Sets the integers pointed to by value_numerator and value_denominator
corresponding to the value of the given field. Caller is responsible
for making sure the field exists and has the correct type.
TRUE if the values could be set correctly. If there was no field with fieldname or the existing field did not contain a GstFraction, this function returns FALSE.
Sets the integers pointed to by value_numerator and value_denominator corresponding to the value of the given field. Caller is responsible for making sure the field exists and has the correct type.