avio_wb32(pb, 0); ///< mPrimingFrames
avio_wb32(pb, 0); ///< mRemainderFrames
avio_write(pb, caf->pkt_sizes, caf->size_entries_used);
avio_wb32(pb, 0); ///< mPrimingFrames
avio_wb32(pb, 0); ///< mRemainderFrames
avio_write(pb, caf->pkt_sizes, caf->size_entries_used);