I achieve good results using ImageMagick convert with the monochrome option:
convert -monochrome input.png output.pcx
----- Original Message -----
Date: 22.06.2013 16:24:10
Subject: [Gimp-user] Monochrome 1-bit export?
> Hi guys.
> I used to save images in 1-bit PCX format, as required by several label
> (thermal transfer) printers. I can't find any way to do that anymore.
> Export to PCX does not give any options, and exports 24bit color.
> Even after changing the image format to indexed, and selecting 1-bit B/W,
> export to PCX is still
> 8-bit colour, 300 x 300 dpi, RLE compressed
> Any way to accomplish
> 1-bit colour, 72 x 72 dpi, RLE compressed
> Note that another accepted format is monochrome BMP, but this does not
> seem to work either in GIMP. The only options offered are RGB.
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