Adding Logo to PNG Image

Problem

You want to add your logo to a png image generated by OEDepict TK. See example in Table 1.

Table 1. Example of adding a logo to a molecule image
image generated by OEDepict TK image with OpenEye logo
../_images/molecule.png ../_images/molecule-logo.png

Ingredients

Difficulty Level

../_images/chilly2.png

Download

Download code

addlogo.py

See also the Usage subsection.

Solution

OEDepict TK does not provide functionality to paste a png image into the png image generated for a molecule. But this can be easily achieved by using the Pillow Python image processing library. The following code illustrates how to superimpose a logo in the bottom right corner of the molecule image.

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#!/usr/bin/env python3
import sys
try:
    from PIL import Image
except ImportError:
    print("Please install Pillow from: https://pypi.python.org/pypi/Pillow/3.0.0")
    sys.exit(1)


def main(argv=[__name__]):

    if len(sys.argv) != 4:
        print("Usage %s <image> <logoimage> <outimage>" % argv[0])
        return 1

    inimage, logo, outimage = sys.argv[1], sys.argv[2], sys.argv[3]
    add_logo(inimage, logo, outimage)

    return 0


def add_logo(mfname, lfname, outfname):

    mimage = Image.open(mfname)
    limage = Image.open(lfname)

    # resize logo
    wsize = int(min(mimage.size[0], mimage.size[1]) * 0.25)
    wpercent = (wsize / float(limage.size[0]))
    hsize = int((float(limage.size[1]) * float(wpercent)))

    simage = limage.resize((wsize, hsize))
    mbox = mimage.getbbox()
    sbox = simage.getbbox()

    # right bottom corner
    box = (mbox[2] - sbox[2], mbox[3] - sbox[3])
    mimage.paste(simage, box)
    mimage.save(outfname)


if __name__ == "__main__":
    sys.exit(main(sys.argv))

Usage

Usage

addlogo.py script with molecule.png and logo.png test images

prompt > python3 addlogo.py molecule.png logo.png molecule-logo.png

Discussion

To install Pillow in a Python 3 conda environment:

prompt > conda create -n oecookbook python=3
prompt > source activate oecookbook
(oecookbook) prompt > pip install Pillow