Develop Reference

Pillow pasting transparent image shows black image

I'm trying to use Pillow to paste an image with a transparent background onto a background image.
The background is a simple color background, and the transparent background image is as follows:
The transparent image
The code I'm using is below (the path is deliberately incorrect):
backgnd = Image.open("images/background.png")
backgnd.convert("RGBA")
body = Image.open("images/Untitled.png")
body.convert("RGBA")
backgnd.paste(body, (0,0), body)
backgnd.show()
The resulting image is as follows:
The resulting image, being all black
I've tried using the alpha_composite method, but it returns ValueError: image has wrong mode.

Try: backgnd.paste(body, (0,0), mask=body)

How to preserve the original colors of an image after adding text to it using PIL Python?

I am trying to add some text on my image using PIL, see the code below,
from PIL import Image
from PIL import ImageFont
from PIL import ImageDraw
import sys
image = Image.open('image.png')
draw = ImageDraw.Draw(image)
font = ImageFont.truetype('arial',40)
draw.text((700, 470),'Text',(0,0,0),font=font)
img.save('out-image.png','PNG')
But I lost the original colors of the image, see below images,
Original Image
After adding text
How I can preserve the original colors.
Thank You

That looks like a bug in PIL to me. I think it is because your image is palettised and the draw.text() is messing up the palette.
For a work-around, you can convert to an RGB image when you open it to avoid palette issues. Change to this:
image = Image.open('image.png').convert('RGB')

Transparency with Python Image Library

I'm trying to place a PNG watermark with partial transparency on top of a Facebook profile pic (jpg) using the Python Image Library. The part that should be transparent simply comes off as white. Here's my code:
con = urllib2.urlopen('facebook_link_to_profile_pic')
im = Image.open(cStringIO.StringIO(con.read()))
overlayCon = urllib2.urlopen('link_to_overlay')
overlay = Image.open(cStringIO.StringIO(overlayCon.read()))
im.paste(overlay, (0, 0))
im.save('name', 'jpeg', quality=100)
I've tried a few different ways, but haven't gotten anything to work. Any help is appreciated.

The 3rd option to paste is a mask (see the docs). It accepts an RGBA image, so the simplest solution is to use your overlay image again: im.paste(overlay, (0, 0), overlay).

Transparent PNG in PIL turns out not to be transparent

I have been hitting my head against the wall for a while with this, so maybe someone out there can help.
I'm using PIL to open a PNG with transparent background and some random black scribbles, and trying to put it on top of another PNG (with no transparency), then save it to a third file.
It comes out all black at the end, which is irritating, because I didn't tell it to be black.
I've tested this with multiple proposed fixes from other posts. The image opens in RGBA format, and it's still messed up.
Also, this program is supposed to deal with all sorts of file formats, which is why I'm using PIL. Ironic that the first format I tried is all screwy.
Any help would be appreciated. Here's the code:
from PIL import Image
img = Image.open(basefile)
layer = Image.open(layerfile) # this file is the transparent one
print layer.mode # RGBA
img.paste(layer, (xoff, yoff)) # xoff and yoff are 0 in my tests
img.save(outfile)

I think what you want to use is the paste mask argument.
see the docs, (scroll down to paste)
from PIL import Image
img = Image.open(basefile)
layer = Image.open(layerfile) # this file is the transparent one
print layer.mode # RGBA
img.paste(layer, (xoff, yoff), mask=layer)
# the transparancy layer will be used as the mask
img.save(outfile)

Python PIL: How to FIll a Image with a copyright logo like this?

I need to protect my photos by filling them with copyright logos. My OS is Ubuntu 10.10 and Python 2.6. I intend to use PIL.
Supposed I have a copyright logo like this (You can do this in Photoshop easily):
and a picture like this:
I want to use PIL to get copyrighted pictures like the following (Fill the original pic with pattern):
and Final Result by altering the opacity of logos:
Is there any function in PIL that can do this? Any hint?
Thanks a lot!

PIL is certainly capable of this. First you'll want to create an image that contains the repeated text. It should be, oh, maybe twice the size of the image you want to watermark (since you'll need to rotate it and then crop it). You can use Image.new() to create such an image, then ImageDraw.Draw.text() in a loop to repeatedly plaster your text onto it, and the image's rotate() method to rotate it 15 degrees or so. Then crop it to the size of the original image using the crop() method of the image.
To combine it first you'll want to use ImageChops.multiply() to superimpose the watermark onto a copy of the original image (which will have it at 100% opacity) then ImageChops.blend() to blend the watermarked copy with the original image at the desired opacity.
That should give you enough information to get going -- if you run into a roadblock, post code showing what you've got so far, and ask a specific question about what you're having difficulty with.

Just a sample：
#!/usr/bin/python
# -*- coding: utf-8 -*-
from PIL import Image
def fill_watermark():
im = Image.open('a.jpg').convert('RGBA')
bg = Image.new(mode='RGBA', size=im.size, color=(255, 255, 255, 0))
logo = Image.open('logo.png') # .rotate(45) if you want, bg transparent
bw, bh = im.size
iw, ih = logo.size
for j in range(bh // ih):
for i in range(bw // iw):
bg.paste(logo, (i * iw, j * ih))
im.alpha_composite(bg)
im.show()
fill_watermark()