Convert svg file to png / ico with Python

Introduction

• I'm not sure about the design or the front desk.
• During some work, I needed an ico file for my favicon, but the front desk person only gave me svg.
• I know that there is a conversion tool on an external site, but I don't want to use it because it is a work file.
• I asked to make an ico, but for the time being, I tried to find out how to do it with Python so that I could do it quickly at hand.
• I don't know if this method is appropriate, but I can do it for the time being.

environment

• Python 3.6.6

How to do it

When I googled lightly, there were many examples of converting in the order of svg-> png-> ico.

svg -> png

It seems that conversion of svg-> png can be done by using cairosvg.

Installation

$ pip install cairosvg

It seems that the executable file is included, so execute it as it is.

And an error ...

$ cairosvg sample.svg -o sample.png
Traceback (most recent call last):
  File "/Users/tommarute/miniconda3/envs/py366/bin/cairosvg", line 6, in <module>
    from cairosvg.__main__ import main
  File "/Users/tommarute/miniconda3/envs/py366/lib/python3.6/site-packages/cairosvg/__init__.py", line 42, in <module>
    from . import surface  # noqa isort:skip
  File "/Users/tommarute/miniconda3/envs/py366/lib/python3.6/site-packages/cairosvg/surface.py", line 28, in <module>
    from .defs import (
  File "/Users/tommarute/miniconda3/envs/py366/lib/python3.6/site-packages/cairosvg/defs.py", line 24, in <module>
    from .bounding_box import calculate_bounding_box, is_non_empty_bounding_box
  File "/Users/tommarute/miniconda3/envs/py366/lib/python3.6/site-packages/cairosvg/bounding_box.py", line 26, in <module>
    from .features import match_features
  File "/Users/tommarute/miniconda3/envs/py366/lib/python3.6/site-packages/cairosvg/features.py", line 25, in <module>
    LOCALE = locale.getdefaultlocale()[0] or ''
  File "/Users/tommarute/miniconda3/envs/py366/lib/python3.6/locale.py", line 562, in getdefaultlocale
    return _parse_localename(localename)
  File "/Users/tommarute/miniconda3/envs/py366/lib/python3.6/locale.py", line 490, in _parse_localename
    raise ValueError('unknown locale: %s' % localename)
ValueError: unknown locale: UTF-8

Somehow the locale seems to be unknown

Try to specify

$ LC_CTYPE="ja_JP.UTF-8" cairosvg sample.svg -o sample.png

I got it.

$ ls -ltr
total 16
-rw-r--r--  1 tommarute  user   348 Nov 17 22:15 sample.svg
-rw-r--r--  1 tommarute  user  1473 Nov 17 22:16 sample.png

png -> ico

It seems that png-> ico can be used with pillow.

Installation

$ pip install pillow

There is no executable file here, so use it as a library.

In [1]: from PIL import Image

In [2]: fn = r'sample.png'

In [3]: img = Image.open(fn)

In [4]: img.save('favicon.ico')

In [5]:

I got it.

$ ls -ltr
total 48
-rw-r--r--  1 tommarute  user    348 Nov 17 22:15 sample.svg
-rw-r--r--  1 tommarute  user   1473 Nov 17 22:16 sample.png
-rw-r--r--  1 tommarute  user  12993 Nov 17 22:20 favicon.ico

Finally

It's a little like that, so let's make a slightly better script.

import sys
import os
os.environ['LC_CTYPE'] = "ja_JP.UTF-8"
import cairosvg
from PIL import Image


def run(svg, ico):
    print(f'svg = {svg}')
    print(f'ico = {ico}')
    png = f'{svg}.png'
    cairosvg.svg2png(url=svg, write_to=png)
    img = Image.open(png)
    img.save(ico)
    print('Deleting temporary png file.')
    os.unlink(png)
    print('svg2ico has finished normally.')

def main():
    args = sys.argv
    run(args[1], args[2])


if __name__ == '__main__':
    main()

The end

reference

• https://stackoverflow.com/questions/45507/is-there-a-python-library-for-generating-ico-files