Demuxer pgm_pipe [piped pgm sequence]:
pgm demuxer AVOptions:
  -framerate         <video_rate> .D....... set the video framerate (default "25")
  -loop              <boolean>    .D....... force loop over input file sequence (default false)
  -pattern_type      <int>        .D....... set pattern type (from 0 to INT_MAX) (default 4)
     glob_sequence                .D....... select glob/sequence pattern type
     glob                         .D....... select glob pattern type
     sequence                     .D....... select sequence pattern type
     none                         .D....... disable pattern matching
  -pixel_format      <string>     .D....... set video pixel format
  -start_number      <int>        .D....... set first number in the sequence (from INT_MIN to INT_MAX) (default 0)
  -start_number_range <int>        .D....... set range for looking at the first sequence number (from 1 to INT_MAX) (default 5)
  -video_size        <image_size> .D....... set video size
  -frame_size        <int>        .D....... force frame size in bytes (from 0 to INT_MAX) (default 0)
  -ts_from_file      <int>        .D....... set frame timestamp from file's one (from 0 to 2) (default none)
     none                         .D....... none
     sec                          .D....... second precision
     ns                           .D....... nano second precision


