Reducing excel (xls) with pictures using a script?

Question

excel

There is a price list that is downloaded from 1C to xls with pictures, the file weight is 100 mb, if the file is saved in xlsx and run by the NX power Light program, then its size is reduced to 3 mb !!!
How can you automatically, using a script, make them an xls file weighing 100 mb, a file weighing 3 mb, without using desktop progs? The whole point is clearly in the files, because 1C saves files with a very large dpi.