gboolean (*transform_size) (GstBaseTransform *trans,
GstPadDirection direction,
GstCaps *caps, gsize size,
GstCaps *othercaps, gsize *othersize);
gboolean (*transform_size) (GstBaseTransform *trans,
GstPadDirection direction,
GstCaps *caps, gsize size,
GstCaps *othercaps, gsize *othersize);