Paste with transparent background in Paint

If you're not afraid of typing commands and learning some very basic shell scripting, ImageMagick is a immensely powerful command-line driven open source suite to manipulate pictures available also for Windows. With it you can, among other things, do just what you asked:

• Resize can be done in plenty of manners: http://www.imagemagick.org/Usage/resize/
• For auto contrast, the "normalize" option should do: http://www.imagemagick.org/Usage/color_mods/#normalize . For all the color modification options please see the rest of the same page.
• Text overlay can be done in a plenty of ways too: http://www.imagemagick.org/Usage/annotating/
• You can crop (and border) images as documented here: http://www.imagemagick.org/Usage/crop/
• With the mogrify and convert commands (included in the ImageMagick suite) you can also rename files.

It is available on Linux and Mac too, so if you'll ever switch you will find the same tools everywhere.

Try Paint.NET for size. I tried GimpShop before, but did not like it. Paint.NET is to MS Paint what Notepad++ is to Notepad :)

To change an image to have a transparent background:

1. Install Paint.NET
2. Download AlphaMask plugin
3. Extract AlphaMask.dll to \Paint.NET\Effects (note you will likely need to unblock the file)
4. Open Paint.NET
5. Open your file
6. Copy the content you want to make have a transparent background (ctrl+a, ctrl+c to select all and copy)
7. Effects Menu > Alpha Mask...
8. check Invert Mask, check Mix Alpha, leave checked Paste from Clipboard
9. Click OK
10. File Menu > Save as, save as type PNG (*.png)
11. Defaults are fine, OK one last time

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