unsigned long ffio_get_checksum(AVIOContext *s);
unsigned long ff_crc04C11DB7_update(unsigned long checksum, const uint8_t *buf,
unsigned int len);
unsigned long ffio_get_checksum(AVIOContext *s);
unsigned long ff_crc04C11DB7_update(unsigned long checksum, const uint8_t *buf,
unsigned int len);