[R] PowerPoint

Marc Schwartz (via MN) mschwartz at mn.rr.com
Fri Jun 23 18:27:00 CEST 2006


On Fri, 2006-06-23 at 18:16 +0200, Philipp Pagel wrote:
> On Fri, Jun 23, 2006 at 09:21:37AM -0400, Gabor Grothendieck wrote:
> > Note that jpg, bmp and png are in less desirable bit mapped formats whereas
> > eps is in a more desirable vector format (magnification and shrinking does
> > not involve loss of info) and so would be preferable from a quality
> > viewpoint.
> 
> In addition to seconding the above statement I'd like to add that in
> cases where you are forced to use a bitmap format png tends to produce
> much better results than jpg where line drawings (e.g. most plots) are
> concerned. JPG format on the other hand is great for anyting which can be
> discirbed as photography-like. jpg images of plots tend to suffer from
> bad artifacts...
> 
> cu
> 	Philipp


That is generally because png files are not compressed, whereas jpg
files are. 

The compression algorithms that are typically used are lossy, which
means that you give up image quality in order to gain the reduction in
file size. The greater the compression you use, the greater the loss in
image quality.

Yet another reason to use EPS for plots.

HTH,

Marc Schwartz



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