@end example
can be used to create and display an image representing the graph
-described by the @var{GRAPH_DESCRIPTION} string.
+described by the @var{GRAPH_DESCRIPTION} string. Note that this string must be
+a complete self-contained graph, with its inputs and outputs explicitly defined.
+For example if your command line is of the form:
+@example
+ffmpeg -i infile -vf scale=640:360 outfile
+@end example
+your @var{GRAPH_DESCRIPTION} string will need to be of the form:
+@example
+nullsrc,scale=640:360,nullsink
+@end example
+you may also need to set the @var{nullsrc} parameters and add a @var{format}
+filter in order to simulate a specific input file.
@c man end GRAPH2DOT
@end example
@end itemize
+@section volumedetect
+
+Detect the volume of the input video.
+
+The filter has no parameters. The input is not modified. Statistics about
+the volume will be printed in the log when the input stream end is reached.
+
+In particular it will show the mean volume (root mean square), maximum
+volume (on a per-sample basis), and the beginning of an histogram of the
+registered volume values (from the maximum value to a cumulated 1/1000 of
+the samples).
+
+All volumes are in decibels relative to the maximum PCM value.
+
+Here is an excerpt of the output:
+@example
+[Parsed_volumedetect_0 @ 0xa23120] mean_volume: -27 dB
+[Parsed_volumedetect_0 @ 0xa23120] max_volume: -4 dB
+[Parsed_volumedetect_0 @ 0xa23120] histogram_4db: 6
+[Parsed_volumedetect_0 @ 0xa23120] histogram_5db: 62
+[Parsed_volumedetect_0 @ 0xa23120] histogram_6db: 286
+[Parsed_volumedetect_0 @ 0xa23120] histogram_7db: 1042
+[Parsed_volumedetect_0 @ 0xa23120] histogram_8db: 2551
+[Parsed_volumedetect_0 @ 0xa23120] histogram_9db: 4609
+[Parsed_volumedetect_0 @ 0xa23120] histogram_10db: 8409
+@end example
+
+It means that:
+@itemize
+@item
+The mean square energy is approximately -27 dB, or 10^-2.7.
+@item
+The largest sample is at -4 dB, or more precisely between -4 dB and -5 dB.
+@item
+There are 6 samples at -4 dB, 62 at -5 dB, 286 at -6 dB, etc.
+@end itemize
+
+In other words, raising the volume by +4 dB does not cause any clipping,
+raising it by +5 dB causes clipping for 6 samples, etc.
+
@section asyncts
Synchronize audio data with timestamps by squeezing/stretching it and/or
dropping samples/adding silence when needed.
@table @option
@item compensate
-Enable stretching/squeezing the data to make it match the timestamps.
+Enable stretching/squeezing the data to make it match the timestamps. Disabled
+by default. When disabled, time gaps are covered with silence.
@item min_delta
Minimum difference between timestamps and audio data (in seconds) to trigger
-adding/dropping samples.
+adding/dropping samples. Default value is 0.1. If you get non-perfect sync with
+this filter, try setting this parameter to 0.
@item max_comp
-Maximum compensation in samples per second.
+Maximum compensation in samples per second. Relevant only with compensate=1.
+Default value 500.
@item first_pts
Assume the first pts should be this value.
@code{kal}. See also the @var{list_voices} option.
@end table
-@section Examples
+@subsection Examples
@itemize
@item
playback.
@end table
+@section decimate
+
+This filter drops frames that do not differ greatly from the previous
+frame in order to reduce framerate. The main use of this filter is
+for very-low-bitrate encoding (e.g. streaming over dialup modem), but
+it could in theory be used for fixing movies that were
+inverse-telecined incorrectly.
+
+It accepts the following parameters:
+@var{max}:@var{hi}:@var{lo}:@var{frac}.
+
+@table @option
+
+@item max
+Set the maximum number of consecutive frames which can be dropped (if
+positive), or the minimum interval between dropped frames (if
+negative). If the value is 0, the frame is dropped unregarding the
+number of previous sequentially dropped frames.
+
+Default value is 0.
+
+@item hi, lo, frac
+Set the dropping threshold values.
+
+Values for @var{hi} and @var{lo} are for 8x8 pixel blocks and
+represent actual pixel value differences, so a threshold of 64
+corresponds to 1 unit of difference for each pixel, or the same spread
+out differently over the block.
+
+A frame is a candidate for dropping if no 8x8 blocks differ by more
+than a threshold of @var{hi}, and if no more than @var{frac} blocks (1
+meaning the whole image) differ by more than a threshold of @var{lo}.
+
+Default value for @var{hi} is 64*12, default value for @var{lo} is
+64*5, and default value for @var{frac} is 0.33.
+@end table
+
@section delogo
Suppress a TV station logo by a simple interpolation of the surrounding
For more information about fontconfig, check:
@url{http://freedesktop.org/software/fontconfig/fontconfig-user.html}.
+@section edgedetect
+
+Detect and draw edges. The filter uses the Canny Edge Detection algorithm.
+
+This filter accepts the following optional named parameters:
+
+@table @option
+@item low, high
+Set low and high threshold values used by the Canny thresholding
+algorithm.
+
+The high threshold selects the "strong" edge pixels, which are then
+connected through 8-connectivity with the "weak" edge pixels selected
+by the low threshold.
+
+@var{low} and @var{high} threshold values must be choosen in the range
+[0,1], and @var{low} should be lesser or equal to @var{high}.
+
+Default value for @var{low} is @code{20/255}, and default value for @var{high}
+is @code{50/255}.
+@end table
+
+Example:
+@example
+edgedetect=low=0.1:high=0.4
+@end example
+
@section fade
Apply fade-in/out effect to input video.
@end table
+@section framestep
+
+Select one frame every N.
+
+This filter accepts in input a string representing a positive
+integer. Default argument is @code{1}.
+
@anchor{frei0r}
@section frei0r
@var{luma_tmp}*@var{chroma_spatial}/@var{luma_spatial}
@end table
+@section hue
+
+Modify the hue and/or the saturation of the input.
+
+This filter accepts the following optional named options:
+
+@table @option
+@item h
+Specify the hue angle as a number of degrees. It accepts a float
+number or an expression, and defaults to 0.0.
+
+@item H
+Specify the hue angle as a number of degrees. It accepts a float
+number or an expression, and defaults to 0.0.
+
+@item s
+Specify the saturation in the [-10,10] range. It accepts a float number and
+defaults to 1.0.
+@end table
+
+The @var{h}, @var{H} and @var{s} parameters are expressions containing the
+following constants:
+
+@table @option
+@item n
+frame count of the input frame starting from 0
+
+@item pts
+presentation timestamp of the input frame expressed in time base units
+
+@item r
+frame rate of the input video, NAN if the input frame rate is unknown
+
+@item t
+timestamp expressed in seconds, NAN if the input timestamp is unknown
+
+@item tb
+time base of the input video
+@end table
+
+The options can also be set using the syntax: @var{hue}:@var{saturation}
+
+In this case @var{hue} is expressed in degrees.
+
+Some examples follow:
+@itemize
+@item
+Set the hue to 90 degrees and the saturation to 1.0:
+@example
+hue=h=90:s=1
+@end example
+
+@item
+Same command but expressing the hue in radians:
+@example
+hue=H=PI/2:s=1
+@end example
+
+@item
+Same command without named options, hue must be expressed in degrees:
+@example
+hue=90:1
+@end example
+
+@item
+Note that "h:s" syntax does not support expressions for the values of
+h and s, so the following example will issue an error:
+@example
+hue=PI/2:1
+@end example
+
+@item
+Rotate hue and make the saturation swing between 0
+and 2 over a period of 1 second:
+@example
+hue="H=2*PI*t: s=sin(2*PI*t)+1"
+@end example
+
+@item
+Apply a 3 seconds saturation fade-in effect starting at 0:
+@example
+hue="s=min(t/3\,1)"
+@end example
+
+The general fade-in expression can be written as:
+@example
+hue="s=min(0\, max((t-START)/DURATION\, 1))"
+@end example
+
+@item
+Apply a 3 seconds saturation fade-out effect starting at 5 seconds:
+@example
+hue="s=max(0\, min(1\, (8-t)/3))"
+@end example
+
+The general fade-out expression can be written as:
+@example
+hue="s=max(0\, min(1\, (START+DURATION-t)/DURATION))"
+@end example
+
+@end itemize
+
+@subsection Commands
+
+This filter supports the following command:
+@table @option
+@item reinit
+Modify the hue and/or the saturation of the input video.
+The command accepts the same named options and syntax than when calling the
+filter from the command-line.
+
+If a parameter is omitted, it is kept at its current value.
+@end table
+
@section idet
Interlaceing detect filter. This filter tries to detect if the input is
The list of the currently supported filters follows:
@table @var
-@item decimate
@item denoise3d
@item detc
@item dint
@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 pullup
@item qp
@item rectangle
-@item rotate
@item sab
-@item smartblur
@item softpulldown
@item softskip
@item spp
the "VIDEO FILTERS" section in the MPlayer manual.
Some examples follow:
+@itemize
+@item
+Adjust gamma, brightness, contrast:
@example
-# adjust gamma, brightness, contrast
mp=eq2=1.0:2:0.5
+@end example
-# tweak hue and saturation
-mp=hue=100:-10
+@item
+Add temporal noise to input video:
+@example
+mp=noise=20t
@end example
+@end itemize
See also mplayer(1), @url{http://www.mplayerhq.hu/}.
@end table
-Some examples follow:
+@section Examples
+@itemize
+@item
+Add paddings with color "violet" to the input video. Output video
+size is 640x480, the top-left corner of the input video is placed at
+column 0, row 40:
@example
-# Add paddings with color "violet" to the input video. Output video
-# size is 640x480, the top-left corner of the input video is placed at
-# column 0, row 40.
pad=640:480:0:40:violet
+@end example
-# pad the input to get an output with dimensions increased bt 3/2,
-# and put the input video at the center of the padded area
+@item
+Pad the input to get an output with dimensions increased by 3/2,
+and put the input video at the center of the padded area:
+@example
pad="3/2*iw:3/2*ih:(ow-iw)/2:(oh-ih)/2"
+@end example
-# pad the input to get a squared output with size equal to the maximum
-# value between the input width and height, and put the input video at
-# the center of the padded area
+@item
+Pad the input to get a squared output with size equal to the maximum
+value between the input width and height, and put the input video at
+the center of the padded area:
+@example
pad="max(iw\,ih):ow:(ow-iw)/2:(oh-ih)/2"
+@end example
-# pad the input to get a final w/h ratio of 16:9
+@item
+Pad the input to get a final w/h ratio of 16:9:
+@example
pad="ih*16/9:ih:(ow-iw)/2:(oh-ih)/2"
+@end example
-# 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
+@item
+In case of anamorphic video, in order to set the output display aspect
+correctly, it is necessary to use @var{sar} in the expression,
+according to the relation:
+@example
+(ih * X / ih) * sar = output_dar
+X = output_dar / sar
+@end example
+
+Thus the previous example needs to be modified to:
+@example
pad="ih*16/9/sar:ih:(ow-iw)/2:(oh-ih)/2"
+@end example
-# double output size and put the input video in the bottom-right
-# corner of the output padded area
+@item
+Double output size and put the input video in the bottom-right
+corner of the output padded area:
+@example
pad="2*iw:2*ih:ow-iw:oh-ih"
@end example
+@end itemize
@section pixdesctest
Mark the frame as progressive.
@end table
-@section asetpts, setpts
-
-Change the PTS (presentation timestamp) of the input frames.
-
-@code{asetpts} works on audio frames, @code{setpts} on video frames.
-
-Accept in input an expression evaluated through the eval API, which
-can contain the following constants:
-
-@table @option
-@item PTS
-the presentation timestamp in input
-
-@item N
-the count of the input frame, starting from 0.
-
-@item NB_CONSUMED_SAMPLES
-the number of consumed samples, not including the current frame (only
-audio)
-
-@item NB_SAMPLES
-the number of samples in the current frame (only audio)
-
-@item SAMPLE_RATE
-audio sample rate
-
-@item STARTPTS
-the PTS of the first video frame
-
-@item INTERLACED
-tell if the current frame is interlaced
-
-@item TB
-the time base
-
-@item POS
-original position in the file of the frame, or undefined if undefined
-for the current frame
-
-@item PREV_INPTS
-previous input PTS
-
-@item PREV_OUTPTS
-previous output PTS
-
-@end table
-
-Some examples follow:
-
-@example
-# start counting PTS from zero
-setpts=PTS-STARTPTS
-
-# fast motion
-setpts=0.5*PTS
-
-# slow motion
-setpts=2.0*PTS
-
-# fixed rate 25 fps
-setpts=N/(25*TB)
-
-# fixed rate 25 fps with some jitter
-setpts='1/(25*TB) * (N + 0.05 * sin(N*2*PI/25))'
-
-# apply an offset of 10 seconds to the input PTS
-setpts=PTS+10/TB
-@end example
-
-@section settb, asettb
-
-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 "AVTB" (the
-default timebase), "intb" (the input timebase) and "sr" (the sample rate,
-audio only).
-
-The default value for the input is "intb".
-
-Follow some examples.
-
-@example
-# set the timebase to 1/25
-settb=1/25
-
-# set the timebase to 1/10
-settb=0.1
-
-#set the timebase to 1001/1000
-settb=1+0.001
-
-#set the timebase to 2*intb
-settb=2*intb
-
-#set the default timebase value
-settb=AVTB
-@end example
-
@section showinfo
Show a line containing various information for each input video frame.
Adding this in the beginning of filter chains should make filtering
faster due to better use of the memory cache.
+@section smartblur
+
+Blur the input video without impacting the outlines.
+
+The filter accepts the following parameters:
+@var{luma_radius}:@var{luma_strength}:@var{luma_threshold}[:@var{chroma_radius}:@var{chroma_strength}:@var{chroma_threshold}]
+
+Parameters prefixed by @var{luma} indicate that they work on the
+luminance of the pixels whereas parameters prefixed by @var{chroma}
+refer to the chrominance of the pixels.
+
+If the chroma parameters are not set, the luma parameters are used for
+either the luminance and the chrominance of the pixels.
+
+@var{luma_radius} or @var{chroma_radius} must be a float number in the
+range [0.1,5.0] that specifies the variance of the gaussian filter
+used to blur the image (slower if larger).
+
+@var{luma_strength} or @var{chroma_strength} must be a float number in
+the range [-1.0,1.0] that configures the blurring. A value included in
+[0.0,1.0] will blur the image whereas a value included in [-1.0,0.0]
+will sharpen the image.
+
+@var{luma_threshold} or @var{chroma_threshold} must be an integer in
+the range [-30,30] that is used as a coefficient to determine whether
+a pixel should be blurred or not. A value of 0 will filter all the
+image, a value included in [0,30] will filter flat areas and a value
+included in [-30,0] will filter edges.
+
@section split
Split input video into several identical outputs.
values:
@table @samp
-@item 0
+@item 0, 4
Rotate by 90 degrees counterclockwise and vertically flip (default), that is:
@example
L.R L.l
l.r R.r
@end example
-@item 1
+@item 1, 5
Rotate by 90 degrees clockwise, that is:
@example
L.R l.L
l.r r.R
@end example
-@item 2
+@item 2, 6
Rotate by 90 degrees counterclockwise, that is:
@example
L.R R.r
l.r L.l
@end example
-@item 3
+@item 3, 7
Rotate by 90 degrees clockwise and vertically flip, that is:
@example
L.R r.R
@end example
@end table
+For values between 4-7 transposition is only done if the input video
+geometry is portrait and not landscape.
+
@section unsharp
Sharpen or blur the input video.
Below is a description of the currently available multimedia filters.
+@section asetpts, setpts
+
+Change the PTS (presentation timestamp) of the input frames.
+
+@code{asetpts} works on audio frames, @code{setpts} on video frames.
+
+Accept in input an expression evaluated through the eval API, which
+can contain the following constants:
+
+@table @option
+@item FRAME_RATE
+frame rate, only defined for constant frame-rate video
+
+@item PTS
+the presentation timestamp in input
+
+@item N
+the count of the input frame, starting from 0.
+
+@item NB_CONSUMED_SAMPLES
+the number of consumed samples, not including the current frame (only
+audio)
+
+@item NB_SAMPLES
+the number of samples in the current frame (only audio)
+
+@item SAMPLE_RATE
+audio sample rate
+
+@item STARTPTS
+the PTS of the first frame
+
+@item STARTT
+the time in seconds of the first frame
+
+@item INTERLACED
+tell if the current frame is interlaced
+
+@item T
+the time in seconds of the current frame
+
+@item TB
+the time base
+
+@item POS
+original position in the file of the frame, or undefined if undefined
+for the current frame
+
+@item PREV_INPTS
+previous input PTS
+
+@item PREV_INT
+previous input time in seconds
+
+@item PREV_OUTPTS
+previous output PTS
+
+@item PREV_OUTT
+previous output time in seconds
+@end table
+
+@subsection Examples
+
+@itemize
+@item
+Start counting PTS from zero
+@example
+setpts=PTS-STARTPTS
+@end example
+
+@item
+Apply fast motion effect:
+@example
+setpts=0.5*PTS
+@end example
+
+@item
+Apply slow motion effect:
+@example
+setpts=2.0*PTS
+@end example
+
+@item
+Set fixed rate of 25 frames per second:
+@example
+setpts=N/(25*TB)
+@end example
+
+@item
+Set fixed rate 25 fps with some jitter:
+@example
+setpts='1/(25*TB) * (N + 0.05 * sin(N*2*PI/25))'
+@end example
+
+@item
+Apply an offset of 10 seconds to the input PTS:
+@example
+setpts=PTS+10/TB
+@end example
+@end itemize
+
+@section settb, asettb
+
+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 "AVTB" (the
+default timebase), "intb" (the input timebase) and "sr" (the sample rate,
+audio only).
+
+The default value for the input is "intb".
+
+@subsection Examples
+
+@itemize
+@item
+Set the timebase to 1/25:
+@example
+settb=1/25
+@end example
+
+@item
+Set the timebase to 1/10:
+@example
+settb=0.1
+@end example
+
+@item
+Set the timebase to 1001/1000:
+@example
+settb=1+0.001
+@end example
+
+@item
+Set the timebase to 2*intb:
+@example
+settb=2*intb
+@end example
+
+@item
+Set the default timebase value:
+@example
+settb=AVTB
+@end example
+@end itemize
+
@section concat
Concatenate audio and video streams, joining them together one after the
@end itemize
+@section showspectrum
+
+Convert input audio to a video output, representing the audio frequency
+spectrum.
+
+The filter accepts the following named parameters:
+@table @option
+@item size, s
+Specify the video size for the output. Default value is @code{640x480}.
+@end table
+
+The usage is very similar to the showwaves filter; see the examples in that
+section.
+
@section showwaves
Convert input audio to a video output, representing the samples waves.
projects / ffmpeg / blobdiff