How to print QR Image in thermal printer using flutter

I am using flutter blue and flutter_esc_pos_utils

I can print text but not images or QR. I wanna print Image(which is a QR CODE) that I have already generated.

Even with provided example in their documentation I didn't able to print QR here is my code for printing QR

void printWithDevice(BluetoothDevice device) async {
    final profile = await CapabilityProfile.load();
    final gen = Generator(PaperSize.mm58, profile);

    final printer = BluePrint();
    final ByteData data = await rootBundle.load('assets/images/qr.png');
    final Uint8List bytes = data.buffer.asUint8List();
    final img.Image image = img.decodeImage(bytes)!;
    printer.add(gen.image(image));               // does not work
    printer.add(gen.qrcode('www.google.com'));  // does not work 
    printer.add(gen.text('hello');              // works
    await printer.printData(device);
  }

Here is the implementation of BluePrint class which I got from here

class BluePrint {
  BluePrint({this.chunkLen = 512});

  final int chunkLen;
  final _data = List<int>.empty(growable: true);

  void add(List<int> data) {
    _data.addAll(data);
  }

  List<List<int>> getChunks() {
    final chunks = List<List<int>>.empty(growable: true);
    for (var i = 0; i < _data.length; i += chunkLen) {
      chunks.add(_data.sublist(i, min(i + chunkLen, _data.length)));
    }
    return chunks;
  }

  Future<void> printData(BluetoothDevice device) async {
    final data = getChunks();
    final characs = await _getCharacteristics(device);
    for (var i = 0; i < characs.length; i++) {
      if (await _tryPrint(characs[i], data)) {
        break;
      }
    }
  }

  Future<bool> _tryPrint(
    BluetoothCharacteristic charc,
    List<List<int>> data,
  ) async {
    for (var i = 0; i < data.length; i++) {
      try {
        await charc.write(data[i]);
      } catch (e) {
        return false;
      }
    }
    return true;
  }

  Future<List<BluetoothCharacteristic>> _getCharacteristics(
    BluetoothDevice device,
  ) async {
    final services = await device.discoverServices();
    final res = List<BluetoothCharacteristic>.empty(growable: true);
    for (var i = 0; i < services.length; i++) {
      res.addAll(services[i].characteristics);
    }
    return res;
  }
}

It's not work also by not working I mean it doesn't print anything at all

String qrData = "google.com";
const double qrSize = 200;
try {
  final uiImg = await QrPainter(
    data: qrData,
    version: QrVersions.auto,
    gapless: false,
  ).toImageData(qrSize);
  final dir = await getTemporaryDirectory();
  final pathName = '${dir.path}/qr_tmp.png';
  final qrFile = File(pathName);
  final imgFile = await qrFile.writeAsBytes(uiImg.buffer.asUint8List());
  final img = decodeImage(imgFile.readAsBytesSync());

  generator.image(img);
} catch (e) {
  print(e);
}

I have also tried this it's printed the string value of Image not image itself, is there anyway I can print image with that approach?

There is one more thing I would like to mention is while I was trying different thing I got weird print of question marks (??????) like this I got this image from here

I got that output two days ago I don't have my code now I'll have to check my local history to find out that code as I don't remember what I tried.

what Am I doing wrong?

Edit - I was trying something and I noticed when I pass simple text I have data in this line like [14,21,...]

 Future<bool> _tryPrint(
    BluetoothCharacteristic charc,
    List<List<int>> data,
  ) async {
    for (var i = 0; i < data.length; i++) {
      try {
        await charc.write(data[i]);
        print('printing data in chunck ${data[i]} and size ${data.length}');
      } catch (e) {
        return false;
      }
    }
    return true;
  } 

but when I pass the image I got 0,0,0,0.... maybe that could be a problem?

 printer.add(gen.image(image));  // does not work

this line didn't work because of two reasons -

1 - My printer does not support ESC* command,

2 - I did not pay attention to the width of the image,

Solutions -

1 - It worked with the GS v 0command like this gen.imageRaster(image);

2 - Image width 222 worked well for me.