Can x265 do grayscale in ffmpeg?

[wallywalters]

I can convert color video to gray in x264 with the "-vf format=gray" specification, but using that syntax with x265 blacks out the entire image. Is there an equivalent x265 instruction? Thanks.

[Chris K]

It does fine for me!

It's probably at your playback side. I use LAV Filters for playback.