pnmquant
Quantize the colors in a PNM image into a smaller set. This command is a combination of pnmcolormap and pnmremap and accepts the union of their options, except -mapfile. More information: <https://netpbm.sourceforge.net/doc/pnmquant.html>.
RUN apt-get update && \
apt-get install -y netpbm
RUN apt-get update && \
apt-get install -y netpbm
RUN pacman -S --noconfirm netpbm
RUN apt-get update && \
apt-get install -y netpbm
RUN yum install -y netpbm-progs
RUN dnf install -y netpbm-progs
RUN apt-get update && \
apt-get install -y netpbm