diff options
author | arwa arif <arwaarif1994@gmail.com> | 2015-03-13 09:16:42 +0300 |
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committer | Stefano Sabatini <stefasab@gmail.com> | 2015-03-20 11:41:32 +0300 |
commit | 9015ca359f271968edb16d19bad9fc340d8e3a3d (patch) | |
tree | 18a021dde0419880a033525f3bc1c1e4033a5e3f /doc/filters.texi | |
parent | e6547cce72789d6e650ae3017dcf6370e24f6314 (diff) |
lavfi/eq: rework expression evaluation
In particular, add support for t, pos, n, r parameters, and add an eval
mode option.
Also, partially reword option documentation.
With several major edit by Stefano Sabatini.
Signed-off-by: Stefano Sabatini <stefasab@gmail.com>
Diffstat (limited to 'doc/filters.texi')
-rw-r--r-- | doc/filters.texi | 70 |
1 files changed, 51 insertions, 19 deletions
diff --git a/doc/filters.texi b/doc/filters.texi index 3acd3e8c7f..0654531858 100644 --- a/doc/filters.texi +++ b/doc/filters.texi @@ -4366,40 +4366,72 @@ The filter accepts the following options: @table @option @item contrast -Set the contrast value. It accepts a float value in range @code{-2.0} to -@code{2.0}. The default value is @code{0.0}. +Set the contrast expression. The value must be a float value in range +@code{-2.0} to @code{2.0}. The default value is "0". @item brightness -Set the brightness value. It accepts a float value in range @code{-1.0} to -@code{1.0}. The default value is @code{0.0}. +Set the brightness expression. The value must be a float value in +range @code{-1.0} to @code{1.0}. The default value is "0". @item saturation -Set the saturation value. It accepts a float value in range @code{0.0} to -@code{3.0}. The default value is @code{1.0}. +Set the saturation expression. The value must be a float in +range @code{0.0} to @code{3.0}. The default value is "1". @item gamma -Set the gamma value. It accepts a float value in range @code{0.1} to @code{10.0}. -The default value is @code{1.0}. +Set the gamma expression. The value must be a float in range +@code{0.1} to @code{10.0}. The default value is "1". @item gamma_r -Set the gamma value for red. It accepts a float value in range -@code{0.1} to @code{10.0}. The default value is @code{1.0}. +Set the gamma expression for red. The value must be a float in +range @code{0.1} to @code{10.0}. The default value is "1". @item gamma_g -Set the gamma value for green. It accepts a float value in range -@code{0.1} to @code{10.0}. The default value is @code{1.0}. +Set the gamma expression for green. The value must be a float in range +@code{0.1} to @code{10.0}. The default value is "1". @item gamma_b -Set the gamma value for blue. It accepts a float value in range -@code{0.1} to @code{10.0}. The default value is @code{1.0}. +Set the gamma expression for blue. The value must be a float in range +@code{0.1} to @code{10.0}. The default value is "1". @item gamma_weight -Can be used to reduce the effect of a high gamma value on bright image areas, -e.g. keep them from getting overamplified and just plain white. It accepts a -float value in range @code{0.0} to @code{1.0}.A value of @code{0.0} turns the -gamma correction all the way down while @code{1.0} leaves it at its full strength. -Default is @code{1.0}. +Set the gamma weight expression. It can be used to reduce the effect +of a high gamma value on bright image areas, e.g. keep them from +getting overamplified and just plain white. The value must be a float +in range @code{0.0} to @code{1.0}. A value of @code{0.0} turns the +gamma correction all the way down while @code{1.0} leaves it at its +full strength. Default is "1". +@item eval +Set when the expressions for brightness, contrast, saturation and +gamma expressions are evaluated. + +It accepts the following values: +@table @samp +@item init +only evaluate expressions once during the filter initialization or +when a command is processed + +@item frame +evaluate expressions for each incoming frame +@end table + +Default value is @samp{init}. +@end table + +The expressions accept the following parameters: +@table @option +@item n +frame count of the input frame starting from 0 + +@item pos +byte position of the corresponding packet in the input file, NAN if +unspecified + +@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 @end table @subsection Commands |