See also: How to Increase / Decrease Size of Images in Word Document using VBA

How to Programatically Compress Pictures/Images in Excel using VBA

If you are trying to compress pictures, you will normally be doing using the following dialog:

Compress Pictures Excel Dialog

Compress Pictures Excel Dialog



The same dialog can be automated using Excel VBA and SendKeys as shown below:

Sub Compress_PIX()

Dim octl As CommandBarControl

With Selection
    Set octl = Application.CommandBars.FindControl(ID:=6382)
    Application.SendKeys "%e~"
    Application.SendKeys "%a~"
     octl.Execute
End With

End Sub 

Supressing "Compressing Pictures May reduce the quality of your images.." dialog is also taken care by SendKeys

The code uses CommandBarControl to find the Command and then execute the dialog

See also: How to Increase / Decrease Size of Images in Word Document using VBA