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Write TIFF file in python from String

I need a way to easily write a compressed TIFF file from a String in python. I already look at the Python Imaging Library PIL But I need to write a very specific TIFF format and PIL only supports uncompressed at the moment. I开发者_如何学编程 need to write a LZW compressed, striped TIFF with just one simple line of text in it. I would rather not have to write something from scratch, but if I do I do.


I have just used WinPython to write a TIFF file with LZW compression:

from PIL import Image, TiffImagePlugin

[...]

TiffImagePlugin.WRITE_LIBTIFF = True
im.save(filename, compression = "tiff_lzw")
TiffImagePlugin.WRITE_LIBTIFF = False

(See this WinPython ticket).

(Edit 2014-05-13: Fixed my READ_LIBTIFF/WRITE_LIBTIFF confusion).

(Edit 2015-02-23: Updated the WinPython link).


I've used this code in the past, so I can say that it works. This script is from 1997, and PIL has yet to implement compressed TIFF writing.

# 
# use "tiffcp" to write compressed TIFF files.
#
# fredrik lundh (may 13, 1997)
#

import os, tempfile

# install standard driver
import Image, TiffImagePlugin 

LZW      = "lzw"
ZIP      = "zip"
JPEG     = "jpeg"
PACKBITS = "packbits"
G3       = "g3"
G4       = "g4"

def _save(im, fp, filename):

    # check compression mode
    try:
    compression = im.encoderinfo["compression"]
    except KeyError:
    # use standard driver
    TiffImagePlugin._save(im, fp, filename)
    else:
    # compress via temporary file
    if compression not in (LZW, ZIP, JPEG, PACKBITS, G3, G4):
        raise IOError, "unknown compression mode"
    file = tempfile.mktemp()
    im.save(file, "TIFF")
    os.system("tiffcp -c %s %s %s" % (compression, file, filename))
    try: os.unlink(file)
    except: pass

Image.register_save(TiffImagePlugin.TiffImageFile.format, _save)

if __name__ == "__main__":
    # test
    im = Image.open("/usr/iv/tip/images/lenna.ppm")
    im = im.point(lambda v: v >= 128 and 255, "1")
    im.save("lenna.tif", compression=G4)

This code (afaict) just adds the ability to write compressed TIFFs using the standard PIL library, so if you've written your text to a PIL Image object, it should be really easy to implement.

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