Invalid character when displaying Image in base64 string from express server to flutter

Question

I'm trying to send image data from my nodejs express server to flutter. I receive the image data as a buffer from another server Appwrite and decode it to base64 string then send the string which upon receiving it on my flutter app, i try to decode it and display the image but displaying fails with error message

Server side

const getPhoto = async function(req, res){
    var data = await api.getStorage().getFilePreview('61579ced0');
    console.log("raw data -------------------------------\n")
    console.log(data);
    var base64 = data.toString('base64');
    console.log("base 64 data -------------------------------\n")
    console.log(base64);
    
    var obj = new Object();
    obj['data'] = base64;
    res.send(obj);
};

Raw data format

below is the output of console.log(data);

in encoded form(base 64)

below is the output of var base64 = data.toString('base64');

Flutter side

model

@JsonSerializable()
    class ImageResponse {
    
      String data;
    
      ImageResponse(this.data);
    
      factory ImageResponse.fromJson(Map<String, dynamic> json) =>
          _$ImageResponseFromJson(json);
    
      Map<String, dynamic> toJson() => _$ImageResponseToJson(this);
    
      Uint8List getImage() {
        return base64Decode(data);
      }
    }

displaying the image

FutureBuilder<Uint8List>(
                      future: bloc.getPhoto(),
                              builder: (BuildContext context,
                                  AsyncSnapshot<Uint8List> snapshot) {
                                if (snapshot.hasData) {
                                  return Image.memory(snapshot.data);
                                } else {
                                  return FittedBox(
                                    fit: BoxFit.contain,
                                    child: Image.asset(
                                      'assets/images/placeholder.jpg',
                                    ),
                                  );
                                }
                              })