parallel: Warning: $HOME not set. Using /tmp.
convert-im6.q16: Expected 8192 bytes; found 7377 bytes `gnomonic_corr_grid.png' @ warning/png.c/MagickPNGWarningHandler/1654.
convert-im6.q16: Read Exception `gnomonic_corr_grid.png' @ error/png.c/MagickPNGErrorHandler/1628.
convert-im6.q16: no images defined `tmp.png' @ error/convert.c/ConvertImageCommand/3258.
rm: cannot remove 'tmp.png': No such file or directory