Hi, Does cv_bridge support converting ROI image to ROS msg? I'm trying to publish ROI cropped image as followings, however the hoge.ppm and published image message are differ. hoge.ppm start from (width/2 height/2) of the original image but published image starts from (0 0).Both image size are width/2 and height/2. IplImage *frame = ....; int width = frame->width, height = frame->height; cvSetImageROI(frame, cvRect(width/2, height/2, width/2, height/2)); cvSaveImage("hoge.ppm", frame); pub_narrow_.publish(bridge.cvToImgMsg(frame, "bgr8")); == Kei Okada