katja.sh

#!/bin/bash
for ppt in *.ppsx
do

    mkdir tmp
    cd tmp
    unzip ../$ppt

    sed -i '' 's/slideshow/presentation/' \[Content_Types\].xml
    sed -i '' 's/x-ms-wmv/mp4/' \[Content_Types\].xml
    sed -i '' 's/wmv/mp4/' \[Content_Types\].xml
    cd ppt/media
    for f in *.wmv; do ffmpeg -i $f -c:v libx264 ${f%%.*}.mp4; rm $f; done
    cd ../slides/_rels
    for f in *.xml.rels; do sed -i '' 's/\.wmv/\.mp4/g' $f; done
    cd ../..
    sed -i '' 's/<p:modifyVerifier[ a-zA-Z0-9\"=/+]*\/>//' presentation.xml
    cd ..

    zip -r ../${ppt%%.*}-umgewandelt.pptx .
    cd ..
    rm -rf tmp

done