added extra BUFFERSIZE doc and getter

modules/highgui/doc/reading_and_writing_images_and_video.rst

@@ -410,6 +410,8 @@ Returns the specified ``VideoCapture`` property
 
         * **CV_CAP_PROP_RECTIFICATION** Rectification flag for stereo cameras (note: only supported by DC1394 v 2.x backend currently)
 
+        * **CV_CAP_PROP_BUFFERSIZE** Amount of frames stored in internal buffer memory (note: only supported by DC1394 v 2.x backend currently)
+
 
 **Note**: When querying a property that is not supported by the backend used by the ``VideoCapture`` class, value 0 is returned.
 
@@ -465,6 +467,8 @@ Sets a property in the ``VideoCapture``.
 
         * **CV_CAP_PROP_RECTIFICATION** Rectification flag for stereo cameras (note: only supported by DC1394 v 2.x backend currently)
 
+        * **CV_CAP_PROP_BUFFERSIZE** Amount of frames stored in internal buffer memory (note: only supported by DC1394 v 2.x backend currently)
+
     :param value: Value of the property.
 
 

modules/highgui/src/cap_dc1394_v2.cpp

@@ -686,6 +686,8 @@ double CvCaptureCAM_DC1394_v2_CPP::getProperty(int propId)
         break;
     case CV_CAP_PROP_ISO_SPEED:
         return (double) isoSpeed;
+    case CV_CAP_PROP_BUFFERSIZE:
+        return (double) nDMABufs;
     default:
         if (propId<CV_CAP_PROP_MAX_DC1394 && dc1394properties[propId]!=-1
             && dcCam)