<p>Use</p>

<pre><code>-af "volume=enable='gte(t,30)*lt(mod(t,30),3)':volume=0"
</code></pre>

CC BY-SA 4.0
2018-06-02T15:43:19.287Z
Can you explain the parameters for me? Thank you so much
Monso
CC BY-SA 4.0
2018-06-02T16:12:47.773Z
`lt(mod(t,30),3)` selects first 3 seconds of every 30 seconds, `gte(t,30)` starts selection from  t=30s, so that the first 3 seconds (0-3) aren't selected.
Gyan
CC BY-SA 4.0
2018-06-02T12:32:33.773Z
2018-06-02T12:52:22.543Z
2018-06-02T12:52:22.543Z
Gyan
<p>I have the code below I want it to automatically increment up like this:<br>
<code>(t, 30,33)</code> and <code>(t, 60,63)</code>, <code>(t, 90,93)</code> and so on it adds <code>30</code> units.</p>

<pre><code>     ffmpeg -i in.mov -vcodec copy -af "volume=enable='between(t,30,33)':volume=0"out2.mov
</code></pre>

<ffmpeg>
Increase volume with ffmpeg
Monso
# Increase volume with ffmpeg

(Asked by: username_0 on 2018-06-02)

I have the code below I want it to automatically increment up like this:
(t, 30,33) and (t, 60,63), (t, 90,93) and so on it adds 30 units.
     ffmpeg -i in.mov -vcodec copy -af "volume=enable='between(t,30,33)':volume=0"out2.mov

**Tags:** ffmpeg


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## 1 answers

### Answer by username_1 on 2018-06-02. Score: 2 | Accepted answer

Use
-af "volume=enable='gte(t,30)*lt(mod(t,30),3)':volume=0"

> **Comments:**
> **username_0**: Can you explain the parameters for me? Thank you so much  
> **username_1**: `lt(mod(t,30),3)` selects first 3 seconds of every 30 seconds, `gte(t,30)` starts selection from  t=30s, so that the first 3 seconds (0-3) aren't selected.  

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