To upload logo to use in ABAP ALV header, go to Business Document Navigator (OAER).
Enter class name as “PICTURES”, class type as “OT” , a name for logo in object key and execute (F5).
To upload the logo, double click on screen icon.
Select the image you want to upload in the select files popup.
Enter description for the logo and press continue. Logo will be saved and you can see the success message in the status bar.