Am 17.03.2021 um 19:31 schrieb Steven Kan:
On Mar 6, 2021, at 11:22 AM, Steven Kan <ste...@kan.org> wrote:
On Mar 5, 2021, at 2:00 PM, Michael Koch <astroelectro...@t-online.de> wrote:
Am 05.03.2021 um 20:33 schrieb Steven Kan:
I’d like to assemble these videos, side-by-side, but synced in time, which
means the TrailDown video needs to start 50 seconds after the TrailUp
video.
try this command line:
ffmpeg -i input1.mp4 -i input2.mp4 -filter_complex
"[0]tpad=start_duration=50[a];[a][1]hstack” out.mp4
Thank you! That worked perfectly, and now that I understand the syntax, this
works as well (to pad the end of the second track by 15 sec:
ffmpeg -i Input1.mp4 -i Input2 -filter_complex
"[0]tpad=start_duration=50[a];[1]tpad=stop_duration=15[b];[a][b]hstack” Out.mp4
More on this!
tpad=start_duration works to delay the start of one video, but now I need to
fix the audio sync. For example this command:
ffmpeg -i TrailDown.mp4 -i TrailUp.mp4 -filter_complex
"[0]tpad=start_duration=2.5[a];[a][1]hstack" -vcodec libx264 Coyote2Up.mp4
results in this video:
https://www.youtube.com/watch?v=_PDPONEU3YA#t=35s
Only the left half (TrailDown) camera has a microphone, and it’s apparent that
the audio sync is off by the same 2.5 seconds that I’ve delayed its video. You
can hear the female coyote (with the stumpy tail) scratching the ground 2.5
seconds before she actually does it.
What flag should I add to also delay its audio? Thanks!
Add the "adelay" filter to the filter chain:
adelay=2500
Michael
_______________________________________________
ffmpeg-user mailing list
ffmpeg-user@ffmpeg.org
https://ffmpeg.org/mailman/listinfo/ffmpeg-user
To unsubscribe, visit link above, or email
ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".
