[FFmpeg-user] Question about colorspace conversion

[m_cik at o2.pl]

I'm little confused about using colorspace conversion, transformation
characteristics. What I'm doing is extracting frames from HDR movie to PNG
files(PNG files will be used in another project). I run following command:
`ffmpeg -i data/hdr_movie.mkv -pix_fmt rgb48be -s:v 1920x1080
-color_primaries 9 -color_trc 16 -colorspace 9 -color_range 1
frames/frame_%06d.png`

ffprobe for data/hdr_movie.mkv is `Video: hevc (Main 10), yuv420p10le(tv)`

If I run the ffmpeg command, do I really convert colorspace? Or do I
specify colorspace of output frame? Should I also run proper filter, which
will do conversion? And additional question, what is the order of
converting steps? colorspace, characteristics, matrix?