Add a new function to calculate video stream framerate which rely on SPS, slice header and pic timing using formula: time_scale 1 1 fps = ----------------- x --------------- x ------------------------ num_units_in_tick DeltaTfiDivisor (field_pic_flag ? 2 : 1) See section E2.1 of H264 specification for definition of variables. https://bugzilla.gnome.org/show_bug.cgi?id=723352