<p>From <a href="http://x264.nl/x264/10bit_02-ateme-why_does_10bit_save_bandwidth.pdf" rel="nofollow noreferrer">Why does 10-bit save bandwidth (even when content is 8-bit)?</a> (<a href="https://yukisubs.wordpress.com/wp-content/uploads/2016/10/why_does_10bit_save_bandwidth_-_ateme.pdf" rel="nofollow noreferrer">alt. URL</a>)</p>
<blockquote>
<p><strong>So why does a AVC/H.264 10-bit encoder perform better than 8-bit?</strong><br />
When encoding with the 10-bit tool, the compression process is
performed with at least 10-bit accuracy compared to only 8-bit
otherwise. So there is less truncation errors, especially in the
motion compensation stage, increasing the efficiency of compression
tools. As a consequence, there is less need to quantize to achieve a
given bit-rate. The net result is a better quality for the same
bit-rate or conversely less bit-rate for the same quality: between 5%
and 20% on typical sources.</p>
</blockquote>
<p>See the link for more information.</p>

CC BY-SA 4.0
2012-12-03T20:25:32.140Z
2024-11-19T19:24:41.993Z
2024-11-19T19:24:41.993Z
llogan
<p>I'll start off by saying that I know next to nothing about video encoding and I'm looking for a nice tutorial explaining the basics (I have a technical background and some knowledge of signal processing) </p>

<p>I've heard that encoding a video with 8-bit color can actually take more filesize than in 10-bit color. The explanation offered was that since the source file was in 10-bit color, it's somehow easier to stay in 10-bit color. I don't understand how that's possible, because whatever algorithm is used to convert between video formats can do what it needs to do, and when the time comes to convert to 8-bit quality, just round off the color. I don't see how rounding off a color could contribute to file size. </p>

CC BY-SA 3.0
2012-12-02T11:31:13.663Z
That's surely just not true in general, but it might hold for certain codecs. You'll need to be a bit more specific.
leftaroundabout
<file-formats><encoding>
How could an 8-bit encoding take more memory than a 10-bit encoding?
Satoru
# How could an 8-bit encoding take more memory than a 10-bit encoding?

(Asked by: username_0 on 2012-12-02)

I'll start off by saying that I know next to nothing about video encoding and I'm looking for a nice tutorial explaining the basics (I have a technical background and some knowledge of signal processing)

I've heard that encoding a video with 8-bit color can actually take more filesize than in 10-bit color. The explanation offered was that since the source file was in 10-bit color, it's somehow easier to stay in 10-bit color. I don't understand how that's possible, because whatever algorithm is used to convert between video formats can do what it needs to do, and when the time comes to convert to 8-bit quality, just round off the color. I don't see how rounding off a color could contribute to file size.

**Tags:** file-formats, encoding

> **Comments:**
> **username_1**: That's surely just not true in general, but it might hold for certain codecs. You'll need to be a bit more specific.  

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## 1 answers

### Answer by username_2 on 2012-12-03. Score: 2

From [Why does 10-bit save bandwidth (even when content is 8-bit)?](http://x264.nl/x264/10bit_02-ateme-why_does_10bit_save_bandwidth.pdf) ([alt. URL](https://yukisubs.wordpress.com/wp-content/uploads/2016/10/why_does_10bit_save_bandwidth_-_ateme.pdf))

> **So why does a AVC/H.264 10-bit encoder perform better than 8-bit?**  
> When encoding with the 10-bit tool, the compression process is
> performed with at least 10-bit accuracy compared to only 8-bit
> otherwise. So there is less truncation errors, especially in the
> motion compensation stage, increasing the efficiency of compression
> tools. As a consequence, there is less need to quantize to achieve a
> given bit-rate. The net result is a better quality for the same
> bit-rate or conversely less bit-rate for the same quality: between 5%
> and 20% on typical sources.

See the link for more information.


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