[reportlab-users] Still confused about PIL Image objects

[Ian Sparks]

Thanks Sam, that's a good tip. I made it a bit more efficient :

            writeSIO = StringIO.StringIO()
            im.save(writeSIO, format="JPEG")
            writeSIO.seek(0) #Rewind it
            ir = ImageReader(writeSIO)
            canvas.drawImage(ir, ....)

I actually read my image from a Base64 encoded XML element, push it into a StringIO stream, read that into the PIL Image() constructor to modify the image, now I'm going to stream it out again to push it into the PDF. Better than the interim file I have at least... so thanks!



> -----Original Message-----
> From: Sam Hunter [mailto:shunter at dbsupply.com]
> Sent: Wednesday, May 11, 2005 12:10 PM
> To: Support list for users of Reportlab software
> Subject: Re: [reportlab-users] Still confused about PIL Image objects
> 
> 
> Hey Ian, I had the same problem and it was a serious pain.  I finally 
> just re-wrote some of the Reportlab code so that it could handle PIL 
> images passed directly into the canvas.drawImage() function.  
> I can send 
> you the three files I had to change if you like. 
> 
> The other option is to use StringIO, save the PIL image to a StringIO 
> object, and then pass that in to canvas.drawImage() or make an 
> ImageReader object with it.  I forget which works in the non-modified 
> version.  The funny part about all of this is that if you are using 
> ImageReader it defaults to opening anything without a JPEG extension 
> with PIL, and the comments in the JPEG code suggest that PIL 
> should be 
> used for that too.
> 
> StringIO is kinda funny..  as far as I can tell, you can 
> create either a 
> readable, or a writable object, but one object doesn't seem 
> to do both?  
> Perhaps I'm confused here....  But I think the code below should work.
> 
> Sam
> 
> The StringIO option goes something like this:
> #----------------------------------
> Im = Image.open("imagefile.jpg")
> #do some operations on the image......
> 
> #then convert to a StringIO object
> 
> from cStringIO import StringIO  # "cStringIO" is faster, but 
> if you need 
> to subclass, use "StringIO"
> writeSIO = StringIO()  #create an empty writeable StringIO object
> 
> Im.save(writeSIO, format="JPEG")
> 
> readSIO = writeSIO.getvalue()   #create a readable StringIO object
> 
> ir = ImageReader(readSIO)
> 
> canvas.drawImage(ir, x, y, xsize, ysize)
> #----------------------------------
> 
> 
> Ian Sparks wrote:
> 
> >It used to be that PIL Image objects could be passed to the 
> canvas.drawImage() method. Then there was a change in 
> ReportLab which made this fail with an error related to 
> "getRGBData()".
> >
> >I understand that this was done to reduce the requirement to 
> have PIL installed. Fair enough.
> >
> >I'm using reportlab 1.20. I have a PIL Image object that I 
> want to pass to canvas.drawImage(). I'm using PIL because I 
> often need to resize or modify the image in some way before I 
> write it into the PDF.
> >
> >Right now I'm doing this :
> >
> >		#im is the PIL Image object
> >		
> >            filename = 'temp_im.bmp'
> >            im.save(filename) #This is an annoying hack, 
> save to a file to get it re-imported  
> >            canvas.drawImage(filename,....)
> >            os.remove(filename) #Remove it again
> >
> >There has to be a better way. Someone please enlighten me?
> >_______________________________________________
> >reportlab-users mailing list
> >reportlab-users at reportlab.com
> >http://two.pairlist.net/mailman/listinfo/reportlab-users
> >
> >  
> >
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