Need an expert : How to crop some pictures in a Photoshop batch?

Hi everybody,

Here is my scripting problem.

I have scanned a lot of slides and negatives with a specific scanner.

Before to scan, I haven't limited the image to strict necessary selection.

In consequence, I have thousands of photos which have 1, 2, 3 or sometime 4 borders black or white around the picture that I would like to delete.

I would like to obtain some full images without any border (even if a little part of the picture is lost during the operation).

For me, a manual cropping is too long to realize on each photo.

I would like to script this action with a photoshop batch...but how to do???

I don't want to reduce the picture without to be sure that there is some black or white on the border.

I don't want to sacrifice 10% of the picture if it is not necessary.

Pictures are not exactly on the same position on each image...it is the problem.

Is there a function which can detect these borders to crop the picture to the exact maximum size?

An example is probably better than my poor english...look at example.jpg please (I just would like to obtain the image in the red selection after the script)

Thank you in advance for your help.

I don't know how to do...

Laurent