<p>I met this anon on 4chan who made me notice a color issue in my webms. I generally make webm using ffmpeg and I never noticed a change in colors. He suggested me to change the color matrix into 601 but I have no idea of the criteria he used in the first place.</p>

<p><a href="https://i.sstatic.net/LuERk.jpg" rel="nofollow noreferrer"><img src="https://i.sstatic.net/LuERk.jpg" alt="enter image description here"></a></p>

<p>Why there is this difference in colors from source (mkv) and output (webm)? What's the best way to preserve the color scheme during conversion/compression? This is the typical command I use when I convert from mkv to webm:</p>

<pre><code>ffmpeg -threads 4 -i &lt;input&gt; -c:v libvpx -b:v 1500K -vf scale=-1:360 -an -map 0:v:0 &lt;output&gt;
</code></pre>

<p>What is wrong? I'm going to post more info about the source in 30 minutes, if you need it.</p>

CC BY-SA 3.0
2017-09-01T20:00:21.303Z
Show the console output of the command,
Gyan
CC BY-SA 3.0
2017-09-02T00:19:25.040Z
here is the relevant part https://pastebin.com/if9eNSkV
1500822802299
CC BY-SA 3.0
2017-09-02T17:39:12.343Z
Basic filter would be `colormatrix=bt709:bt601` This goes before the scale. But without knowing all source properties and intended target, this is a crude guess.
Gyan
<ffmpeg>
FFMPEG, colormatrix and WEBM conversion
1500822802299
# FFMPEG, colormatrix and WEBM conversion

(Asked by: username_0 on 2017-09-01)

I met this anon on 4chan who made me notice a color issue in my webms. I generally make webm using ffmpeg and I never noticed a change in colors. He suggested me to change the color matrix into 601 but I have no idea of the criteria he used in the first place.

Why there is this difference in colors from source (mkv) and output (webm)? What's the best way to preserve the color scheme during conversion/compression? This is the typical command I use when I convert from mkv to webm:
ffmpeg -threads 4 -i  -c:v libvpx -b:v 1500K -vf scale=-1:360 -an -map 0:v:0 

What is wrong? I'm going to post more info about the source in 30 minutes, if you need it.

**Tags:** ffmpeg

> **Comments:**
> **username_1**: Show the console output of the command,  
> **username_0**: here is the relevant part https://pastebin.com/if9eNSkV  
> **username_1**: Basic filter would be `colormatrix=bt709:bt601` This goes before the scale. But without knowing all source properties and intended target, this is a crude guess.  

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## 0 answers

