Bug#758487: findimagedupes: speed improvements

[Alex 'AdUser' Z]

Package: findimagedupes
Version: 2.18
Severity: wishlist
Tags: patch upstream

Hi all!

I want to offer the patch, significantly improves speed of image sampling.
It's very simple: near line 483 replace 'Modulate' call with 'Quantize'.

>From the manpage:
==============
3) Grayscale by reducing saturation.
==============

Original line:
> try $image->Modulate(saturation=>-100);

New line:
> try $image->Quantize(colorspace => 'gray');

'Quantize' works 2.5x times faster according to my benchmarks.

Patch against version 2.18 in attachment. Thanks.

-- System Information:
Debian Release: 7.6
  APT prefers stable-updates
  APT policy: (500, 'stable-updates'), (500, 'stable')
Architecture: amd64 (x86_64)

Kernel: Linux 3.2.0-4-amd64 (SMP w/8 CPU cores)
Locale: LANG=ru_RU.UTF-8, LC_CTYPE=ru_RU.UTF-8 (charmap=UTF-8)
Shell: /bin/sh linked to /bin/dash

Versions of packages findimagedupes depends on:
ii  libc6                       2.13-38+deb7u3
ii  libfile-mimeinfo-perl       0.16-1
ii  libgraphics-magick-perl     1.3.16-1.1
pn  libinline-perl              <none>
ii  perl                        5.14.2-21+deb7u1
ii  perl-base [perlapi-5.14.2]  5.14.2-21+deb7u1

findimagedupes recommends no packages.

findimagedupes suggests no packages.
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