How to reduce the size of an image in C# and .NET 3.5?

Question

I have a screen shot I take in my mobile app. The screen shot takes about 32 KB when saved as a png on a disk.

I am sending these to a central SQL Server and 32 KB

Answer 1

Change the color palette to a lower color depth. Take a look at this question (well look at the answert really) which shows converting to 1bpp. You could go to 8bpp instead of 1bpp and have significant size savings. The mechanism for conversion will be the same as what is shown.

EDIT

Thinking out of the box, you might also consider just sending the data points from the upper part of the screen and the signature vector, and have the server recreate the screen for you. If size really is a big issue, I'd probably investigate that.

EDIT 2

If simply resizing the image is a reasonable solution (you'll obviously lose data in doing so) then you can use the Imaging namespace in the SDF to create a thumbnail as Alex explains here.