diff --git a/aruco_pose/src/aruco_map.cpp b/aruco_pose/src/aruco_map.cpp
index 796cf3e5..fb48ee05 100644
--- a/aruco_pose/src/aruco_map.cpp
+++ b/aruco_pose/src/aruco_map.cpp
@@ -399,12 +399,19 @@ publish_debug:
 
 	void publishMapImage()
 	{
+		cv::Size size(image_width_, image_height_);
 		cv::Mat image;
 		cv_bridge::CvImage msg;
-		drawPlanarBoard(board_, cv::Size(image_width_, image_height_), image, image_margin_, 1);
 
-		cv::cvtColor(image, image, CV_GRAY2BGR);
-		msg.encoding = sensor_msgs::image_encodings::BGR8;
+		if (!board_->ids.empty()) {
+			_drawPlanarBoard(board_, size, image, image_margin_, 1);
+		} else {
+			// empty map
+			image.create(size, CV_8UC1);
+			image.setTo(cv::Scalar::all(255));
+		}
+
+		msg.encoding = sensor_msgs::image_encodings::MONO8;
 		msg.image = image;
 		img_pub_.publish(msg.toImageMsg());
 	}
diff --git a/aruco_pose/src/draw.cpp b/aruco_pose/src/draw.cpp
index 7bd593d4..da992c30 100644
--- a/aruco_pose/src/draw.cpp
+++ b/aruco_pose/src/draw.cpp
@@ -6,7 +6,7 @@
 using namespace cv;
 using namespace cv::aruco;
 
-void drawPlanarBoard(Board *_board, Size outSize, OutputArray _img, int marginSize,
+void _drawPlanarBoard(Board *_board, Size outSize, OutputArray _img, int marginSize,
                      int borderBits) {
 
     CV_Assert(outSize.area() > 0);
diff --git a/aruco_pose/src/draw.h b/aruco_pose/src/draw.h
index ce9d41d4..18ce1cc6 100644
--- a/aruco_pose/src/draw.h
+++ b/aruco_pose/src/draw.h
@@ -3,4 +3,4 @@
 #include <opencv2/opencv.hpp>
 #include <opencv2/aruco.hpp>
 
-void drawPlanarBoard(cv::aruco::Board *_board, cv::Size outSize, cv::OutputArray _img, int marginSize, int borderBits);
+void _drawPlanarBoard(cv::aruco::Board *_board, cv::Size outSize, cv::OutputArray _img, int marginSize, int borderBits);