Question about using ffmpeg to convert a sequence of images to video

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Question about using ffmpeg to convert a sequence of images to video

陈阳
Hi guys,
       
     I use ffmpeg to convert a sequence of images to a video, i find that after i feed first image to it and almost 6 seconds later ffmpeg output first video frame to me.
I use command as follow:
ffmpeg -f image2pipe -r 100 -i pipe:0 -f flv -r 100 -tune zerolatency -preset ultrafast -bufsize 2M -codec:v libx264 -codec:a libmp3lame -bf 0 -muxdelay 0.001 -s 478x850 -b:v 2M pipe:1
     Is my options is right?
    Or others led to this result?
    How can i get first video frame quickly once i feed the first frame?
    By the way, i create a question in stack overflow, maybe you could answer my question at here(https://stackoverflow.com/q/49646564/8782964)
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Re: Question about using ffmpeg to convert a sequence of images to video

Victor Carneiro Fardim
Hi, Chen Yang.

I see you are using good encoder settings to minimize encoding latency.

In this case, I'd try messing around with the VBV buffer (`-bufsize`). Try setting `-bufsize` very low, for instance, 128k. This will, however, result in a (significantly) reduced quality due to the bitrate not being able to fluctuate too much to compensate for changes in image complexity - essentially resulting in a mostly constant bitrate. You can play around with the

If you are streaming live video, you may also want to lower the GOP length, to reduce the initial buffering delay. Note that this will also greatly affect quality, so use it with care.

You may also try other container formats, since muxing also introduces varying degrees of latency.

Good encodes,

Victor Carneiro
-------- Mensagem Original --------
Ativo 4 de abr de 2018 06:00, 陈阳 escreveu:

> Hi guys,
>
> I use ffmpeg to convert a sequence of images to a video, i find that after i feed first image to it and almost 6 seconds later ffmpeg output first video frame to me.
> I use command as follow:
> ffmpeg -f image2pipe -r 100 -i pipe:0 -f flv -r 100 -tune zerolatency -preset ultrafast -bufsize 2M -codec:v libx264 -codec:a libmp3lame -bf 0 -muxdelay 0.001 -s 478x850 -b:v 2M pipe:1
> Is my options is right?
> Or others led to this result?
> How can i get first video frame quickly once i feed the first frame?
> By the way, i create a question in stack overflow, maybe you could answer my question at here(https://stackoverflow.com/q/49646564/8782964)
> _______________________________________________
> ffmpeg-user mailing list
> [hidden email]
> http://ffmpeg.org/mailman/listinfo/ffmpeg-user
>
> To unsubscribe, visit link above, or email
> [hidden email] with subject "unsubscribe".
_______________________________________________
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[hidden email]
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[hidden email] with subject "unsubscribe".