I'm trying to set the profile level of libx265 to mainstillpicture using ffmpeg. But I can't seem to do so. I'm basically trying to encode every frame as intra frame (only spatial encoding) with no temporal encoding.

I've tried the following commands

```
ffmpeg -f rawvideo -vcodec rawvideo -s 3840x2160 -r 30 -pix_fmt yuv420p -i <input_filename> -c:v libx265 -b:v 45000k -preset veryslow -profile:v mainstillpicture <output_filename>

```

and

```
ffmpeg -f rawvideo -vcodec rawvideo -s 3840x2160 -r 30 -pix_fmt yuv420p -i <input_filename> -c:v libx265 -b:v 45000k -preset veryslow -profile:v 3 <output_filename>

```