diff --git a/src/mynteye/api/processor/disparity_processor.cc b/src/mynteye/api/processor/disparity_processor.cc
index 7816789..b2e86e2 100644
--- a/src/mynteye/api/processor/disparity_processor.cc
+++ b/src/mynteye/api/processor/disparity_processor.cc
@@ -46,7 +46,7 @@ DisparityProcessor::DisparityProcessor(DisparityComputingMethod type,
             100,                             // speckleWindowSize
             32,                              // speckleRange
             false));                         // fullDP
-    LOG(ERROR) << "not supported in opencv 2.x";
+    LOG(ERROR) << "BM not supported in opencv 2.x, use sgbm";
     // int bmWinSize = 3;
     // // StereoBM
     // //   https://docs.opencv.org/2.4/modules/calib3d/doc/camera_calibration_and_3d_reconstruction.html#stereobm-stereobm
@@ -130,7 +130,8 @@ bool DisparityProcessor::OnProcess(
   if (type_ == DisparityComputingMethod::SGBM) {
     (*sgbm_matcher)(input->first, input->second, disparity);
   } else if (type_ == DisparityComputingMethod::BM) {
-    LOG(ERROR) << "not supported in opencv 2.x";
+    // LOG(ERROR) << "not supported in opencv 2.x";
+    (*sgbm_matcher)(input->first, input->second, disparity);
     // cv::Mat tmp1, tmp2;
     // cv::cvtColor(input->first, tmp1, CV_RGB2GRAY);
     // cv::cvtColor(input->second, tmp2, CV_RGB2GRAY);
diff --git a/wrappers/ros/src/mynt_eye_ros_wrapper/launch/mynteye.launch b/wrappers/ros/src/mynt_eye_ros_wrapper/launch/mynteye.launch
index 8a571db..4eae1e0 100644
--- a/wrappers/ros/src/mynt_eye_ros_wrapper/launch/mynteye.launch
+++ b/wrappers/ros/src/mynt_eye_ros_wrapper/launch/mynteye.launch
@@ -59,7 +59,7 @@
   <!-- disparity computing method type -->
   <arg name="sgbm"   default="0" />
   <arg name="bm"   default="1" />
-  <arg name="disparity_computing_method"   default="$(arg bm)" />
+  <arg name="disparity_computing_method"   default="$(arg sgbm)" />
 
   <arg name="enable_left_rect" default="false" />
   <arg name="enable_right_rect" default="false" />