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From: Nobody <nobody@nowhere.com>
Subject: Re: Image processing to auto adjust colors in python ?
Date: Mon, 16 May 2011 19:02:08 +0100
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On Mon, 16 May 2011 10:11:43 -0700, goldtech wrote:

> I'm processing thumbnails with python but one thing I need to do is to
> auto-adjust an image for the "best" colors. I am using ffmpeg to get
> thumbs three seconds into a video, sometimes  the image is too dark.
> Normally I'd go into something like the windows program Irfan View and
> do "Auto Adjust Colors", but I need a comand-line solution to
> processes hundreds of images in a loop. I'm using Ubuntu and Python.
> Is there an image precessing package i could use to do this?

PIL (Python Imaging Library) is the most widely-used general-purpose image
library. For more advanced tasks, the usual solution is to use PIL to
load/save images and do the processing with NumPy/SciPy (array-processing
library).

But you might want to check whether either ImageMagick (e.g. "convert
-equalize ...") or NetPBM (e.g. pnmhisteq) do what you want. If they do,
it will probably be the simplest solution.