Re: [Image-SIG] Group4 Tiff Decoder?
On approximately 5/20/2009 5:34 AM, came the following characters from the keyboard of Fredrik Lundh: On Tue, May 19, 2009 at 9:52 PM, Greg Taylor wrote: Googling around, I keep seeing mention over the years that PIL has no Group4 tiff decoder. I saw mention of a patch for PIL 1.1.4, but it doesn't look like this ever made it into upstream. Perhaps I haven't dug deep enough, but can anyone enlighten me to what the situation is currently with Group4 Tiff decoding? I'd love to be able to use PIL for some mission critical stuff at work, but this is a show-stopper due to our setup. The patch depended on too many libtiff internals for me to feel confident that it was a good idea to add it to PIL's standard distribution; So if a patch were produced that depended only on published libtiff APIs, would it be likely to be accepted? I'm not sure I'm capable of producing such a patch, unfortunately, because I've never looked at PIL internals, and I've shuddered every time I've looked at libtiff APIs... but if it would be considered a useful addition to PIL, perhaps someone would, or perhaps someday I would. I mean, it would certainly be useful to me, but there is no point in thinking further along this line if it is already known that the any TIFF G4 patch would be rejected because of some negative perspective regarding the utility of adding support for G4 to PIL. there are a few other bindings, but none that feels complete enough. I don't understand this remark. What are the other bindings, and what feels incomplete about them? Were someone to want to follow up, to produce a PIL-G4 capability, to see if it would be better to start from scratch, or start from one of these bindings, it would be good to better understand these "feelings". In addition to the solution already posted, you can use "tiffcp -c none -r -1 %s %s" % (myfilename, tempfilename) to unpack to a temporary file; this is fairly efficient since PIL can then memory map the resulting image file. The tiffcp utility is shipped with libtiff. This solution seems to produce a way to read TIFF G4 files, but not to write them; clearly one could write a temporary TIFF, and then construct a tiffcp command to compress it. But does that then mean shipping tiffcp with the application, or depending on its separate installation and being able to find it from the application? If so, that is somewhat cumbersome, and error prone. Also, it adds a requirement for extra disk storage, since the compressed files are quite small compared to the uncompressed files... I'm not sure I can endorse the "fairly efficient" comment, because of the need to write the large uncompressed files to disk, if using such a technique. Of course, for small files (a few letter size pages at 300-600 dpi), one at a time, it is not noticeable compared to user interaction, but when doing batch processing of book files containing hundreds of pages, it is definitely noticeable. I'm presently using this sort of technique, but only for my own use on my own computer, and using ImageMagick which is probably less efficient than using tiffcp (but since ImageMagick has a decent Perl API, and I'm coming from that background, in Perl I could use ImageMagick APIs rather than file manipulations via the command line and the system API). From Python, I should likely convert to using tiffcp for these conversions, for a bit of increased performance, but that doesn't solve the cumbersome API nor the temporary file issues. -- Glenn -- http://nevcal.com/ === A protocol is complete when there is nothing left to remove. -- Stuart Cheshire, Apple Computer, regarding Zero Configuration Networking ___ Image-SIG maillist - Image-SIG@python.org http://mail.python.org/mailman/listinfo/image-sig
Re: [Image-SIG] Group4 Tiff Decoder?
On Tue, May 19, 2009 at 9:52 PM, Greg Taylor wrote: > Googling around, I keep seeing mention over the years that PIL has no Group4 > tiff decoder. I saw mention of a patch for PIL 1.1.4, but it doesn't look > like this ever made it into upstream. Perhaps I haven't dug deep enough, but > can anyone enlighten me to what the situation is currently with Group4 Tiff > decoding? I'd love to be able to use PIL for some mission critical stuff at > work, but this is a show-stopper due to our setup. The patch depended on too many libtiff internals for me to feel confident that it was a good idea to add it to PIL's standard distribution; there are a few other bindings, but none that feels complete enough. In addition to the solution already posted, you can use "tiffcp -c none -r -1 %s %s" % (myfilename, tempfilename) to unpack to a temporary file; this is fairly efficient since PIL can then memory map the resulting image file. The tiffcp utility is shipped with libtiff. ___ Image-SIG maillist - Image-SIG@python.org http://mail.python.org/mailman/listinfo/image-sig
Re: [Image-SIG] Group4 Tiff Decoder?
Glenn Linderman wrote: but can anyone enlighten me to what the situation is currently with Group4 Tiff decoding? I'd love to be able to use PIL for some mission critical stuff at work, but this is a show-stopper due to our setup. Some times ago I develop freeimagepy due to this PIL "limitation" for a my fax python project and release it, so you can use it for load transform it into a pil image: import FreeImagePy as FIPY F = FIPY.Image() F.load(imagePath) pil =F.convertToPil() It's not so well developed as I would, but do its work! Michele ___ Image-SIG maillist - Image-SIG@python.org http://mail.python.org/mailman/listinfo/image-sig
Re: [Image-SIG] Group4 Tiff Decoder?
On approximately 5/19/2009 12:52 PM, came the following characters from the keyboard of Greg Taylor: Hello all, Googling around, I keep seeing mention over the years that PIL has no Group4 tiff decoder. I saw mention of a patch for PIL 1.1.4, but it doesn't look like this ever made it into upstream. Perhaps I haven't dug deep enough, but can anyone enlighten me to what the situation is currently with Group4 Tiff decoding? I'd love to be able to use PIL for some mission critical stuff at work, but this is a show-stopper due to our setup. I'm currently using command-line ImageMagick and (when on Windows) command-line IrfanView (which is way faster than ImageMagick for Group4 TIFF filse) because PIL doesn't do Group4 decoding or encoding, and because the wrapper for direct use of TIFF lib is arcane (which is no surprise, because TIFF lib's API is arcane to start with). What I would dearly like is a simple API that would read a Group4 TIFF and convert it to an array of memory bitmaps (one per internal image) in a format (a PIL format, or otherwise) that could be manipulated, and preferably each array entry converted to/from QtImage format, and another API that writes it back out in Group4 TIFF format. David Boddie provided a source Qt image extension of some sort some time back that might do the job, Qt-wise, at least for a single page file, but I haven't had time to figure out how to compile my own versions of Qt, PyQt, SIP, etc., to figure out how to make that work, nor to figure out if it handles multiple page images. So, this awaits someone providing it, or a large rasher of tuits provided, for me to figure out the TIFF lib API and code it myself. -- Glenn “Everyone is entitled to their own opinion, but not their own facts. In turn, everyone is entitled to their own opinions of the facts, but not their own facts based on their opinions.” -- Guy Rocha, retiring NV state archivist ___ Image-SIG maillist - Image-SIG@python.org http://mail.python.org/mailman/listinfo/image-sig
[Image-SIG] Group4 Tiff Decoder?
Hello all, Googling around, I keep seeing mention over the years that PIL has no Group4 tiff decoder. I saw mention of a patch for PIL 1.1.4, but it doesn't look like this ever made it into upstream. Perhaps I haven't dug deep enough, but can anyone enlighten me to what the situation is currently with Group4 Tiff decoding? I'd love to be able to use PIL for some mission critical stuff at work, but this is a show-stopper due to our setup. Thanks in advance, Greg -- Greg Taylor Clemson University, Class of 2009 Cell: (864) 888-7964 http://gc-taylor.com ___ Image-SIG maillist - Image-SIG@python.org http://mail.python.org/mailman/listinfo/image-sig
