Re: [Gnuplot-bugs] rgbimage shift-rotates the image along the x-axis

[Hans-Bernhard B. <HBB...@t-...>]

fredfriend wrote:

> Part of the problem, to my opinion, is that I (any probably more users)
> don't know the differences between all these bitmap/pixmap types and the
> gnuplot manual is not very descriptive about how to tailor a given
> bitmap/pixmap so it gets accepted by gnuplot.

Of course not.  There are virtually infinitely many image file formats, 
most of which don't contain their data in a packed format that gnuplot 
can't do anything with.  It would be madness to try and list recipes for 
(all variations of) all of them.

> It's probably not the role of gnuplot to describe file formats, but
> if it doesn't know what to do with the headers, where other programs
> do, then my conclusion (as a non-expert) is that gnuplot doesn't read
> (properly) PNM, PPM or whatever format.

Well, guess what: it doesn't.  Did it promise otherwise?

> So if gnuplot only accept images without the first (4) header lines, then I
> think it's a good thing to say/hint that in the manual.

That's not what it does, so it would be wrong to put that in the manual. 
  Gnuplot accepts raw binary image data.  If that's not what your input 
is, it's up to you to find out how your image file can be transformed 
into such a formats.