Eric Firing wrote: > Jozef Vesely wrote: > >> Hello matplotlib developers, >> >> I have implemented "svg.image_noscale" feature for ps and pdf backends. I >> think >> that resampling/scaling should be avoided, when vector format can scale image >> itself. >> Unfortunately, the quality of interpolation is often subpar compared to what matplotlib (via Agg) provides. Worse, the quality will be different when using Acrobat Reader vs. xpdf, for instance. I don't think zooming in on individual pixels of data in Acroread is something we really are trying to support anyway -- for that you should use an interactive matplotlib GUI. The purpose of pdf, imho, is really for printing. In that case, you're likely to get better results and smaller file sizes by knowing the maximum resolution of your output device and letting matplotlib resample it -- and resample it with a method that is appropriate for the data, not the one in the printer or Acrobat that is (probably) optimized for photographs of the real world or whatever the driver is currently set to. > It seems to me best if there is an option to scale or not; depending on > the situation, one might want to generate a file with images downscaled. > Right. All the above notwithstanding, I don't have a problem with this being a user option, I just can't imagine using it myself. > >> One advantage is that original image can be recovered from final file. >> Moreover >> as it is vector format it should be dpi independent and always provide >> maximum >> possible quality - that's original data. >> The original image can theoretically be recovered from the final file. But not the original data, which may be floating point etc. If you anticipate users of your plot to need the original data, just distribute the original data alongside the plot. >> As for svg backend I have commented some transformation changes which >> I don't understand and which result in misaligned image and axes. >> Without it the misalignment is still there but smaller. >> Thanks for that. I'm not sure why that code is there. I see it looks much better without it. >> I have also removed MixedModeRenderer from svg as it conflicts with >> "svg.image_noscale" >> and does not seem to be used. >> I think it would be better to turn off mixed mode rendering only when svg.image_noscale is True. >> > > I think having the option of using the MixedModeRenderer is important in > the long run for the vector backends; without it, one can end up with > completely unwieldy and potentially unrenderable files. I'm not sure > what its status is at present; I think Mike got it working to a > considerable extent, but didn't quite finish, and therefore left it > temporarily disabled. > It's fully functional in all the backends where it makes sense. The part that is unfinished is the user interface -- how to turn the functionality on and off. We couldn't find both a general and easy way to do it. But it would be nice to have another go at it.
Mike -- Michael Droettboom Science Software Branch Operations and Engineering Division Space Telescope Science Institute Operated by AURA for NASA ------------------------------------------------------------------------- This SF.Net email is sponsored by the Moblin Your Move Developer's challenge Build the coolest Linux based applications with Moblin SDK & win great prizes Grand prize is a trip for two to an Open Source event anywhere in the world http://moblin-contest.org/redirect.php?banner_id=100&url=/ _______________________________________________ Matplotlib-devel mailing list Matplotlib-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/matplotlib-devel
