asettb

Set the timebase to use for the output frames timestamps. It is mainly useful for testing timebase configuration.

It accepts the following parameters:

expr, tb

The expression which is evaluated into the output timebase.

The value for tb is an arithmetic expression representing a rational. The expression can contain the constants "AVTB" (the default timebase), "intb" (the input timebase) and "sr" (the sample rate, audio only). Default value is "intb".

Examples

  • Set the timebase to 1/25:
    settb=expr=1/25
    
  • Set the timebase to 1/10:
    settb=expr=0.1
    
  • Set the timebase to 1001/1000:
    settb=1+0.001
    
  • Set the timebase to 2*intb:
    settb=2*intb
    
  • Set the default timebase value:
    settb=AVTB