select: new filter to drop frames based on offset and skip

Motivation was to select only odd or even frames.

gst/select/CMakeLists.txt

@@ -0,0 +1,28 @@
+set (SOURCES
+  gstselect.c
+  )
+    
+set (HEADERS
+  gstselect.h)
+    
+include_directories (AFTER
+  ${ORC_INCLUDE_DIR})
+
+set (libname libgstselect)
+
+add_library (${libname} MODULE
+  ${SOURCES}
+  ${HEADERS})
+  
+target_link_libraries (${libname}
+  ${ORC_LIBRARIES}
+  ${GLIB2_LIBRARIES}
+  ${GOBJECT_LIBRARIES}
+  ${GSTREAMER_LIBRARY}
+  ${GSTREAMER_BASE_LIBRARY}
+  ${GSTREAMER_VIDEO_LIBRARY})
+  
+set (pdbfile "${CMAKE_CURRENT_BINARY_DIR}/\${CMAKE_INSTALL_CONFIG_NAME}/${libname}.pdb")
+install (FILES ${pdbfile} DESTINATION lib/gstreamer-1.0 COMPONENT pdb)
+install(TARGETS ${libname}
+  LIBRARY DESTINATION lib/gstreamer-1.0)