<p>I'm using ffmpeg to transcode mp4 file, I got the below command from: <a href="http://www.wowza.com/forums/content.php?192-Encoding-Suggestions-for-Video-on-Demand" rel="nofollow">http://www.wowza.com/forums/content.php?192-Encoding-Suggestions-for-Video-on-Demand</a>.</p>

<pre><code>ffmpeg -y -i Butterfly_HD_1080p.mp4 -s 320x180 -y -strict experimental -acodec aac -ab 64k -ac 2 -ar 48000 -vcodec libx264 -vprofile main -g 48 -b 270000 -threads 64 butterfly_400.mp4
</code></pre>

<p>based on what they decide the bitrate for above output file will be 400(400000)? what the equation that they use for bitrate value?</p>

CC BY-SA 3.0
2015-08-15T17:22:18.897Z
I don't understand your question. Also, that command from the link you provided is not good. If you explain what you're trying to do we can provide a sane command.
llogan
CC BY-SA 3.0
2015-08-15T19:15:53.613Z
Based on the command that you copied from the forum post, the bit rate of the video encoding would be 270,000 bits/second. The bitrate of the AAC audio encoding would be 64,000 bits/second (hence `-ab 64k`), so the total bitrate for the assembled file would be 270k+64k=334k.

So I have no idea where you're getting 400(400000) from, and I would have to agree with Neckbeard: telling us what you want to accomplish makes it possible to provide answers.
WineSoaked
CC BY-SA 3.0
2015-08-16T04:17:11.307Z
I need to encode videos and add them to wowza server. after encoding I need to create smil file for these videos and bitrate is required filed on smil file., so, what is the bitrate for the above command? is it 270000? . but in wowza documentation they fill smil file with 400000 bitrate for the same command.
jobin
CC BY-SA 3.0
2015-08-16T04:17:51.283Z
@LordNeckbeard can share with me good commands? I need to use them with mpeg dash
jobin
<ffmpeg>
What the equation that we should use to know the bitrate value?
jobin
# What the equation that we should use to know the bitrate value?

(Asked by: username_0 on 2015-08-15)

I'm using ffmpeg to transcode mp4 file, I got the below command from: http://www.wowza.com/forums/content.php?192-Encoding-Suggestions-for-Video-on-Demand.
ffmpeg -y -i Butterfly_HD_1080p.mp4 -s 320x180 -y -strict experimental -acodec aac -ab 64k -ac 2 -ar 48000 -vcodec libx264 -vprofile main -g 48 -b 270000 -threads 64 butterfly_400.mp4

based on what they decide the bitrate for above output file will be 400(400000)? what the equation that they use for bitrate value?

**Tags:** ffmpeg

> **Comments:**
> **username_1**: I don't understand your question. Also, that command from the link you provided is not good. If you explain what you're trying to do we can provide a sane command.  
> **username_2**: Based on the command that you copied from the forum post, the bit rate of the video encoding would be 270,000 bits/second. The bitrate of the AAC audio encoding would be 64,000 bits/second (hence `-ab 64k`), so the total bitrate for the assembled file would be 270k+64k=334k.  So I have no idea where you're getting 400(400000) from, and I would have to agree with Neckbeard: telling us what you want to accomplish makes it possible to provide answers.  
> **username_0**: I need to encode videos and add them to wowza server. after encoding I need to create smil file for these videos and bitrate is required filed on smil file., so, what is the bitrate for the above command? is it 270000? . but in wowza documentation they fill smil file with 400000 bitrate for the same command.  
> **username_0**: @LordNeckbeard can share with me good commands? I need to use them with mpeg dash  

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## 0 answers

