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diff --git a/doc/filters.texi b/doc/filters.texi index 61307e5838..b17b115288 100644 --- a/doc/filters.texi +++ b/doc/filters.texi @@ -10618,6 +10618,43 @@ less than @code{0}, the filter will try to use a good random seed on a best effort basis. @end table +@section readvitc + +Read vertical interval timecode (VITC) information from the top lines of a +video frame. + +The filter adds frame metadata key @code{lavfi.readvitc.tc_str} with the +timecode value, if a valid timecode has been detected. Further metadata key +@code{lavfi.readvitc.found} is set to 0/1 depending on whether +timecode data has been found or not. + +This filter accepts the following options: + +@table @option +@item scan_max +Set the maximum number of lines to scan for VITC data. If the value is set to +@code{-1} the full video frame is scanned. Default is @code{45}. + +@item thr_b +Set the luma threshold for black. Accepts float numbers in the range [0.0,1.0], +default value is @code{0.2}. The value must be equal or less than @code{thr_w}. + +@item thr_w +Set the luma threshold for white. Accepts float numbers in the range [0.0,1.0], +default value is @code{0.6}. The value must be equal or greater than @code{thr_b}. +@end table + +@subsection Examples + +@itemize +@item +Detect and draw VITC data onto the video frame; if no valid VITC is detected, +draw @code{--:--:--:--} as a placeholder: +@example +ffmpeg -i input.avi -filter:v 'readvitc,drawtext=fontfile=FreeMono.ttf:text=%@{metadata\\:lavfi.readvitc.tc_str\\:--\\\\\\:--\\\\\\:--\\\\\\:--@}:x=(w-tw)/2:y=400-ascent' +@end example +@end itemize + @section remap Remap pixels using 2nd: Xmap and 3rd: Ymap input video stream. |