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author | Paul B Mahol <onemda@gmail.com> | 2017-01-14 19:04:54 +0100 |
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committer | Paul B Mahol <onemda@gmail.com> | 2017-01-24 10:20:10 +0100 |
commit | 08e5732318a46fd1fe9a406ff829838483dc1358 (patch) | |
tree | 3e80cdb6ee646ce924e9ee3a71cdc82328cbd5b5 /doc | |
parent | 1bb192ef6c1771ee18d1c5ed31d7c0cac8a25ebb (diff) | |
download | ffmpeg-streaming-08e5732318a46fd1fe9a406ff829838483dc1358.zip ffmpeg-streaming-08e5732318a46fd1fe9a406ff829838483dc1358.tar.gz |
avfilter: add EIA-608 line extractor
Signed-off-by: Dave Rice <dave@dericed.com>
Signed-off-by: Paul B Mahol <onemda@gmail.com>
Diffstat (limited to 'doc')
-rw-r--r-- | doc/filters.texi | 70 |
1 files changed, 70 insertions, 0 deletions
diff --git a/doc/filters.texi b/doc/filters.texi index a0c2980..ec9563e 100644 --- a/doc/filters.texi +++ b/doc/filters.texi @@ -11253,6 +11253,76 @@ less than @code{0}, the filter will try to use a good random seed on a best effort basis. @end table +@section readeia608 + +Read closed captioning (EIA-608) information from the top lines of a video frame. + +This filter adds frame metadata for @code{lavfi.readeia608.X.cc} and +@code{lavfi.readeia608.X.line}, where @code{X} is the number of the identified line +with EIA-608 data (starting from 0). A description of each metadata value follows: + +@table @option +@item lavfi.readeia608.X.cc +The two bytes stored as EIA-608 data (printed in hexadecimal). + +@item lavfi.readeia608.X.line +The number of the line on which the EIA-608 data was identified and read. +@end table + +This filter accepts the following options: + +@table @option +@item scan_min +Set the line to start scanning for EIA-608 data. Default is @code{0}. + +@item scan_max +Set the line to end scanning for EIA-608 data. Default is @code{29}. + +@item mac +Set minimal acceptable amplitude change for sync codes detection. +Default is @code{0.2}. Allowed range is @code{[0.001 - 1]}. + +@item spw +Set the ratio of width reserved for sync code detection. +Default is @code{0.27}. Allowed range is @code{[0.01 - 0.7]}. + +@item mhd +Set the max peaks height difference for sync code detection. +Default is @code{0.1}. Allowed range is @code{[0.0 - 0.5]}. + +@item mpd +Set max peaks period difference for sync code detection. +Default is @code{0.1}. Allowed range is @code{[0.0 - 0.5]}. + +@item msd +Set the first two max start code bits differences. +Default is @code{0.02}. Allowed range is @code{[0.0 - 0.5]}. + +@item bhd +Set the minimum ratio of bits height compared to 3rd start code bit. +Default is @code{0.75}. Allowed range is @code{[0.01 - 1]}. + +@item th_w +Set the white color threshold. Default is @code{0.35}. Allowed range is @code{[0.1 - 1]}. + +@item th_b +Set the black color threshold. Default is @code{0.15}. Allowed range is @code{[0.0 - 0.5]}. + +@item chp +Enable checking the parity bit. In the event of a parity error, the filter will output +@code{0x00} for that character. Default is false. +@end table + +@subsection Examples + +@itemize +@item +Output a csv with presentation time and the first two lines of identified EIA-608 captioning data. +@example +ffprobe -f lavfi -i movie=captioned_video.mov,readeia608 -show_entries frame=pkt_pts_time:frame_tags=lavfi.readeia608.0.cc,lavfi.readeia608.1.cc -of csv +@end example +@end itemize + @section readvitc Read vertical interval timecode (VITC) information from the top lines of a |