Where to add x264 encoder commands for the cli to grab it

[Mizitras]

Me doing a simple re-encoding:

I start-up MeGui, go to Tools - AVS Script Creator - Add the video; click on Save;
Encoder settings x265 -> I choose Config at the right, new window comes up;
'X264 configuration dialog"
I go to the last tab, 'Misc' and add at the top where it reads "command line commands"
--vf "scale=in_range=mpegut_range=full" to have a x265 inputfile, with a different colorspace, be stretched to the colorspace for x264
Doesn't work.

I add the following, instead of the above:
--pix_fmt yuvj420p
Also, errors.

I don't think the parameters are wrong, I'm 90% sure I'm adding this in the wrong place.

[poisondeathray]

Me doing a simple re-encoding:

I start-up MeGui, go to Tools - AVS Script Creator - Add the video; click on Save;
Encoder settings x265 -> I choose Config at the right, new window comes up;
'X264 configuration dialog"
I go to the last tab, 'Misc' and add at the top where it reads "command line commands"
--vf "scale=in_range=mpegut_range=full" to have a x265 inputfile, with a different colorspace, be stretched to the colorspace for x264
Doesn't work.

I add the following, instead of the above:
--pix_fmt yuvj420p
Also, errors.

I don't think the parameters are wrong, I'm 90% sure I'm adding this in the wrong place.

-vf scale and -pix_fmt are for ffmpeg, not x264 or x265 cli (which megui uses)

[jagabo]

Also, you almost never want to encode full range video. Few devices will play it properly.

[Mizitras]

I browsed through all of the x264 parameters, but none allows me to change the color space.
This is .... impossible when using Megui and sending the videostream to x264 encoder ? Or does it need another step ?