Computers to Reassemble Shredded East German Secret Police Files

BERLIN – German researchers said Wednesday that they were launching an attempt to reassemble millions of shredded East German secret police files using complicated computerized algorithms.

The files were shredded as the Berlin Wall fell in 1989 and it became clear that the East German regime was finished.

Panicking officials of the Stasi secret police attempted to destroy the vast volumes of material they had kept on everyone from their own citizens to foreign leaders.

So great was the task that it overwhelmed the shredding machines, and a large number of the documents were torn by hand into between eight and thirty pieces.

Some 16,250 sacks containing pieces of 45 million shredded documents were found and confiscated after the reunification of Germany in 1990. Reconstruction work began 12 years ago but 24 people have been able to reassemble the contents of only 323 sacks.

"Many important documents are slumbering in these sacks," Marianne Birthler, head of the Stasi archives, told Deutschlandfunk radio.

Berlin's Fraunhofer Institute for Production Systems and Design Technology estimates that putting everything back together by hand would take 30 people 600 to 800 years.

Researchers are hopeful they will be able to put together 400 sacks in two years using new computer technology employed by the Frauenhofer Institute.

If the government-funded $8.53 million pilot project is successful, head researcher Bertram Nickolay said, researchers will be able to put together all of the bags in four to five years.

Using algorithms developed 15 years ago to help decipher barely legible lists of Nazi concentration camp victims, each individual strip of the shredded Stasi files will be scanned on both sides.

The data then will be fed into the computer for interpretation using color recognition; texture analysis; shape and pattern recognition; machine and handwriting analysis and the recognition of forged official stamps, Nickolay said in a statement.

Hand-torn documents are expected to be the easiest to reassemble, because the pieces can be matched together by shape, like a complicated puzzle.

Putting the machine-shredded documents together requires analysis of the script on the surface of the fragments.

The institute has already had success putting together similarly destroyed documents for Germany's tax authorities.