1 @chapter Output Devices
2 @c man begin OUTPUT DEVICES
4 Output devices are configured elements in FFmpeg which allow to write
5 multimedia data to an output device attached to your system.
7 When you configure your FFmpeg build, all the supported output devices
8 are enabled by default. You can list all available ones using the
9 configure option "--list-outdevs".
11 You can disable all the output devices using the configure option
12 "--disable-outdevs", and selectively enable an output device using the
13 option "--enable-outdev=@var{OUTDEV}", or you can disable a particular
14 input device using the option "--disable-outdev=@var{OUTDEV}".
16 The option "-formats" of the ff* tools will display the list of
17 enabled output devices (amongst the muxers).
19 A description of the currently available output devices follows.
23 ALSA (Advanced Linux Sound Architecture) output device.
29 This output device allows to show a video stream in CACA window.
30 Only one CACA window is allowed per application, so you can
31 have only one instance of this output device in an application.
33 To enable this output device you need to configure FFmpeg with
34 @code{--enable-libcaca}.
35 libcaca is a graphics library that outputs text instead of pixels.
37 For more information about libcaca, check:
38 @url{http://caca.zoy.org/wiki/libcaca}
45 Set the CACA window title, if not specified default to the filename
46 specified for the output device.
49 Set the CACA window size, can be a string of the form
50 @var{width}x@var{height} or a video size abbreviation.
51 If not specified it defaults to the size of the input video.
57 Set dithering algorithm. Dithering is necessary
58 because the picture being rendered has usually far more colours than
59 the available palette.
60 The accepted values are listed with @code{-list_dither algorithms}.
63 Set antialias method. Antialiasing smoothens the rendered
64 image and avoids the commonly seen staircase effect.
65 The accepted values are listed with @code{-list_dither antialiases}.
68 Set which characters are going to be used when rendering text.
69 The accepted values are listed with @code{-list_dither charsets}.
72 Set color to be used when rendering text.
73 The accepted values are listed with @code{-list_dither colors}.
76 If set to @option{true}, print a list of available drivers and exit.
79 List available dither options related to the argument.
80 The argument must be one of @code{algorithms}, @code{antialiases},
81 @code{charsets}, @code{colors}.
88 The following command shows the @command{ffmpeg} output is an
89 CACA window, forcing its size to 80x25:
91 ffmpeg -i INPUT -vcodec rawvideo -pix_fmt rgb24 -window_size 80x25 -f caca -
95 Show the list of available drivers and exit:
97 ffmpeg -i INPUT -pix_fmt rgb24 -f caca -list_drivers true -
101 Show the list of available dither colors and exit:
103 ffmpeg -i INPUT -pix_fmt rgb24 -f caca -list_dither colors -
109 OSS (Open Sound System) output device.
113 SDL (Simple DirectMedia Layer) output device.
115 This output device allows to show a video stream in an SDL
116 window. Only one SDL window is allowed per application, so you can
117 have only one instance of this output device in an application.
119 To enable this output device you need libsdl installed on your system
120 when configuring your build.
122 For more information about SDL, check:
123 @url{http://www.libsdl.org/}
130 Set the SDL window title, if not specified default to the filename
131 specified for the output device.
134 Set the name of the iconified SDL window, if not specified it is set
135 to the same value of @var{window_title}.
138 Set the SDL window size, can be a string of the form
139 @var{width}x@var{height} or a video size abbreviation.
140 If not specified it defaults to the size of the input video,
141 downscaled according to the aspect ratio.
146 The following command shows the @command{ffmpeg} output is an
147 SDL window, forcing its size to the qcif format:
149 ffmpeg -i INPUT -vcodec rawvideo -pix_fmt yuv420p -window_size qcif -f sdl "SDL output"
154 sndio audio output device.
158 XV (XVideo) output device.
160 This output device allows to show a video stream in a X Window System
167 Specify the hardware display name, which determines the display and
168 communications domain to be used.
170 The display name or DISPLAY environment variable can be a string in
171 the format @var{hostname}[:@var{number}[.@var{screen_number}]].
173 @var{hostname} specifies the name of the host machine on which the
174 display is physically attached. @var{number} specifies the number of
175 the display server on that host machine. @var{screen_number} specifies
176 the screen to be used on that server.
178 If unspecified, it defaults to the value of the DISPLAY environment
181 For example, @code{dual-headed:0.1} would specify screen 1 of display
182 0 on the machine named ``dual-headed''.
184 Check the X11 specification for more detailed information about the
188 Set the created window size, can be a string of the form
189 @var{width}x@var{height} or a video size abbreviation. If not
190 specified it defaults to the size of the input video.
194 Set the X and Y window offsets for the created window. They are both
195 set to 0 by default. The values may be ignored by the window manager.
198 Set the window title, if not specified default to the filename
199 specified for the output device.
202 For more information about XVideo see @url{http://www.x.org/}.
208 Decode, display and encode video input with @command{ffmpeg} at the
211 ffmpeg -i INPUT OUTPUT -f xv display
215 Decode and display the input video to multiple X11 windows:
217 ffmpeg -i INPUT -f xv normal -vf negate -f xv negated
221 @c man end OUTPUT DEVICES