From: Tim Hunter <TimHunter@...>
Date: 2008-02-04T10:29:50+09:00
Subject: Re: Resizing pictures for file size

David Moreno wrote:
> On Mon, 2008-02-04 at 08:34 +0900, Tim Hunter wrote:
>> J. Pablo Fern�ndez wrote:
>>> Hello,
>>>
>>> I'm using rmagick but I'm open to other libraries if needed. I want to
>>> resize an image, scale actually (mantaining the aspect ratio) so that
>>> the
>>> size of the file is lower than a certain amount of bytes. Any ideas
>>> how to
>>> do this?
>>>
>>> Thanks.
>>> --
>>> J. Pablo Fern�ndez <pupeno@pupeno.com> (http://pupeno.com)
>>>
>> I can't speak for other libraries, but this is not possible with 
>> RMagick. This question comes up from time-to-time on the ImageMagick 
>> forum but the answer is always "not possible" other than just by 
>> trial-and-error.
> 
> What exactly is not possible? Resize according to the certain amount of
> bytes after the resize?
> 

There is no method in RMagick that takes an image and a file size in 
bytes and returns an image that, when saved to a file, produces a file 
close to or no larger than the specified size. The file size depends on 
the image format, the compression level, and the image itself.

-- 
RMagick: http://rmagick.rubyforge.org/
RMagick 2: http://rmagick.rubyforge.org/rmagick2.html