Read closed captioning (EIA-608) information from the top lines of a video frame.
This filter adds frame metadata for lavfi.readeia608.X.cc and
lavfi.readeia608.X.line, where X is the number of the identified line
with EIA-608 data (starting from 0). A description of each metadata value follows:
- lavfi.readeia608.X.cc
-
The two bytes stored as EIA-608 data (printed in hexadecimal).
- lavfi.readeia608.X.line
-
The number of the line on which the EIA-608 data was identified and read.
This filter accepts the following options:
- scan_min
-
Set the line to start scanning for EIA-608 data. Default is
0. - scan_max
-
Set the line to end scanning for EIA-608 data. Default is
29. - spw
-
Set the ratio of width reserved for sync code detection. Default is
0.27. Allowed range is[0.1 - 0.7]. - chp
-
Enable checking the parity bit. In the event of a parity error, the filter will output
0x00for that character. Default is false. - lp
-
Lowpass lines prior to further processing. Default is enabled.
Commands
This filter supports the all above options as commands.
Examples
-
Output a csv with presentation time and the first two lines of identified EIA-608 captioning data.
ffprobe -f lavfi -i movie=captioned_video.mov,readeia608 -show_entries frame=pts_time:frame_tags=lavfi.readeia608.0.cc,lavfi.readeia608.1.cc -of csv