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Diffstat (limited to 'doc')
| -rw-r--r-- | doc/indevs.texi | 35 |
1 files changed, 10 insertions, 25 deletions
diff --git a/doc/indevs.texi b/doc/indevs.texi index 3b2c86290c..782c67fc35 100644 --- a/doc/indevs.texi +++ b/doc/indevs.texi @@ -504,9 +504,9 @@ command: ffmpeg -f sndio -i /dev/audio0 /tmp/oss.wav @end example -@section video4linux and video4linux2 +@section video4linux2 -Video4Linux and Video4Linux2 input video devices. +Video4Linux2 input video device. The name of the device to grab is a file device node, usually Linux systems tend to automatically create such nodes when the device @@ -514,36 +514,21 @@ systems tend to automatically create such nodes when the device kind @file{/dev/video@var{N}}, where @var{N} is a number associated to the device. -Video4Linux and Video4Linux2 devices only support a limited set of +Video4Linux2 devices usually support a limited set of @var{width}x@var{height} sizes and framerates. You can check which are -supported for example with the command @command{dov4l} for Video4Linux -devices and using @command{-list_formats all} for Video4Linux2 devices. +supported using @command{-list_formats all} for Video4Linux2 devices. -If the size for the device is set to 0x0, the input device will -try to auto-detect the size to use. -Only for the video4linux2 device, if the frame rate is set to 0/0 the -input device will use the frame rate value already set in the driver. - -Video4Linux support is deprecated since Linux 2.6.30, and will be -dropped in later versions. +Some usage examples of the video4linux2 devices with ffmpeg and ffplay: Note that if FFmpeg is build with v4l-utils support ("--enable-libv4l2" option), it will always be used. - -Follow some usage examples of the video4linux devices with the ff* -tools. @example -# Grab and show the input of a video4linux device, frame rate is set -# to the default of 25/1. -ffplay -s 320x240 -f video4linux /dev/video0 - -# Grab and show the input of a video4linux2 device, auto-adjust size. -ffplay -f video4linux2 /dev/video0 +# Grab and show the input of a video4linux2 device. +ffplay -f video4linux2 -framerate 30 -video_size hd720 /dev/video0 -# Grab and record the input of a video4linux2 device, auto-adjust size, -# frame rate value defaults to 0/0 so it is read from the video4linux2 -# driver. -ffmpeg -f video4linux2 -i /dev/video0 out.mpeg +# Grab and record the input of a video4linux2 device, leave the +framerate and size as previously set. +ffmpeg -f video4linux2 -input_format mjpeg -i /dev/video0 out.mpeg @end example "v4l" and "v4l2" can be used as aliases for the respective "video4linux" and |