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diff --git a/doc/indevs.texi b/doc/indevs.texi index b0ba6ac..a5a91fa 100644 --- a/doc/indevs.texi +++ b/doc/indevs.texi @@ -1,10 +1,10 @@ @chapter Input Devices @c man begin INPUT DEVICES -Input devices are configured elements in Libav which allow to access +Input devices are configured elements in FFmpeg which allow to access the data coming from a multimedia device attached to your system. -When you configure your Libav build, all the supported input devices +When you configure your FFmpeg build, all the supported input devices are enabled by default. You can list all available ones using the configure option "--list-indevs". @@ -42,10 +42,10 @@ specify card number or identifier, device number and subdevice number To see the list of cards currently recognized by your system check the files @file{/proc/asound/cards} and @file{/proc/asound/devices}. -For example to capture with @command{avconv} from an ALSA device with +For example to capture with @command{ffmpeg} from an ALSA device with card id 0, you may run the command: @example -avconv -f alsa -i hw:0 alsaout.wav +ffmpeg -f alsa -i hw:0 alsaout.wav @end example For more information see: @@ -55,6 +55,114 @@ For more information see: BSD video input device. +@section dshow + +Windows DirectShow input device. + +DirectShow support is enabled when FFmpeg is built with the mingw-w64 project. +Currently only audio and video devices are supported. + +Multiple devices may be opened as separate inputs, but they may also be +opened on the same input, which should improve synchronism between them. + +The input name should be in the format: + +@example +@var{TYPE}=@var{NAME}[:@var{TYPE}=@var{NAME}] +@end example + +where @var{TYPE} can be either @var{audio} or @var{video}, +and @var{NAME} is the device's name. + +@subsection Options + +If no options are specified, the device's defaults are used. +If the device does not support the requested options, it will +fail to open. + +@table @option + +@item video_size +Set the video size in the captured video. + +@item framerate +Set the framerate in the captured video. + +@item sample_rate +Set the sample rate (in Hz) of the captured audio. + +@item sample_size +Set the sample size (in bits) of the captured audio. + +@item channels +Set the number of channels in the captured audio. + +@item list_devices +If set to @option{true}, print a list of devices and exit. + +@item list_options +If set to @option{true}, print a list of selected device's options +and exit. + +@item video_device_number +Set video device number for devices with same name (starts at 0, +defaults to 0). + +@item audio_device_number +Set audio device number for devices with same name (starts at 0, +defaults to 0). + +@item pixel_format +Select pixel format to be used by DirectShow. This may only be set when +the video codec is not set or set to rawvideo. + +@item audio_buffer_size +Set audio device buffer size in milliseconds (which can directly +impact latency, depending on the device). +Defaults to using the audio device's +default buffer size (typically some multiple of 500ms). +Setting this value too low can degrade performance. +See also +@url{http://msdn.microsoft.com/en-us/library/windows/desktop/dd377582(v=vs.85).aspx} + +@end table + +@subsection Examples + +@itemize + +@item +Print the list of DirectShow supported devices and exit: +@example +$ ffmpeg -list_devices true -f dshow -i dummy +@end example + +@item +Open video device @var{Camera}: +@example +$ ffmpeg -f dshow -i video="Camera" +@end example + +@item +Open second video device with name @var{Camera}: +@example +$ ffmpeg -f dshow -video_device_number 1 -i video="Camera" +@end example + +@item +Open video device @var{Camera} and audio device @var{Microphone}: +@example +$ ffmpeg -f dshow -i video="Camera":audio="Microphone" +@end example + +@item +Print the list of supported options in selected device and exit: +@example +$ ffmpeg -list_options true -f dshow -i video="Camera" +@end example + +@end itemize + @section dv1394 Linux DV 1394 input device. @@ -72,18 +180,71 @@ For more detailed information read the file Documentation/fb/framebuffer.txt included in the Linux source tree. To record from the framebuffer device @file{/dev/fb0} with -@command{avconv}: +@command{ffmpeg}: @example -avconv -f fbdev -r 10 -i /dev/fb0 out.avi +ffmpeg -f fbdev -r 10 -i /dev/fb0 out.avi @end example You can take a single screenshot image with the command: @example -avconv -f fbdev -frames:v 1 -r 1 -i /dev/fb0 screenshot.jpeg +ffmpeg -f fbdev -frames:v 1 -r 1 -i /dev/fb0 screenshot.jpeg @end example See also @url{http://linux-fbdev.sourceforge.net/}, and fbset(1). +@section iec61883 + +FireWire DV/HDV input device using libiec61883. + +To enable this input device, you need libiec61883, libraw1394 and +libavc1394 installed on your system. Use the configure option +@code{--enable-libiec61883} to compile with the device enabled. + +The iec61883 capture device supports capturing from a video device +connected via IEEE1394 (FireWire), using libiec61883 and the new Linux +FireWire stack (juju). This is the default DV/HDV input method in Linux +Kernel 2.6.37 and later, since the old FireWire stack was removed. + +Specify the FireWire port to be used as input file, or "auto" +to choose the first port connected. + +@subsection Options + +@table @option + +@item dvtype +Override autodetection of DV/HDV. This should only be used if auto +detection does not work, or if usage of a different device type +should be prohibited. Treating a DV device as HDV (or vice versa) will +not work and result in undefined behavior. +The values @option{auto}, @option{dv} and @option{hdv} are supported. + +@item dvbuffer +Set maxiumum size of buffer for incoming data, in frames. For DV, this +is an exact value. For HDV, it is not frame exact, since HDV does +not have a fixed frame size. + +@end table + +@subsection Examples + +@itemize + +@item +Grab and show the input of a FireWire DV/HDV device. +@example +ffplay -f iec61883 -i auto +@end example + +@item +Grab and record the input of a FireWire DV/HDV device, +using a packet buffer of 100000 packets if the source is HDV. +@example +ffmpeg -f iec61883 -i auto -hdvbuffer 100000 out.mpg +@end example + +@end itemize + @section jack JACK input device. @@ -95,24 +256,24 @@ A JACK input device creates one or more JACK writable clients, one for each audio channel, with name @var{client_name}:input_@var{N}, where @var{client_name} is the name provided by the application, and @var{N} is a number which identifies the channel. -Each writable client will send the acquired data to the Libav input +Each writable client will send the acquired data to the FFmpeg input device. Once you have created one or more JACK readable clients, you need to connect them to one or more JACK writable clients. -To connect or disconnect JACK clients you can use the -@file{jack_connect} and @file{jack_disconnect} programs, or do it -through a graphical interface, for example with @file{qjackctl}. +To connect or disconnect JACK clients you can use the @command{jack_connect} +and @command{jack_disconnect} programs, or do it through a graphical interface, +for example with @command{qjackctl}. To list the JACK clients and their properties you can invoke the command -@file{jack_lsp}. +@command{jack_lsp}. Follows an example which shows how to capture a JACK readable client -with @command{avconv}. +with @command{ffmpeg}. @example -# Create a JACK writable client with name "libav". -$ avconv -f jack -i libav -y out.wav +# Create a JACK writable client with name "ffmpeg". +$ ffmpeg -f jack -i ffmpeg -y out.wav # Start the sample jack_metro readable client. $ jack_metro -b 120 -d 0.2 -f 4000 @@ -123,20 +284,175 @@ system:capture_1 system:capture_2 system:playback_1 system:playback_2 -libav:input_1 +ffmpeg:input_1 metro:120_bpm -# Connect metro to the avconv writable client. -$ jack_connect metro:120_bpm libav:input_1 +# Connect metro to the ffmpeg writable client. +$ jack_connect metro:120_bpm ffmpeg:input_1 @end example For more information read: @url{http://jackaudio.org/} +@section lavfi + +Libavfilter input virtual device. + +This input device reads data from the open output pads of a libavfilter +filtergraph. + +For each filtergraph open output, the input device will create a +corresponding stream which is mapped to the generated output. Currently +only video data is supported. The filtergraph is specified through the +option @option{graph}. + +@subsection Options + +@table @option + +@item graph +Specify the filtergraph to use as input. Each video open output must be +labelled by a unique string of the form "out@var{N}", where @var{N} is a +number starting from 0 corresponding to the mapped input stream +generated by the device. +The first unlabelled output is automatically assigned to the "out0" +label, but all the others need to be specified explicitly. + +If not specified defaults to the filename specified for the input +device. +@end table + +@subsection Examples + +@itemize +@item +Create a color video stream and play it back with @command{ffplay}: +@example +ffplay -f lavfi -graph "color=pink [out0]" dummy +@end example + +@item +As the previous example, but use filename for specifying the graph +description, and omit the "out0" label: +@example +ffplay -f lavfi color=pink +@end example + +@item +Create three different video test filtered sources and play them: +@example +ffplay -f lavfi -graph "testsrc [out0]; testsrc,hflip [out1]; testsrc,negate [out2]" test3 +@end example + +@item +Read an audio stream from a file using the amovie source and play it +back with @command{ffplay}: +@example +ffplay -f lavfi "amovie=test.wav" +@end example + +@item +Read an audio stream and a video stream and play it back with +@command{ffplay}: +@example +ffplay -f lavfi "movie=test.avi[out0];amovie=test.wav[out1]" +@end example + +@end itemize + @section libdc1394 IIDC1394 input device, based on libdc1394 and libraw1394. +@section openal + +The OpenAL input device provides audio capture on all systems with a +working OpenAL 1.1 implementation. + +To enable this input device during configuration, you need OpenAL +headers and libraries installed on your system, and need to configure +FFmpeg with @code{--enable-openal}. + +OpenAL headers and libraries should be provided as part of your OpenAL +implementation, or as an additional download (an SDK). Depending on your +installation you may need to specify additional flags via the +@code{--extra-cflags} and @code{--extra-ldflags} for allowing the build +system to locate the OpenAL headers and libraries. + +An incomplete list of OpenAL implementations follows: + +@table @strong +@item Creative +The official Windows implementation, providing hardware acceleration +with supported devices and software fallback. +See @url{http://openal.org/}. +@item OpenAL Soft +Portable, open source (LGPL) software implementation. Includes +backends for the most common sound APIs on the Windows, Linux, +Solaris, and BSD operating systems. +See @url{http://kcat.strangesoft.net/openal.html}. +@item Apple +OpenAL is part of Core Audio, the official Mac OS X Audio interface. +See @url{http://developer.apple.com/technologies/mac/audio-and-video.html} +@end table + +This device allows to capture from an audio input device handled +through OpenAL. + +You need to specify the name of the device to capture in the provided +filename. If the empty string is provided, the device will +automatically select the default device. You can get the list of the +supported devices by using the option @var{list_devices}. + +@subsection Options + +@table @option + +@item channels +Set the number of channels in the captured audio. Only the values +@option{1} (monaural) and @option{2} (stereo) are currently supported. +Defaults to @option{2}. + +@item sample_size +Set the sample size (in bits) of the captured audio. Only the values +@option{8} and @option{16} are currently supported. Defaults to +@option{16}. + +@item sample_rate +Set the sample rate (in Hz) of the captured audio. +Defaults to @option{44.1k}. + +@item list_devices +If set to @option{true}, print a list of devices and exit. +Defaults to @option{false}. + +@end table + +@subsection Examples + +Print the list of OpenAL supported devices and exit: +@example +$ ffmpeg -list_devices true -f openal -i dummy out.ogg +@end example + +Capture from the OpenAL device @file{DR-BT101 via PulseAudio}: +@example +$ ffmpeg -f openal -i 'DR-BT101 via PulseAudio' out.ogg +@end example + +Capture from the default device (note the empty string '' as filename): +@example +$ ffmpeg -f openal -i '' out.ogg +@end example + +Capture from two devices simultaneously, writing to two different files, +within the same @command{ffmpeg} command: +@example +$ ffmpeg -f openal -i 'DR-BT101 via PulseAudio' out1.ogg -f openal -i 'ALSA Default' out2.ogg +@end example +Note: not all OpenAL implementations support multiple simultaneous capture - +try the latest OpenAL Soft if the above does not work. + @section oss Open Sound System input device. @@ -145,10 +461,10 @@ The filename to provide to the input device is the device node representing the OSS input device, and is usually set to @file{/dev/dsp}. -For example to grab from @file{/dev/dsp} using @command{avconv} use the +For example to grab from @file{/dev/dsp} using @command{ffmpeg} use the command: @example -avconv -f oss -i /dev/dsp /tmp/oss.wav +ffmpeg -f oss -i /dev/dsp /tmp/oss.wav @end example For more information about OSS see: @@ -165,10 +481,10 @@ The filename to provide to the input device is a source device or the string "default" To list the pulse source devices and their properties you can invoke -the command @file{pactl list sources}. +the command @command{pactl list sources}. @example -avconv -f pulse -i default /tmp/pulse.wav +ffmpeg -f pulse -i default /tmp/pulse.wav @end example @subsection @var{server} AVOption @@ -188,7 +504,7 @@ The syntax is: @end example Specify the application name pulse will use when showing active clients, -by default it is "libav" +by default it is the LIBAVFORMAT_IDENT string @subsection @var{stream_name} AVOption @@ -248,10 +564,10 @@ The filename to provide to the input device is the device node representing the sndio input device, and is usually set to @file{/dev/audio0}. -For example to grab from @file{/dev/audio0} using @command{avconv} use the +For example to grab from @file{/dev/audio0} using @command{ffmpeg} use the command: @example -avconv -f sndio -i /dev/audio0 /tmp/oss.wav +ffmpeg -f sndio -i /dev/audio0 /tmp/oss.wav @end example @section video4linux2 @@ -268,17 +584,29 @@ Video4Linux2 devices usually support a limited set of @var{width}x@var{height} sizes and framerates. You can check which are supported using @command{-list_formats all} for Video4Linux2 devices. -Some usage examples of the video4linux2 devices with avconv and avplay: +Some usage examples of the video4linux2 devices with ffmpeg and ffplay: +The time base for the timestamps is 1 microsecond. Depending on the kernel +version and configuration, the timestamps may be derived from the real time +clock (origin at the Unix Epoch) or the monotonic clock (origin usually at +boot time, unaffected by NTP or manual changes to the clock). The +@option{-timestamps abs} or @option{-ts abs} option can be used to force +conversion into the real time clock. + +Note that if FFmpeg is build with v4l-utils support ("--enable-libv4l2" +option), it will always be used. @example # Grab and show the input of a video4linux2 device. -avplay -f video4linux2 -framerate 30 -video_size hd720 /dev/video0 +ffplay -f video4linux2 -framerate 30 -video_size hd720 /dev/video0 # Grab and record the input of a video4linux2 device, leave the framerate and size as previously set. -avconv -f video4linux2 -input_format mjpeg -i /dev/video0 out.mpeg +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 +"video4linux2". + @section vfwcap VfW (Video for Windows) capture input device. @@ -300,7 +628,7 @@ The filename passed as input has the syntax: @var{hostname}:@var{display_number}.@var{screen_number} specifies the X11 display name of the screen to grab from. @var{hostname} can be -ommitted, and defaults to "localhost". The environment variable +omitted, and defaults to "localhost". The environment variable @env{DISPLAY} contains the default display name. @var{x_offset} and @var{y_offset} specify the offsets of the grabbed @@ -309,24 +637,30 @@ default to 0. Check the X11 documentation (e.g. man X) for more detailed information. -Use the @file{dpyinfo} program for getting basic information about the +Use the @command{dpyinfo} program for getting basic information about the properties of your X11 display (e.g. grep for "name" or "dimensions"). -For example to grab from @file{:0.0} using @command{avconv}: +For example to grab from @file{:0.0} using @command{ffmpeg}: @example -avconv -f x11grab -r 25 -s cif -i :0.0 out.mpg - -# Grab at position 10,20. -avconv -f x11grab -r 25 -s cif -i :0.0+10,20 out.mpg +ffmpeg -f x11grab -r 25 -s cif -i :0.0 out.mpg @end example -@subsection @var{follow_mouse} AVOption - -The syntax is: +Grab at position @code{10,20}: @example --follow_mouse centered|@var{PIXELS} +ffmpeg -f x11grab -r 25 -s cif -i :0.0+10,20 out.mpg @end example +@subsection Options + +@table @option +@item draw_mouse +Specify whether to draw the mouse pointer. A value of @code{0} specify +not to draw the pointer. Default value is @code{1}. + +@item follow_mouse +Make the grabbed area follow the mouse. The argument can be +@code{centered} or a number of pixels @var{PIXELS}. + When it is specified with "centered", the grabbing region follows the mouse pointer and keeps the pointer at the center of region; otherwise, the region follows only when the mouse pointer reaches within @var{PIXELS} (greater than @@ -334,29 +668,37 @@ zero) to the edge of region. For example: @example -avconv -f x11grab -follow_mouse centered -r 25 -s cif -i :0.0 out.mpg - -# Follows only when the mouse pointer reaches within 100 pixels to edge -avconv -f x11grab -follow_mouse 100 -r 25 -s cif -i :0.0 out.mpg +ffmpeg -f x11grab -follow_mouse centered -r 25 -s cif -i :0.0 out.mpg @end example -@subsection @var{show_region} AVOption - -The syntax is: +To follow only when the mouse pointer reaches within 100 pixels to edge: @example --show_region 1 +ffmpeg -f x11grab -follow_mouse 100 -r 25 -s cif -i :0.0 out.mpg @end example -If @var{show_region} AVOption is specified with @var{1}, then the grabbing -region will be indicated on screen. With this option, it's easy to know what is -being grabbed if only a portion of the screen is grabbed. +@item framerate +Set the grabbing frame rate. Default value is @code{ntsc}, +corresponding to a framerate of @code{30000/1001}. + +@item show_region +Show grabbed region on screen. + +If @var{show_region} is specified with @code{1}, then the grabbing +region will be indicated on screen. With this option, it is easy to +know what is being grabbed if only a portion of the screen is grabbed. For example: @example -avconv -f x11grab -show_region 1 -r 25 -s cif -i :0.0+10,20 out.mpg +ffmpeg -f x11grab -show_region 1 -r 25 -s cif -i :0.0+10,20 out.mpg +@end example -# With follow_mouse -avconv -f x11grab -follow_mouse centered -show_region 1 -r 25 -s cif -i :0.0 out.mpg +With @var{follow_mouse}: +@example +ffmpeg -f x11grab -follow_mouse centered -show_region 1 -r 25 -s cif -i :0.0 out.mpg @end example +@item video_size +Set the video frame size. Default value is @code{vga}. +@end table + @c man end INPUT DEVICES |
