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@@ -5276,6 +5276,69 @@ and also with custom gain:
 @end example
 @end itemize
 
+@section speechnorm
+Speech Normalizer.
+
+This filter expands or compresses each half-cycle of audio samples
+(local set of samples all above or all below zero and between two nearest zero crossings) depending
+on threshold value, so audio reaches target peak value under conditions controlled by below options.
+
+The filter accepts the following options:
+
+@table @option
+@item peak, p
+Set the expansion target peak value. This specifies the highest allowed absolute amplitude
+level for the normalized audio input. Default value is 0.95. Allowed range is from 0.0 to 1.0.
+
+@item expansion, e
+Set the maximum expansion factor. Allowed range is from 1.0 to 50.0. Default value is 2.0.
+This option controls maximum local half-cycle of samples expansion. The maximum expansion
+would be such that local peak value reaches target peak value but never to surpass it and that
+ratio between new and previous peak value does not surpass this option value.
+
+@item compression, c
+Set the maximum compression factor. Allowed range is from 1.0 to 50.0. Default value is 2.0.
+This option controls maximum local half-cycle of samples compression. This option is used
+only if @option{threshold} option is set to value greater than 0.0, then in such cases
+when local peak is lower or same as value set by @option{threshold} all samples belonging to
+that peak's half-cycle will be compressed by current compression factor.
+
+@item threshold, t
+Set the threshold value. Default value is 0.0. Allowed range is from 0.0 to 1.0.
+This option specifies which half-cycles of samples will be compressed and which will be expanded.
+Any half-cycle samples with their local peak value below or same as this option value will be
+compressed by current compression factor, otherwise, if greater than threshold value they will be
+expanded with expansion factor so that it could reach peak target value but never surpass it.
+
+@item raise, r
+Set the expansion raising amount per each half-cycle of samples. Default value is 0.001.
+Allowed range is from 0.0 to 1.0. This controls how fast expansion factor is raised per
+each new half-cycle until it reaches @option{expansion} value.
+Setting this options too high may lead to distortions.
+
+@item fall, f
+Set the compression raising amount per each half-cycle of samples. Default value is 0.001.
+Allowed range is from 0.0 to 1.0. This controls how fast compression factor is raised per
+each new half-cycle until it reaches @option{compression} value.
+
+@item channels, h
+Specify which channels to filter, by default all available channels are filtered.
+
+@item invert, i
+Enable inverted filtering, by default is disabled. This inverts interpretation of @option{threshold}
+option. When enabled any half-cycle of samples with their local peak value below or same as
+@option{threshold} option will be expanded otherwise it will be compressed.
+
+@item link, l
+Link channels when calculating gain applied to each filtered channel sample, by default is disabled.
+When disabled each filtered channel gain calculation is independent, otherwise when this option
+is enabled the minimum of all possible gains for each filtered channel is used.
+@end table
+
+@subsection Commands
+
+This filter supports the all above options as @ref{commands}.
+
 @section stereotools
 
 This filter has some handy utilities to manage stereo signals, for converting