[Image-SIG] Segmentation fault on PIL

[Andres Moreira]

Hi guys, 

 I load a palette image (I've attach it), with 1000 colors, and I want 
 to quantize and dithering it.

 The error is in 

   palette.putpalette(pal)

 Another, question, is this the best way of Quantize an image mapping it
 to that palette and dithering ?

 Thanks a lot! 

 Andres Moreira.
 
 ====
 CODE
 ====

    import Image

    def extract_colour(image, colour_map):
        palette_im = Image.open(colour_map)
        palette_count = len(palette_im.getdata())
        pal = reduce(lambda a,b:a+b, 
                     [(x[1][0],x[1][1],x[1][2]) 
                      for x in palette_im.getcolors(maxcolors=palette_count)])

        # create palette
        palette = Image.new("P", (1,1))
        palette.putpalette(pal)

        im = Image.open(image).convert("RGB").quantize(palette=palette)
        im2 = im.convert("RGBA", dither=Image.FLOYDSTEINBERG)

        return im2.getcolors()

 ==========
 Trace back
 ==========


*** glibc detected *** /usr/bin/python: malloc(): memory corruption: 0x0000000002a5b950 ***
======= Backtrace: =========
/lib/libc.so.6[0x7fc416162fef]
/lib/libc.so.6(__libc_malloc+0x98)[0x7fc416164828]
/usr/bin/python(PyArena_New+0x26)[0x4c1be6]
/usr/bin/python(PyRun_StringFlags+0x3e)[0x4c52fe]
/usr/bin/python[0x49bfe5]
/usr/bin/python(PyEval_EvalFrameEx+0x4e23)[0x4a2b03]
/usr/bin/python(PyEval_EvalFrameEx+0x60ce)[0x4a3dae]
/usr/bin/python(PyEval_EvalCodeEx+0x869)[0x4a4649]
/usr/bin/python[0x5329ad]
/usr/bin/python(PyObject_Call+0x5d)[0x41d3bd]
/usr/bin/python[0x424f48]
/usr/bin/python(PyObject_Call+0x5d)[0x41d3bd]
/usr/bin/python(PyEval_CallObjectWithKeywords+0x56)[0x49cd46]
/usr/bin/python[0x42b51a]
/usr/bin/python(_PyObject_Str+0x6f)[0x45179f]
/usr/bin/python(PyObject_Str+0x13)[0x451853]
/usr/bin/python[0x45d9da]
/usr/bin/python[0x46bc03]
/usr/bin/python(PyObject_Call+0x5d)[0x41d3bd]
/usr/bin/python(PyEval_EvalFrameEx+0x232f)[0x4a000f]
/usr/bin/python(PyEval_EvalFrameEx+0x60ce)[0x4a3dae]
/usr/bin/python(PyEval_EvalCodeEx+0x869)[0x4a4649]
/usr/bin/python[0x5329ad]
/usr/bin/python(PyObject_Call+0x5d)[0x41d3bd]
/usr/bin/python[0x424f48]
/usr/bin/python(PyObject_Call+0x5d)[0x41d3bd]
/usr/bin/python(PyEval_CallObjectWithKeywords+0x56)[0x49cd46]
/usr/bin/python[0x474efe]
/usr/bin/python(_PyObject_Str+0x6f)[0x45179f]
/usr/bin/python(PyObject_Str+0x13)[0x451853]
/usr/bin/python[0x45d9da]
/usr/bin/python[0x46bc03]
/usr/bin/python(PyObject_Call+0x5d)[0x41d3bd]
/usr/bin/python(PyEval_EvalFrameEx+0x232f)[0x4a000f]
/usr/bin/python(PyEval_EvalCodeEx+0x869)[0x4a4649]
/usr/bin/python[0x532ab4]
/usr/bin/python(PyObject_Call+0x5d)[0x41d3bd]
/usr/bin/python(PyEval_EvalFrameEx+0x3780)[0x4a1460]
/usr/bin/python(PyEval_EvalCodeEx+0x869)[0x4a4649]
/usr/bin/python[0x5329ad]
/usr/bin/python(PyObject_Call+0x5d)[0x41d3bd]
/usr/bin/python[0x424f48]
/usr/bin/python(PyObject_Call+0x5d)[0x41d3bd]
/usr/bin/python[0x425be2]
/usr/bin/python(PyObject_Call+0x5d)[0x41d3bd]
/usr/bin/python(PyEval_EvalFrameEx+0x232f)[0x4a000f]
/usr/bin/python(PyEval_EvalCodeEx+0x869)[0x4a4649]
/usr/bin/python(PyEval_EvalFrameEx+0x4fd0)[0x4a2cb0]
/usr/bin/python(PyEval_EvalCodeEx+0x869)[0x4a4649]
/usr/bin/python(PyEval_EvalFrameEx+0x4fd0)[0x4a2cb0]
/usr/bin/python(PyEval_EvalCodeEx+0x869)[0x4a4649]
/usr/bin/python(PyEval_EvalFrameEx+0x4fd0)[0x4a2cb0]
/usr/bin/python(PyEval_EvalCodeEx+0x869)[0x4a4649]
/usr/bin/python(PyEval_EvalCode+0x32)[0x4a4762]
/usr/bin/python(PyRun_FileExFlags+0x13c)[0x4c4c3c]
/usr/bin/python(PyRun_SimpleFileExFlags+0x1fb)[0x4c4f6b]
/usr/bin/python(Py_Main+0xb9e)[0x4189ce]
/lib/libc.so.6(__libc_start_main+0xe6)[0x7fc4161065a6]
/usr/bin/python[0x417ae9]
======= Memory map: ========
00400000-00616000 r-xp 00000000 08:02 1353694                            /usr/bin/python2.6
00815000-00816000 r--p 00215000 08:02 1353694                            /usr/bin/python2.6
00816000-00876000 rw-p 00216000 08:02 1353694                            /usr/bin/python2.6
00876000-00885000 rw-p 00876000 00:00 0 
02466000-02cd3000 rw-p 02466000 00:00 0                                  [heap]
3c63400000-3c63422000 r-xp 00000000 08:02 1355378                        /usr/lib/libjpeg.so.62.0.0
3c63422000-3c63622000 ---p 00022000 08:02 1355378                        /usr/lib/libjpeg.so.62.0.0
3c63622000-3c63623000 rw-p 00022000 08:02 1355378                        /usr/lib/libjpeg.so.62.0.0
7fc40c000000-7fc40c021000 rw-p 7fc40c000000 00:00 0 
7fc40c021000-7fc410000000 ---p 7fc40c021000 00:00 0 
7fc413ccf000-7fc413ce5000 r-xp 00000000 08:02 63477                      /lib/libgcc_s.so.1
7fc413ce5000-7fc413ee5000 ---p 00016000 08:02 63477                      /lib/libgcc_s.so.1
7fc413ee5000-7fc413ee6000 r--p 00016000 08:02 63477                      /lib/libgcc_s.so.1
7fc413ee6000-7fc413ee7000 rw-p 00017000 08:02 63477                      /lib/libgcc_s.so.1
7fc413ee7000-7fc413f21000 r-xp 00000000 08:02 127451                     /usr/lib/python2.6/dist-packages/PIL/_imaging.so
7fc413f21000-7fc414120000 ---p 0003a000 08:02 127451                     /usr/lib/python2.6/dist-packages/PIL/_imaging.sAborted


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