[FFmpeg-user] Segment Metadata

[Jeremy Whitaker]

Hello, I was wondering if it is at all possible to change the metadata of
video segments in ffmpeg as the segments are being created. I know that by
using the "-metadata" tag, you can change the metadata of the -i input
video, but if that -i input video is being split into different segments by
the "-f segment" option, then how do you change the metadata of the
resulting segments while the -i input video is being segmented? I know that
it's possible to change the metadata after the segmenting has completed,
but this isn't that useful since I'm looking to stream the segments live as
the input video is being segmented. To give a little better description:

ffmpeg -f video4linux2 -s wvga -t ${CAPTURE_DURATION} -i "/dev/video0" -r 30 \
-vcodec ${VID_CODEC} -s:v 640x480 -b:v 80k -keyint_min 30 -g 30 \
-sc_threshold 0 -map 0 -flags -global_header -qcomp 0.8 \
-qmin 10 -qmax 51 -qdiff 4 -f segment -segment_time ${SEG_TIME} \
-segment_format ${SEG_FORMAT} -metadata START=0 -y
"${LOCATE}${OUTPUT}%01d.${EXTENSION}"

Essentially what I'm doing is taking a video from the standard video
input and segmenting it. Once the video segments are created, I can
test videos by throwing them all into a VLC playlist, and when the
segment format is "mp4", there is a notable delay between each video
segment where VLC won't start the video segment until it has played
back the time again where the segment was in the original video. So
for example, if I have a 30 second video, and split it into 5 second
segments, VLC will play the 1st segment immediately, but it will wait
5 seconds before playing the 2nd segment after the 1st segment has
finished playing. It does this because the 2nd segment has a start
time metadata of 5 seconds, so VLC thinks that it has to wait 5
seconds before playing the 2nd segment. What I'm wondering is if
there's a way to tell ffmpeg to set the segment start time metadata to
0 seconds as the segments are being created. Any help would be greatly
appreciated.