Re: How to convert a bitmap to Base64 string with Indy?

without using INDY you can do it directly in code as follows


uses
  EncdDecd, zlib;

function CompressAndEncode(const input: string): string;
var
  fCompressedStream: TMemoryStream;
  fStreamCompressor: TCompressionStream;
  fStringStream: TStringStream;
begin
  fCompressedStream := TMemoryStream.Create;
  try
    fStreamCompressor := TCompressionStream.Create(clDefault, fCompressedStream);
    try
      fStreamCompressor.Write(input[1], length(input));
    finally
      FreeAndNil(fStreamCompressor);
    end;
    fStringStream := TStringStream.create('');
    try
      fCompressedStream.Position := 0;
      EncodeStream(fCompressedStream, fStringStream);
      Result := fStringStream.datastring;
    finally
      FreeAndNil(fStringStream);
    end;
  finally
    FreeAndNil(fCompressedStream);
  end;
end;

function DecodeAndUnCompress(const input: string): string;
var
  fWorkStream: TMemoryStream;
  fEncodedStream: TMemoryStream;
  fStreamDeCompressor: TDeCompressionStream;
  fBufLen: integer;
  fBuffer: array[0..16383] of byte;
begin

  fWorkStream := TMemoryStream.create;
  try
    fWorkStream.size := length(input);
    move(input[1], fWorkStream.memory^, fWorkStream.size);
    fWorkStream.position := 0;
    fEncodedStream := TMemoryStream.create;
    try
      DecodeStream(fWorkStream, fEncodedStream);
      fWorkStream.size := 0;
      fEncodedStream.position := 0;
      fStreamDeCompressor := TDeCompressionStream.create(fEncodedStream);
      try
        fBufLen := fStreamDeCompressor.Read(fBuffer, SizeOf(fBuffer));
        while fBufLen > 0 do
        begin
          fWorkStream.Write(fBuffer, fBufLen);
          fBufLen := fStreamDeCompressor.Read(fBuffer, SizeOf(fBuffer));
        end;
      finally
        FreeAndNil(fStreamDeCompressor);
      end;
    finally
      FreeAndnil(fEncodedStream);
    end;
    fWorkStream.position := 0;
    SetLength(Result, fWorkStream.size);
    move(fWorkStream.memory^, Result[1], fWorkStream.size);
  finally
    FreeAndNil(fWorkStream);
  end;

end;

procedure TForm1.Button1Click(Sender: TObject);
var
  bmp: TBitmap;
  mStream: TMemoryStream;
  i: Integer;
  s, s64: string;
  b: byte;
  ts: TStringlist;
begin
  if OpenPictureDialog1.execute then
  begin
    bmp := TBitmap.Create;
    bmp.LoadFromFile(OpenPictureDialog1.FileName);
    mStream := TMemoryStream.Create;
    try
      bmp.SaveToStream(mStream);
      mStream.Position := 0;
      for i := 0 to mStream.size do
      begin
        mStream.read(b,1);
        s64 := s64 + char(b);
      end;

      s := CompressAndEncode(s64);
      ts := TStringlist.create;
      ts.add(s);
      ts.SaveToFile('test.b64');
      ts.free;

    finally
      bmp.Free;
      mStream.Free;
    end;
  end;
end;

procedure TForm1.Button2Click(Sender: TObject);
var
  bmp: TBitmap;
  mStream: TMemoryStream;
  s, s64: string;
begin
  with TStringlist.create do
  begin
    loadfromfile('test.b64');
    s64 := Text;
    free;
  end;
  s := DecodeAndUnCompress(s64);
  mStream := TMemoryStream.Create;
  mStream.WriteBuffer(s[1],length(s));
  bmp := TBitmap.Create;
  mstream.Position := 0;
  bmp.LoadFromStream(mstream);
//  bmp.SaveToFile('test.bmp');
  mstream.free;
  Image1.Picture.Bitmap := bmp;
  bmp.free;
end;