How to easily add cropped screenshot to self-hosted WordPress as hosted image?

I do a lot of tutorials using WordPress. The main characteristic thing is that every tutorial has a lot of screenshots. Not just whole screen shots, but fragments of screen important for explained part of tutorial. In my work i do mostly website parts screenshots.

I usually do it like this:
– press PRINT SCREEN
– open Irfan View
– paste whole screen capture
– crop part i need
– save it do disc of my computer
– click “add image” in wordpress
– choose the image from disc
– voila, one image is added to post

And when i write 1 tutorial post i do it like 20-30 times…
So my problem is that it takes like “A LOT” of time.

And search some plugins to help me with this work. I use Firefox, but have also Chrome and Opera. I’ve found “Light Shot” plugin for Firefox. It’ basically gives you option to select part of webpage and save it to it’s website or clipboard. But unfortunately you can not embedd the image from their server in wordpress.

So i pasted clipboard images to blog post. But when i do this images are embedded as inline images. It worked for short tutorials. But when i saved tutorial with 5 images WordPress cut it in half and saved only half of my post.

And even if i would fix it somehow i dont want to have inline images, because it would kill my server performance and you can’t share the image in other posts.

So i thought i ask you guys if you know any solution to make screengrabbing to WordPress easier. Maybe there is ready solution I didn’t know before.

UPDATE:
Light Shot can take cropped screenshot to clipboard. So what i would need now is a extension or application that can upload image from clipboard to WordPress gallery. Do you know any?