466
votes

I have a SVG file that has a defined size of 16x16. When I use ImageMagick's convert program to convert it into a PNG, then I get a 16x16 pixel PNG which is way too small:

convert test.svg test.png

I need to specify the pixel size of the output PNG. -size parameter seems to be ignored, -scale parameter scales the PNG after it has been converted to PNG. The best result up to now I got by using the -density parameter:

convert -density 1200 test.svg test.png

But I'm not satisfied, because I want to specify the output size in pixels without doing math to calculate the density value. So I want to do something like this:

convert -setTheOutputSizeOfThePng 1024x1024 test.svg test.png

So what is the magic parameter I have to use here?

19
e.g. -size 1024x1024 is working fine, what is your imagemagick version?Dejan Marjanović
ImageMagick-6.9.0-Q16. convert -resize 1024x1024 foo.svg foo.png works fine.Jichao
@Jichao -resize just stretches the converted image, with poor quality results.Elist
convert -size 1024x1024 test.svg test.png works fine with ImageMagick 7.0.7-0 Q16 (current version in Chocolatey repo for Windows). Just make sure that -size appears before the input filename, else a 16x16 picture will be upscaled to give a blurry result.Futal

19 Answers

600
votes

I haven't been able to get good results from ImageMagick in this instance, but Inkscape does a nice job of scaling an SVG on Linux and Windows:

inkscape -z -w 1024 -h 1024 input.svg -e output.png

Inkscape 1.0 users, please note that the command line arguments have changed:

inkscape -w 1024 -h 1024 input.svg -o output.png

Note that you can omit one of the width/height parameters to have the other parameter scaled automatically based on the input image dimensions.

Here's the result of scaling a 16x16 SVG to a 200x200 PNG using this command:

enter image description here

enter image description here

167
votes

Try svgexport:

svgexport input.svg output.png 64x
svgexport input.svg output.png 1024:1024

svgexport is a simple cross-platform command line tool that I have made for exporting svg files to jpg and png, see here for more options. To install svgexport install npm, then run:

npm install svgexport -g

Edit: If you find an issue with the library, please submit it on GitHub, thanks!

128
votes

This is not perfect but it does the job.

convert -density 1200 -resize 200x200 source.svg target.png

Basically it increases the DPI high enough (just use an educated/safe guess) that resizing is done with adequate quality. I was trying to find a proper solution to this but after a while decided this was good enough for my current need.

Note: Use 200x200! to force the given resolution

55
votes

If you are on MacOS X and having problems with Imagemagick's convert, you might try reinstalling it with RSVG lib. Using HomeBrew:

brew remove imagemagick
brew install imagemagick --with-librsvg

Verify that it's delegating correctly:

$ convert -version
Version: ImageMagick 6.8.9-8 Q16 x86_64 2014-12-17 http://www.imagemagick.org
Copyright: Copyright (C) 1999-2014 ImageMagick Studio LLC
Features: DPC Modules
Delegates: bzlib cairo fontconfig freetype jng jpeg lcms ltdl lzma png rsvg tiff xml zlib

It should display rsvg.

47
votes

Inkscape doesn't seem to work when svg units are not px (e.g. cm). I got a blank image. Maybe, it could be fixed by twiddling the dpi, but it was too troublesome.

Svgexport is a node.js program and so not generally useful.

Imagemagick's convert works ok with:

 ~$ convert -background none -size 1024x1024 infile.svg outfile.png

If you use -resize, the image is fuzzy and the file is much larger.

BEST

~$ rsvg  -w 1024 -h 1024 infile.svg  outfile.png

It is fastest, has the fewest dependencies, and the output is about 30% smaller than convert. Install librsvg2-bin to get it. There does not appear to be a man page but you can type:

~$ rsvg --help

to get some assistance. Simple is good.

20
votes

After following the steps in Jose Alban's answer, I was able to get ImageMagick to work just fine using the following command:

convert -density 1536 -background none -resize 100x100 input.svg output-100.png

The number 1536 comes from a ballpark estimate of density, see this answer for more information.

17
votes

In order to rescale the image, the option -density should be used. As far as I know the standard density is 72 and maps the size 1:1. If you want the output png to be twice as big as the original svg, set the density to 72*2=144:

convert -density 144 source.svg target.png
11
votes

In ImageMagick, one gets a better SVG rendering if one uses Inkscape or RSVG with ImageMagick than its own internal MSVG/XML rendered. RSVG is a delegate that needs to be installed with ImageMagick. If Inkscape is installed on the system, ImageMagick will use it automatically. I use Inkscape in ImageMagick below.

There is no "magic" parameter that will do what you want.

But, one can compute very simply the exact density needed to render the output.

Here is a small 50x50 button when rendered at the default density of 96:

convert button.svg button1.png


enter image description here

Suppose we want the output to be 500. The input is 50 at default density of 96 (older versions of Inkscape may be using 92). So you can compute the needed density in proportion to the ratios of the dimensions and the densities.

512/50 = X/96
X = 96*512/50 = 983


convert -density 983 button.svg button2.png


enter image description here

In ImageMagick 7, you can do the computation in-line as follows:

magick -density "%[fx:96*512/50]" button.svg button3.png

or

in_size=50
in_density=96
out_size=512

magick -density "%[fx:$in_density*$out_size/$in_size]" button.svg button3.png
8
votes

On macOS using brew, using librsvg directly works well

brew install librsvg
rsvg-convert test.svg -o test.png

Many options are available via rsvg-convert --help

7
votes

why don't you give a try to inkscape command line, this is my bat file to convert all svg in this dir to png:

FOR %%x IN (*.svg) DO C:\Ink\App\Inkscape\inkscape.exe %%x -z --export-dpi=500 --export-area-drawing --export-png="%%~nx.png"

7
votes

For simple SVG to PNG conversion I found cairosvg (https://cairosvg.org/) performs better than ImageMagick. Steps for install and running on all SVG files in your directory.

pip3 install cairosvg

Open a python shell in the directory which contains your .svg files and run:

import os
import cairosvg

for file in os.listdir('.'):
    name = file.split('.svg')[0]
    cairosvg.svg2png(url=name+'.svg',write_to=name+'.png') 

This will also ensure you don't overwrite your original .svg files, but will keep the same name. You can then move all your .png files to another directory with:

$ mv *.png [new directory]
5
votes

This is what worked for me and would be the easiest to run.

find . -type f -name "*.svg" -exec bash -c 'rsvg-convert -h 1000  $0 > $0.png' {} \;
rename 's/svg\.png/png/' *

This will loop all the files in your current folder and sub folder and look for .svg files and will convert it to png with transparent background.

Make sure you have installed the librsvg and rename util

brew install librsvg
brew install rename
4
votes

I came to this post - but I just wanted to do the conversion by batch and quick without the usage of any parameters (due to several files with different sizes).

rsvg drawing.svg drawing.png

For me the requirements were probably a bit easier than for the original author. (Wanted to use SVGs in MS PowerPoint, but it doesn't allow)

4
votes

One thing that just bit me was setting the -density AFTER the input file name. That didn't work. Moving it to the first option in convert (before anything else) made it work (for me, YMMV, etc).

4
votes

Without librsvg, you may get a black png/jpeg image. We have to install librsvg to convert svg file with imagemagick.

Ubuntu

 sudo apt-get install imagemagick librsvg
 convert -density 1200 test.svg test.png

MacOS

 brew install imagemagick librsvg
 convert -density 1200 test.svg test.png

2
votes

On Linux with Inkscape 1.0 to convert from svg to png need to use

inkscape -w 1024 -h 1024 input.svg --export-file output.png

not

inkscape -w 1024 -h 1024 input.svg --export-filename output.png
1
votes

I've solved this issue through changing the width and height attributes of the <svg> tag to match my intended output size and then converting it using ImageMagick. Works like a charm.

Here's my Python code, a function that will return the JPG file's content:

import gzip, re, os
from ynlib.files import ReadFromFile, WriteToFile
from ynlib.system import Execute
from xml.dom.minidom import parse, parseString


def SVGToJPGInMemory(svgPath, newWidth, backgroundColor):

    tempPath = os.path.join(self.rootFolder, 'data')
    fileNameRoot = 'temp_' + str(image.getID())

    if svgPath.lower().endswith('svgz'):
        svg = gzip.open(svgPath, 'rb').read()
    else:
        svg = ReadFromFile(svgPath)

    xmldoc = parseString(svg)

    width = float(xmldoc.getElementsByTagName("svg")[0].attributes['width'].value.split('px')[0])
    height = float(xmldoc.getElementsByTagName("svg")[0].attributes['height'].value.split('px')[0])

    newHeight = int(newWidth / width * height) 

    xmldoc.getElementsByTagName("svg")[0].attributes['width'].value = '%spx' % newWidth
    xmldoc.getElementsByTagName("svg")[0].attributes['height'].value = '%spx' % newHeight

    WriteToFile(os.path.join(tempPath, fileNameRoot + '.svg'), xmldoc.toxml())
    Execute('convert -background "%s" %s %s' % (backgroundColor, os.path.join(tempPath, fileNameRoot + '.svg'), os.path.join(tempPath, fileNameRoot + '.jpg')))

    jpg = open(os.path.join(tempPath, fileNameRoot + '.jpg'), 'rb').read()

    os.remove(os.path.join(tempPath, fileNameRoot + '.jpg'))
    os.remove(os.path.join(tempPath, fileNameRoot + '.svg'))

    return jpg
1
votes

The top answer by @808sound did not work for me. I wanted to resize Kenney.nl UI Pack

and got Kenney UI Pack messed up

So instead I opened up Inkscape, then went to File, Export as PNG fileand a GUI box popped up that allowed me to set the exact dimensions I needed.

Version on Ubuntu 16.04 Linux: Inkscape 0.91 (September 2016)

(This image is from Kenney.nl's asset packs by the way)

0
votes

Transparent background, exported at target height/size using ImageMagick 7:

magick -background none -size x1080 in.svg out.png

One-liner mass converter:

for i in *svg; do magick -background none -size x1080 "$i" "${i%svg}png"; done