A filtergraph can be represented using a textual representation, which is
recognized by the @option{-filter}/@option{-vf} and @option{-filter_complex}
-options in @command{avconv} and @option{-vf} in @command{avplay}, and by the
+options in @command{ffmpeg} and @option{-vf} in @command{ffplay}, and by the
@code{avfilter_graph_parse()}/@code{avfilter_graph_parse2()} function defined in
@file{libavfilter/avfiltergraph.h}.
@chapter Audio Filters
@c man begin AUDIO FILTERS
-When you configure your Libav build, you can disable any of the
-existing filters using --disable-filters.
+When you configure your FFmpeg build, you can disable any of the
+existing filters using @code{--disable-filters}.
The configure output will show the audio filters included in your
build.
Below is a description of the currently available audio filters.
+@section aconvert
+
+Convert the input audio format to the specified formats.
+
+The filter accepts a string of the form:
+"@var{sample_format}:@var{channel_layout}".
+
+@var{sample_format} specifies the sample format, and can be a string or the
+corresponding numeric value defined in @file{libavutil/samplefmt.h}. Use 'p'
+suffix for a planar sample format.
+
+@var{channel_layout} specifies the channel layout, and can be a string
+or the corresponding number value defined in @file{libavutil/audioconvert.h}.
+
+The special parameter "auto", signifies that the filter will
+automatically select the output format depending on the output filter.
+
+Some examples follow.
+
+@itemize
+@item
+Convert input to float, planar, stereo:
+@example
+aconvert=fltp:stereo
+@end example
+
+@item
+Convert input to unsigned 8-bit, automatically select out channel layout:
+@example
+aconvert=u8:auto
+@end example
+@end itemize
+
+@section aformat
+
+Convert the input audio to one of the specified formats. The framework will
+negotiate the most appropriate format to minimize conversions.
+
+The filter accepts three lists of formats, separated by ":", in the form:
+"@var{sample_formats}:@var{channel_layouts}".
+
+Elements in each list are separated by "," which has to be escaped in the
+filtergraph specification.
+
+The special parameter "all", in place of a list of elements, signifies all
+supported formats.
+
+Some examples follow:
+@example
+aformat=u8\\,s16:mono
+
+aformat=s16:mono\\,stereo
+@end example
+
+@section amerge
+
+Merge two audio streams into a single multi-channel stream.
+
+This filter does not need any argument.
+
+If the channel layouts of the inputs are disjoint, and therefore compatible,
+the channel layout of the output will be set accordingly and the channels
+will be reordered as necessary. If the channel layouts of the inputs are not
+disjoint, the output will have all the channels of the first input then all
+the channels of the second input, in that order, and the channel layout of
+the output will be the default value corresponding to the total number of
+channels.
+
+For example, if the first input is in 2.1 (FL+FR+LF) and the second input
+is FC+BL+BR, then the output will be in 5.1, with the channels in the
+following order: a1, a2, b1, a3, b2, b3 (a1 is the first channel of the
+first input, b1 is the first channel of the second input).
+
+On the other hand, if both input are in stereo, the output channels will be
+in the default order: a1, a2, b1, b2, and the channel layout will be
+arbitrarily set to 4.0, which may or may not be the expected value.
+
+Both inputs must have the same sample rate, and format.
+
+If inputs do not have the same duration, the output will stop with the
+shortest.
+
+Example: merge two mono files into a stereo stream:
+@example
+amovie=left.wav [l] ; amovie=right.mp3 [r] ; [l] [r] amerge
+@end example
+
+If you need to do multiple merges (for instance multiple mono audio streams in
+a single video media), you can do:
+@example
+ffmpeg -f lavfi -i "
+amovie=input.mkv:si=0 [a0];
+amovie=input.mkv:si=1 [a1];
+amovie=input.mkv:si=2 [a2];
+amovie=input.mkv:si=3 [a3];
+amovie=input.mkv:si=4 [a4];
+amovie=input.mkv:si=5 [a5];
+[a0][a1] amerge [x0];
+[x0][a2] amerge [x1];
+[x1][a3] amerge [x2];
+[x2][a4] amerge [x3];
+[x3][a5] amerge" -c:a pcm_s16le output.mkv
+@end example
+
@section aformat
Convert the input audio to one of the specified formats. The framework will
Pass the audio source unchanged to the output.
+@section aresample
+
+Resample the input audio to the specified sample rate.
+
+The filter accepts exactly one parameter, the output sample rate. If not
+specified then the filter will automatically convert between its input
+and output sample rates.
+
+For example, to resample the input audio to 44100Hz:
+@example
+aresample=44100
+@end example
+
+@section ashowinfo
+
+Show a line containing various information for each input audio frame.
+The input audio is not modified.
+
+The shown line contains a sequence of key/value pairs of the form
+@var{key}:@var{value}.
+
+A description of each shown parameter follows:
+
+@table @option
+@item n
+sequential number of the input frame, starting from 0
+
+@item pts
+presentation TimeStamp of the input frame, expressed as a number of
+time base units. The time base unit depends on the filter input pad, and
+is usually 1/@var{sample_rate}.
+
+@item pts_time
+presentation TimeStamp of the input frame, expressed as a number of
+seconds
+
+@item pos
+position of the frame in the input stream, -1 if this information in
+unavailable and/or meaningless (for example in case of synthetic audio)
+
+@item fmt
+sample format name
+
+@item chlayout
+channel layout description
+
+@item nb_samples
+number of samples (per each channel) contained in the filtered frame
+
+@item rate
+sample rate for the audio frame
+
+@item checksum
+Adler-32 checksum (printed in hexadecimal) of all the planes of the input frame
+
+@item plane_checksum
+Adler-32 checksum (printed in hexadecimal) for each input frame plane,
+expressed in the form "[@var{c0} @var{c1} @var{c2} @var{c3} @var{c4} @var{c5}
+@var{c6} @var{c7}]"
+@end table
+
@section asplit
Split input audio into several identical outputs.
The filter accepts a single parameter which specifies the number of outputs. If
unspecified, it defaults to 2.
-For example
+For example:
@example
-avconv -i INPUT -filter_complex asplit=5 OUTPUT
+[in] asplit [out0][out1]
+@end example
+
+will create two separate outputs from the same input.
+
+To create 3 or more outputs, you need to specify the number of
+outputs, like in:
+@example
+[in] asplit=3 [out0][out1][out2]
+@end example
+
+@example
+ffmpeg -i INPUT -filter_complex asplit=5 OUTPUT
@end example
will create 5 copies of the input audio.
+
+@section astreamsync
+
+Forward two audio streams and control the order the buffers are forwarded.
+
+The argument to the filter is an expression deciding which stream should be
+forwarded next: if the result is negative, the first stream is forwarded; if
+the result is positive or zero, the second stream is forwarded. It can use
+the following variables:
+
+@table @var
+@item b1 b2
+number of buffers forwarded so far on each stream
+@item s1 s2
+number of samples forwarded so far on each stream
+@item t1 t2
+current timestamp of each stream
+@end table
+
+The default value is @code{t1-t2}, which means to always forward the stream
+that has a smaller timestamp.
+
+Example: stress-test @code{amerge} by randomly sending buffers on the wrong
+input, while avoiding too much of a desynchronization:
+@example
+amovie=file.ogg [a] ; amovie=file.mp3 [b] ;
+[a] [b] astreamsync=(2*random(1))-1+tanh(5*(t1-t2)) [a2] [b2] ;
+[a2] [b2] amerge
+@end example
+
+@section earwax
+
+Make audio easier to listen to on headphones.
+
+This filter adds `cues' to 44.1kHz stereo (i.e. audio CD format) audio
+so that when listened to on headphones the stereo image is moved from
+inside your head (standard for headphones) to outside and in front of
+the listener (standard for speakers).
+
+Ported from SoX.
+
+@section pan
+
+Mix channels with specific gain levels. The filter accepts the output
+channel layout followed by a set of channels definitions.
+
+This filter is also designed to remap efficiently the channels of an audio
+stream.
+
+The filter accepts parameters of the form:
+"@var{l}:@var{outdef}:@var{outdef}:..."
+
+@table @option
+@item l
+output channel layout or number of channels
+
+@item outdef
+output channel specification, of the form:
+"@var{out_name}=[@var{gain}*]@var{in_name}[+[@var{gain}*]@var{in_name}...]"
+
+@item out_name
+output channel to define, either a channel name (FL, FR, etc.) or a channel
+number (c0, c1, etc.)
+
+@item gain
+multiplicative coefficient for the channel, 1 leaving the volume unchanged
+
+@item in_name
+input channel to use, see out_name for details; it is not possible to mix
+named and numbered input channels
+@end table
+
+If the `=' in a channel specification is replaced by `<', then the gains for
+that specification will be renormalized so that the total is 1, thus
+avoiding clipping noise.
+
+@subsection Mixing examples
+
+For example, if you want to down-mix from stereo to mono, but with a bigger
+factor for the left channel:
+@example
+pan=1:c0=0.9*c0+0.1*c1
+@end example
+
+A customized down-mix to stereo that works automatically for 3-, 4-, 5- and
+7-channels surround:
+@example
+pan=stereo: FL < FL + 0.5*FC + 0.6*BL + 0.6*SL : FR < FR + 0.5*FC + 0.6*BR + 0.6*SR
+@end example
+
+Note that @command{ffmpeg} integrates a default down-mix (and up-mix) system
+that should be preferred (see "-ac" option) unless you have very specific
+needs.
+
+@subsection Remapping examples
+
+The channel remapping will be effective if, and only if:
+
+@itemize
+@item gain coefficients are zeroes or ones,
+@item only one input per channel output,
+@end itemize
+
+If all these conditions are satisfied, the filter will notify the user ("Pure
+channel mapping detected"), and use an optimized and lossless method to do the
+remapping.
+
+For example, if you have a 5.1 source and want a stereo audio stream by
+dropping the extra channels:
+@example
+pan="stereo: c0=FL : c1=FR"
+@end example
+
+Given the same source, you can also switch front left and front right channels
+and keep the input channel layout:
+@example
+pan="5.1: c0=c1 : c1=c0 : c2=c2 : c3=c3 : c4=c4 : c5=c5"
+@end example
+
+If the input is a stereo audio stream, you can mute the front left channel (and
+still keep the stereo channel layout) with:
+@example
+pan="stereo:c1=c1"
+@end example
+
+Still with a stereo audio stream input, you can copy the right channel in both
+front left and right:
+@example
+pan="stereo: c0=FR : c1=FR"
+@end example
+
+@section silencedetect
+
+Detect silence in an audio stream.
+
+This filter logs a message when it detects that the input audio volume is less
+or equal to a noise tolerance value for a duration greater or equal to the
+minimum detected noise duration.
+
+The printed times and duration are expressed in seconds.
+
+@table @option
+@item duration, d
+Set silence duration until notification (default is 2 seconds).
+
+@item noise, n
+Set noise tolerance. Can be specified in dB (in case "dB" is appended to the
+specified value) or amplitude ratio. Default is -60dB, or 0.001.
+@end table
+
+Detect 5 seconds of silence with -50dB noise tolerance:
+@example
+silencedetect=n=-50dB:d=5
+@end example
+
+Complete example with @command{ffmpeg} to detect silence with 0.0001 noise
+tolerance in @file{silence.mp3}:
+@example
+ffmpeg -f lavfi -i amovie=silence.mp3,silencedetect=noise=0.0001 -f null -
+@end example
+
+@section volume
+
+Adjust the input audio volume.
+
+The filter accepts exactly one parameter @var{vol}, which expresses
+how the audio volume will be increased or decreased.
+
+Output values are clipped to the maximum value.
+
+If @var{vol} is expressed as a decimal number, the output audio
+volume is given by the relation:
+@example
+@var{output_volume} = @var{vol} * @var{input_volume}
+@end example
+
+If @var{vol} is expressed as a decimal number followed by the string
+"dB", the value represents the requested change in decibels of the
+input audio power, and the output audio volume is given by the
+relation:
+@example
+@var{output_volume} = 10^(@var{vol}/20) * @var{input_volume}
+@end example
+
+Otherwise @var{vol} is considered an expression and its evaluated
+value is used for computing the output audio volume according to the
+first relation.
+
+Default value for @var{vol} is 1.0.
+
+@subsection Examples
+
+@itemize
+@item
+Half the input audio volume:
+@example
+volume=0.5
+@end example
+
+The above example is equivalent to:
+@example
+volume=1/2
+@end example
+
+@item
+Decrease input audio power by 12 decibels:
+@example
+volume=-12dB
+@end example
+@end itemize
+
@section asyncts
Synchronize audio data with timestamps by squeezing/stretching it and/or
dropping samples/adding silence when needed.
@section resample
Convert the audio sample format, sample rate and channel layout. This filter is
-not meant to be used directly, it is inserted automatically by libavfilter
-whenever conversion is needed. Use the @var{aformat} filter to force a specific
-conversion.
+not meant to be used directly.
@c man end AUDIO FILTERS
Below is a description of the currently available audio sources.
+@section abuffer
+
+Buffer audio frames, and make them available to the filter chain.
+
+This source is mainly intended for a programmatic use, in particular
+through the interface defined in @file{libavfilter/asrc_abuffer.h}.
+
+It accepts the following mandatory parameters:
+@var{sample_rate}:@var{sample_fmt}:@var{channel_layout}
+
+@table @option
+
+@item sample_rate
+The sample rate of the incoming audio buffers.
+
+@item sample_fmt
+The sample format of the incoming audio buffers.
+Either a sample format name or its corresponging integer representation from
+the enum AVSampleFormat in @file{libavutil/samplefmt.h}
+
+@item channel_layout
+The channel layout of the incoming audio buffers.
+Either a channel layout name from channel_layout_map in
+@file{libavutil/audioconvert.c} or its corresponding integer representation
+from the AV_CH_LAYOUT_* macros in @file{libavutil/audioconvert.h}
+
+@end table
+
+For example:
+@example
+abuffer=44100:s16p:stereo
+@end example
+
+will instruct the source to accept planar 16bit signed stereo at 44100Hz.
+Since the sample format with name "s16p" corresponds to the number
+6 and the "stereo" channel layout corresponds to the value 0x3, this is
+equivalent to:
+@example
+abuffer=44100:6:0x3
+@end example
+
+@section aevalsrc
+
+Generate an audio signal specified by an expression.
+
+This source accepts in input one or more expressions (one for each
+channel), which are evaluated and used to generate a corresponding
+audio signal.
+
+It accepts the syntax: @var{exprs}[::@var{options}].
+@var{exprs} is a list of expressions separated by ":", one for each
+separate channel. In case the @var{channel_layout} is not
+specified, the selected channel layout depends on the number of
+provided expressions.
+
+@var{options} is an optional sequence of @var{key}=@var{value} pairs,
+separated by ":".
+
+The description of the accepted options follows.
+
+@table @option
+
+@item channel_layout, c
+Set the channel layout. The number of channels in the specified layout
+must be equal to the number of specified expressions.
+
+@item duration, d
+Set the minimum duration of the sourced audio. See the function
+@code{av_parse_time()} for the accepted format.
+Note that the resulting duration may be greater than the specified
+duration, as the generated audio is always cut at the end of a
+complete frame.
+
+If not specified, or the expressed duration is negative, the audio is
+supposed to be generated forever.
+
+@item nb_samples, n
+Set the number of samples per channel per each output frame,
+default to 1024.
+
+@item sample_rate, s
+Specify the sample rate, default to 44100.
+@end table
+
+Each expression in @var{exprs} can contain the following constants:
+
+@table @option
+@item n
+number of the evaluated sample, starting from 0
+
+@item t
+time of the evaluated sample expressed in seconds, starting from 0
+
+@item s
+sample rate
+
+@end table
+
+@subsection Examples
+
+@itemize
+
+@item
+Generate silence:
+@example
+aevalsrc=0
+@end example
+
+@item
+
+Generate a sin signal with frequency of 440 Hz, set sample rate to
+8000 Hz:
+@example
+aevalsrc="sin(440*2*PI*t)::s=8000"
+@end example
+
+@item
+Generate a two channels signal, specify the channel layout (Front
+Center + Back Center) explicitly:
+@example
+aevalsrc="sin(420*2*PI*t):cos(430*2*PI*t)::c=FC|BC"
+@end example
+
+@item
+Generate white noise:
+@example
+aevalsrc="-2+random(0)"
+@end example
+
+@item
+Generate an amplitude modulated signal:
+@example
+aevalsrc="sin(10*2*PI*t)*sin(880*2*PI*t)"
+@end example
+
+@item
+Generate 2.5 Hz binaural beats on a 360 Hz carrier:
+@example
+aevalsrc="0.1*sin(2*PI*(360-2.5/2)*t) : 0.1*sin(2*PI*(360+2.5/2)*t)"
+@end example
+
+@end itemize
+
+@section amovie
+
+Read an audio stream from a movie container.
+
+It accepts the syntax: @var{movie_name}[:@var{options}] where
+@var{movie_name} is the name of the resource to read (not necessarily
+a file but also a device or a stream accessed through some protocol),
+and @var{options} is an optional sequence of @var{key}=@var{value}
+pairs, separated by ":".
+
+The description of the accepted options follows.
+
+@table @option
+
+@item format_name, f
+Specify the format assumed for the movie to read, and can be either
+the name of a container or an input device. If not specified the
+format is guessed from @var{movie_name} or by probing.
+
+@item seek_point, sp
+Specify the seek point in seconds, the frames will be output
+starting from this seek point, the parameter is evaluated with
+@code{av_strtod} so the numerical value may be suffixed by an IS
+postfix. Default value is "0".
+
+@item stream_index, si
+Specify the index of the audio stream to read. If the value is -1,
+the best suited audio stream will be automatically selected. Default
+value is "-1".
+
+@end table
+
@section anullsrc
-Null audio source, never return audio frames. It is mainly useful as a
-template and to be employed in analysis / debugging tools.
+Null audio source, return unprocessed audio frames. It is mainly useful
+as a template and to be employed in analysis / debugging tools, or as
+the source for filters which ignore the input data (for example the sox
+synth filter).
-It accepts as optional parameter a string of the form
-@var{sample_rate}:@var{channel_layout}.
+It accepts an optional sequence of @var{key}=@var{value} pairs,
+separated by ":".
-@var{sample_rate} specify the sample rate, and defaults to 44100.
+The description of the accepted options follows.
-@var{channel_layout} specify the channel layout, and can be either an
-integer or a string representing a channel layout. The default value
-of @var{channel_layout} is 3, which corresponds to CH_LAYOUT_STEREO.
+@table @option
+
+@item sample_rate, s
+Specify the sample rate, and defaults to 44100.
+
+@item channel_layout, cl
+
+Specify the channel layout, and can be either an integer or a string
+representing a channel layout. The default value of @var{channel_layout}
+is "stereo".
Check the channel_layout_map definition in
@file{libavcodec/audioconvert.c} for the mapping between strings and
channel layout values.
+@item nb_samples, n
+Set the number of samples per requested frames.
+
+@end table
+
Follow some examples:
@example
-# set the sample rate to 48000 Hz and the channel layout to CH_LAYOUT_MONO.
-anullsrc=48000:4
+# set the sample rate to 48000 Hz and the channel layout to AV_CH_LAYOUT_MONO.
+anullsrc=r=48000:cl=4
# same as
-anullsrc=48000:mono
+anullsrc=r=48000:cl=mono
@end example
@section abuffer
Below is a description of the currently available audio sinks.
+@section abuffersink
+
+Buffer audio frames, and make them available to the end of filter chain.
+
+This sink is mainly intended for programmatic use, in particular
+through the interface defined in @file{libavfilter/buffersink.h}.
+
+It requires a pointer to an AVABufferSinkContext structure, which
+defines the incoming buffers' formats, to be passed as the opaque
+parameter to @code{avfilter_init_filter} for initialization.
+
@section anullsink
Null audio sink, do absolutely nothing with the input audio. It is
mainly useful as a template and to be employed in analysis / debugging
tools.
-@section abuffersink
-This sink is intended for programmatic use. Frames that arrive on this sink can
-be retrieved by the calling program using the interface defined in
-@file{libavfilter/buffersink.h}.
+@section abuffersink
+This sink is intended for programmatic use. Frames that arrive on this sink can
+be retrieved by the calling program using the interface defined in
+@file{libavfilter/buffersink.h}.
+
+This filter accepts no parameters.
+
+@c man end AUDIO SINKS
+
+@chapter Video Filters
+@c man begin VIDEO FILTERS
+
+When you configure your FFmpeg build, you can disable any of the
+existing filters using @code{--disable-filters}.
+The configure output will show the video filters included in your
+build.
+
+Below is a description of the currently available video filters.
+
+@section ass
+
+Draw ASS (Advanced Substation Alpha) subtitles on top of input video
+using the libass library.
+
+To enable compilation of this filter you need to configure FFmpeg with
+@code{--enable-libass}.
+
+This filter accepts the syntax: @var{ass_filename}[:@var{options}],
+where @var{ass_filename} is the filename of the ASS file to read, and
+@var{options} is an optional sequence of @var{key}=@var{value} pairs,
+separated by ":".
+
+A description of the accepted options follows.
+
+@table @option
+@item original_size
+Specifies the size of the original video, the video for which the ASS file
+was composed. Due to a misdesign in ASS aspect ratio arithmetic, this is
+necessary to correctly scale the fonts if the aspect ratio has been changed.
+@end table
+
+For example, to render the file @file{sub.ass} on top of the input
+video, use the command:
+@example
+ass=sub.ass
+@end example
+
+@section bbox
+
+Compute the bounding box for the non-black pixels in the input frame
+luminance plane.
+
+This filter computes the bounding box containing all the pixels with a
+luminance value greater than the minimum allowed value.
+The parameters describing the bounding box are printed on the filter
+log.
+
+@section blackdetect
+
+Detect video intervals that are (almost) completely black. Can be
+useful to detect chapter transitions, commercials, or invalid
+recordings. Output lines contains the time for the start, end and
+duration of the detected black interval expressed in seconds.
+
+In order to display the output lines, you need to set the loglevel at
+least to the AV_LOG_INFO value.
+
+This filter accepts a list of options in the form of
+@var{key}=@var{value} pairs separated by ":". A description of the
+accepted options follows.
+
+@table @option
+@item black_min_duration, d
+Set the minimum detected black duration expressed in seconds. It must
+be a non-negative floating point number.
+
+Default value is 2.0.
+
+@item picture_black_ratio_th, pic_th
+Set the threshold for considering a picture "black".
+Express the minimum value for the ratio:
+@example
+@var{nb_black_pixels} / @var{nb_pixels}
+@end example
+
+for which a picture is considered black.
+Default value is 0.98.
-This filter accepts no parameters.
+@item pixel_black_th, pix_th
+Set the threshold for considering a pixel "black".
-@c man end AUDIO SINKS
+The threshold expresses the maximum pixel luminance value for which a
+pixel is considered "black". The provided value is scaled according to
+the following equation:
+@example
+@var{absolute_threshold} = @var{luminance_minimum_value} + @var{pixel_black_th} * @var{luminance_range_size}
+@end example
-@chapter Video Filters
-@c man begin VIDEO FILTERS
+@var{luminance_range_size} and @var{luminance_minimum_value} depend on
+the input video format, the range is [0-255] for YUV full-range
+formats and [16-235] for YUV non full-range formats.
-When you configure your Libav build, you can disable any of the
-existing filters using --disable-filters.
-The configure output will show the video filters included in your
-build.
+Default value is 0.10.
+@end table
-Below is a description of the currently available video filters.
+The following example sets the maximum pixel threshold to the minimum
+value, and detects only black intervals of 2 or more seconds:
+@example
+blackdetect=d=2:pix_th=0.00
+@end example
@section blackframe
Apply boxblur algorithm to the input video.
This filter accepts the parameters:
-@var{luma_power}:@var{luma_radius}:@var{chroma_radius}:@var{chroma_power}:@var{alpha_radius}:@var{alpha_power}
+@var{luma_radius}:@var{luma_power}:@var{chroma_radius}:@var{chroma_power}:@var{alpha_radius}:@var{alpha_power}
Chroma and alpha parameters are optional, if not specified they default
to the corresponding values set for @var{luma_radius} and
@end itemize
+@section colormatrix
+
+The colormatrix filter allows conversion between any of the following color
+space: BT.709 (@var{bt709}), BT.601 (@var{bt601}), SMPTE-240M (@var{smpte240m})
+and FCC (@var{fcc}).
+
+The syntax of the parameters is @var{source}:@var{destination}:
+
+@example
+colormatrix=bt601:smpte240m
+@end example
+
@section copy
Copy the input source unchanged to the output. Mainly useful for
@section crop
-Crop the input video to @var{out_w}:@var{out_h}:@var{x}:@var{y}.
+Crop the input video to @var{out_w}:@var{out_h}:@var{x}:@var{y}:@var{keep_aspect}
-The parameters are expressions containing the following constants:
+The @var{keep_aspect} parameter is optional, if specified and set to a
+non-zero value will force the output display aspect ratio to be the
+same of the input, by changing the output sample aspect ratio.
-@table @option
-@item E, PI, PHI
-the corresponding mathematical approximated values for e
-(euler number), pi (greek PI), PHI (golden ratio)
+The @var{out_w}, @var{out_h}, @var{x}, @var{y} parameters are
+expressions containing the following constants:
+@table @option
@item x, y
the computed values for @var{x} and @var{y}. They are evaluated for
each new frame.
@item ow, oh
same as @var{out_w} and @var{out_h}
+@item a
+same as @var{iw} / @var{ih}
+
+@item sar
+input sample aspect ratio
+
+@item dar
+input display aspect ratio, it is the same as (@var{iw} / @var{ih}) * @var{sar}
+
+@item hsub, vsub
+horizontal and vertical chroma subsample values. For example for the
+pixel format "yuv422p" @var{hsub} is 2 and @var{vsub} is 1.
+
@item n
the number of input frame, starting from 0
@end itemize
+@section deshake
+
+Attempt to fix small changes in horizontal and/or vertical shift. This
+filter helps remove camera shake from hand-holding a camera, bumping a
+tripod, moving on a vehicle, etc.
+
+The filter accepts parameters as a string of the form
+"@var{x}:@var{y}:@var{w}:@var{h}:@var{rx}:@var{ry}:@var{edge}:@var{blocksize}:@var{contrast}:@var{search}:@var{filename}"
+
+A description of the accepted parameters follows.
+
+@table @option
+
+@item x, y, w, h
+Specify a rectangular area where to limit the search for motion
+vectors.
+If desired the search for motion vectors can be limited to a
+rectangular area of the frame defined by its top left corner, width
+and height. These parameters have the same meaning as the drawbox
+filter which can be used to visualise the position of the bounding
+box.
+
+This is useful when simultaneous movement of subjects within the frame
+might be confused for camera motion by the motion vector search.
+
+If any or all of @var{x}, @var{y}, @var{w} and @var{h} are set to -1
+then the full frame is used. This allows later options to be set
+without specifying the bounding box for the motion vector search.
+
+Default - search the whole frame.
+
+@item rx, ry
+Specify the maximum extent of movement in x and y directions in the
+range 0-64 pixels. Default 16.
+
+@item edge
+Specify how to generate pixels to fill blanks at the edge of the
+frame. An integer from 0 to 3 as follows:
+@table @option
+@item 0
+Fill zeroes at blank locations
+@item 1
+Original image at blank locations
+@item 2
+Extruded edge value at blank locations
+@item 3
+Mirrored edge at blank locations
+@end table
+
+The default setting is mirror edge at blank locations.
+
+@item blocksize
+Specify the blocksize to use for motion search. Range 4-128 pixels,
+default 8.
+
+@item contrast
+Specify the contrast threshold for blocks. Only blocks with more than
+the specified contrast (difference between darkest and lightest
+pixels) will be considered. Range 1-255, default 125.
+
+@item search
+Specify the search strategy 0 = exhaustive search, 1 = less exhaustive
+search. Default - exhaustive search.
+
+@item filename
+If set then a detailed log of the motion search is written to the
+specified file.
+
+@end table
+
@section drawbox
Draw a colored box on the input image.
Draw text string or text from specified file on top of video using the
libfreetype library.
-To enable compilation of this filter you need to configure Libav with
+To enable compilation of this filter you need to configure FFmpeg with
@code{--enable-libfreetype}.
The filter also recognizes strftime() sequences in the provided text
@table @option
-@item fontfile
-The font file to be used for drawing text. Path must be included.
-This parameter is mandatory.
-
-@item text
-The text string to be drawn. The text must be a sequence of UTF-8
-encoded characters.
-This parameter is mandatory if no file is specified with the parameter
-@var{textfile}.
-
-@item textfile
-A text file containing text to be drawn. The text must be a sequence
-of UTF-8 encoded characters.
-
-This parameter is mandatory if no text string is specified with the
-parameter @var{text}.
-
-If both text and textfile are specified, an error is thrown.
-
-@item x, y
-The offsets where text will be drawn within the video frame.
-Relative to the top/left border of the output image.
-They accept expressions similar to the @ref{overlay} filter:
-@table @option
-
-@item x, y
-the computed values for @var{x} and @var{y}. They are evaluated for
-each new frame.
-
-@item main_w, main_h
-main input width and height
-
-@item W, H
-same as @var{main_w} and @var{main_h}
-
-@item text_w, text_h
-rendered text width and height
-
-@item w, h
-same as @var{text_w} and @var{text_h}
+@item box
+Used to draw a box around text using background color.
+Value should be either 1 (enable) or 0 (disable).
+The default value of @var{box} is 0.
-@item n
-the number of frames processed, starting from 0
+@item boxcolor
+The color to be used for drawing box around text.
+Either a string (e.g. "yellow") or in 0xRRGGBB[AA] format
+(e.g. "0xff00ff"), possibly followed by an alpha specifier.
+The default value of @var{boxcolor} is "white".
-@item t
-timestamp expressed in seconds, NAN if the input timestamp is unknown
+@item draw
+Set an expression which specifies if the text should be drawn. If the
+expression evaluates to 0, the text is not drawn. This is useful for
+specifying that the text should be drawn only when specific conditions
+are met.
-@end table
+Default value is "1".
-The default value of @var{x} and @var{y} is 0.
+See below for the list of accepted constants and functions.
-@item fontsize
-The font size to be used for drawing text.
-The default value of @var{fontsize} is 16.
+@item fix_bounds
+If true, check and fix text coords to avoid clipping.
@item fontcolor
The color to be used for drawing fonts.
(e.g. "0xff000033"), possibly followed by an alpha specifier.
The default value of @var{fontcolor} is "black".
-@item boxcolor
-The color to be used for drawing box around text.
-Either a string (e.g. "yellow") or in 0xRRGGBB[AA] format
-(e.g. "0xff00ff"), possibly followed by an alpha specifier.
-The default value of @var{boxcolor} is "white".
-
-@item box
-Used to draw a box around text using background color.
-Value should be either 1 (enable) or 0 (disable).
-The default value of @var{box} is 0.
-
-@item shadowx, shadowy
-The x and y offsets for the text shadow position with respect to the
-position of the text. They can be either positive or negative
-values. Default value for both is "0".
+@item fontfile
+The font file to be used for drawing text. Path must be included.
+This parameter is mandatory.
-@item shadowcolor
-The color to be used for drawing a shadow behind the drawn text. It
-can be a color name (e.g. "yellow") or a string in the 0xRRGGBB[AA]
-form (e.g. "0xff00ff"), possibly followed by an alpha specifier.
-The default value of @var{shadowcolor} is "black".
+@item fontsize
+The font size to be used for drawing text.
+The default value of @var{fontsize} is 16.
@item ft_load_flags
Flags to be used for loading the fonts.
For more information consult the documentation for the FT_LOAD_*
libfreetype flags.
+@item shadowcolor
+The color to be used for drawing a shadow behind the drawn text. It
+can be a color name (e.g. "yellow") or a string in the 0xRRGGBB[AA]
+form (e.g. "0xff00ff"), possibly followed by an alpha specifier.
+The default value of @var{shadowcolor} is "black".
+
+@item shadowx, shadowy
+The x and y offsets for the text shadow position with respect to the
+position of the text. They can be either positive or negative
+values. Default value for both is "0".
+
@item tabsize
The size in number of spaces to use for rendering the tab.
Default value is 4.
-@item fix_bounds
-If true, check and fix text coords to avoid clipping.
+@item timecode
+Set the initial timecode representation in "hh:mm:ss[:;.]ff"
+format. It can be used with or without text parameter. @var{timecode_rate}
+option must be specified.
+
+@item timecode_rate, rate, r
+Set the timecode frame rate (timecode only).
+
+@item text
+The text string to be drawn. The text must be a sequence of UTF-8
+encoded characters.
+This parameter is mandatory if no file is specified with the parameter
+@var{textfile}.
+
+@item textfile
+A text file containing text to be drawn. The text must be a sequence
+of UTF-8 encoded characters.
+
+This parameter is mandatory if no text string is specified with the
+parameter @var{text}.
+
+If both @var{text} and @var{textfile} are specified, an error is thrown.
+
+@item x, y
+The expressions which specify the offsets where text will be drawn
+within the video frame. They are relative to the top/left border of the
+output image.
+
+The default value of @var{x} and @var{y} is "0".
+
+See below for the list of accepted constants and functions.
+@end table
+
+The parameters for @var{x} and @var{y} are expressions containing the
+following constants and functions:
+
+@table @option
+@item dar
+input display aspect ratio, it is the same as (@var{w} / @var{h}) * @var{sar}
+
+@item hsub, vsub
+horizontal and vertical chroma subsample values. For example for the
+pixel format "yuv422p" @var{hsub} is 2 and @var{vsub} is 1.
+
+@item line_h, lh
+the height of each text line
+
+@item main_h, h, H
+the input height
+
+@item main_w, w, W
+the input width
+
+@item max_glyph_a, ascent
+the maximum distance from the baseline to the highest/upper grid
+coordinate used to place a glyph outline point, for all the rendered
+glyphs.
+It is a positive value, due to the grid's orientation with the Y axis
+upwards.
+
+@item max_glyph_d, descent
+the maximum distance from the baseline to the lowest grid coordinate
+used to place a glyph outline point, for all the rendered glyphs.
+This is a negative value, due to the grid's orientation, with the Y axis
+upwards.
+
+@item max_glyph_h
+maximum glyph height, that is the maximum height for all the glyphs
+contained in the rendered text, it is equivalent to @var{ascent} -
+@var{descent}.
+
+@item max_glyph_w
+maximum glyph width, that is the maximum width for all the glyphs
+contained in the rendered text
+
+@item n
+the number of input frame, starting from 0
+
+@item rand(min, max)
+return a random number included between @var{min} and @var{max}
+
+@item sar
+input sample aspect ratio
+
+@item t
+timestamp expressed in seconds, NAN if the input timestamp is unknown
+
+@item text_h, th
+the height of the rendered text
+
+@item text_w, tw
+the width of the rendered text
+
+@item x, y
+the x and y offset coordinates where the text is drawn.
+
+These parameters allow the @var{x} and @var{y} expressions to refer
+each other, so you can for example specify @code{y=x/dar}.
@end table
-For example the command:
+If libavfilter was built with @code{--enable-fontconfig}, then
+@option{fontfile} can be a fontconfig pattern or omitted.
+
+Some examples follow.
+
+@itemize
+
+@item
+Draw "Test Text" with font FreeSerif, using the default values for the
+optional parameters.
+
@example
drawtext="fontfile=/usr/share/fonts/truetype/freefont/FreeSerif.ttf: text='Test Text'"
@end example
-will draw "Test Text" with font FreeSerif, using the default values
-for the optional parameters.
+@item
+Draw 'Test Text' with font FreeSerif of size 24 at position x=100
+and y=50 (counting from the top-left corner of the screen), text is
+yellow with a red box around it. Both the text and the box have an
+opacity of 20%.
-The command:
@example
drawtext="fontfile=/usr/share/fonts/truetype/freefont/FreeSerif.ttf: text='Test Text':\
x=100: y=50: fontsize=24: fontcolor=yellow@@0.2: box=1: boxcolor=red@@0.2"
@end example
-will draw 'Test Text' with font FreeSerif of size 24 at position x=100
-and y=50 (counting from the top-left corner of the screen), text is
-yellow with a red box around it. Both the text and the box have an
-opacity of 20%.
-
Note that the double quotes are not necessary if spaces are not used
within the parameter list.
+@item
+Show the text at the center of the video frame:
+@example
+drawtext="fontsize=30:fontfile=FreeSerif.ttf:text='hello world':x=(w-text_w)/2:y=(h-text_h-line_h)/2"
+@end example
+
+@item
+Show a text line sliding from right to left in the last row of the video
+frame. The file @file{LONG_LINE} is assumed to contain a single line
+with no newlines.
+@example
+drawtext="fontsize=15:fontfile=FreeSerif.ttf:text=LONG_LINE:y=h-line_h:x=-50*t"
+@end example
+
+@item
+Show the content of file @file{CREDITS} off the bottom of the frame and scroll up.
+@example
+drawtext="fontsize=20:fontfile=FreeSerif.ttf:textfile=CREDITS:y=h-20*t"
+@end example
+
+@item
+Draw a single green letter "g", at the center of the input video.
+The glyph baseline is placed at half screen height.
+@example
+drawtext="fontsize=60:fontfile=FreeSerif.ttf:fontcolor=green:text=g:x=(w-max_glyph_w)/2:y=h/2-ascent"
+@end example
+
+@item
+Show text for 1 second every 3 seconds:
+@example
+drawtext="fontfile=FreeSerif.ttf:fontcolor=white:x=100:y=x/dar:draw=lt(mod(t\\,3)\\,1):text='blink'"
+@end example
+
+@item
+Use fontconfig to set the font. Note that the colons need to be escaped.
+@example
+drawtext='fontfile=Linux Libertine O-40\\:style=Semibold:text=FFmpeg'
+@end example
+
+@end itemize
+
For more information about libfreetype, check:
@url{http://www.freetype.org/}.
+For more information about fontconfig, check:
+@url{http://freedesktop.org/software/fontconfig/fontconfig-user.html}.
+
@section fade
Apply fade-in/out effect to input video.
It accepts the parameters:
-@var{type}:@var{start_frame}:@var{nb_frames}
+@var{type}:@var{start_frame}:@var{nb_frames}[:@var{options}]
@var{type} specifies if the effect type, can be either "in" for
fade-in, or "out" for a fade-out effect.
@var{start_frame} specifies the number of the start frame for starting
to apply the fade effect.
-@var{nb_frames} specifies the number of frames for which the fade
-effect has to last. At the end of the fade-in effect the output video
-will have the same intensity as the input video, at the end of the
-fade-out transition the output video will be completely black.
+@var{nb_frames} specifies the number of frames for which the fade
+effect has to last. At the end of the fade-in effect the output video
+will have the same intensity as the input video, at the end of the
+fade-out transition the output video will be completely black.
+
+@var{options} is an optional sequence of @var{key}=@var{value} pairs,
+separated by ":". The description of the accepted options follows.
+
+@table @option
+
+@item type, t
+See @var{type}.
+
+@item start_frame, s
+See @var{start_frame}.
+
+@item nb_frames, n
+See @var{nb_frames}.
+
+@item alpha
+If set to 1, fade only alpha channel, if one exists on the input.
+Default value is 0.
+@end table
A few usage examples follow, usable too as test scenarios.
@example
# make first 5 frames black, then fade in from frame 5-24
fade=in:5:20
+
+# fade in alpha over first 25 frames of video
+fade=in:0:25:alpha=1
@end example
@section fieldorder
For example:
@example
-./avconv -i in.vob -vf "fieldorder=bff" out.dv
+ffmpeg -i in.vob -vf "fieldorder=bff" out.dv
@end example
@section fifo
Apply a frei0r effect to the input video.
To enable compilation of this filter you need to install the frei0r
-header and configure Libav with --enable-frei0r.
+header and configure FFmpeg with @code{--enable-frei0r}.
The filter supports the syntax:
@example
@section gradfun
Fix the banding artifacts that are sometimes introduced into nearly flat
-regions by truncation to 8bit colordepth.
+regions by truncation to 8bit color depth.
Interpolate the gradients that should go where the bands are, and
dither them.
Flip the input video horizontally.
-For example to horizontally flip the input video with @command{avconv}:
+For example to horizontally flip the input video with @command{ffmpeg}:
@example
-avconv -i in.avi -vf "hflip" out.avi
+ffmpeg -i in.avi -vf "hflip" out.avi
@end example
@section hqdn3d
@var{luma_tmp}*@var{chroma_spatial}/@var{luma_spatial}
@end table
+@section idet
+
+Interlaceing detect filter. This filter tries to detect if the input is
+interlaced or progressive. Top or bottom field first.
+
@section lut, lutrgb, lutyuv
Compute a look-up table for binding each pixel component input value
The @var{lut} filter requires either YUV or RGB pixel formats in
input, and accepts the options:
@table @option
-@var{c0} (first pixel component)
-@var{c1} (second pixel component)
-@var{c2} (third pixel component)
-@var{c3} (fourth pixel component, corresponds to the alpha component)
+@item c0
+first pixel component
+@item c1
+second pixel component
+@item c2
+third pixel component
+@item c3
+fourth pixel component, corresponds to the alpha component
@end table
The exact component associated to each option depends on the format in
The @var{lutrgb} filter requires RGB pixel formats in input, and
accepts the options:
@table @option
-@var{r} (red component)
-@var{g} (green component)
-@var{b} (blue component)
-@var{a} (alpha component)
+@item r
+red component
+@item g
+green component
+@item b
+blue component
+@item a
+alpha component
@end table
The @var{lutyuv} filter requires YUV pixel formats in input, and
accepts the options:
@table @option
-@var{y} (Y/luminance component)
-@var{u} (U/Cb component)
-@var{v} (V/Cr component)
-@var{a} (alpha component)
+@item y
+Y/luminance component
+@item u
+U/Cb component
+@item v
+V/Cr component
+@item a
+alpha component
@end table
The expressions can contain the following constants and functions:
@table @option
-@item E, PI, PHI
-the corresponding mathematical approximated values for e
-(euler number), pi (greek PI), PHI (golden ratio)
-
@item w, h
the input width and height
lutyuv="y=negval:u=negval:v=negval"
# negate luminance
-lutyuv=negval
+lutyuv=y=negval
# remove chroma components, turns the video into a graytone image
lutyuv="u=128:v=128"
lutyuv=y=gammaval(0.5)
@end example
+@section mp
+
+Apply an MPlayer filter to the input video.
+
+This filter provides a wrapper around most of the filters of
+MPlayer/MEncoder.
+
+This wrapper is considered experimental. Some of the wrapped filters
+may not work properly and we may drop support for them, as they will
+be implemented natively into FFmpeg. Thus you should avoid
+depending on them when writing portable scripts.
+
+The filters accepts the parameters:
+@var{filter_name}[:=]@var{filter_params}
+
+@var{filter_name} is the name of a supported MPlayer filter,
+@var{filter_params} is a string containing the parameters accepted by
+the named filter.
+
+The list of the currently supported filters follows:
+@table @var
+@item decimate
+@item denoise3d
+@item detc
+@item dint
+@item divtc
+@item down3dright
+@item dsize
+@item eq2
+@item eq
+@item field
+@item fil
+@item fixpts
+@item framestep
+@item fspp
+@item geq
+@item harddup
+@item hqdn3d
+@item hue
+@item il
+@item ilpack
+@item ivtc
+@item kerndeint
+@item mcdeint
+@item noise
+@item ow
+@item palette
+@item perspective
+@item phase
+@item pp7
+@item pullup
+@item qp
+@item rectangle
+@item rotate
+@item sab
+@item smartblur
+@item softpulldown
+@item softskip
+@item spp
+@item telecine
+@item tile
+@item tinterlace
+@item unsharp
+@item uspp
+@item yuvcsp
+@item yvu9
+@end table
+
+The parameter syntax and behavior for the listed filters are the same
+of the corresponding MPlayer filters. For detailed instructions check
+the "VIDEO FILTERS" section in the MPlayer manual.
+
+Some examples follow:
+@example
+# adjust gamma, brightness, contrast
+mp=eq2=1.0:2:0.5
+
+# tweak hue and saturation
+mp=hue=100:-10
+@end example
+
+See also mplayer(1), @url{http://www.mplayerhq.hu/}.
+
@section negate
Negate input video.
This filter accepts an integer in input, if non-zero it negates the
alpha component (if available). The default value in input is 0.
+@section noformat
+
Force libavfilter not to use any of the specified pixel formats for the
input to the next filter.
Apply video transform using libopencv.
To enable this filter install libopencv library and headers and
-configure Libav with --enable-libopencv.
+configure FFmpeg with @code{--enable-libopencv}.
The filter takes the parameters: @var{filter_name}@{:=@}@var{filter_params}.
It takes two inputs and one output, the first input is the "main"
video on which the second input is overlayed.
-It accepts the parameters: @var{x}:@var{y}.
+It accepts the parameters: @var{x}:@var{y}[:@var{options}].
@var{x} is the x coordinate of the overlayed video on the main video,
-@var{y} is the y coordinate. The parameters are expressions containing
+@var{y} is the y coordinate. @var{x} and @var{y} are expressions containing
the following parameters:
@table @option
same as @var{overlay_w} and @var{overlay_h}
@end table
+@var{options} is an optional list of @var{key}=@var{value} pairs,
+separated by ":".
+
+The description of the accepted options follows.
+
+@table @option
+@item rgb
+If set to 1, force the filter to accept inputs in the RGB
+color space. Default value is 0.
+@end table
+
Be aware that frames are taken from each input video in timestamp
order, hence, if their initial timestamps differ, it is a a good idea
to pass the two inputs through a @var{setpts=PTS-STARTPTS} filter to
overlay=main_w-overlay_w-10:main_h-overlay_h-10
# insert a transparent PNG logo in the bottom left corner of the input
-avconv -i input -i logo -filter_complex 'overlay=10:main_h-overlay_h-10' output
+ffmpeg -i input -i logo -filter_complex 'overlay=10:main_h-overlay_h-10' output
# insert 2 different transparent PNG logos (second logo on bottom
# right corner):
-avconv -i input -i logo1 -i logo2 -filter_complex
+ffmpeg -i input -i logo1 -i logo2 -filter_complex
'overlay=10:H-h-10,overlay=W-w-10:H-h-10' output
# add a transparent color layer on top of the main video,
expressions containing the following constants:
@table @option
-@item E, PI, PHI
-the corresponding mathematical approximated values for e
-(euler number), pi (greek PI), phi (golden ratio)
-
@item in_w, in_h
the input video width and height
expressions, or NAN if not yet specified
@item a
-input display aspect ratio, same as @var{iw} / @var{ih}
+same as @var{iw} / @var{ih}
+
+@item sar
+input sample aspect ratio
+
+@item dar
+input display aspect ratio, it is the same as (@var{iw} / @var{ih}) * @var{sar}
@item hsub, vsub
horizontal and vertical chroma subsample values. For example for the
# pad the input to get a final w/h ratio of 16:9
pad="ih*16/9:ih:(ow-iw)/2:(oh-ih)/2"
+# for anamorphic video, in order to set the output display aspect ratio,
+# it is necessary to use sar in the expression, according to the relation:
+# (ih * X / ih) * sar = output_dar
+# X = output_dar / sar
+pad="ih*16/9/sar:ih:(ow-iw)/2:(oh-ih)/2"
+
# double output size and put the input video in the bottom-right
# corner of the output padded area
pad="2*iw:2*ih:ow-iw:oh-ih"
can be used to test the monowhite pixel format descriptor definition.
+@section removelogo
+
+Suppress a TV station logo, using an image file to determine which
+pixels comprise the logo. It works by filling in the pixels that
+comprise the logo with neighboring pixels.
+
+This filter requires one argument which specifies the filter bitmap
+file, which can be any image format supported by libavformat. The
+width and height of the image file must match those of the video
+stream being processed.
+
+Pixels in the provided bitmap image with a value of zero are not
+considered part of the logo, non-zero pixels are considered part of
+the logo. If you use white (255) for the logo and black (0) for the
+rest, you will be safe. For making the filter bitmap, it is
+recommended to take a screen capture of a black frame with the logo
+visible, and then using a threshold filter followed by the erode
+filter once or twice.
+
+If needed, little splotches can be fixed manually. Remember that if
+logo pixels are not covered, the filter quality will be much
+reduced. Marking too many pixels as part of the logo does not hurt as
+much, but it will increase the amount of blurring needed to cover over
+the image and will destroy more information than necessary, and extra
+pixels will slow things down on a large logo.
+
@section scale
-Scale the input video to @var{width}:@var{height} and/or convert the image format.
+Scale the input video to @var{width}:@var{height}[:@var{interl}=@{1|-1@}] and/or convert the image format.
+
+The scale filter forces the output display aspect ratio to be the same
+of the input, by changing the output sample aspect ratio.
The parameters @var{width} and @var{height} are expressions containing
the following constants:
@table @option
-@item E, PI, PHI
-the corresponding mathematical approximated values for e
-(euler number), pi (greek PI), phi (golden ratio)
-
@item in_w, in_h
the input width and height
@item ow, oh
same as @var{out_w} and @var{out_h}
-@item dar, a
-input display aspect ratio, same as @var{iw} / @var{ih}
+@item a
+same as @var{iw} / @var{ih}
@item sar
input sample aspect ratio
+@item dar
+input display aspect ratio, it is the same as (@var{iw} / @var{ih}) * @var{sar}
+
@item hsub, vsub
horizontal and vertical chroma subsample values. For example for the
pixel format "yuv422p" @var{hsub} is 2 and @var{vsub} is 1.
The default value of @var{width} and @var{height} is 0.
+Valid values for the optional parameter @var{interl} are:
+
+@table @option
+@item 1
+force interlaced aware scaling
+
+@item -1
+select interlaced aware scaling depending on whether the source frames
+are flagged as interlaced or not
+@end table
+
+Unless @var{interl} is set to one of the above options, interlaced scaling will not be used.
+
Some examples follow:
@example
# scale the input video to a size of 200x100.
# the above is the same as
scale=2*in_w:2*in_h
+# scale the input to 2x with forced interlaced scaling
+scale=2*iw:2*ih:interl=1
+
# scale the input to half size
scale=iw/2:ih/2
The expression can contain the following constants:
@table @option
-@item PI
-Greek PI
-
-@item PHI
-golden ratio
-
-@item E
-Euler number
-
@item n
the sequential number of the filtered frame, starting from 0
select='isnan(prev_selected_t)+gte(t-prev_selected_t\,10)'
@end example
-@anchor{setdar}
-@section setdar
+@section setdar, setsar
-Set the Display Aspect Ratio for the filter output video.
+The @code{setdar} filter sets the Display Aspect Ratio for the filter
+output video.
This is done by changing the specified Sample (aka Pixel) Aspect
Ratio, according to the following equation:
-@math{DAR = HORIZONTAL_RESOLUTION / VERTICAL_RESOLUTION * SAR}
+@example
+@var{DAR} = @var{HORIZONTAL_RESOLUTION} / @var{VERTICAL_RESOLUTION} * @var{SAR}
+@end example
+
+Keep in mind that the @code{setdar} filter does not modify the pixel
+dimensions of the video frame. Also the display aspect ratio set by
+this filter may be changed by later filters in the filterchain,
+e.g. in case of scaling or if another "setdar" or a "setsar" filter is
+applied.
+
+The @code{setsar} filter sets the Sample (aka Pixel) Aspect Ratio for
+the filter output video.
-Keep in mind that this filter does not modify the pixel dimensions of
-the video frame. Also the display aspect ratio set by this filter may
-be changed by later filters in the filterchain, e.g. in case of
-scaling or if another "setdar" or a "setsar" filter is applied.
+Note that as a consequence of the application of this filter, the
+output display aspect ratio will change according to the equation
+above.
+
+Keep in mind that the sample aspect ratio set by the @code{setsar}
+filter may be changed by later filters in the filterchain, e.g. if
+another "setsar" or a "setdar" filter is applied.
-The filter accepts a parameter string which represents the wanted
-display aspect ratio.
-The parameter can be a floating point number string, or an expression
-of the form @var{num}:@var{den}, where @var{num} and @var{den} are the
-numerator and denominator of the aspect ratio.
-If the parameter is not specified, it is assumed the value "0:1".
+The @code{setdar} and @code{setsar} filters accept a parameter string
+which represents the wanted aspect ratio. The parameter can
+be a floating point number string, an expression, or a string of the form
+@var{num}:@var{den}, where @var{num} and @var{den} are the numerator
+and denominator of the aspect ratio. If the parameter is not
+specified, it is assumed the value "0:1".
For example to change the display aspect ratio to 16:9, specify:
@example
setdar=16:9
-# the above is equivalent to
+@end example
+
+The example above is equivalent to:
+@example
setdar=1.77777
@end example
-See also the @ref{setsar} filter documentation.
+To change the sample aspect ratio to 10:11, specify:
+@example
+setsar=10:11
+@end example
+
+@section setfield
+
+Force field for the output video frame.
+
+The @code{setfield} filter marks the interlace type field for the
+output frames. It does not change the input frame, but only sets the
+corresponding property, which affects how the frame is treated by
+following filters (e.g. @code{fieldorder} or @code{yadif}).
+
+It accepts a string parameter, which can assume the following values:
+@table @samp
+@item auto
+Keep the same field property.
+
+@item bff
+Mark the frame as bottom-field-first.
+
+@item tff
+Mark the frame as top-field-first.
+
+@item prog
+Mark the frame as progressive.
+@end table
@section setpts
@item PTS
the presentation timestamp in input
-@item PI
-Greek PI
-
-@item PHI
-golden ratio
-
-@item E
-Euler number
-
@item N
the count of the input frame, starting from 0.
setpts='1/(25*TB) * (N + 0.05 * sin(N*2*PI/25))'
@end example
-@anchor{setsar}
-@section setsar
-
-Set the Sample (aka Pixel) Aspect Ratio for the filter output video.
-
-Note that as a consequence of the application of this filter, the
-output display aspect ratio will change according to the following
-equation:
-@math{DAR = HORIZONTAL_RESOLUTION / VERTICAL_RESOLUTION * SAR}
-
-Keep in mind that the sample aspect ratio set by this filter may be
-changed by later filters in the filterchain, e.g. if another "setsar"
-or a "setdar" filter is applied.
-
-The filter accepts a parameter string which represents the wanted
-sample aspect ratio.
-The parameter can be a floating point number string, or an expression
-of the form @var{num}:@var{den}, where @var{num} and @var{den} are the
-numerator and denominator of the aspect ratio.
-If the parameter is not specified, it is assumed the value "0:1".
-
-For example to change the sample aspect ratio to 10:11, specify:
-@example
-setsar=10:11
-@end example
-
@section settb
Set the timebase to use for the output frames timestamps.
It is mainly useful for testing timebase configuration.
It accepts in input an arithmetic expression representing a rational.
-The expression can contain the constants "PI", "E", "PHI", "AVTB" (the
+The expression can contain the constants "AVTB" (the
default timebase), and "intb" (the input timebase).
The default value for the input is "intb".
@file{libavutil/avutil.h}.
@item checksum
-Adler-32 checksum of all the planes of the input frame
+Adler-32 checksum (printed in hexadecimal) of all the planes of the input frame
@item plane_checksum
-Adler-32 checksum of each plane of the input frame, expressed in the form
-"[@var{c0} @var{c1} @var{c2} @var{c3}]"
+Adler-32 checksum (printed in hexadecimal) of each plane of the input frame,
+expressed in the form "[@var{c0} @var{c1} @var{c2} @var{c3}]"
@end table
@section slicify
slices.
@example
-./avconv -i in.avi -vf "slicify=32" out.avi
+ffmpeg -i in.avi -vf "slicify=32" out.avi
@end example
The filter accepts the slice height as parameter. If the parameter is
For example
@example
-avconv -i INPUT -filter_complex split=5 OUTPUT
+ffmpeg -i INPUT -filter_complex split=5 OUTPUT
@end example
will create 5 copies of the input video.
+For example:
+@example
+[in] split [splitout1][splitout2];
+[splitout1] crop=100:100:0:0 [cropout];
+[splitout2] pad=200:200:100:100 [padout];
+@end example
+
+will create two separate outputs from the same input, one cropped and
+one padded.
+
+@section super2xsai
+
+Scale the input by 2x and smooth using the Super2xSaI (Scale and
+Interpolate) pixel art scaling algorithm.
+
+Useful for enlarging pixel art images without reducing sharpness.
+
+@section swapuv
+Swap U & V plane.
+
+@section thumbnail
+Select the most representative frame in a given sequence of consecutive frames.
+
+It accepts as argument the frames batch size to analyze (default @var{N}=100);
+in a set of @var{N} frames, the filter will pick one of them, and then handle
+the next batch of @var{N} frames until the end.
+
+Since the filter keeps track of the whole frames sequence, a bigger @var{N}
+value will result in a higher memory usage, so a high value is not recommended.
+
+The following example extract one picture each 50 frames:
+@example
+thumbnail=50
+@end example
+
+Complete example of a thumbnail creation with @command{ffmpeg}:
+@example
+ffmpeg -i in.avi -vf thumbnail,scale=300:200 -frames:v 1 out.png
+@end example
+
+@section tile
+
+Tile several successive frames together.
+
+It accepts as argument the tile size (i.e. the number of lines and columns)
+in the form "@var{w}x@var{h}".
+
+For example, produce 8×8 PNG tiles of all keyframes (@option{-skip_frame
+nokey}) in a movie:
+@example
+ffmpeg -skip_frame nokey -i file.avi -vf 'scale=128:72,tile=8x8' -an -vsync 0 keyframes%03d.png
+@end example
+The @option{-vsync 0} is necessary to prevent @command{ffmpeg} from
+duplicating each output frame to accomodate the originally detected frame
+rate.
+
+@section tinterlace
+
+Perform various types of temporal field interlacing.
+
+Frames are counted starting from 1, so the first input frame is
+considered odd.
+
+This filter accepts a single parameter specifying the mode. Available
+modes are:
+
+@table @samp
+@item merge, 0
+Move odd frames into the upper field, even into the lower field,
+generating a double height frame at half framerate.
+
+@item drop_odd, 1
+Only output even frames, odd frames are dropped, generating a frame with
+unchanged height at half framerate.
+
+@item drop_even, 2
+Only output odd frames, even frames are dropped, generating a frame with
+unchanged height at half framerate.
+
+@item pad, 3
+Expand each frame to full height, but pad alternate lines with black,
+generating a frame with double height at the same input framerate.
+
+@item interleave_top, 4
+Interleave the upper field from odd frames with the lower field from
+even frames, generating a frame with unchanged height at half framerate.
+
+@item interleave_bottom, 5
+Interleave the lower field from odd frames with the upper field from
+even frames, generating a frame with unchanged height at half framerate.
+
+@item interlacex2, 6
+Double frame rate with unchanged height. Frames are inserted each
+containing the second temporal field from the previous input frame and
+the first temporal field from the next input frame. This mode relies on
+the top_field_first flag. Useful for interlaced video displays with no
+field synchronisation.
+@end table
+
+Numeric values are deprecated but are accepted for backward
+compatibility reasons.
+
+Default mode is @code{merge}.
+
@section transpose
Transpose rows with columns in the input video and optionally flip it.
Set the chroma matrix vertical size. It can be an integer between 3
and 13, default value is 5.
-@item luma_amount
+@item chroma_amount
Set the chroma effect strength. It can be a float number between -2.0
and 5.0, default value is 0.0.
# Strong blur of both luma and chroma parameters
unsharp=7:7:-2:7:7:-2
-# Use the default values with @command{avconv}
-./avconv -i in.avi -vf "unsharp" out.mp4
+# Use the default values with @command{ffmpeg}
+ffmpeg -i in.avi -vf "unsharp" out.mp4
@end example
@section vflip
Flip the input video vertically.
@example
-./avconv -i in.avi -vf "vflip" out.avi
+ffmpeg -i in.avi -vf "vflip" out.avi
@end example
@section yadif
through the interface defined in @file{libavfilter/vsrc_buffer.h}.
It accepts the following parameters:
-@var{width}:@var{height}:@var{pix_fmt_string}:@var{timebase_num}:@var{timebase_den}:@var{sample_aspect_ratio_num}:@var{sample_aspect_ratio.den}
+@var{width}:@var{height}:@var{pix_fmt_string}:@var{timebase_num}:@var{timebase_den}:@var{sample_aspect_ratio_num}:@var{sample_aspect_ratio.den}:@var{scale_params}
-All the parameters need to be explicitly defined.
+All the parameters but @var{scale_params} need to be explicitly
+defined.
Follows the list of the accepted parameters.
@item sample_aspect_ratio.num, sample_aspect_ratio.den
Specify numerator and denominator of the sample aspect ratio assumed
by the video frames.
+
+@item scale_params
+Specify the optional parameters to be used for the scale filter which
+is automatically inserted when an input change is detected in the
+input size or format.
@end table
For example:
(check the enum PixelFormat definition in @file{libavutil/pixfmt.h}),
this example corresponds to:
@example
-buffer=320:240:6:1:24
+buffer=320:240:6:1:24:1:1
+@end example
+
+@section cellauto
+
+Create a pattern generated by an elementary cellular automaton.
+
+The initial state of the cellular automaton can be defined through the
+@option{filename}, and @option{pattern} options. If such options are
+not specified an initial state is created randomly.
+
+At each new frame a new row in the video is filled with the result of
+the cellular automaton next generation. The behavior when the whole
+frame is filled is defined by the @option{scroll} option.
+
+This source accepts a list of options in the form of
+@var{key}=@var{value} pairs separated by ":". A description of the
+accepted options follows.
+
+@table @option
+@item filename, f
+Read the initial cellular automaton state, i.e. the starting row, from
+the specified file.
+In the file, each non-whitespace character is considered an alive
+cell, a newline will terminate the row, and further characters in the
+file will be ignored.
+
+@item pattern, p
+Read the initial cellular automaton state, i.e. the starting row, from
+the specified string.
+
+Each non-whitespace character in the string is considered an alive
+cell, a newline will terminate the row, and further characters in the
+string will be ignored.
+
+@item rate, r
+Set the video rate, that is the number of frames generated per second.
+Default is 25.
+
+@item random_fill_ratio, ratio
+Set the random fill ratio for the initial cellular automaton row. It
+is a floating point number value ranging from 0 to 1, defaults to
+1/PHI.
+
+This option is ignored when a file or a pattern is specified.
+
+@item random_seed, seed
+Set the seed for filling randomly the initial row, must be an integer
+included between 0 and UINT32_MAX. If not specified, or if explicitly
+set to -1, the filter will try to use a good random seed on a best
+effort basis.
+
+@item rule
+Set the cellular automaton rule, it is a number ranging from 0 to 255.
+Default value is 110.
+
+@item size, s
+Set the size of the output video.
+
+If @option{filename} or @option{pattern} is specified, the size is set
+by default to the width of the specified initial state row, and the
+height is set to @var{width} * PHI.
+
+If @option{size} is set, it must contain the width of the specified
+pattern string, and the specified pattern will be centered in the
+larger row.
+
+If a filename or a pattern string is not specified, the size value
+defaults to "320x518" (used for a randomly generated initial state).
+
+@item scroll
+If set to 1, scroll the output upward when all the rows in the output
+have been already filled. If set to 0, the new generated row will be
+written over the top row just after the bottom row is filled.
+Defaults to 1.
+
+@item start_full, full
+If set to 1, completely fill the output with generated rows before
+outputting the first frame.
+This is the default behavior, for disabling set the value to 0.
+
+@item stitch
+If set to 1, stitch the left and right row edges together.
+This is the default behavior, for disabling set the value to 0.
+@end table
+
+@subsection Examples
+
+@itemize
+@item
+Read the initial state from @file{pattern}, and specify an output of
+size 200x400.
+@example
+cellauto=f=pattern:s=200x400
+@end example
+
+@item
+Generate a random initial row with a width of 200 cells, with a fill
+ratio of 2/3:
+@example
+cellauto=ratio=2/3:s=200x200
+@end example
+
+@item
+Create a pattern generated by rule 18 starting by a single alive cell
+centered on an initial row with width 100:
+@example
+cellauto=p=@@:s=100x400:full=0:rule=18
+@end example
+
+@item
+Specify a more elaborated initial pattern:
+@example
+cellauto=p='@@@@ @@ @@@@':s=100x400:full=0:rule=18
@end example
+@end itemize
+
@section color
Provide an uniformly colored input.
the best suited video stream will be automatically selected. Default
value is "-1".
+@item loop
+Specifies how many times to read the video stream in sequence.
+If the value is less than 1, the stream will be read again and again.
+Default value is "1".
+
+Note that when the movie is looped the source timestamps are not
+changed, so it will generate non monotonically increasing timestamps.
@end table
This filter allows to overlay a second video on top of main input of
@end example
-@section nullsrc
+@section mptestsrc
+
+Generate various test patterns, as generated by the MPlayer test filter.
+
+The size of the generated video is fixed, and is 256x256.
+This source is useful in particular for testing encoding features.
+
+This source accepts an optional sequence of @var{key}=@var{value} pairs,
+separated by ":". The description of the accepted options follows.
+
+@table @option
+
+@item rate, r
+Specify the frame rate of the sourced video, as the number of frames
+generated per second. It has to be a string in the format
+@var{frame_rate_num}/@var{frame_rate_den}, an integer number, a float
+number or a valid video frame rate abbreviation. The default value is
+"25".
+
+@item duration, d
+Set the video duration of the sourced video. The accepted syntax is:
+@example
+[-]HH:MM:SS[.m...]
+[-]S+[.m...]
+@end example
+See also the function @code{av_parse_time()}.
+
+If not specified, or the expressed duration is negative, the video is
+supposed to be generated forever.
+
+@item test, t
-Null video source, never return images. It is mainly useful as a
-template and to be employed in analysis / debugging tools.
+Set the number or the name of the test to perform. Supported tests are:
+@table @option
+@item dc_luma
+@item dc_chroma
+@item freq_luma
+@item freq_chroma
+@item amp_luma
+@item amp_chroma
+@item cbp
+@item mv
+@item ring1
+@item ring2
+@item all
+@end table
-It accepts as optional parameter a string of the form
-@var{width}:@var{height}:@var{timebase}.
+Default value is "all", which will cycle through the list of all tests.
+@end table
-@var{width} and @var{height} specify the size of the configured
-source. The default values of @var{width} and @var{height} are
-respectively 352 and 288 (corresponding to the CIF size format).
+For example the following:
+@example
+testsrc=t=dc_luma
+@end example
-@var{timebase} specifies an arithmetic expression representing a
-timebase. The expression can contain the constants "PI", "E", "PHI",
-"AVTB" (the default timebase), and defaults to the value "AVTB".
+will generate a "dc_luma" test pattern.
@section frei0r_src
Provide a frei0r source.
To enable compilation of this filter you need to install the frei0r
-header and configure Libav with --enable-frei0r.
+header and configure FFmpeg with @code{--enable-frei0r}.
The source supports the syntax:
@example
Some examples follow:
@example
-# generate a frei0r partik0l source with size 200x200 and framerate 10
+# generate a frei0r partik0l source with size 200x200 and frame rate 10
# which is overlayed on the overlay filter main input
frei0r_src=200x200:10:partik0l=1234 [overlay]; [in][overlay] overlay
@end example
-@section rgbtestsrc, testsrc
+@section life
+
+Generate a life pattern.
+
+This source is based on a generalization of John Conway's life game.
+
+The sourced input represents a life grid, each pixel represents a cell
+which can be in one of two possible states, alive or dead. Every cell
+interacts with its eight neighbours, which are the cells that are
+horizontally, vertically, or diagonally adjacent.
+
+At each interaction the grid evolves according to the adopted rule,
+which specifies the number of neighbor alive cells which will make a
+cell stay alive or born. The @option{rule} option allows to specify
+the rule to adopt.
+
+This source accepts a list of options in the form of
+@var{key}=@var{value} pairs separated by ":". A description of the
+accepted options follows.
+
+@table @option
+@item filename, f
+Set the file from which to read the initial grid state. In the file,
+each non-whitespace character is considered an alive cell, and newline
+is used to delimit the end of each row.
+
+If this option is not specified, the initial grid is generated
+randomly.
+
+@item rate, r
+Set the video rate, that is the number of frames generated per second.
+Default is 25.
+
+@item random_fill_ratio, ratio
+Set the random fill ratio for the initial random grid. It is a
+floating point number value ranging from 0 to 1, defaults to 1/PHI.
+It is ignored when a file is specified.
+
+@item random_seed, seed
+Set the seed for filling the initial random grid, must be an integer
+included between 0 and UINT32_MAX. If not specified, or if explicitly
+set to -1, the filter will try to use a good random seed on a best
+effort basis.
+
+@item rule
+Set the life rule.
+
+A rule can be specified with a code of the kind "S@var{NS}/B@var{NB}",
+where @var{NS} and @var{NB} are sequences of numbers in the range 0-8,
+@var{NS} specifies the number of alive neighbor cells which make a
+live cell stay alive, and @var{NB} the number of alive neighbor cells
+which make a dead cell to become alive (i.e. to "born").
+"s" and "b" can be used in place of "S" and "B", respectively.
+
+Alternatively a rule can be specified by an 18-bits integer. The 9
+high order bits are used to encode the next cell state if it is alive
+for each number of neighbor alive cells, the low order bits specify
+the rule for "borning" new cells. Higher order bits encode for an
+higher number of neighbor cells.
+For example the number 6153 = @code{(12<<9)+9} specifies a stay alive
+rule of 12 and a born rule of 9, which corresponds to "S23/B03".
+
+Default value is "S23/B3", which is the original Conway's game of life
+rule, and will keep a cell alive if it has 2 or 3 neighbor alive
+cells, and will born a new cell if there are three alive cells around
+a dead cell.
+
+@item size, s
+Set the size of the output video.
+
+If @option{filename} is specified, the size is set by default to the
+same size of the input file. If @option{size} is set, it must contain
+the size specified in the input file, and the initial grid defined in
+that file is centered in the larger resulting area.
+
+If a filename is not specified, the size value defaults to "320x240"
+(used for a randomly generated initial grid).
+
+@item stitch
+If set to 1, stitch the left and right grid edges together, and the
+top and bottom edges also. Defaults to 1.
+
+@item mold
+Set cell mold speed. If set, a dead cell will go from @option{death_color} to
+@option{mold_color} with a step of @option{mold}. @option{mold} can have a
+value from 0 to 255.
+
+@item life_color
+Set the color of living (or new born) cells.
+
+@item death_color
+Set the color of dead cells. If @option{mold} is set, this is the first color
+used to represent a dead cell.
+
+@item mold_color
+Set mold color, for definitely dead and moldy cells.
+@end table
+
+@subsection Examples
+
+@itemize
+@item
+Read a grid from @file{pattern}, and center it on a grid of size
+300x300 pixels:
+@example
+life=f=pattern:s=300x300
+@end example
+
+@item
+Generate a random grid of size 200x200, with a fill ratio of 2/3:
+@example
+life=ratio=2/3:s=200x200
+@end example
+
+@item
+Specify a custom rule for evolving a randomly generated grid:
+@example
+life=rule=S14/B34
+@end example
+
+@item
+Full example with slow death effect (mold) using @command{ffplay}:
+@example
+ffplay -f lavfi life=s=300x200:mold=10:r=60:ratio=0.1:death_color=#C83232:life_color=#00ff00,scale=1200:800:flags=16
+@end example
+@end itemize
+
+@section nullsrc, rgbtestsrc, testsrc
+
+The @code{nullsrc} source returns unprocessed video frames. It is
+mainly useful to be employed in analysis / debugging tools, or as the
+source for filters which ignore the input data.
The @code{rgbtestsrc} source generates an RGB test pattern useful for
detecting RGB vs BGR issues. You should see a red, green and blue
color pattern, a scrolling gradient and a timestamp. This is mainly
intended for testing purposes.
-Both sources accept an optional sequence of @var{key}=@var{value} pairs,
+These sources accept an optional sequence of @var{key}=@var{value} pairs,
separated by ":". The description of the accepted options follows.
@table @option
@item sar
Set the sample aspect ratio of the sourced video.
-@item duration
+@item duration, d
Set the video duration of the sourced video. The accepted syntax is:
@example
[-]HH[:MM[:SS[.m...]]]
If not specified, or the expressed duration is negative, the video is
supposed to be generated forever.
+
+@item decimals, n
+Set the number of decimals to show in the timestamp, only used in the
+@code{testsrc} source.
+
+The displayed timestamp value will correspond to the original
+timestamp value multiplied by the power of 10 of the specified
+value. Default value is 0.
@end table
For example the following:
@end example
will generate a video with a duration of 5.3 seconds, with size
-176x144 and a framerate of 10 frames per second.
+176x144 and a frame rate of 10 frames per second.
+
+If the input content is to be ignored, @code{nullsrc} can be used. The
+following command generates noise in the luminance plane by employing
+the @code{mp=geq} filter:
+@example
+nullsrc=s=256x256, mp=geq=random(1)*255:128:128
+@end example
@c man end VIDEO SOURCES
Buffer video frames, and make them available to the end of the filter
graph.
-This sink is intended for a programmatic use through the interface defined in
-@file{libavfilter/buffersink.h}.
+This sink is mainly intended for a programmatic use, in particular
+through the interface defined in @file{libavfilter/buffersink.h}.
+
+It does not require a string parameter in input, but you need to
+specify a pointer to a list of supported pixel formats terminated by
+-1 in the opaque parameter provided to @code{avfilter_init_filter}
+when initializing this sink.
@section nullsink
projects / ffmpeg / blobdiff