Contents
Is there a way to duplicate output in FFmpeg?
The tee pseudo-muxer was added to ffmpeg on 2013-02-03, and allows you to duplicate the output to multiple files with a single instance of ffmpeg. The example below outputs an MKV file, and a UDP stream.
How does FFmpeg write to an arbitrary number of files?
From FFMpeg documentation, FFmpeg writes to an arbitrary number of output “files”. Just make sure each output file (or stream), is preceded by the proper output options.
How to use multiple FFmpeg instances in parallel?
One work around to this is to use multiple ffmpeg instances running in parallel, or possible piping from one ffmpeg to another to “do the second encoding” etc. Or if you can avoid the limiting encoder (ex: using a different faster one [ex: raw format] or just doing a raw stream copy) that might help.
What is the default value for onfail in FFmpeg?
The default value for onfail is abort . Older versions of ffmpeg can also do this, using 2 piped processes, where the first process is used to encode the stream (s) and second process is used to duplicate that to several outputs.
You don’t want to encode twice, that wastes cpu. The tee pseudo-muxer was added to ffmpeg on 2013-02-03, and allows you to duplicate the output to multiple files with a single instance of ffmpeg . The example below outputs an MKV file, and a UDP stream. Streams are separated by the | symbol.
How to reduce probing size in FFmpeg format?
The list of supported options follows: Reduce buffering. Set probing size in bytes, i.e. the size of the data to analyze to get stream information. A higher value will enable detecting more information in case it is dispersed into the stream, but will increase latency.
How are demuxers and stream specifiers defined in FFmpeg?
The exact semantics of stream specifiers is defined by the avformat_match_stream_specifier () function declared in the libavformat/avformat.h header and documented in the (ffmpeg)Stream specifiers section in the ffmpeg (1) manual . Demuxers are configured elements in FFmpeg that can read the multimedia streams from a particular type of file.