As you said, PDF documents can be stamped with electronic signatures or stamps using a PDF editor. But the premise is that you must cut the picture into the same number of copies as the number of pages. Moreover, the size and location of the stamp are not easy to determine.

Using the kosxpdf tool, you can automatically apply seam seals in batches without cutting the pictures. The specific process is:

1 Prepare pdf files, you can have multiple. Prepare a png stamp image with a transparent background without cutting.

2 Upload a single file or multiple files to kosxpdf, and upload the stamp image to the software.

3 Adjust the position parameters of the stamp, and the page number to be stamped with the saddle stitch stamp, and perform stamping. You can stamp the saddle stitch stamp and ordinary stamp at the same time. Support batch operations.

Advantages: No need to cut pictures, automatically assign stamps to designated pages. The seal is clear and not easy to be confused.

Disadvantages: Adjusting the stamp position requires some experience and constant experimentation to find the right position.