<p>According to the site you referred to:
<a href="http://www.encoding.com/what_are_the_best_flash_video_frame_dimensions" rel="nofollow">http://www.encoding.com/what_are_the_best_flash_video_frame_dimensions</a></p>

<p>The math behind the "Best, Better, and Good" video formats are based on if both Horizontal and Vertical pixels are divided by 16 for best, 8 for better, and 4 for good.</p>

<p>Therefore 256x144 is best, while 384x216 &amp; 128x72 are better, while 320x180 is good.</p>

CC BY-SA 3.0
2012-01-24T20:29:45.237Z
2012-01-24T21:12:05.190Z
2012-01-24T21:12:05.190Z
filzilla
<p>The resolutions you mentioned are standard in Video codec development are CIF [352x288] and QCIF [176x144] (some other formats here: <a href="http://dvrsecurityforum.com/showthread.php?tid=30" rel="nofollow">http://dvrsecurityforum.com/showthread.php?tid=30</a>) </p>

<p>The reason why all these formats recommend multiple of 16 - is because MPEG compression has Macroblocks which are sized 16x16. </p>

<p>CIF = 22 x 18 Macroblocks. and QCIF is essentially half of it both sides.</p>

CC BY-SA 3.0
2012-03-15T20:13:16.617Z
2012-03-15T20:13:16.617Z
Dipan Mehta
<p>I'm trying to setup my site to store uploaded user content in a 640x360 frame size, which will be presented back for viewing in that frame size and in a smaller frame size.</p>

<p>I'm trying to understand why this site (and others): <a href="http://www.encoding.com/what_are_the_best_flash_video_frame_dimensions" rel="nofollow">http://www.encoding.com/what_are_the_best_flash_video_frame_dimensions</a> recommend <strong>only</strong> the following values for smaller sizes:</p>

<pre><code>384 x 216
128 x 72
</code></pre>

<p>when clearly others like:</p>

<pre><code>320 x 180
256 x 144
</code></pre>

<p>also exist.</p>

<p>What is the mathematical reason behind recommending only these frame sizes?</p>

CC BY-SA 3.0
2011-12-21T08:15:17.953Z
Does this question belong elsewhere?
siliconpi
CC BY-SA 3.0
2012-03-15T20:08:00.457Z
This question seems more broadcast and compression specific than AV Production! Inviting experts to a new site proposal [Broadcast and Media Technologies](http://area51.stackexchange.com/proposals/36807/broadcast-and-media-technologies) which aims to capture more architectural and theoretical views around subjects like this. Join and invite others.
Dipan Mehta
<streaming><codec>
Scaling optimal video frame dimensions
siliconpi
# Scaling optimal video frame dimensions

(Asked by: username_0 on 2011-12-19)

I'm trying to setup my site to store uploaded user content in a 640x360 frame size, which will be presented back for viewing in that frame size and in a smaller frame size.
I'm trying to understand why this site (and others): http://www.encoding.com/what_are_the_best_flash_video_frame_dimensions recommend only the following values for smaller sizes:
384 x 216
128 x 72

when clearly others like:
320 x 180
256 x 144

also exist.
What is the mathematical reason behind recommending only these frame sizes?

**Tags:** streaming, codec

> **Comments:**
> **username_0**: Does this question belong elsewhere?  
> **username_1**: This question seems more broadcast and compression specific than AV Production! Inviting experts to a new site proposal [Broadcast and Media Technologies](http://area51.stackexchange.com/proposals/36807/broadcast-and-media-technologies) which aims to capture more architectural and theoretical views around subjects like this. Join and invite others.  

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## 2 answers

### Answer by username_2 on 2012-01-24. Score: 0 | Accepted answer

According to the site you referred to:
<http://www.encoding.com/what_are_the_best_flash_video_frame_dimensions>

The math behind the "Best, Better, and Good" video formats are based on if both Horizontal and Vertical pixels are divided by 16 for best, 8 for better, and 4 for good.

Therefore 256x144 is best, while 384x216 & 128x72 are better, while 320x180 is good.


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### Answer by username_1 on 2012-03-15. Score: 0

The resolutions you mentioned are standard in Video codec development are CIF [352x288] and QCIF [176x144] (some other formats here: <http://dvrsecurityforum.com/showthread.php?tid=30>)

The reason why all these formats recommend multiple of 16 - is because MPEG compression has Macroblocks which are sized 16x16.

CIF = 22 x 18 Macroblocks. and QCIF is essentially half of it both sides.


---

