The Open/Save dialog includes a drop-down list of file types under the edit box. When the user picks a file type from the list, only files of the selected type are displayed in the dialog.
If AutoSetFilter is true, then ImageEn will automatically fill the dialog with all supported file types (or a specific one if you use AutoSetFilterFileType). If you wish to override the default handling, set AutoSetFilter to false and specify your preferred filter.
Note: AutoSetFilter will be set to false if you set Filter
// Only allow the user to open GIF and BMP Files OpenImageEnDialog1.AutoSetFilter := False; OpenImageEnDialog1.Filter := 'Supported Images |*.gif;*.bmp|GIF Images (*.gif)|*.gif|Bitmaps (*.bmp)|*.bmp'