[FFmpeg-user] 回复： How to control the bitrate between a min and maxin VBR encoding

[韩瑞松]

Thank you for answer first.


Now I use command below:
    ffmpeg -y -i input.mp4 -analyzeduration 2G -pass 1 -vcodec libx264 -vpre fastfirstpass -b 1024k -s 1056x576 -aspect 1056:576 -r 25 -psnr -an -f flv -map_chapters -1:-1 -g 50 /dev/null
    ffmpeg -y -i input.mp4 -analyzeduration 2G -pass 2 -vcodec libx264 -vpre normal -b 1024k -s 1056x576 -aspect 1056:576 -r 25 -psnr -acodec copy -f flv -map_chapters -1:-1 -g 50 output.flv


The output.flv is a video with VBR,The part of maxbitrate is bigger than 1024k ,I want to control the bitrate between 1500k because of my poor boundwidth.


I searchd more on google .There are some options can be used.Such as -minrate -maxrate -bufsize.
I used them,but the quality of the output is not satisfactory.


Someone said that this command only effective in CBR mode.


Is there any other options can make me control the bitrate?








------------------ 原始邮件 ------------------
发件人: "Carl Eugen Hoyos"<cehoyos at ag.or.at>;
发送时间: 2013年4月2日(星期二) 中午1:37
收件人: "ffmpeg-user"<ffmpeg-user at ffmpeg.org>; 

主题: Re: [FFmpeg-user] How to control the bitrate between a min and maxin VBR encoding



韩瑞松 <550399108 <at> qq.com> writes:

> How can I make the bitrate under control?

-vb allows to control the bitrate.

> Which version of ffmpeg can be useful?

On this mailing list, only current git head is supported.

Carl Eugen

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