pct2rgb fails when palette/RAT has >256 entries

[Robert Coup]

When running pct2rgb against an image having a colour table with >256 entries, it dies. The lookup array built from the colour table is built as max(256, len(colourTable)) rather than min(256, len(colourTable)), so lookups for entries after 256 fail:

$ pct2rgb -rgba rat.img test_pct2rgb_4.tif
  File "pct2rgb.py", line 167, in <module>
    dst_data = Numeric.take(band_lookup,src_data)
  File "/usr/lib/python2.7/dist-packages/numpy/core/fromnumeric.py", line 103, in take
    return take(indices, axis, out, mode)
IndexError: index out of range for array

I've attached a patch, test case, and am sourcing licensing release for the image used in the test case.

[Robert Coup]

Patch & test case

[Even Rouault]

I've applied the patch to pct2rgb.py in r25674 (but not the new test case since the source image is missing)

[Robert Coup]

Added the test case in r25688.

The test data (trunk/autotest/gcore/data/rat.img​) is from Land Environments New Zealand (LENZ) Level 2 - CC-BY Licensed by Ministry for the Environment. ERDAS Imagine conversion & processing by Landcare Research. Release for GDAL's test suite explicitly cleared.