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pipe input

Register name used to load filter: pin
This filter may be automatically loaded during graph resolution.

This filter handles generic input pipes (mono-directional) in blocking or non blocking mode.

Warning: Input pipes cannot seek.

Data format of the pipe may be specified using extension (either in file name or through ext) or MIME type through mime.
Note: Unless disabled at session level (see -no-probe ), file extensions are usually ignored and format probing is done on the first data block.

stdin pipe

The filter can handle reading from stdin, by using - or stdin as input file name.

gpac -i - vout  
gpac -i stdin vout

Named pipes

The filter can handle reading from named pipes. The associated protocol scheme is pipe:// when loaded as a generic input (e.g. -i pipe://URL where URL is a relative or absolute pipe name).
On Windows hosts, the default pipe prefix is \\.\pipe\gpac\ if no prefix is set.
dst=mypipe resolves in \\.\pipe\gpac\mypipe
dst=\\.\pipe\myapp\mypipe resolves in \\.\pipe\myapp\mypipe
Any destination name starting with \\ is used as is, with \ translated in /.

Input pipes are created by default in non-blocking mode.

The filter can create the pipe if not found using mkp. On windows hosts, this will create a pipe server.
On non windows hosts, the created pipe will delete the pipe file upon filter destruction.

Input pipes can be setup to run forever using ka. In this case:

  • any potential pipe close on the writing side will be ignored
  • pipeline flushing will be triggered upon pipe close if sigflush is set
  • final end of stream will be triggered upon session close.

This can be useful to pipe raw streams from different process into gpac:

  • Receiver side: gpac -i pipe://mypipe:ext=.264:mkp:ka
  • Sender side: cat raw1.264 > mypipe && gpac -i raw2.264 -o pipe://mypipe:ext=.264

The pipeline flush is signaled as EOS while keeping the stream active.
This is typically needed for mux filters waiting for EOS to flush their data.

If marker is set, the following strings (all 8-bytes with ``


src (cstr): name of source pipe
block_size (uint, default: 5000): buffer size used to read pipe
ext (str): indicate file extension of pipe data
mime (str): indicate mime type of pipe data
blk (bool, default: false): open pipe in block mode
ka (bool, default: false): keep-alive pipe when end of input is detected
mkp (bool, default: false): create pipe if not found
sigflush (bool, default: false): signal end of stream upon pipe close - cf filter help
marker (bool, default: false): inspect payload for flush and reconfigure signals - cf filter help
bpcnt (uint, default: 0): number of broken pipe allowed before exiting, 0 means forever
timeout (uint, default: 0): timeout in ms before considering input is in end of stream (0: no timeout)