resizing image in photoshop: though!

[c@lle]

hello,
i want to make something that can resize an image, using e.g. photoshop.

if my image is 800 x 600, then i want to resize it so that the biggest size becomes 500 (thus 500 x 375, constrain proportions)

if my image is 600x800, it will become 375 x 500.

i've tried to use photoshop and vb, but i can't manage this. i want to convert 500 pictures, so it has to be automatic.

Are there some programs who can do that (automated batch) for a lot of pictures?

or can i do it with photoshop automation, and if yes, how?


i've tried 'sendkeys' etc. to automate photoshop, but it seems that photoshop isn't understanding the keys i send. If i send "alt+i" for the image menu, a toolbar is opened instead?! but "alt+f4" is working (closes the program).

why isn't it understanding the keys?


please help!