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
+volume (on a per-sample basis), and the beginning of a histogram of the
registered volume values (from the maximum value to a cumulated 1/1000 of
the samples).
@end table
The default is @code{near}.
+@item start_time
+Assume the first PTS should be the given value, in seconds. This allows for
+padding/trimming at the start of stream. By default, no assumption is made
+about the first frame's expected PTS, so no padding or trimming is done.
+For example, this could be set to 0 to pad the beginning with duplicates of
+the first frame if a video stream starts after the audio stream or to trim any
+frames with a negative PTS.
+
@end table
Alternatively, the options can be specified as a flat string:
@item H
Specify the hue angle as a number of radians. It accepts an
expression, and defaults to "0".
+
+@item b
+Specify the brightness in the [-10,10] range. It accepts an expression and
+defaults to "0".
@end table
@option{h} and @option{H} are mutually exclusive, and can't be
specified at the same time.
-The @option{h}, @option{H} and @option{s} option values are
+The @option{b}, @option{h}, @option{H} and @option{s} option values are
expressions containing the following constants:
@table @option
This filter supports the following commands:
@table @option
+@item b
@item s
@item h
@item H
-Modify the hue and/or the saturation of the input video.
+Modify the hue and/or the saturation and/or brightness of the input video.
The command accepts the same syntax of the corresponding option.
If the specified expression is not valid, it is kept at its current
when @option{eval} is set to @samp{init}.
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
+order, hence, if their initial timestamps differ, it is a good idea
to pass the two inputs through a @var{setpts=PTS-STARTPTS} filter to
have them begin in the same zero timestamp, as it does the example for
the @var{movie} filter.
The scale filter forces the output display aspect ratio to be the same
of the input, by changing the output sample aspect ratio.
+If the input image format is different from the format requested by
+the next filter, the scale filter will convert the input to the
+requested format.
+
+@subsection Options
The filter accepts the following options:
@table @option
@item width, w
-Set the output video width expression. Default value is @code{iw}. See
-below for the list of accepted constants.
-
@item height, h
-Set the output video height expression. Default value is @code{ih}.
-See below for the list of accepted constants.
+Set the output video dimension expression. Default value is the input
+dimension.
+
+If the value is 0, the input width is used for the output.
+
+If one of the values is -1, the scale filter will use a value that
+maintains the aspect ratio of the input image, calculated from the
+other specified dimension. If both of them are -1, the input size is
+used
+
+See below for the list of accepted constants for use in the dimension
+expression.
@item interl
-Set the interlacing. It accepts the following values:
+Set the interlacing mode. It accepts the following values:
-@table @option
+@table @samp
@item 1
-force interlaced aware scaling
+Force interlaced aware scaling.
@item 0
-do not apply interlaced scaling
+Do not apply interlaced scaling.
@item -1
-select interlaced aware scaling depending on whether the source frames
-are flagged as interlaced or not
+Select interlaced aware scaling depending on whether the source frames
+are flagged as interlaced or not.
@end table
-Default value is @code{0}.
+Default value is @samp{0}.
@item flags
Set libswscale scaling flags. If not explictly specified the filter
@item in_color_matrix
@item out_color_matrix
-Set in/output YCbCr colorspace type.
+Set in/output YCbCr color space type.
+
This allows the autodetected value to be overridden as well as allows forcing
a specific value used for the output and encoder.
-If not specified, the colorspace type depends on the pixel format.
+
+If not specified, the color space type depends on the pixel format.
+
+Possible values:
+
@table @samp
@item auto
-Choose automatically
+Choose automatically.
@item bt709
-ITU Rec BT709
+Format conforming to International Telecommunication Union (ITU)
+Recommendation BT.709.
@item fcc
-United States Federal Communications Commission Title 47 Code of
-Federal Regulations (2003) 73.682 (a)
+Set color space conforming to the United States Federal Communications
+Commission (FCC) Code of Federal Regulations (CFR) Title 47 (2003) 73.682 (a).
@item bt601
-ITU Rec BT601
-ITU-R Rec. BT.470-6 System B, G
-Society of Motion Picture and Television Engineers 170M (2004)
+Set color space conforming to:
+
+@itemize
+@item
+ITU Radiocommunication Sector (ITU-R) Recommendation BT.601
+
+@item
+ITU-R Rec. BT.470-6 (1998) Systems B, B1, and G
+
+@item
+Society of Motion Picture and Television Engineers (SMPTE) ST 170:2004
+
+@end itemize
@item smpte240m
-Society of Motion Picture and Television Engineers 240M
+Set color space conforming to SMPTE ST 240:1999.
@end table
@item in_range
@item out_range
Set in/output YCbCr sample range.
+
This allows the autodetected value to be overridden as well as allows forcing
-a specific value used for the output and encoder.
-If not specified, the range depends on the pixel format.
+a specific value used for the output and encoder. If not specified, the
+range depends on the pixel format. Possible values:
+
@table @samp
@item auto
-Choose automatically
+Choose automatically.
@item jpeg/full/pc
-Full range (0-255 in case of 8bit luma)
+Set full range (0-255 in case of 8-bit luma).
@item mpeg/tv
-"Mpeg" range (16-235 in case of 8bit luma)
+Set "MPEG" range (16-235 in case of 8-bit luma).
+@end table
+
+@item sws_dither
+Set the dithering algorithm
+
+@table @samp
+@item auto
+Choose automatically.
+
+@item none
+No dithering
+
+@item bayer
+bayer dither
+
+@item ed
+error diffusion dither
@end table
@item force_original_aspect_ratio
@end table
-The values of the @var{w} and @var{h} options are expressions
+The values of the @option{w} and @option{h} options are expressions
containing the following constants:
-@table @option
+@table @var
@item in_w
@item in_h
the input width and height
@item out_w
@item out_h
-the output (cropped) width and height
+the output (scaled) width and height
@item ow
@item oh
input sample aspect ratio
@item dar
-input display aspect ratio, it is the same as (@var{iw} / @var{ih}) * @var{sar}
+input display aspect ratio. Calculated from @code{(iw / ih) * sar}.
@item hsub
@item vsub
pixel format "yuv422p" @var{hsub} is 2 and @var{vsub} is 1.
@end table
-If the input image format is different from the format requested by
-the next filter, the scale filter will convert the input to the
-requested format.
-
-If the value for @var{w} or @var{h} is 0, the respective input
-size is used for the output.
-
-If the value for @var{w} or @var{h} is -1, the scale filter will use, for the
-respective output size, a value that maintains the aspect ratio of the input
-image.
-
@subsection Examples
@itemize
more advanced padding options (such as having different values for the edges),
refer to the pad video filter.
+@item color
+Specify the color of the unused area, it can be the name of a color
+(case insensitive match) or a 0xRRGGBB[AA] sequence.
+The default value of @var{color} is "black".
@end table
@subsection Examples
projects / ffmpeg / blobdiff