Top Posts Tagged with #image_magick

Simple Captcha without RMagick

Simple Captcha is as it's name points out is probably the simplest captcha plugin out there. It's a little old and not really updated these days (although there is some SimpleCaptcha3 activity) but still working as expected, at least on Rails 2. Now, I know there's creatures among us developers who don't really prefer RMagick, which is the core brick of the plugin. Some popular image related "magick" plugins give us alternative options, probably the most common RMagick replacement being MiniMagick. Besides the usual reasons against RMagick I do found one crucial to be JRuby compatibility. There's an attempt to fix this called RMagick4J but it seems to be incomplete (at least for simple captcha it did not play correctly). Turns out for captcha generation, MiniMagick ain't an option, it misses support for creating images from scratch which is essential. Fortunately, there's still hope thanks to QuickMagick, well that's about enough magick isn't it ?! Sure is, but it's worth it. QuickMagick mixes the simplicity of MiniMagick with the flexibility of RMagick (and works with JRuby). Enough chit-chat, here's how to enjoy the simplest captcha plugin for Rails without RMagick : embedGist('554959.js'); The updated plugin lives at http://github.com/kares/simple_captcha. UPDATE: The latest plugin version now works on Rails 3.0.0+ !

#rails #image_magick #plugin #simple_captcha #captcha

•18+ Adults Only

Watch Anya Live on Cam

Anya is live and ready to show you everything. Watch her strip, dance, and perform exclusive shows just for you. Interact in real-time and make your fantasies come true.

✓ Live Streaming✓ Interactive Chat✓ Private Shows✓ HD Quality✓ Free Actions

Free to watch • No registration required • HD streaming

ImageMagick: Cropping then Resizing a PNG

I've been working on an image processor class for work, and recently ran into this issue. I thought I would post it up here as normally I need to be quite desperate before I start trawling through email mirrors - hopefully somebody comes across this post first.

If you use ImageMagick (in particular, in conjunction with MiniMagick), then you may come across this issue, and there is actually a quick fix to it. The issue itself is as follows: my image processor retrieves an image from an online source, but the image has a 1 or 2px border, and is thousands of pixels wide - too wide for web use. I therefore wrote this class to first crop the border off the image, and then resize it.

If you do actually do this though, there is an important step that needs to go in-between the cropping and the resizing. If you won't do this, you will basically get a PNG layer that is offset from the image itself - i.e. some or all of the actual image content is not visible. This happens because when the image is cropped, the origin of the image changes. It needs to be reset back to coordinates 0, 0 in order to not offset the layer itself when the image is resized.

Here's how to do it.

For Ruby/Minimagick:

image.set("page", "#{image['width']}x#{image['height']}+0+0")

For ImageMagick directly (i.e. in console):

convert [image sequence]: -set page [width]x[height]+0+0

Simple! The image should save correctly.

#mini_magick #image_magick #png #image resizing