Reserved command-line keywords

The following keywords can be specified before the command line. They are interpreted by the filter and removed from the final command line passed to FFmpeg. E.g.:

SHOWCONSOLE NOLOG ffmpegLGPL.exe -i %PIPE% myclip.webm

PAUSEWHENSTOP

If specified, when the graph is stopped, the FFmpeg recording is paused (instead of being stopped as well). When the graph is run again, the FFmpeg recording is resumed. So this lets record a single, continuous clip without gap, although the graph has been stopped and restarted, whatever the interval of time between the stops and starts.

When this keyword is used, the recording is finally closed by invoking Stop_PauseWhenStop. If it is never invoked, the clip is closed when the application exits.

Note: while the graph is stopped, the video and audio pins must not be disconnected / reconnected.

See also PauseEncoder / ResumeEncoder, which pause the encoding without stopping the graph.

SHOWCONSOLE

Makes the console visible. Mainly for debugging purpose. In this mode the FFmpeg information (e.g. current time, frame count) is not available through the filter interface.

NOLOG

Can be specified to save CPU. If specified, the filter does not analyze the FFmpeg progress information (e.g. current time, frame count), so the filter does not report them.

Note: this keyword is ignored in the evaluation version.

LOWLATENCY

Specify it if the filter is used for a live streaming in real time (e.g. to send the stream to a Wowza server).

NOABORTONERROR

If there is an error (e.g. if the syntax is not correct and/or if FFmpeg exits by itself with an error code), the filter sends an EC_ERRORABORT notification to the graph, that stops the graph.

If NOABORTONERROR is specified, the filter sends instead a "neutral" EC_MPE_TERMINATED_ERROR notification to the graph that can be handled, but the graph does not stop. See Graph event notifications.

DONTOVERWRITE

By default, if the command line contains "FFmpeg", the filter passes the -y option to FFmpeg to overwrite a previous clip, if any.

Set this option to prevent overwriting an existing file, however it is NOT RECOMMENDED to use it, because if SHOWCONSOLE is disabled and FFmpeg waits for the overwrite confirmation, the graph will just hang.

TOPDOWN

If specified, the image is flipped vertically without extra CPU load. Can be required by some encoders if the image appears inverted.

COMPRESS

If specified, the video stream is passed through the pipe compressed in MPEG-4. If the command-line transcoder does not accept the pipe uncompressed, enabling this option could fix the problem.

Note that enabling this option will significantly increase the CPU load.

NOTREALTIME

Tells the filter that the source must not be treated as a real-time source, even when it is a live one. See also Real-time mode.

LIVETIMING

Enables the live timing of the internal bridge, for the graphs whose source delivers its samples in real time.