在MacOS上使用Python将PDF图像转换为PNG

Question

I have read a lot of articles that try to describe how to convert PDF's to a PNG image. But I simply cannot get it working. I tried to import PythonMagick on top of my script but it returns the error ImportError: No module named PythonMagick .

Is it possible to install PythonMagick as easy as shell tools via Homebrew?! The background is my Python script, which is much shorter than the equivalent Bash script. The only thing that is not working is the PDF to PNG conversion and scaling of the final image. In Bash, I use Imagemagick for this, but I want to do this in Python too, since it is a one liner.

Any Ideas?

EDIT

The code can be found on Github: https://github.com/Blackjacx/Scripts/blob/master/iconizer.py

SOLUTION FOUND

Using MagickWand works better so I am using this. To install it I did:

$ brew install imagemagick@6
$ export MAGICK_HOME=/usr/local/opt/imagemagick@6

Answer 1

Try this for the error ImportError: No module named PythonMagick

Also have a look at this link

Try changing: from . import _PythonMagick to import _PythonMagick in you init .py of PythonMagick

Answer 2

I don't recommend you to use imagemagick . Because this tools render output by pixels but not vectors inside the pdf file. So if your pdf file's original resolution is much lower than the resolution of your output png file, it will be a quality loss.

Try to use mupdf . The command mudraw you should use is various decided by version. Most of time it should be:

mudraw [-h 1080] [-w 1080] [-o <output_path>] <input_path> 

This tool could manipulate vectors so there won't be any quality loss not matter how you zoom your original file.

Answer 3

You can use Apple's own CoreGraphics APIs with a python script, "out of the box". The following script will convert PDF files, supplied as arguments, to PNG. It can also be used in Automator's "Run Shell Script" action.

#!/usr/bin/python
# coding: utf-8

import os, sys
import Quartz as Quartz
from LaunchServices import (kUTTypeJPEG, kUTTypeTIFF, kUTTypePNG, kCFAllocatorDefault) 

resolution = 300.0 #dpi
scale = resolution/72.0

cs = Quartz.CGColorSpaceCreateWithName(Quartz.kCGColorSpaceSRGB)
whiteColor = Quartz.CGColorCreate(cs, (1, 1, 1, 1))
# Options: kCGImageAlphaNoneSkipLast (no trans), kCGImageAlphaPremultipliedLast 
transparency = Quartz.kCGImageAlphaNoneSkipLast

#Save image to file
def writeImage (image, url, type, options):
    destination = Quartz.CGImageDestinationCreateWithURL(url, type, 1, None)
    Quartz.CGImageDestinationAddImage(destination, image, options)
    Quartz.CGImageDestinationFinalize(destination)
    return

def getFilename(filepath):
    i=0
    newName = filepath
    while os.path.exists(newName):
        i += 1
        newName = filepath + " %02d"%i
    return newName

if __name__ == '__main__':

    for filename in sys.argv[1:]:
        pdf = Quartz.CGPDFDocumentCreateWithProvider(Quartz.CGDataProviderCreateWithFilename(filename))
        numPages = Quartz.CGPDFDocumentGetNumberOfPages(pdf)
        shortName = os.path.splitext(filename)[0]
        prefix = os.path.splitext(os.path.basename(filename))[0]
        folderName = getFilename(shortName)
        try:
            os.mkdir(folderName)
        except:
            print "Can't create directory '%s'"%(folderName)
            sys.exit()

        # For each page, create a file
        for i in range (1, numPages+1):
            page = Quartz.CGPDFDocumentGetPage(pdf, i)
            if page:
        #Get mediabox
                mediaBox = Quartz.CGPDFPageGetBoxRect(page, Quartz.kCGPDFMediaBox)
                x = Quartz.CGRectGetWidth(mediaBox)
                y = Quartz.CGRectGetHeight(mediaBox)
                x *= scale
                y *= scale
                r = Quartz.CGRectMake(0,0,x, y)
        # Create a Bitmap Context, draw a white background and add the PDF
                writeContext = Quartz.CGBitmapContextCreate(None, int(x), int(y), 8, 0, cs, transparency)
                Quartz.CGContextSaveGState (writeContext)
                Quartz.CGContextScaleCTM(writeContext, scale,scale)
                Quartz.CGContextSetFillColorWithColor(writeContext, whiteColor)
                Quartz.CGContextFillRect(writeContext, r)
                Quartz.CGContextDrawPDFPage(writeContext, page)
                Quartz.CGContextRestoreGState(writeContext)
        # Convert to an "Image"
                image = Quartz.CGBitmapContextCreateImage(writeContext) 
        # Create unique filename per page
                outFile = folderName +"/" + prefix + " %03d.png"%i
                url = Quartz.CFURLCreateFromFileSystemRepresentation(kCFAllocatorDefault, outFile, len(outFile), False)
        # kUTTypeJPEG, kUTTypeTIFF, kUTTypePNG
                type = kUTTypePNG
        # See the full range of image properties on Apple's developer pages.
                options = {
                    Quartz.kCGImagePropertyDPIHeight: resolution,
                    Quartz.kCGImagePropertyDPIWidth: resolution
                    }
                writeImage (image, url, type, options)
                del page