photosort.py enables one to re-order the images in a particular directory
   for a slideshow.

    Click on the 'Directory' button to load the pictures.  Note the 'Selection'
    and press 'OK'.

    Move pictures into the required order by 'Drag and Drop'; the new place is
    in the gap under the mouse when the button is released, this includes the 
    gaps at the beginning or end of a row.

    If a picture needs to be moved a long way, or you do not yet know where it 
    should go, drag it to anywhere in the 'Image Parking' space and later 
    back to its final place.

    To delete a picture from the main gallery or the image park drag it to 
    the 'Rubbish Bin'.  The original file is not deleted.  Right clicking on a 
    picture displays a large version.

    When you are satisfied with the order you can save the files with new 
    names so that file managers will show them in the order you want.

    The new names are determined by the three characters in the box after the 
    word 'Order'.  Suppose, for example, these are '+PQ'. The file name of the 
    first picture on the screen has 'PQ' ADDED at the beginning and for 
    subsequent pictures the SECOND letter progresses through the alphabet 
    until 'Z' is reached.  The FIRST letter then moves on by one and the 
    second starts at 'A'.

    By starting the sequence of letters in different places sets of re-ordered 
    files can be merged.  The default setting is '+AA'.  Upper or lower case 
    letters are allowed but both letters must be the same case.

    It is useful to be able to re-order files a second time.  To avoid adding 
    yet more letters to the file name an option like '-PQ' can be used.  In 
    this case the first two characters of the file name are removed before the 
    new prefix is added.  Note that two characters are removed even if these had 
    NOT been added previously by the program.

    Another option is '.PQ' when the old filename is REPLACED by the pair of 
    letters, starting, in this example, with 'PQ'.

    It is also possible to use numerical file names.  In this case the option 
    should be set to THREE digits; leading zeros must be included since the 
    ordering of numerical file names is not consistent between different file 
    managers.  For example, setting the option to '012' will cause the files to 
    be named 012, 013, ... 099, 100, 101 ... .

    When you are ready click on the 'Save re-ordered' button.