# eps figure (image) quality loss on including it in latex

I saw Included PNG appears blurry in PDF and How do I insert an image in LaTeX so it looks good on print? also etc. However, I am trying to include .eps images, which are generated using gnuplot. Still, there is a loss of details. Here is how I generate in gnuplot.

set term postscript eps color blacktext "Helvetica" 24
set output "filename.eps"


When I see .eps itself with evince, it looks fine, but after I use latex and make pdf using:

dvipdf PAPER.dvi  PAPER.pdf


the image does not look to be that clear. Here is the MWE:

\documentclass{article}
\usepackage{graphicx}
\begin{document}
\begin{figure}[htbp]
\centering
\includegraphics [scale=0.5] {rough}
\end{figure}
\end{document}


rough.eps is here: http://www.tempfiles.net/download/201208/256505/rough.html. It was generated as png using powerpoint, then changed to eps using inkscape. Those generated using gnuplot are my results, hence I shared this instead.

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Welcome to TeX.sx! Please add a minimal working example (MWE) that illustrates your problem. In particular, as TeX does not alter images, we probably need to have a link to an example image and .tex file. –  Joseph Wright Aug 10 '12 at 12:51
Also, what happens if you convert the .eps file itself directly to PDF using epstopdf and then use pdfLaTeX? –  Joseph Wright Aug 10 '12 at 12:52
Both eps and pdf are containers that can contain vector images or raster images (or a mixture of the two). If you convert any image into a raster image (e.g. png), it will stay rastered forever, no matter what format you can convert it to afterwards. –  matth Aug 10 '12 at 13:52
From your post it is not clear whether the image was created with gnuplot or Powerpoint. Could you clarify that? –  matth Aug 10 '12 at 13:55
Thanks. The rough.eps was created using powerpoint. Another file that I have was created using gnuplot, which contains experimental results. Your above answer "both eps.." is very helpful. Can you suggest workaround to create Powerpoint type block-diagrams in eps? –  user984260 Aug 10 '12 at 13:59

The main problem here seems to be the understanding of the difference between raster or pixel graphics on the one hand and vector or line graphics on the other hand. The difference is explained in the questions already linked by the OP or in the Wikipedia article on vector graphics.

Typical file formats for raster graphics are .jpg, .png, .gif or .tiff (read more here).
Programs for creating & editing raster graphics are Microsoft Paint, Photoshop or Gimp and many more.

Typical file formats for vector graphics are .eps, .pdf or .svg (read more here).
Programs for creating & editing vector graphics are Inkscape, Corel Draw, Adobe Illustrator and many more.

Most vector file formats can also contain raster graphics, e.g. as background decoration. Including or converting a .png file into a .pdf file does not make it a vector graphic.
On the other hand, converting a vector graphic into a raster graphic makes it a raster graphic forever, there is no way back (apart from vectorisation, which is usually as laborious as creating a new graphic from scratch).

gnuplot and also Matlab, Octave, matplotlib etc are capable of exporting vector graphics:

• Choose eps if your workflow is latex->dvi->ps->pdf.
• Choose pdf if your workflow is pdflatex->pdf.
• Choose .emf or .wmf iy you are using Microsoft Word.

The OP also asks about block diagrams created with MS PowerPoint. PowerPoint internaly uses vector graphics for block diagrams but does not allow export to vector graphics directly, not even to the vector formats developed by Microsoft (called .wmf and .emf). The workaround here is to export to pdf, either by "printing" to a pdf printer like Adobe Acrobat Distiller or pdfCreator, or by using the "save to pdf" function which is included in MS Office 2007 and newer. This approach also works for Excel diagrams.

As an alternative way to create plots and block diagrams, I would suggest to look at TikZ/PGF.

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This is matth's answer:

There is an easy solution: MS Office 2007 and newer can save to pdf (If you use Office 2003 or older, you can use e.g. pdfCreator). Those pdfs are vector images. So, you should create a Powerpoint presentation with one single slide, save that to pdf, then edit using Inkscape (crop, edit, etc) and save to pdf or eps. Mircosofts professional solution for technical drawings is Visio. Visio can save to various vector formats.

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