How to debug
First verify if the solution is not in the FAQ and troubleshooting section. If not:
- add
SHOWCONSOLEat the beginning of the command line, to see if the FFmpeg process starts and if any red error report appears, - add
-reportor-report -loglevel debugto the command line, this will generate the FFmpeg log file in the current folder.
Verify/fix the FFmpeg syntax, then try again.
PS: don't forget to remove the report and loglevel statements afterwards because they slow down the filter.