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Functions

void vbi_unref_page (vbi_page *pg)
int vbi_is_cached (vbi_decoder *, int pgno, int subno)
int vbi_cache_hi_subno (vbi_decoder *vbi, int pgno)
vbi_bool vbi_fetch_cc_page (vbi_decoder *vbi, vbi_page *pg, vbi_pgno pgno, vbi_bool reset)

Function Documentation

int vbi_is_cached ( vbi_decoder vbi,
int  pgno,
int  subno 
)
Parameters:
vbi 
pgno 
subno 
Deprecated:
At the moment pages can only be added to the cache but not removed unless the decoder is reset. That will change, making the result volatile in a multithreaded environment.
Returns:
TRUE if the given page is cached.
int vbi_cache_hi_subno ( vbi_decoder vbi,
int  pgno 
)
Parameters:
vbi 
pgno 
Deprecated:
Rationale same as vbi_is_cached().
Returns:
Highest cached subpage of this page.
vbi_bool vbi_fetch_cc_page ( vbi_decoder vbi,
vbi_page pg,
vbi_pgno  pgno,
vbi_bool  reset 
)
Parameters:
vbi Initialized vbi decoding context.
pg Place to store the formatted page.
pgno Page number 1 ... 8 of the page to fetch, see vbi_pgno.
reset TRUE resets the vbi_page dirty fields in cache after fetching. Pass FALSE only if you plan to call this function again to update other displays.

Fetches a Closed Caption page designated by pgno from the cache, formats and stores it in pg. CC pages are transmitted basically in two modes: at once and character by character ("roll-up" mode). Either way you get a snapshot of the page as it should appear on screen at present. With vbi_event_handler_add() you can request a VBI_EVENT_CAPTION event to be notified about pending changes (in case of "roll-up" mode that is with each new word received) and the vbi_page->dirty fields will mark the lines actually in need of updates, to speed up rendering.

Although safe to do, this function is not supposed to be called from an event handler, since rendering may block decoding for extended periods of time.

Returns:
FALSE if some error occured.
Generated on Mon Jul 5 13:28:44 2010 for ZVBI Library by  doxygen 1.6.3