convert total pdf pages into images - command line

i have tried following command line for converting pdf to image , it works but not for all pages ,first page only converted into image

soffice --headless --invisible -convert-to png -outdir ./ ./sample.pdf

Could you please tell us a bew more details: OS and LibO version

The following will extract images from your into “dir” directory
pdfimages -all /path/file.pdf /dir/image-file-prefix
I don’t remember from what package this utility comes