You can create bitmap from byteBuffer, that can be received by call the method getByteBuffer().In the offical quick start example of ML Kit Vission you can find the vay how to achieve this. Below is a piece of code that can solve your problem:
Method getBitmap() thats converts NV21 format byte buffer to bitmap:

@Nullable
  public static Bitmap getBitmap(ByteBuffer data, FrameMetadata metadata) {
    data.rewind();
    byte[] imageInBuffer = new byte[data.limit()];
    data.get(imageInBuffer, 0, imageInBuffer.length);
    try {
      YuvImage image =
          new YuvImage(
              imageInBuffer, ImageFormat.NV21, metadata.getWidth(), metadata.getHeight(), null);
      ByteArrayOutputStream stream = new ByteArrayOutputStream();
      image.compressToJpeg(new Rect(0, 0, metadata.getWidth(), metadata.getHeight()), 80, stream);

      Bitmap bmp = BitmapFactory.decodeByteArray(stream.toByteArray(), 0, stream.size());

      stream.close();
      return rotateBitmap(bmp, metadata.getRotation(), false, false);
    } catch (Exception e) {
      Log.e("VisionProcessorBase", "Error: " + e.getMessage());
    }
    return null;
  }

Method rotateBitmap():

private static Bitmap rotateBitmap(
      Bitmap bitmap, int rotationDegrees, boolean flipX, boolean flipY) {
    Matrix matrix = new Matrix();

    // Rotate the image back to straight.
    matrix.postRotate(rotationDegrees);

    // Mirror the image along the X or Y axis.
    matrix.postScale(flipX ? -1.0f : 1.0f, flipY ? -1.0f : 1.0f);
    Bitmap rotatedBitmap =
        Bitmap.createBitmap(bitmap, 0, 0, bitmap.getWidth(), bitmap.getHeight(), matrix, true);

    // Recycle the old bitmap if it has changed.
    if (rotatedBitmap != bitmap) {
      bitmap.recycle();
    }
    return rotatedBitmap;
  }

The full code can be seen by clicking on the link: https://github.com/googlesamples/mlkit/blob/master/android/vision-quickstart/app/src/main/java/com/google/mlkit/vision/demo/BitmapUtils.java

I have to convert com.google.mlkit.vision.common.InputImage to equivalent Bitmap image in android using Java. Right now I am using the following code.

// iImage is an object of InputImage
Bitmap bmap = Bitmap.createBitmap(iImage.getWidth(), iImage.getHeight(), Bitmap.Config.RGB_565);
bmap.copyPixelsFromBuffer(iImage.getByteBuffer());

The above code is NOT converting the InputImage to Bitmap. Can anyone please suggest me the efficient way of converting InputImage to Bitmap.