<p><code>29.97</code> is shorthand for 30000/1001. There is no <code>29.970000...</code> frame rate standard. FFmpeg will keep the native framerate (usually), so no need to specify an output <code>-r</code> value.</p>

CC BY-SA 3.0
2017-05-31T07:20:04.357Z
Thanks! So I can understand that the Sony Pro camera, in fact, shot at 30000/1001 fps.
shintaroid
CC BY-SA 3.0
2017-05-31T05:15:03.953Z
2017-05-31T05:15:03.953Z
Gyan
<p>According to this <a href="https://ffmpeg.org/ffmpeg-utils.html#Video-rate" rel="nofollow noreferrer">ffmpeg documentation</a>, it seems one of the 'native' frame rate for <code>ffmpeg</code> is</p>

<blockquote>
  <p>'ntsc':   30000/1001</p>
</blockquote>

<p>while 30000/1001=29.9700... does not equal to 29.97, I wonder if a Sony Pro camera really means it shots in 29.97, not 30000/1001?</p>

<p>If that Sony camera does shot in exact 29.97fps, I suppose we should keep the 29.97fps, should not change the fps of the video file to 30000/1001?</p>

<ffmpeg><framerate>
A Sony Pro camera's spec shows it shots in 29.97fps, does it really mean it?
shintaroid
# A Sony Pro camera's spec shows it shots in 29.97fps, does it really mean it?

(Asked by: username_0 on 2017-05-31)

According to this [ffmpeg documentation](https://ffmpeg.org/ffmpeg-utils.html#Video-rate), it seems one of the 'native' frame rate for `ffmpeg` is

> 'ntsc': 30000/1001

while 30000/1001=29.9700... does not equal to 29.97, I wonder if a Sony Pro camera really means it shots in 29.97, not 30000/1001?

If that Sony camera does shot in exact 29.97fps, I suppose we should keep the 29.97fps, should not change the fps of the video file to 30000/1001?

**Tags:** ffmpeg, framerate


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## 1 answers

### Answer by username_1 on 2017-05-31. Score: 3 | Accepted answer

`29.97` is shorthand for 30000/1001. There is no `29.970000...` frame rate standard. FFmpeg will keep the native framerate (usually), so no need to specify an output `-r` value.

> **Comments:**
> **username_0**: Thanks! So I can understand that the Sony Pro camera, in fact, shot at 30000/1001 fps.  

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