.Proc.FTCreateImage(ImageType, Width, Height);


      try
        // Load pixel data
        for Y := 0 to Height - 1 do
        begin
          for X := 0 to Width - 1 do
          begin
            case ImageType of
              ieitRGB:
                begin
                  //Read real_Red:
                  ImageData.Read(tmpSingle, SizeOf(Single));
                  FTImage.ComplexPixel[X, Y].real_Red^ := tmpSingle;
                  //Read imag_Red:
                  ImageData.Read(tmpSingle, SizeOf(Single));
                  FTImage.ComplexPixel[X, Y].imag_Red^ := tmpSingle;

                  //Read real_Green:
                  ImageData.Read(tmpSingle, SizeOf(Single));
                  FTImage.ComplexPixel[X, Y].real_Green^ := tmpSingle;
                  //Read imag_Green:
                  ImageData.Read(tmpSingle, SizeOf(Single));
                  FTImage.ComplexPixel[X, Y].imag_Green^ := tmpSingle;

                  //Read real_Blue:
                  ImageData.Read(tmpSingle, SizeOf(Single));
                  FTImage.ComplexPixel[X, Y].real_Blue^ := tmpSingle;
                  //Read imag_Blue:
                  ImageData.Read(tmpSingle, SizeOf(Single));
                  FTImage.ComplexPixel[X, Y].imag_Blue^ := tmpSingle;
                end;

              ieitGrayscale:
                begin
                  //Read real_gray:
                  ImageData.Read(tmpSingle, SizeOf(Single));
                  FTImage.ComplexPixel[X, Y].real_gray^ := tmpSingle;

                  //Read imag_gray:
                  ImageData.Read(tmpSingle, SizeOf(Single));
                  FTImage.ComplexPixel[X, Y].imag_gray^ := tmpSingle;
                end;
            end;
          end;
        end;

        // Now, you have the data loaded into LoadedImage
        // You can use LoadedImage as needed
      except
        raise; // Re-raise the exception
      end;
    finally
      ImageData.Free;
      FileStream.Free;
      //tmpImageEnView.Free;
    end;
  except
    on E: Exception do
      Writeln('Error: ', E.Message);
  end;
end;