ok, now i know the filename.
so you make your bash file
nano /home/pi/.config/autostart/start_processing
with this content:
#!/bin/bash
# /home/pi/.config/autostart/start_processing
# this will not do anything unless called by a .desktop file
echo '10s'
env sleep 5
echo '5s'
env sleep 5
#...
cd /home/pi/Desktop/application.linux-armv6hf/
bash combine_horizontal_and_vertical
# wait for operator to close window
read -p "press enter to close terminal window"
make it executable
chmod +x /home/pi/.config/autostart/start_processing
and test it
if the test works you can test the desktop file
/home/pi/.config/autostart/myautostart.desktop
also with double click