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Date: Wed, 25 Mar 2015 16:05:05 +1100
Subject: Re: Newbie looking for elegant solution
From: Chris Angelico <rosuav@gmail.com>
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On Wed, Mar 25, 2015 at 3:46 PM,  <kai.peters@gmail.com> wrote:
> Now I have just read the latest spec and speed/memory may become issues:
>
> 1 bit images of a size of 1024 x 1280 need to be processed this way, so
> 1310720 list elements. Also needs to be 2.7 only.
>
> Any recommendations?

2.7 only? Then my solution won't work (I just tried to port it, and
integers don't have to_bytes). Paul's solution works. Here's an
alternative:

>>> import numpy
>>> list(numpy.packbits(numpy.array(l),-1))
[177, 105, 117]

Of course, this does mean installing numpy. It is crushing the nut
with the triphammer - an absurd extravagance of energy, but the nut is
effectively crushed all the same.

ChrisA