Error in converting a PDF to a PNG in ImageMagick

Solution 1:

Try adding -colorspace RGB before the outfile name.

convert -density 300 PointOnLine.pdf -quality 90 -colorspace RGB PointOnLine.png

Solution 2:

The documentation says this:

PNG RW Portable Network Graphics Requires libpng-1.0.11 or later, libpng-1.2.5 or later recommended. The PNG specification does not support pixels-per-inch units, only pixels-per-centimeter. To avoid reading a particular associated image profile, use -define profile:skip=name (e.g. profile:skip=ICC).

So try adding -define profile:skip=ICC (or skip="*") before the outfile name.

See also: documentation on the define command