What size should the background image in an MSI be?

Question

I am trying to create a Windows Installer package using Wix. I'm getting a lot of conflicting information about what size my custom background should be--the Wix documentation suggests a size of 500 x 314 pixels, but this leads to slight image distortion in the installer.

I believe that I may be indirectly using the SplashBitmap property in Windows Installer, whose documentation suggests 480 x 320 is the correct size. When I try to use this image size, I also get artefacts in the image.

Could anyone tell me what the correct size should be?

Answer 1

According to this WiX tutorial (quite a bit down towards the end of the page), they should be:

If you want to change the bitmaps or icons, just do so in the Binary directory. The front page bitmap (named Dialog.bmp here) is a 503 by 314 pixel BMP while the top banner bitmap has 500 by 63 pixels. But note that Windows Installer might stretch or shrink these bitmaps if the system font and display resolution settings of the user ask for a scaling of the whole interface.

This blog post is another pretty good resource - it shows the same dimensions for the banners.

Answer 2

After a bit more searching, I found this link on wixwiki.com, whose sizes worked correctly for me (using WiX 3). For the lazy, they are:

• Banner: 493 x 58
• Background: 493 x 312

Hope this helps someone else, too.