User:Joger/FFmpeg: Difference between revisions

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Useful options  
Useful options  


*<tt>-v error</tt> suppresses FFprobe's header and decoding information, so we only see the interesting output information.
*<tt>'''-v error'''</tt> suppresses FFprobe's header and decoding information, so we only see the interesting output information.
*<tt>-print_format json</tt> argument makes the output easier to read.
*<tt>-print_format json</tt> argument makes the output easier to read.
*<tt>-select_streams v</tt> argument will only print '''v'''ideo streams.  It can be replaced by <tt>'''a'''</tt> to show only '''a'''udio streams, or '''s''' to show only '''s'''ubtitle streams.
*<tt>-select_streams v</tt> argument will only print '''v'''ideo streams.  It can be replaced by <tt>'''a'''</tt> to show only '''a'''udio streams, or '''s''' to show only '''s'''ubtitle streams.

Revision as of 10:46, 25 August 2024

FFProbe

FFProbe is used to inspect media, for example to view format or stream information. You can use the following command line to view a file's format and stream information. It will print out information about the file's streams, such as video and audio streams, as well as the container format.

ffprobe -v error -show_streams -show_format -print_format json <name_of_media>

Useful options

  • -v error suppresses FFprobe's header and decoding information, so we only see the interesting output information.
  • -print_format json argument makes the output easier to read.
  • -select_streams v argument will only print video streams. It can be replaced by a to show only audio streams, or s to show only subtitle streams.

FFMpeg

Low latency streaming

> mediamtx
> ffmpeg -filter_complex ddagrab=video_size=1024x890:output_idx=0:framerate=60,hwdownload,format=bgra -fflags nobuffer -vcodec libx264 -tune zerolatency -f rtsp rtsp://127.0.0.1:8554/webcam.h264
> ffplay rtsp://127.0.0.1:8554/webcam.h264 -fflags nobuffer -flags low_delay -framedrop