Global colour_command_get (size_t bytes_per_line)

shared component, because the monochrome usecase is only a special usecase of the colour usecase

Please drop me a note, if you know other QL printers which provide this feature as well.

Global cups_ql_medium_detect (struct qldriver *ql)

Can be called in cups_ql_driver_init() as well

Global cups_ql_next_colour_line_read (struct qldriver *ql, struct halftone_converter *cnv_black, struct halftone_converter *cnv_red)

The input raster can be smaller than the required line width. In this case the labels are smaller (for example) and the raster must be right aligned.

Global fraction (double no)

can lrint() be used here instead?

Global high_resoultion_setup (struct qldriver *ql)

This function still needs to be implemented

Global margin_setup (struct qldriver *ql)

Integrate the 3 mm top/bottom margins into the continuous length paper definition?

Global ql_notification_disable (struct qldriver *ql)

But it would be useful to have a back channel!

Global ql_page_header_generate (struct qldriver *ql, int first_time)

Deal with QL_FAST_PRINT/QL_QUALITY_PRINT for monochrome use case

Do the QL_QUALITY_PRINT and QL_HIGH_RESOLUTION bits depend on each other?

Deal with auto cut setting and when to cut (and if the printer has a cutter). To make it simple: only "cut at end" and "cut each" should be supported

Global quantize_grey_pixel (const struct halftone_converter *cnv, signed int v)

Ensure the returned value fits into a 'signed short'

Global rolls []

All transport tape sizes are still to be checked