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Python Imaging Library - Text rendering

I'm trying to render some text using PIL, but the result that comes out is, frankly, crap.

For example, here's some text I wrote in Photoshop:

PhotoShop

and what comes out of PIL:

PIL

As you can see, the results from PIL is less than satisfactory. Maybe I'm just being picky, but is there any way to draw text using PIL that gets results more close to my reference image?

Here's the code I'm using on Python 2.7 with PIL 1.1.7

image = Image.new("RGBA", (288,432), (255,255,255))
usr_font = ImageFont.truetype("resources/HelveticaNeueLight.ttf", 25)
d_usr = ImageDraw.Draw(image)
d_usr = d_usr.text((105,280), "Travis L.",(0,0,0), font=usr_font)
like image 221
exiva Avatar asked Mar 24 '11 04:03

exiva


4 Answers

I came up with my own solution that I find acceptable.

What I did was render the text large, like 3x the size it needs to be then scale it resize it down with antialiasing, it's not 100% perfect, but it's a hell of a lot better than default, and doesn't require cairo or pango.

for example,

image = Image.new("RGBA", (600,150), (255,255,255))
draw = ImageDraw.Draw(image)
font = ImageFont.truetype("resources/HelveticaNeueLight.ttf", fontsize)

draw.text((10, 0), txt, (0,0,0), font=font)
img_resized = image.resize((188,45), Image.ANTIALIAS)

and you endup with this result,

final result

which is a lot better than what I was getting before with the same font.

like image 87
exiva Avatar answered Oct 20 '22 12:10

exiva


Try using pycairo - the python bindings for the Cairo drawing library -- it is usefull for more refined drawing, with antialiased lines, and such - and you can generate vector based images as well

Correctly handling fonts, and layout is complicated, and requires the use of the "pango" and "pangocairo" libraries as well. Although they are made for serious font work (all GTK+ widgets do use pango for font rendering), the available docuemtnation and examples are extremely poor.

The sample bellow shows the prints available in the system and renders the sample text in a font family passed as parameter on the command line.

# -*- coding: utf-8 -*-
import cairo
import pango
import pangocairo
import sys

surf = cairo.ImageSurface(cairo.FORMAT_ARGB32, 320, 120)
context = cairo.Context(surf)

#draw a background rectangle:
context.rectangle(0,0,320,120)
context.set_source_rgb(1, 1, 1)
context.fill()

#get font families:

font_map = pangocairo.cairo_font_map_get_default()
families = font_map.list_families()

# to see family names:
print [f.get_name() for f in   font_map.list_families()]

#context.set_antialias(cairo.ANTIALIAS_SUBPIXEL)

# Positions drawing origin so that the text desired top-let corner is at 0,0
context.translate(50,25)

pangocairo_context = pangocairo.CairoContext(context)
pangocairo_context.set_antialias(cairo.ANTIALIAS_SUBPIXEL)

layout = pangocairo_context.create_layout()
fontname = sys.argv[1] if len(sys.argv) >= 2 else "Sans"
font = pango.FontDescription(fontname + " 25")
layout.set_font_description(font)

layout.set_text(u"Travis L.")
context.set_source_rgb(0, 0, 0)
pangocairo_context.update_layout(layout)
pangocairo_context.show_layout(layout)

with open("cairo_text.png", "wb") as image_file:
    surf.write_to_png(image_file)

Rendred image

like image 40
jsbueno Avatar answered Oct 20 '22 11:10

jsbueno


I've never used PIL, but a quick review of the documentation for the Draw method indicates that PIL provides a way to render simple graphics. Photoshop provides a way to render complex graphics. To get anywhere close to Photoshop-like results requires, at a minimum, font hinting and anti-aliasing. PIL's documentation doesn't even hint at having such capabilities. You may want to look at using an external tool that might do a better job of rendering text on images. For example, ImageMagick (you'll want to use the 8-bit version, which handles standard 24-bit RGB). You can find some text drawing samples here: http://www.imagemagick.org/Usage/draw/

like image 13
dave-holm Avatar answered Oct 20 '22 12:10

dave-holm


Suggestion: use Wand or a different Imaging library

Here's an example with wand -

from wand.color import Color
from wand.image import Image
from wand.drawing import Drawing
from wand.compat import nested

with Drawing() as draw:
    with Image(width=1000, height=100, background=Color('lightblue')) as img:
        draw.font_family = 'Indie Flower'
        draw.font_size = 40.0
        draw.push()
        draw.fill_color = Color('hsl(0%, 0%, 0%)')
        draw.text(0,int(img.height/2 + 20), 'Hello, world!')
        draw.pop()
        draw(img)
        img.save(filename='image.png')

image that comes out-

like image 6
Aditya Shankar Avatar answered Oct 20 '22 13:10

Aditya Shankar