if you've created a Windows Phone 7 with the Socialviewer template at http://socialviewer.codeplex.com you might have spotted that it takes longer to create the icons and marketplace images than it does to create the application so I wanted a quick way to batch process the main images. I had been doing with paint.net and it was a bit tedious. So here's a quick way and a small batch file.
First up create your base image.png and square it up, ideally 200 x 200px minimum, give it a decent name Paint.net good for this and free.
create a wee batch file
REM Create Windows Phone 7 Icons and Marketplace Images in a flash
for /f "tokens=1,2 delims=. " %%a in ("%1") do set name=%%a&set ext=%%b
convert %1 -resize 99x99 %name%99x99.png
convert %1 -resize 173x173 %name%173x173.png
convert %1 -resize 200x200 %name%200x200.png
convert %1 -resize 62x62 ApplicationIcon.png
convert %1 -resize 173x173 StartScreenIcon.png
Drag and drop your base image on to the bat file in Windows Explorer and the job is done:)
I've attached the bat file to this posting.
Paint.net and ImageMagicK well respected bits of software, your milage may vary, no liability accepted etc...