<p>I believe the problem lies in how FFMPEG does the RGB->YUV conversion by default.  This option specifies the use of the bt709 color space for the conversion, instead of the default of bt601.  This fixes it for me - though please let me know if I'm doing something bad here!</p>

<pre><code>-vf scale=out_color_matrix=bt709
</code></pre>

CC BY-SA 3.0
2016-03-24T16:28:01.523Z
709 is default for HD, 601 for SD.
Gyan
CC BY-SA 3.0
2016-03-24T15:42:12.807Z
2016-03-24T15:42:12.807Z
Bryan Fordney
<p>I am attempting to encode "ProRes 4444" movies with ffmpeg.  Some research led me to the "prores_ks" encoder, which is the only one of ffmpeg's prores encoders that supports "4444".</p>

<p>I used this command to test it out (input excluded):</p>

<pre><code>-c:v prores_ks -f mov -profile:v 4444 test.mov
</code></pre>

<p>This produces a ProRes 4444 movie.  However, the colors appear darker than the original input.  After some research I came upon this option:</p>

<pre><code>-vf colormatrix=bt601:bt709
</code></pre>

<p>Adding this filter seems to fix the problem.  However, the file size is for some reason considerably bigger.  Also, I do not like the idea that a filter has to be performed during this encoding, as I want the highest possible quality.  Does anyone know of a way to overcome this "color shift" without a video filter?</p>

CC BY-SA 3.0
2016-02-29T22:31:50.740Z
The input is a PNG sequence.
Bryan Fordney
CC BY-SA 3.0
2016-03-01T17:15:51.140Z
I've tried both 8 and 16 bit, out of After Effects.  Here's a PNG and a MOV made with ffmpeg, using command `ffmpeg -r 24 -i colorbars_8bit.png -c:v prores_ks -profile:v 4444 colorbars_prores_ks.mov`: https://file.io/SeKH8I
Bryan Fordney
CC BY-SA 3.0
2016-03-01T18:01:47.153Z
Interestingly, Natron's "WriteFFmpeg" module does not seem to have this problem.
Bryan Fordney
<ffmpeg><quicktime><prores>
FFMPEG prores_ks 4444 color shift
Bryan Fordney
# FFMPEG prores_ks 4444 color shift

(Asked by: username_0 on 2016-02-18)

I am attempting to encode "ProRes 4444" movies with ffmpeg.  Some research led me to the "prores_ks" encoder, which is the only one of ffmpeg's prores encoders that supports "4444".
I used this command to test it out (input excluded):
-c:v prores_ks -f mov -profile:v 4444 test.mov

This produces a ProRes 4444 movie.  However, the colors appear darker than the original input.  After some research I came upon this option:
-vf colormatrix=bt601:bt709

Adding this filter seems to fix the problem.  However, the file size is for some reason considerably bigger.  Also, I do not like the idea that a filter has to be performed during this encoding, as I want the highest possible quality.  Does anyone know of a way to overcome this "color shift" without a video filter?

**Tags:** ffmpeg, quicktime, prores

> **Comments:**
> **username_0**: The input is a PNG sequence.  
> **username_0**: I've tried both 8 and 16 bit, out of After Effects.  Here's a PNG and a MOV made with ffmpeg, using command `ffmpeg -r 24 -i colorbars_8bit.png -c:v prores_ks -profile:v 4444 colorbars_prores_ks.mov`: https://file.io/SeKH8I  
> **username_0**: Interestingly, Natron's "WriteFFmpeg" module does not seem to have this problem.  

---

## 1 answers

### Answer by username_0 on 2016-03-24. Score: 1

I believe the problem lies in how FFMPEG does the RGB->YUV conversion by default.  This option specifies the use of the bt709 color space for the conversion, instead of the default of bt601.  This fixes it for me - though please let me know if I'm doing something bad here!
-vf scale=out_color_matrix=bt709

> **Comments:**
> **username_1**: 709 is default for HD, 601 for SD.  

---

