# Bitmap manipulation

**URL:** <https://www.ruby-forum.com/t/bitmap-manipulation/85823>\
**Category:** Ruby\
**Created:** [February 16, 2007, 4:47pm UTC](https://www.ruby-forum.com/t/bitmap-manipulation/85823 "2007-02-16T16:47:18Z")\
**Posts on this page:** 8\
**Page:** 1

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**Author:** ![jimb](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/j/f4b2a3/32.png) [@jimb](https://www.ruby-forum.com/u/jimb)\
**Post date:** [February 16, 2007, 4:47pm UTC](https://www.ruby-forum.com/t/bitmap-manipulation/85823/1 "2007-02-16T16:47:18Z")

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I would normally use FreeImage, but I cannot find a Ruby wrapper for  
this?

So if I can’t find a wrapper for FreeImage is there any other suitable  
libraries that I can use with Ruby?

Thanks,  
Jim.

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<div class="post-metadata">

**Author:** ![jimb](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/j/f4b2a3/32.png) [@jimb](https://www.ruby-forum.com/u/jimb)\
**Post date:** [February 16, 2007, 4:53pm UTC](https://www.ruby-forum.com/t/bitmap-manipulation/85823/2 "2007-02-16T16:53:24Z")

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On 2/16/07, Jim B. [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) wrote:

> I would normally use FreeImage, but I cannot find a Ruby wrapper for  
> this?
> 
> So if I can’t find a wrapper for FreeImage is there any other suitable  
> libraries that I can use with Ruby?
> 
> Thanks,  
> Jim.

[http://seattlerb.rubyforge.org/ImageScience.html](http://seattlerb.rubyforge.org/ImageScience.html)

appears to wrap FreeImage.

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<div class="post-metadata">

**Author:** ![jimb](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/j/f4b2a3/32.png) [@jimb](https://www.ruby-forum.com/u/jimb)\
**Post date:** [February 16, 2007, 4:53pm UTC](https://www.ruby-forum.com/t/bitmap-manipulation/85823/3 "2007-02-16T16:53:26Z")

</div>

Jim B. wrote:

> I would normally use FreeImage, but I cannot find a Ruby wrapper for  
> this?
> 
> So if I can’t find a wrapper for FreeImage is there any other suitable  
> libraries that I can use with Ruby?
> 
> Thanks,  
> Jim.

[http://seattlerb.rubyforge.org/ImageScience.html](http://seattlerb.rubyforge.org/ImageScience.html)

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<div class="post-metadata">

**Author:** ![jimb](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/j/f4b2a3/32.png) [@jimb](https://www.ruby-forum.com/u/jimb)\
**Post date:** [February 16, 2007, 5:18pm UTC](https://www.ruby-forum.com/t/bitmap-manipulation/85823/4 "2007-02-16T17:18:37Z")

</div>

No ImageScience uses Free Image but does not expose much of it, it  
appears to be a simple lib for creating thumbnails.

Thanks,  
Jim.

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<div class="post-metadata">

**Author:** ![jimb](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/j/f4b2a3/32.png) [@jimb](https://www.ruby-forum.com/u/jimb)\
**Post date:** [February 16, 2007, 5:45pm UTC](https://www.ruby-forum.com/t/bitmap-manipulation/85823/5 "2007-02-16T17:45:34Z")

</div>

On 2/16/07, Jim B. [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) wrote:

> No ImageScience uses Free Image but does not expose much of it, it  
> appears to be a simple lib for creating thumbnails.
> 
> Thanks,  
> Jim.

If you have ImageMagick or GraphicsMagick available, RMagick…  
[http://rmagick.rubyforge.org/](http://rmagick.rubyforge.org/)

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<div class="post-metadata">

**Author:** ![jimb](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/j/f4b2a3/32.png) [@jimb](https://www.ruby-forum.com/u/jimb)\
**Post date:** [February 16, 2007, 5:46pm UTC](https://www.ruby-forum.com/t/bitmap-manipulation/85823/6 "2007-02-16T17:46:35Z")

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have u tried RMagick ?

i found it very useful, a lots of functionality easy to implement.

Thumbnail can be made really easily with RMagick.

I am using RMagick in my rails based captcha plugin SimpleCaptcha(  
[http://expressica.com/2007/02/06/simple-captcha-released-the-captcha-for-rails-applications/](http://expressica.com/2007/02/06/simple-captcha-released-the-captcha-for-rails-applications/))  
and its working absolutely fine.

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<div class="post-metadata">

**Author:** ![jimb](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/j/f4b2a3/32.png) [@jimb](https://www.ruby-forum.com/u/jimb)\
**Post date:** [February 16, 2007, 5:57pm UTC](https://www.ruby-forum.com/t/bitmap-manipulation/85823/7 "2007-02-16T17:57:58Z")

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Rmagic looks like it will work a treat.

Many thanks again,  
Jim.

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<div class="post-metadata">

**Author:** ![jimb](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/j/f4b2a3/32.png) [@jimb](https://www.ruby-forum.com/u/jimb)\
**Post date:** [February 16, 2007, 6:05pm UTC](https://www.ruby-forum.com/t/bitmap-manipulation/85823/8 "2007-02-16T18:05:36Z")

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example to generate THUMBNAIL using RMagick

======================================  
require ‘RMagick’  
include Magick

img = Image.read(“image/path/my\_image.jpg”).first  
thumb\_img = img.thumbnail(50, 50)

thumb\_img.write(“image/path/my\_image\_thuumb.jpg”)

=======================================  
check out more details here  
[http://www.simplesystems.org/RMagick/doc/image3.html#thumbnail](http://www.simplesystems.org/RMagick/doc/image3.html#thumbnail)