Convert images to EPS format

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Introduction

.eps is a common used format of images in academic writting. If you want to convert hundreds of .jpg or .png. formats to .eps, the command convert in Linux system provides a good solution.

ImageMagick

The command convert is a tool from the tool ImageMagick, includes a number of command-line utilities for manipulating images. Please install it if convert is not found.

Another utility from is identify. It can output the size and other information of the interested image, e.g.,

identify Behdinan1998.png

The output is:

Behdinan1998.png PNG 1103x792 1103x792+0+0 8-bit sRGB 96.2KB 0.000u 0:00.000

Convert

The simplest way is,

$ convert src.png dst.eps

To change the image size,

$ convert  -resize 1920×1080 src.png dst.eps
# Change the size according to the ratio
$ convert  -resize 50%x100%! src.png dst.eps
# Change the size according to the width and keep the origin aspect ratio
$ convert  -resize 50%x100% src.png dst.eps

To change the dpi of the image,

$ convert  -density 300 -resize 1920×1080 src.png dst.eps

To rotate the figure (degree),

$ convert  -rotate 90 src.png dst.eps

To add some text in the figure,

$ convert -fill black -pointsize 60 -font Times -draw 'text 100,800 "NAOE" ‘ src.png dst.png

However, the -destiny will lead to as large as hundreds of MB for one image. To solve this problem, we use a pdf file as a temporary file.

$ convert -density 300 -resize 1920×1080 src.png dst.pdf && pdftops -eps dst.pdf

The output file is not large and clear enough.

Error during converting

When you first use conert src.png dst.pdf, maybe the error message occurs:

convert: not authorized `pictures.pdf' @ error/constitute.c/WriteImage/1028

As a temporary fix, you can edit /etc/ImageMagick-6/policy.xml and change the PDF rights from none to read|write there.

[Reference]

The EPS file can not be converted to PNG using this tool. Please tell me if you know how.

An example

Here is a shell script for you. It can convert all the png files in the current directory to EPS files. The original images are not removed.

for origin_image in `ls *.png`
do
    file_name = $(basename $origin_image .png)
    convert -density 300 -resize 1920×1080 $file_name.png $file_name.pdf
    pdftops -eps $file_name.pdf
done

Enjoy it.

Reward