Re: Alternating text and music

[David Wright]

On Sat 27 Jul 2019 at 12:48:40 (-0700), Aaron Hill wrote:
> On 2019-07-27 12:03 pm, David Wright wrote:
> > On Sat 27 Jul 2019 at 18:57:35 (+0200), David Kastrup wrote:
> > > David Wright <address@hidden> writes:
> > > > I would advise against that because PNGs are rastered. The hint is in
> > > > the name: portable-Network-graphics.
> > > 
> > > Uh, what in the name indicates rasterisation?
> > 
> > Perhaps I was a little oblique: "Network" indicates that the format is
> > designed for transfer of images over the network, rather than between
> > local applications. Compromises are made in favour of smaller size and
> > higher transmission speed, rather than maintaining resolution; not
> > desirable for engraving pages of music.
> 
> Vector formats are equally as well-suited for transmission over a
> network.  PNG might have been created with the Web in mind; but to me,
> nothing about networking would seem to prefer raster over vector.

I wasn't trying to discuss the relative merits of either for network
transmission; rather, which was better in the document-generating
workflow of LP → <intermediate format(s)> → PDF document.

> In
> fact, vector is pretty common on the Web these days, whether in the
> form of SVG or web fonts.

I can't comment on that, having never seen any statistics. What was
required on the Web was a method of transferring images, both
diagrammatic and photographic. GIF filled that role, especially in the
days of 8bit colour displays, but was encumbered by patents, which was
why PNGs were developed. If SVGs had come to the party earlier,
perhaps no one would have used raster formats for images that suit
SVG. But that wasn't going to happen until browsers could render them.

> > I'm not overconcerned whether people see this as a hint not to use
> > PNGs in this workflow. But I assume you're not supporting their
> > use, are you.
> 
> This is purely anecdotal: I use PNGs in my workflow with no issues
> whatsoever.  Mind you, I am using them for projection not print.  In
> practice, I have LilyPond rasterize at a higher DPI than I need for
> the target resolution and then use ImageMagick to down-sample so I can
> better control the quality of smoothing/anti-aliasing.  It is
> admittedly a little overkill, as I doubt members of the congregation
> could notice the finer details given the distance to the screens.

You have the advantage of me: I have no idea what device you're
using to project the final image, and the formats it supports, nor
what intermediate steps you're making between LP and said projector,
apart from the smoothing/antialiasing mentioned (which wouldn't be
required for vector graphics anyway).

> For the record, when I do use LilyPond specifically for print, I
> almost always use PDF as the output.

That seems reasonable; I always do.

> On occasion, I have had to use a
> raster format when I was compositing music within a document.

Sure, when that's all that's available.

> In that
> case, I just crank up the DPI in order to saturate the resolution of
> the printer.

Oh, that suggests *you* made the raster, rather than using a
pre-existing one. In which case, what benefit are you getting
from making the raster in the first place?

> Again, I suspect few people would be able to tell the
> difference given the printed document.

Yes, I presume the printer will be the greatest source of degradation
in the final output. But I don't see why you'd want to introduce any
more into the workflow when there's no need.

BTW I assumed, perhaps wrongly, that DAK might have "supported" the
use of rasters/PNGs as an intermediate format. So apologies if your
anecdote here was not intended to show a *preference* for them over
the PDF workflow I posted earlier. But if it was, then I'd maintain
that one gets a better product using PDFs, hence my advice to use them.

Cheers,
David.