Re: Horizontalized scores

[David Kastrup]

"Chris Crossen" <address@hidden> writes:

>>> Chris Crossen:
>> > When I use GIMP to convert a pdf produced with Lilypond to a .png, I
>> > get nice crisp verticals and horizontals, no anti-aliasing. And, the
>> > note heads and other rounded parts are beautifully anti-aliased.
>
>> David Kastrup:
>> I don't think that GIMP does anything but call Ghostscript for the
> rendering
>> (though I might not me up-to-date with my knowledge).  So this would boil
>> down to figuring out the options it uses.
>> 
>
> Thank you, David, for pointing me in the right direction. And thanks to
> everyone who contributed to this thread for getting me this far along.
>
> The trick to getting the crisp horizontal and vertical lines while still
> getting anti-aliased curves is the ghostscript option -dGraphicsAlphaBits.
> When Lilypond produces a .png file it set this to 4. If you set it to 1
> instead, you get horizontal and vertical lines that aren't anti-aliased.

Not just horizontal and vertical lines.  Also things like circles.  The
appearance of, say, { b\1 b\2 b\3 b\4 } is a downside to this approach.

I just remembered another option:

Convert to PDF with -dstrokeadjust and then convert PDF to PNG with
pdftocairo.  This approach is likely one of the slowest, but it's
basically what I used to batch-test what PDF previewers like Evince
would be likely to deliver.

-- 
David Kastrup