You can check out the source code of the Browshot libraries on Github.
Python: https://github.com/juliensobrier/browshot-python
Perl: https://github.com/juliensobrier/browshot-perl
Ruby: https://github.com/juliensobrier/browshot-ruby
Don't hesitate to submit patches, bug reports, etc.
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Browshot is a web service to create real time web screenshots in a multitude of virtual devices, including mobile devices like the iPhone 3 & 4, iPad, Android Nexus, etc.
You can use the web dashboard, or our full-featured API.
Real time screenshots
15+ mobile devices: iPhone, iPad, Android, etc.
30+ desktop resolutions
Fast and reliable
Thumbnails of any size, any ratio
Full API, open-source libraries