Python Wand convert PDF to PNG disable transparent (alpha_channel)

python wand image
python convert pdf to png
python wand image size
wand image alpha channel
install wand python
ghostscript python pdf to image
python wand flatten
python wand format

I'm trying to convert a PDF to PNG - this all works fine, however, the output image is still transparent even when I believe I have disabled it:

with Image(filename='sample.pdf', resolution=300) as img:
    img.background_color = Color("white")
    img.alpha_channel = False
    img.save(filename='image.png')

The above produces the images but are transparent, I also tried the below:

with Image(filename='sample.pdf', resolution=300, background=Color('white')) as img:
    img.alpha_channel = False
    img.save(filename='image.png')

which produces this error:

Traceback (most recent call last):
  File "file_convert.py", line 20, in <module>
    with Image(filename='sample.pdf', resolution=300, background=Color('white')) as img:
  File "/Users/Frank/.virtualenvs/wand/lib/python2.7/site-packages/wand/image.py", line 1943, in __init__
    raise TypeError("blank image parameters can't be used with image "
TypeError: blank image parameters can't be used with image opening parameters

I also had some PDFs to convert to PNG. This worked for me and seems simpler than compositing images, as shown above.:

all_pages = Image(blob=self.pdf)        # PDF will have several pages.
single_image = all_pages.sequence[0]    # Just work on first page
with Image(single_image) as i:
    i.format = 'png'
    i.background_color = Color('white') # Set white background.
    i.alpha_channel = 'remove'          # Remove transparency and replace with bg.

Reference: wand.image

Python Wand convert PDF to PNG disable transparent, I'm trying to convert a PDF to PNG - this all works fine, however, the output image is Python Wand convert PDF to PNG disable transparent (alpha_channel). I need to create thumbnails of pdf files, and I am using Imagemagick to achieve that. I have tried Pythonmagick and wand to convert the pdf to an image. However, when I try to resize the converte


From a previous answer, try creating an empty image with a background color, then composite over.

from wand.image import Image
from wand.color import Color

with Image(filename="sample.pdf", resolution=300) as img:
  with Image(width=img.width, height=img.height, background=Color("white")) as bg:
    bg.composite(img,0,0)
    bg.save(filename="image.png")

Python Magickwand pdf to image converting and resize the image, ref: Python Wand convert PDF to PNG disable transparent (alpha_channel). Efficient Image Resizing With ImageMagick, This says that we want ImageMagick's� To remove image alpha channel, we can use ImageMagick application. However, this way is hard to use in python application. In this tutorial, we will introduce how to detect and remove image alpha channel in python application.


Compiling the other answers, here is the function I use to convert a PDF into pages:

import os
from wand.image import Image
from wand.color import Color


def convert_pdf(filename, output_path, resolution=150):
    """ Convert a PDF into images.

        All the pages will give a single png file with format:
        {pdf_filename}-{page_number}.png

        The function removes the alpha channel from the image and
        replace it with a white background.
    """
    all_pages = Image(filename=filename, resolution=resolution)
    for i, page in enumerate(all_pages.sequence):
        with Image(page) as img:
            img.format = 'png'
            img.background_color = Color('white')
            img.alpha_channel = 'remove'

            image_filename = os.path.splitext(os.path.basename(filename))[0]
            image_filename = '{}-{}.png'.format(image_filename, i)
            image_filename = os.path.join(output_path, image_filename)

            img.save(filename=image_filename)

wand.image — Image objects — Wand 0.4.1, with Image(filename='pikachu.png') as i: print('width =', i.width) print('height =', i. height) of combining images that have, or do not have, transparency or an alpha channel. It can also be used to enable/disable alpha channel, but with different behavior new, Changed in version 0.3.9: Added 'pdf:use-cropbox' option. class wand.image.BaseImage(wand)¶ The abstract base of Image (container) and SingleImage. That means the most of operations, defined in this abstract classs, are possible for both Image and SingleImage. New in version 0.3.0. alpha_channel¶ (bool) Get state of image alpha channel. It can also be used to enable/disable alpha channel. New in


The other answer (compositing with a white image) works, but only on the last page, as does setting the alpha channel directly. The following works on wand 0.4.2:

im = wand_image(filename='/tmp/foo.pdf', resolution=200)
for i, page in enumerate(im.sequence):
    with wand_image(page) as page_image:
        page_image.alpha_channel = False
        page_image.save(filename='/tmp/foo.pdf.images/page-%s.png' % i)

I think this is probably a bug in wand. It seems like setting the alpha channel for a PDF should affect all pages, but it doesn't.

wand.image — Image objects — Wand 0.5.7, with Image(filename='pikachu.png') as i: print('width =', i.width) print('height =', i. height) 'set'; 'shape'; 'transparent'; 'flatten' - Only available in ImageMagick-6; ' remove' It can also be used to enable/disable alpha channel, but with different Which would translate RGB color channels by calculating the following:. alpha_channel¶ (bool) Get state of image alpha channel. It can also be used to enable/disable alpha channel, but with different behavior new, copied, or existing. Behavior of setting alpha_channel is defined with the following values: 'activate', 'on', or True will enable an images alpha channel. Existing alpha data is preserved.


For those who are still having problem with this, I found solution (it works in version 0.4.1 and above, I am not sure about earlier versions). So you should just use something like this:

from wand.image import Image
from wand.color import Color


with Image(filename='sample.pdf', resolution=300) as img:
img.background_color = Color("white")
img.alpha_channel = 'remove'
img.save(filename='image.png')

Allow Lossy PDF (#54) � Issues � josch / img2pdf � GitLab, Image contains transparency which cannot be retained in PDF. img2pdf will not You can remove the alpha channel using imagemagick: $ convert input.png� Even before using wand, it might be helpful to convert the PDF using the command line tool, just to verify that the installation is correct and the PDF you are using is working. Here is a command to extract the images from a PDF: convert -density 300 source.pdf s.png This will create a single png for each page of the source.pdf file.


python — Python Wand convert PDF a PNG deshabilitar , Python Wand convert PDF a PNG deshabilitar transparente (alpha_channel) background. i.alpha_channel = 'remove' # Remove transparency and replace� Image module of the Python image processing library Pillow (PIL) provides putalpha() for adding an alpha channel to an image.Image Module — Pillow (PIL Fork) 4.4.0.dev0 documentation Here, the following contents will be described.How to use Image.putalpha() Set uniform transparency over the entire


barcode_example_generator.py � master � Works on my machine , import canvas from wand.image import Image from wand.color import / python-wand-convert-pdf-to-png-disable-transparent-alpha-channel� Wand is a ctypes-based simple ImageMagick binding for Python. from wand.image import Image from wand.display import display with Image ( filename = 'mona-lisa.png' ) as img : print ( img . size ) for r in 1 , 2 , 3 : with img . clone () as i : i . resize ( int ( i . width * r * 0.25 ), int ( i . height * r * 0.25 )) i . rotate ( 90 * r ) i


[PDF] Wand Documentation, Wand is a Python binding of ImageMagick, so you have to install it as well: • Debian/ result like convert() or slicing operator. So the img.save(filename=' 200x100-transparent.png') with Image(filename='document.pdf[0]') as first_page: It can also be used to enable/disable alpha channel, but with. The following are 40 code examples for showing how to use wand.image.Image().These examples are extracted from open source projects. You can vote up the ones you like or vote down the ones you don't like, and go to the original project or source file by following the links above each example.