i have no idea where to ask for ffmpeg help :( guess I'll try here

I created a silent file with ffmpeg -f lavfi -i anullsrc=channel_layout=stereo:sample_rate=44100 -t 7 silence.flac

then I tried to put it in between two files by making concat.txt

file 'a.flac'
file 'silence.flac'
file 'b.flac'

and doing ffmpeg -f concat -i input.txt output.flac

however ffmpeg doesn't like that and freaks out with a lot of blocksize 4608 > 4096 decode_frame() failed. it concatenates the two files but not my silence

how do I create a silent file with ffmpeg that has a normal blocksize/will work? (keep in mind that when I looked up 'flac blocksize' the only documentation I could find pointed directly to the ffmpeg source code and I'm not reading that lol)

@genevieve are you trying to do it without resampling / re-encoding ?

Honestly in my experience ffmpeg just does this sometimes. I use it quite a bit and I've never found any real solutions to these bugs / issues. I've had errors like this when concatting videos and also when trying to compress a single video.

I don't like it but the only solution I've found that works involves resampling. Sometimes if I convert the videos(s) or resample them, I can get it to work. If they are really high quality to start you might not notice the difference from it being re-encoded an extra time

@forestjohnson no I don't mind re-encoding in this case! (just did it with zrhythm, which was overkill but worked lol)

I actually didn't know the way I was doing it was avoiding re-encoding, would you mind telling me why that's the case?

and yeah i relate to the rest of your thread haha, even if i'm still a complete noob with ffmpeg

Follow

@genevieve I don't know the details and could be wrong in the case of flac audio but for a lot of formats, ffmpeg is able to concatenate / trim / cut the media without re encoding it, that's a large part of what makes it so special I think. It tries to do that by default unless you tell it to do something that requires re encoding

@genevieve

> "How do you maintain audiovisual materials? Proper care. First, wash and dry your hands thoruffly. Then, use ffmpeg."

video.strongthany.cc/watch?v=9 😂

Sign in to participate in the conversation
Pixietown

Small server part of the pixie.town infrastructure. Registration is closed.